Cisco Systems UBR900 User Manual

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Configuring the Cisco uBR900 Series

Cable Access Routers

This document addresses the following topics:

Feature Overview on page 1

Supported Platforms on page 32

Prerequisites on page 32

Supported MIBs and RFCs on page 33

Configuration Tasks on page 36

Configuration Examples on page 46

VoIP Bridging Configuration Using SGCP on page 52

Debug Commands on page 118

Glossary on page 135

Feature Overview

Cisco uBR900 series cable access routers are fully-functionalCisco IOS routers andstandards-basedbidirectional cable modems that give a residential or small office/home office (SOHO) subscriberhigh-speedInternet or Intranet access and packet telephone services via a sharedtwo-waycable system and IP backbone network. Cisco uBR900 series cable access routers are based on the currentData-Over-CableService Interface Specifications (DOCSIS) standards, and interoperate with any bidirectional,DOCSIS-qualifiedheadend cable modem termination system (CMTS).

Cisco uBR900 series routers connect computers, telephone equipment, and other customer premises devices at a subscriber site to the service provider’s Hybrid/Fiber Coax (HFC) and IP backbone network. Functioning as cable modems, the Cisco uBR900 series routers transport data and voice traffic on the same cable system that delivers broadcast TV signals.

Cisco uBR900 series cable access routers typically ship from the Cisco factory with a Cisco Internetwork Operating System (IOS) software image stored in nonvolatile memory (NVRAM). The standard Cisco IOS software image supports DOCSIS-compliantbridging operation for data as the default.

Based on the feature licenses purchased, other Cisco IOS images can be downloaded from Cisco Connection Online (CCO). Each Cisco uBR900 series router in your network can then be configured to support Voice over IP (VoIP) and/or other special operating modes based on your service offering and the practices in place for your network. A Cisco uBR900 series device can function as an advanced router, providing wide area network (WAN) data connectivity in a variety of configurations.

Configuring the Cisco uBR900 Series Cable Access Routers 1

Feature Overview

Cisco IOS Software Feature Sets

This section briefly describes the common feature sets supported by the Cisco uBR900 series cable access routers. Each feature set contains a number of features that provide a specific functionality such as Voice over IP (VoIP) or virtual private network (VPN) access.

The following feature set categories are currently available:

Data Operations

Data and Voice Operations

The data and voice feature sets add Voice over IP (VoIP) support to the same base features contained in the data only feature sets. Telephones that are connected to the uBR924 cable access router can make voice calls over the Internet using either the H.323 (Gateway/Gatekeeper) voice control protocol or Simple Gateway Control Protocol (SGCP). (For more information on these protocols, refer to H.323 Protocol Stack andSGCP Protocol Stack in this document.)

Because voice calls are real-timetraffic, the Cisco uBR924 cable access router supports the DOCSIS Quality of Service (QoS) enhancements to give higher priority to IP packets containing voice traffic.

Note Voice features are available only on the Cisco uBR924 cable access router.

Note Feature sets and software images vary depending on the cable access router model you are using and the Cisco IOS software release that is running. For a list of the available software images for your application, and the specific features contained in each image, refer to the release notes for the Cisco uBR900 series cable access router and Cisco IOS software release you are using. This document describes the features available for the Cisco uBR904 and uBR924 cable access routers in Cisco IOS Release 12.0(7)T.

The following feature sets are available in data and voice versions as well as in data only versions:

Base IP Bridging – provides full DOCSIS1.0-compliantcable modem support for users who want a basichigh-speedconnection to the Internet.

Home Office (Easy IP) – provides ahigh-speedconnection to the Internet, along with server functions that simplify the administration of IP addresses, so that the Cisco uBR900 series cable access router can connect a small number of computers to the Internet through the cable interface.

Small Office – provides a firewall feature set in addition to thehigh-speedInternet connection and server functions provided by the Home Office feature set. You can protect your office network from intrusion and interference while still havinghigh-speedaccess to the Internet.

Telecommuter – provides encryption and layer 2 tunneling support in addition to thehigh-speedInternet connection and server functions provided by the Home Office feature set. Businesses can establish securehigh-speedInternet connections between employees’ homes and the office local network.

These feature sets are described in the following sections.

2 Cisco IOS Release 12.0(7)T

Cisco IOS Software Feature Sets

Base IP Bridging

Base IP Bridging includes full and DOCSIS-compliantbridging andDOCSIS Baseline Privacy. The Base IP Bridging feature set allows the Cisco uBR900 series cable access router to function as a DOCSIS 1.0 cable modem and to interoperate with any DOCSIS1.0-qualifiedCMTS. It provides basichigh-speedInternet connectivity for users who want to connect only one computer to the cable network.

DOCSIS-compliantbridging (also referred to as“plug-and-play”bridging) is the default configuration for Cisco uBR900 series cable access routers. While inplug-and-playbridging mode, the router locates a downstream and upstream channel; finds ToD, TFTP, and DHCP servers; obtains an IP address; downloads a DOCSIS configuration file; and obtains DHCP parameters to work in bridging mode.

Note This feature set does not include Easy IP and Routing.

In DOCSIS-compliantbridging mode, the Cisco uBR900 series cable access router acts as a transparent bridge for the following device combinations:

3 CPE devices when using Cisco IOS Release 12.0(4) XI1 or higher

254 CPE devices when using Cisco IOS Release 12.0(5)T or higher images, or Cisco IOS Release 12.1.

Note The ability of the Cisco uBR900 series cable access router to grant access to CPE devices is controlled by the MAX CPE field in the DOCSIS configuration file. The MAX CPE field defaults to one CPE device unless otherwise set to a higher number.

Home Office (Easy IP)

The Home Office feature set provides high-speedInternet connectivity for customers who have a small home network (typically2-4computers). In addition to full DOCSIS 1.0 support and all of the functionality of theBase IP Bridging feature set, the Home Office feature set (also known as Easy IP) supports intelligent Dynamic Host Configuration Protocol (DHCP) server functions, including DHCP Relay Agent and DHCP Client functionality. It also supportsEasy IP (NAT/PAT).

This feature set allows the Cisco uBR900 series cable access router great flexibility in administering IP addresses for the PCs and other customer premises equipment it is connecting to the cable network. The DHCP functionality allows intelligent use of the IP addresses that allow customer premises computers and other equipment to connect to the Internet. The NAT/PAT functionality allows you to use private IP addresses on the local network, while still maintaining connectivity to the Internet.

Small Office

In addition to full DOCSIS 1.0 support and all of the functionality of the Easy IP feature set, the Small Office feature set supports the Cisco IOS firewall feature set which provides a wide range of security features for Cisco uBR900 series cable access routers. Using the firewall feature set, Cisco uBR900 series cable access routers act as buffers between the customer’s private enterprise network and the Internet and other connected public networks.

Configuring the Cisco uBR900 Series Cable Access Routers 3

Feature Overview

In firewall mode, the Cisco uBR900 series cable access router provides a high-speedInternet connection for an office’s local network while protecting the computers on the office network from common attacks such as denial of service attacks and destructive Java applets, as well asreal-timealerts of such attacks.

The Small Office feature set can be optionally extended with support for IPSec encryption to ensure that the traffic passed over the Internet cannot be intercepted. You can select either standard 56-bitIPSec Network Security encryption orhigh-security168-bitTriple Data Encryption Standard (DES) encryption.

Telecommuter

In addition to full DOCSIS 1.0 support and all of the functionality of the Easy IP feature set, the Telecommuter feature set supports IPSec encryption and the Layer 2 Tunneling Protocol (L2TP), which can establish secure high-speedInternet connections between employees’ homes and the office local network.

IPSec is an IP security feature that provides robust authentications and encryption of IP packets for the secure transmission of sensitive information over unprotected networks such as the Internet. You can select either standard 56-bitIPSec Network Security encryption orhigh-security168-bitTriple Data Encryption Standard (DES) encryption.

L2TP is an extension of the Point-to-PointProtocol (PPP) that allows computers on different physical networks to interoperate as if they were on the same local area network (LAN). These features are important components for Virtual Private Networks (VPNs).

Note The Telecommuter feature set does not require the firewall feature set because the individual telecommuter has a secure connection to the office network. The office network, however, should implement a firewall for its own connection to the Internet.

Data Operations

Figure 1 illustrates a typical broadband data cable system. Data transmitted to a Cisco uBR900 series cable access router from the service provider’s CMTS shares a 27 or 26 Mbps, 6 MHz data channel in the 88 to 860 MHz range. The Cisco uBR900 series cable access router shares an upstream data rate of up to 10 Mbps on a 200kHz-wideto 3.2MHz-widechannel in the 5 to 42 MHz range.

Note End-to-endthroughput varies based on the design and loading of network components, the mix of traffic, the processing speed and interface of the host server(s), the processing speed and local Ethernet performance of the subscriber’s computer, as well as other parameters. Since the network can be configured to support multiple levels of service to meet differing market price/performance requirements, the subscriber’s service level agreement also affects throughput. DOCSIS further contains some fundamental performance limitations because standards are designed to give a larger number of customers good performance, rather than permitting a few users to consume the entire capacity.

4 Cisco IOS Release 12.0(7)T

Data Operations

Figure 1 Typical Cisco Broadband Data Cable System

WAN

 

 

 

 

 

CMTS

 

Combiner

 

Tx

 

 

 

 

 

Switch/router

 

 

rack equipment

 

 

 

Rx

 

Fiber

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Servers

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Cisco uBR900 series cable access router

Internal backbone and

worldwide internet

HFC cable plant

Cable System Headend

Upstream and downstream data interfaces Operation support system interface Downstream RF interface

Upstream RF interface

18197

Residence or SOHO subscriber site: subscriber RF interface Ethernet interface

Operating Modes

The broadband data cable system uses multiple types of access control to ensure efficient use of bandwidth over a wide range of loading conditions. Advanced queuing techniques and service algorithms are used to define the acquisition and release of channels.

Cisco uBR900 series cable access routers support 64 or 256 Quadrature Amplitude Modulation (QAM) downstream, and Quadrature Phase Shift Keying (QPSK) or 16 QAM upstream transmission. This allows the CMTS system administrator to set the preferred modulation scheme based on the quality of the cable plant.

Note In noisy plant environments, 16 QAM upstream and 256 QAM downstream modulation may not be viable. Inhigh-qualityHFC networks capable of supporting 16 QAM formats in the upstream direction, Cisco recommends using QPSK forfixed-slotshort packets like maintenance or data requests, and 16 QAM for variable length data packets. This results in the most efficient use of the available upstream timeslots or minislots.

The system uses Transmission Control Protocol/Internet Protocol (TCP/IP) to transmit data. TCP/IP transmits data in segments encased in IP datagrams, along with checksums to detect data corruption and sequence numbers to ensure an ordered byte stream on the TCP connection between the Cisco cable access router and the CMTS.

Cisco cable access routers also support multicast services—datastreams sent to groups of subscribers. These applications utilize the User Datagram Protocol (UDP) instead of TCP. Since UDP does not mandate upstream acknowledgments, these applications can be very efficient in the network. Additionally, restricting upstream throughput will have no effect on downstream UDP streaming throughput.

Configuring the Cisco uBR900 Series Cable Access Routers 5

Feature Overview

Note Interactive games are the exception. Although low latency is required in gaming applications, high upstream data throughput is not demanded since the volume of data transmitted upstream is typically small.

Data Specifications

Table 1

Cisco uBR900 Series Cable Access Router Data Specifications

 

 

 

Description

Downstream Values

Upstream Values

 

 

 

Frequency Range

88 to 860 MHz

5 to 42 MHz

 

 

 

Modulation

64 QAM

QPSK

 

256 QAM

16 QAM

 

 

 

Data Rate

30 Mbps/64 QAM

QPSK—320Kbit/sec to 5 Mbit/sec

 

(27 Mbit/sec after FEC overhead)

 

 

42.8 Mbps/256 QAM

16 QAM—640Kbit/sec to 10 Mbit/sec

 

(36 Mbit/sec after FEC overhead)

 

 

 

 

Bandwidth

6 MHz

200K, 400K, 800K, 1.6M,

 

 

3.2 MHz

 

 

 

FEC

RS (122, 128) Trellis

Reed Solomon

 

 

 

One Channel

Receive level of digital signal

QPSK— +8 to +58 dBmV

 

-15to +15 dBmV

 

Note Most field measurements are of nearby

16 QAM— +8 to +55 dBmV

 

or adjacent analog signal which is normally

 

+6 to +10 dB (system specific) above the

 

digital signal level

 

Signal-to-NoiseRatio

64 QAM:

(SNR)

>23.5 dB @ BER<10^8

 

256 QAM*:

 

>30 dB @ BER <10^-8

 

(For input level between +15 and -8dBmV,

 

SNR must be greater than 30 dB. For input

 

level between -8and-15dBmV, SNR must be

 

greater than 33 dB.)

 

Note These performance numbers are in

 

laboratory-controlledconditions against

 

statistically pure noise sources (AWGN). Since

 

such conditions do not exist in practise, a 6 dB

 

or more SNR margin is required for reliable

 

operation. Check with your local system

 

guidelines.

QPSK:

>15 dB @ BER<10^-8

(QPSK will work at 98% successful ping rate for SNR>13 dB. A SNR of 15 dB will be needed to get almost optimal packets per minute transition.)

16 QAM:

>22 dB @ BER <10^-8

(For 16 QAM, a SNR>22 dB makes the grade for 98% ping efficiency. To get good packet rate, you need

SNR>25 dB)

Note These measurements were made for 0 and-10dBmV input to the CMTS, 1280 ksym/sec and 64 bytes packet size with a Cisco uBR904 cable access router andlaboratory-controlledconditions.

6 Cisco IOS Release 12.0(7)T

 

 

 

Data Operations

Table 1

Cisco uBR900 Series Cable Access Router Data Specifications (continued)

 

 

 

 

 

Description

Downstream Values

Upstream Values

 

 

 

 

 

Security

DES decryption: DOCSIS Baseline Privacy

DES encryption

(BPI), 40 bit-,56 bitand 168 bit DES encryption, as controlled by the headend and configuration files.

Note Cisco IOS images must contain encryption software at both the CMTS and the Cisco uBR900 series. Both routers must be enabled and properly configured to support encryption.

Service Assignments

Each Cisco uBR900 series cable access router on the network is configured to receive data on a particular downstream channel. A downstream channel contains upstream segment(s). Each upstream segment typically serves more than one fiber node.

Partitioning the upstream plant into smaller segments significantly reduces the number of potential ingress sources and failure points. The CMTS divides the cable plant into downstream channels and upstream segments or clusters of nodes.

Downstream and Upstream Data Transfer

When operating normally, the Cisco uBR900 series cable access router receives data addressed to it from the CMTS. The router reads the address in the header of the message, filters the message and forwards it to the appropriate device at the subscriber site.

Note Bandwidth at the subscriber site is shared by the active data users connected to the network segment.

For upstream data transfer, the Cisco cable access router uses a request/grant mechanism to obtain upstream bandwidth. The CMTS configures, via MAC messages, upstream parameters associated with transmissions from all Cisco cable access routers on the system. Service class registration is granted based on class assignment and load provisioning. Upstream channels are time slotted and divided into basic scheduling time units.

The CMTS informs the Cisco cable access router of minislot structures on the upstream channel. Some minislots are marked as contention-based—sharedby routers to make bandwidth (timeslot) requests with the CMTS. Others are grouped together into unicast grants for specific routers to send their data bursts. Yet others are grouped together into maintenance slots for “keep alive” messages from routers to the CMTS.

Bridging Applications

In bridging applications, the Cisco uBR900 series cable access router acts as a transparent bridge for up to 254 devices depending on the version of Cisco IOS software you are using. Older versions of software allow a maximum of 3 CPE devices to be bridged. The cable access router is connected to the Internet through the coaxial cable interface. All four 10BaseT Ethernet ports are treated as one Ethernet interface by the Cisco IOS software. The IP addresses for the CPE devices and the coaxial cable interface are typically in the same subnet, although this is not a requirement.

Configuring the Cisco uBR900 Series Cable Access Routers 7

Feature Overview

The Cisco uBR900 series complies with the DOCSIS standards for interoperable cable access routers; it supports full transparent bridging as well as DOCSIS-complianttransparent bridging.

Note If the attached CPE devices and the coaxial cable interface are in different IP subnets, the cable interface must have a secondary address.

Figure 2 Cisco uBR900 Series Cable Access Router in a Bridging Configuration

 

 

Ethernet

 

CATV

Ethernet

 

coaxial cable

Cisco uBR7200 series

Cisco uBR900 series

 

CMTS

 

cable access router

Ethernet

 

HFC network

 

 

 

 

 

Ethernet

PC

PC

PC

PC or hub

13305

DOCSIS-complianttransparent bridging is the factory default configuration of the Cisco uBR900 series cable access router. If your cable service provider is using a DHCP server, all you need to do is connect the cables and power on the cable access router; your service provider’s configuration program will automatically configure both the coaxial cable interface and the bridging functionality. You do not need to set up IP addresses for the attached PCs or enter any Command Line Interface (CLI) configuration commands. This type of operation is calledplug-and-playbridging.

In DOCSIS-compliantbridging mode, the cable access router is able to locate a downstream and upstream channel; find the TOD, TFTP, and DHCP server(s); obtain an IP address; download a DOCSIS configuration file; and obtain DHCP parameters to work in a bridging mode.

You can configure a customized bridging application on the Cisco uBR900 series using a downloadable configuration file or the CLI. See the sections “Configuring Bridging” on page 41 and“Customizing the Cable Access Router Interface” on page 44 for details.

Routing Applications

The Cisco uBR900 series cable access router can be configured to act as a router to preserve IP address space and limit broadcasts that can impact the performance of the network. A typical use would be if you are connecting the cable access router to an internal Ethernet hub that is connected to an existing PC network. The Cisco uBR900 series supports Routing Information Protocol Version 2 (RIP V2) for this application.

When configured in routing mode, the Cisco uBR900 series is automatically configured to use the headend’s IP address as its IP default gateway. This allows the cable access router to send packets not intended for the Ethernet interface to the headend when IP host-routingis configured.

RIP V2 routing is useful for small internetworks in that it enables optimization of Network Interface Center (NIC)-assignedIP addresses by definingvariable-lengthsubnet masks (VLSMs) for network addresses, and it allows classless interdomain routing (CIDR) addressing schema.

8 Cisco IOS Release 12.0(7)T

Data Operations

Figure 3 Cisco uBR900 Series Cable Access Router in a Routing Configuration with a Hub

CATV

 

 

 

coaxial cable

Cable

Ethernet

Ethernet

 

 

 

 

Modem

 

 

Cisco uBR7246

 

 

HUB

CMTS

 

 

 

 

 

HFC network

 

 

 

LAN

13306

Layer 2 Tunneling Protocol

Layer 2 Tunneling Protocol (L2TP) is an emerging Internet Engineering Task Force (IETF) standard that combines the best features of two existing tunneling protocols: Cisco’s Layer 2 Forwarding (L2F) and Microsoft’s Point-to-PointTunneling Protocol (PPTP). L2TP is an extension of thePoint-to-PointProtocol (PPP), which is an important component for Access Virtual Private Networks (VPNs).

Traditional dial-upnetworking services only supported registered IP addresses, which limited the types of applications that could be implemented over VPNs. L2TP supports multiple protocols and unregistered and privately administered IP addresses over the Internet. This allows the existing access infrastructure such as the Internet, modems, access servers, and ISDN terminal adapters (TAs) to be used.

L2TP can be initiated wherever PPTP or L2F is currently deployed, and can be operated as a client initiated tunnel such as PPTP, or a network access server (NAS) initiated tunnel such as L2F.

The current implementation of L2TP in Cisco IOS software is dependent on a PPP connection supported on one of the directly attached interfaces. A dial-upPPP connection is required in order to initiate an L2TP Tunnel connection. This is a requirement of the L2TP Access Concentrator (LAC). Currently the Cisco uBR900 series cable access router cannot function as the LAC; it can only function as the L2TP Network Server (LNS), which terminates a tunnel created elsewhere in the network.

Easy IP

Dynamic Host Configuration Protocol (DHCP) Server

Cisco uBR900 series cable access routers support Intelligent DHCP Relay and DHCP Client functionality. A DHCP Relay Agent is any host that forwards DHCP packets between clients and servers. A DHCP Relay Agent enables the client and server to reside on separate subnets. If the Cisco IOS DHCP server cannot satisfy a DHCP request from its own database, it can forward the DHCP request to one or more secondary DHCP servers defined by the network administrator using standard Cisco IOS IP helper-addressfunctionality.

Network Address Translation and Port Address Translation (NAT/PAT)

Network Address Translation (NAT) reduces the need for globally unique IP addresses. NAT allows an organization with addresses that are not globally unique to connect to the Internet by translating those addresses into globally routable address space.

Configuring the Cisco uBR900 Series Cable Access Routers 9

Feature Overview

Port Address Translation (PAT) is a similar mechanism that enables all internal hosts to share a single registered IP address (many-to-onetranslation). NAT/PAT:

Allows customers to maintain their own private networks while giving them full Internet access through the use of one or more global IP addresses

Allows several private IP addresses to use the same global IP address by using address overloading

Facilitates configuration and permits a large network of users to reach the network by using one Cisco uBR900 series cable access router and the same DOCSIS cable interface IP address

Eliminates the need to readdress all hosts with existing private network addresses (one-to-onetranslation) or by enabling all internal hosts to share a single registered IP address(many-to-onetranslation, also known as Port Address Translation [PAT])

Enables packets to be routed correctly to and from the outside world by using the Cisco uBR900 series cable access router

Allows personal computers on the Ethernet interface to have IP addresses to be mapped to the cable interface’s IP address

Routing protocols will run on the Ethernet interface instead of the cable interface, and all packets received are translated to the correct private network IP address and routed out the Ethernet interface. This eliminates the need to run RIP on the cable interface.

To implement NAT on the Cisco uBR900 series, the Ethernet interface is configured with an “inside” address and the cable interface is configured with an “outside” address. The Cisco uBR900 series also supports configuration of static connections, dynamic connections, and address pools.

Voice Over IP Operations

Note Voice features are available only on the Cisco uBR924 cable access router.

The Cisco uBR924 cable access router uses packets to transmit and receive digitized voice over an IP network. Voice signals are packetized and transported in compliance with H.323 or Simple Gateway Control Protocol (SGCP). H.323 is an International Telecommunications Union (ITU) standard that specifies call signaling and control protocols for a shared IP data network. SGCP is a Cisco/Bellcore-developed,out-of-bandsignaling protocol under review by the Internet Engineering Task Force (IETF).

Figure 4 illustrates a broadband cable system that supports VoIP transmission. Quality of Service (QoS) and prioritization schemes are used to enablereal-time(voice) andnon-real-timetraffic to coexist on the same channel. The CMTS routes IP telephony calls intermixed with other data traffic.

10 Cisco IOS Release 12.0(7)T

Voice Over IP Operations

Figure 4

Simplified VoIP Over Cable Network

 

Gateway/PSTN

 

Service

 

provider

 

backbone

CMTS rack

CMTS rack

equipment

equipment

Gatekeeper or

Policy

calling agents

server

HFC

HFC

cable plant

cable plant

Cisco uBR924

Cisco uBR924

 

Calling party

Called party

 

 

 

 

 

 

 

 

 

 

Residence or SOHO

Residence or SOHO

 

subscriber site 1

subscriber site 2

18194

Your company can then deploy IP telephony as a local-loopbypass service where voice packets are transferred from the CMTS to:

A telephony gatekeeper when using H.323; the Cisco uBR924 acts as an H.323 gateway.

A call agent when using SGCP.

The gatekeeper or call agents manage voice calls. The gateway interconnects the IP network to the public switched telephone network (PSTN).

Voice calls are digitized, encoded, compressed, and packetized in the originating gateway, then decompressed, decoded, and reassembled in the destination gateway. A server maintains subscriber profiles and policy information.

You can place and receive calls without using the local exchange carrier. Two simultaneous voice and fax calls are supported to and from each subscriber site. Multiple telephones and fax devices can be connected to each of the two VoIP telephone lines at a subscriber site, providing the 5 REN limit is adhered to for each telephone line.

Note the following requirements and characteristics of VoIP applications using the Cisco uBR924 cable access router:

The telephones at each subscriber site must support touch-tonedialing; rotary dialing is not supported.

Special telephone features such as call waiting, call forwarding, and conferencing are not supported.

A two-linetelephone can be connected to the V1+V2 port on the Cisco uBR924.

Fax devices—standardGroup III andcomputer-basedGroup III machines up to 14,400baud—aresupported in Cisco IOS images that support VoIP.

Configuring the Cisco uBR900 Series Cable Access Routers 11

Feature Overview

In general, fax/modem cards are not supported over VoIP links.

Contact your network management, provisioning, or operations team to determine what your network supports.

Voice Handling

The Cisco uBR924 cable access router supports the following compression and decompression algorithms (CODECs):

G.711 A Law 64000 bps

G.711 u Law 64000 bps

G.723.1 5300 bps

G.723.1 6300 bps

G.726 16000 bps

G.726 24000 bps

G.726 32000 bps

G.728 16000 bps

G.729 Annex-A8000 bps

G.729 8000 bps — Default CODEC for telephone calls

Caution Because voice transmission isdelay-sensitive,awell-engineerednetwork is critical.Fine-tuningyour network to adequately support VoIP typically involves a series of protocols and features geared to support Quality of Service (QoS).

To achieve acceptable voice quality and reduce network bandwidth usage, several voice processing techniques and services are employed, including echo cancellation, voice compression, Voice Activity Detection (VAD) or silence compression, and Dual Tone MultiFrequency (DTMF) tone detection and generation.

The Cisco uBR924 cable access router supports multiple QoS service IDs (SIDs), enabling multiple classes of service on the cable interface. This enables VoIP and data traffic to be treated separately, with all data assigned to a default class of service, while VoIP traffic is assigned to a different class of service. Thus, voice traffic from the Cisco uBR924’s telephone ports can take precedence over the data traffic coming from the Ethernet interfaces.

Note Separate class of service (CoS) streams are only available when the Cisco uBR924 is connected to a CMTS that supports multiple classes of service per router. In addition, the router’s configuration file must specify the use of multiple classes of service.

If the Cisco uBR924 interoperates with a DOCSIS 1.0 CMTS that does not support multiple CoS per router, voice traffic will be transmitted on a “best effort” basis along with data traffic. This may cause poorer voice quality and lower data throughput when calls are being made from the router’s telephone ports.

12 Cisco IOS Release 12.0(7)T

Voice Over IP Operations

The Cisco uBR924 cable access router supports the following service classes:

The first CoS in the router’s configuration file is configured as the “Tiered Best Effort Type Class” used by the router as the primary QoS for all regular data traffic. The class has no minimum upstream rate specified for the channel.

This service class results in the assignment of a primary SID for the router. In addition to being used as a data SID, the router uses this SID for all MAC message exchanges with the CMTS. Any SNMP management traffic from the network to the Cisco uBR924 will also use this SID.

While this class is strictly “best effort,” data traffic within this class can be prioritized into eight different priority levels. The CMTS system administrator, however, must define the supported upstream traffic priority levels and include the traffic priority fields in the configuration file downloaded to the Cisco uBR924.

When creating a configuration for the Cisco uBR924, the CMTS system administrator typically configures extra classes of service. These secondary classes of service are expected to be higher QoS classes and are used by higher priority traffic such as voice. These classes have a minimum upstream rate specified for the channel.

The multiple SID-per-routerfeature enables the Cisco uBR924 to use multiple SID queues for differentiated services. The Cisco uBR924 diverts voice call traffic to the higher QoS secondary SID, while forwarding “best effort” data from the Ethernet interface and MAC messages on the primary SID.

H.323 Protocol Stack

H.323 is an International Telecommunications Union (ITU) standard that specifies call signaling and control protocols for a shared IP data network. The Cisco uBR924 cable access router acts as an H.323 gateway. In architectures using the VoIP H.323 protocol stack, the session application manages two call legs for each call: (1) a telephony leg managed by the voice telephony service provider; (2) the VoIP leg managed by the cable system operator—theVoIP service provider. Use of the H.323 protocol typically requires a dial plan and mapper at the headend or other server location to map IP addresses to telephone numbers.

When both legs of the call have been set up, the session application creates a conference between them. The opposite leg’s transmit routine for voice packets is given to each provider. The CMTS router passes data to the gateway and gatekeeper. The H.323 stack provides signalling via H.225 and feature negotiation via H.245.

To make and receive H.323 calls, the Cisco uBR924 cable access router must know:

The IP address of the gateway for the destination dialed. You can configure these IP addresses statically using the voip dial peer group CLI commands, or you can obtain these addresses dynamically from the gatekeeper using Registration, Admission, and Status (RAS).

The telephone numbers of the attached devices. You can configure the telephone numbers attached to the Cisco uBR924 by configuring the IP addresses statically using the pots port CLI commands. When using Cisco Network Registrar (CNR) version 3.0 or higher with the relay.tcl and setrouter.tcl scripts, you can obtain these addresses dynamically from CNR. The telephone numbers of attached devices are then sent in DHCP response messages. When the Cisco uBR924 processes the DHCP response, it automatically creates thepots dial peer for each port, creates thevoip dial peer for the RAS target, and starts the H.323 RAS gateway support.

Configuring the Cisco uBR900 Series Cable Access Routers 13

Feature Overview

Note To support voice configurations involving Cisco gatekeeper products using RAS, the headend must have IP multicast enabled. The cable interface must be designated as the default for RAS to discover the gatekeeper. The gatekeeper then resolves all dialed destinations sent to the RAS protocol.

SGCP Protocol Stack

The Cisco uBR924 cable access router supports Simple Gateway Control Protocol (SGCP), an out-of-bandsignaling protocol that interacts with an external call agent (CA) to provide call setup and teardown for VoIP calls made through the Internet or a local intranet. Using the call control agent, SGCP communicates with the voice gateways, allowing you to create a distributed system that enhances performance, reliability, and scalability while still appearing as a single VoIP gateway to external clients. SGCP eliminates the need for a dial plan mapper and static configuration on the router to map IP addresses to telephone numbers because this function is provided by the external call agent.

In architectures using the SGCP protocol stack, the session application implements the gateway functionality defined to support both trunk and residential gateways. The Cisco uBR924 functions in this mode as a residential gateway with two endpoints.

SGCP can preserve Signaling System 7 (SS7) style call control information as well as additional network information such as routing information and authentication, authorization, and accounting (AAA) security information. SGCP allows voice calls to originate and terminate on the Internet, as well as allowing one end to terminate on the Internet and the other to terminate on a telephone or PBX on the PSTN.

Note The uBR924 cable access router supports both H.323 and SGCP call control, but only one method can be active at a time.

Voice Specifications

Table 2

Cisco uBR924 Cable Access Router Voice Specifications

 

 

 

Metric

 

Value

 

 

Loss (between DCS and BTI gateway)

Nominal: 4 dB ±.5 dB (off hook)

 

 

Nominal: 9 dB ±.5 dB (on hook)

 

 

Attenuation distortion:

Nominal:

DCS <> BTI (200Hz-3.5kHz)

+1 dB/-3dB

BTI<> DCS (304 Hz-3004Hz)

±0.5 dB

DCS ->BTI (204Hz-3004Hz)

±0.5 dB0

 

 

 

Idle channel noise

 

<= 18 dBmC (noise shall not exceed)

 

 

Signal to C-notchednoise

>= 35 dB

 

 

Inter-modulationdistortion:

 

R2

 

>= 52 dB

R3

 

>= 52 dB

 

 

Single frequency interference:

 

0 to 12 kHz

 

<= -28dBmO

0 to 4 kHz

 

<= -40dBmO

 

 

 

14 Cisco IOS Release 12.0(7)T

 

 

 

 

Voice Over IP Operations

 

Table 2

Cisco uBR924 Cable Access Router Voice Specifications (continued)

 

 

 

 

 

 

Metric

 

Value

 

 

 

 

 

 

Frequency shift (offset)

<= ±0.2 Hz (max)

 

 

 

 

<= ±0.1 Hz (99.5%)

 

 

 

 

 

Amplitude tracking (input Level, dBmO):

Max Dev.

Ave. Dev.

 

-37to 0(on-hook)

 

<= ±.5 dB

 

 

-37to +3 (off hook)

<= ±.5 dB

<= ± .25 dB

 

-50to-37(off-hook)

<= ±1.0dB

<= ±.5 dB

 

-55to-50(off-hook)

<= ± 3.0 dB

<= ±1.5 dB

 

 

 

 

 

 

Crosstalk

 

<= -65dBmO

 

 

 

 

 

 

 

Amplitude jitter

 

 

 

 

20-300Hz

 

<= 2.5% Peak

 

 

4-300Hz

 

<= 2.9% Peak

 

 

 

 

 

 

 

Phase jitter

 

<= 1.5 P-P

 

 

20 to 300 Hz

 

<= 1.8 P-P

 

 

4 to 300 Hz

 

 

 

 

 

 

 

 

 

 

 

Envelope delay distortion:

<= 350 usec

 

 

1704 Hz to 604 Hz

 

<= 195 usec

 

 

1704 Hz to 2804 Hz

<= 580 usec

 

 

1704 Hz to 204 Hz

 

<= 400 usec

 

 

1704 Hz to 3404 Hz

 

 

 

 

 

 

 

 

Hybrid balance:

 

 

 

 

Echo Return Loss (ERL)

> 26 dB (standard test line)

 

 

 

> 14 dB (station off hook)

 

SRL

 

> 21 dB (standard test line)

 

 

 

> 11 dB (station off hook)

 

 

 

 

 

 

Clipping:

 

 

 

 

Speech segments <5 ms

< 0.5%

 

 

Speech segments > 5ms

0.0%

 

 

 

 

 

 

 

Impulse noise:

 

 

 

 

(>= 6 dB below receive signal)

0 in 93% of all 15 min intervals

 

 

 

<= 1 count in all 30 min intervals

Phase hits (>= 10 deg)

0 in 99.75% of all 15 min intervals <= 1 count in all 30 min intervals

Gain hits (>= ± 3dB)

0 in 99.9% of all 15 min intervals <= 1 count in all 30 min intervals

Dropouts (>= 12)

0 in 99.9% of all 15 min intervals

 

<= 1 count in all 60 min intervals

 

 

Backup POTS Connection

The Cisco uBR924 cable access router provides an RJ-11port (Line) that connects to a standard analog telephone wall jack. In the event of a building power failure or a Cisco uBR924 power problem, the cutover port lets you dial out using the backup PSTN line. If the Cisco uBR924 loses power while VoIP calls are in progress, you can reestablish one of the twoconnections—dialingout over the PSTN.

Configuring the Cisco uBR900 Series Cable Access Routers 15

Feature Overview

Note The backup POTS connection enables only one of the VoIP ports on the Cisco uBR924 to function during a power outage. Calls in progress prior to the power outage will be disconnected. If power is reestablished while a cutover call is in progress, the connection will remain in place until the call is terminated. Once the cutover call is terminated, the router automatically reboots.

Security Features

Cisco uBR900 series cable access routers support the security features described in the paragraphs below.

DOCSIS Baseline Privacy

Support for DOCSIS Baseline Privacy in the Cisco uBR900 series is based on the DOCSIS Baseline Privacy Interface Specification (SP-BPI-I01-970922).It provides data privacy across the HFC network by encrypting traffic flows between the cable access router and the CMTS.

Baseline Privacy security services are defined as a set of extended services within the DOCSIS MAC sublayer. Two new MAC management message types, BPKM-REQandBPKM-RSP,are employed to support the Baseline Privacy Key Management (BPKM) protocol.

The BPKM protocol does not use authentication mechanisms such as passwords or digital signatures; it provides basic protection of service by ensuring that a cable modem, uniquely identified by its 48-bitIEEE MAC address, can only obtain keying material for services it is authorized to access. The Cisco uBR900 series cable access router is able to obtain two types of keys from the CMTS: the Traffic Exchange Key (TEK), which is used to encrypt and decrypt data packets, and the Key Exchange Key (KEK), which is used to decrypt the TEK.

IPSec Network Security

IPSec Network Security (IPSec) is an IP security feature that provides robust authentication and encryption of IP packets. IPSec is a framework of open standards developed by the Internet Engineering Task Force (IETF) providing security for transmission of sensitive information over unprotected networks such as the Internet. IPSec acts at the network layer (Layer 3), protecting and authenticating IP packets between participating IPSec devices (“peers”) such as the Cisco uBR900 series cable access router.

IPSec provides the following network security services:

Privacy—IPSeccan encrypt packets before transmitting them across a network.

Integrity—IPSecauthenticates packets at the destination peer to ensure that the data has not been altered during transmission.

Authentication—Peersauthenticate the source of allIPSec-protectedpackets.

Anti-replayprotection—Preventscapture and replay of packets; helps protect againstdenial-of-serviceattacks.

Triple Data Encryption Standard

The Data Encryption Standard (DES) is a standard cryptographic algorithm developed by the United States National Bureau of Standards. The Triple DES (3DES) Cisco IOS Software Release images increase the security from the standard 56-bitIPSec encryption to168-bitencryption, which is used for highly sensitive and confidential information such as financial transactions and medical records.

16 Cisco IOS Release 12.0(7)T

Security Features

Firewall

Cisco uBR900 series cable access routers act as buffers between any connected public and private networks. In firewall mode, Cisco cable access routers use access lists and other methods to ensure the security of the private network.

Cisco IOS firewall-specificsecurity features include:

Context-basedAccess Control (CBAC). This intelligently filters TCP and UDP packets based on theapplication-layerprotocol. Java applets can be blocked completely, or allowed only from known and trusted sources.

Detection and prevention of the most common denial of service (DoS) attacks such as ICMP and UDP echo packet flooding, SYN packet flooding, half-openor other unusual TCP connections, and deliberatemis-fragmentationof IP packets.

Support for a broad range of commonly used protocols, including H.323 and NetMeeting, FTP, HTTP, MS Netshow, RPC, SMTP, SQL*Net, and TFTP.

Authentication Proxy for authentication and authorization of web clients on a per-userbasis.

Dynamic Port Mapping. Maps the default port numbers for well-knownapplications to other port numbers. This can be done on ahost-by-hostbasis or for an entire subnet, providing a large degree of control over which users can access different applications.

Intrusion Detection System (IDS) that recognizes the signatures of 59 common attack profiles. When an intrusion is detected, IDS can either send an alarm to a syslog server or to a NetRanger Director, drop the packet, or reset the TCP connection.

User-configurableaudit rules.

Configurable real-timealerts and audit trail logs.

For additional information, see the description of the Cisco IOS Firewall Feature Set in the CiscoProduct Catalog, or refer to the sections on Traffic Filtering and Firewalls in theSecurity Configuration Guide andSecurity Command Reference available on Cisco Connection Online (CCO) and the DocumentationCD-ROM.

NetRanger Support—IOSIntrusion Detection

NetRanger is an Intrusion Detection System (IDS) composed of three parts:

A management console (director) that is used to view the alarms as well as to manage the sensors.

A sensor that monitors traffic. This traffic is matched against a list of known signatures to detect misuse of the network. This is usually in the form of scanning for vulnerabilities or for attacking systems. When a signature is matched, the sensor can track certain actions. In the case of the appliance sensor, it can reset (via TCP/rst) sessions, or enable “shuns” of further traffic. In the case of the IOS-IDS,it can drop traffic. In all cases, the sensor can send alarms to the director.

Communications through automated report generation of standardized and customizable reports and QoS/CoS monitoring capabilities.

Configuring the Cisco uBR900 Series Cable Access Routers 17

Feature Overview

Configuration Options

The Cisco uBR900 series cable access router typically ships from the factory ready to work in the Base IP Bridging (DOCSIS-compliantbridging)data-onlymode. The cable access router is configured automatically at startup by one or more configuration files generated by the cable service provider and downloaded to the router; no configuration or setup is required other than to connect the router to the cable system. The CMTS provides a path from the cable access router to the DHCP server for PC address assignment.

The PCs connected to the Cisco uBR900 series must be configured for Internet Protocol (IP). Using DHCP, the CMTS assigns an IP subnet address to the cable access router each time it connects to the network. The IP addresses of the cable access router and the individual PCs attached to it enable the CMTS to route data to and from the PCs.

Note When the Cisco uBR900 series cable access router is shipped from the factory, it is configured by default forDOCSIS-compliantbridging.

The configuration file or files downloaded to the Cisco uBR900 series by the CMTS at the headend are dependent on the services purchased by the individual cable service subscriber. The cable access router is provisioned in the following manner:

When the cable access router is first brought online, the CMTS downloads a binary file to the router that is in DOCSIS-specifiedformat. This file configures the router for the desired level of service and sets other parameters as needed.

If additional features are required beyond basic DOCSIS-compliantbridging, the DOCSIS configuration file can specify a Cisco IOS image that the CMTS should also download to the router. (To speed up the time required to bring the router online, the cable service provider can optionally preload the Cisco uBR900 series with the appropriate image at the warehouse.)

To customize the cable access router’s configuration further, the DOCSIS configuration file can also specify a Cisco IOS configuration file that the CMTS should download to the router. This second configuration file is an ASCII text file that contains the Cisco IOS commands needed to further configure the router as desired.

Note The CMTS typically downloads the DOCSIS configuration file, Cisco IOS image (if needed), and the Cisco IOS configuration file (if needed) only once when the router is initially brought online. However, a new configuration file or image can be downloaded whenever necessary, such as when the cable service provider offers new services or subscribers upgrade their services.

To ensure that you obtain the exact services that you have ordered, the Cisco uBR900 series arrives from the factory with a unique identifier (UID) that consists of a serial number and MAC address. These factory-assignedvalues are on a label at the bottom of the cable access router; for convenience, these values are also in a barcode label that can be easily scanned for entry into the service provider’s provisioning and billing system.

Using the MAC address of the cable access router as the key, the CMTS downloads the DOCSIS configuration file and Cisco IOS image that will provide the services that you have purchased. Service technicians at the headend typically create a number of standard configuration files to match the range of services offered by the provider; these configuration files can be created manually or with tools provided for this purpose by Cisco Systems.

18 Cisco IOS Release 12.0(7)T

Configuration Options

The following sections describe the initial power-onand provisioning sequences in more detail, as well as the requirements that must be met by both the cable access router and the CMTS before provisioning can be successful.

Initial Power-OnSequence

When connected and first powered on, the Cisco uBR900 series cable access router performs the following boot procedures:

Boots the Read Only Memory (ROM) from the ROMMON partition of its flash memory.

Performs a self-test,initializes processor hardware, and boots the main operating systemsoftware—theCisco IOS release image stored in NVRAM.

Next, the Cisco uBR900 series performs a series of DOCSIS-mandatedprocedures for automatic installation and configuration. These procedures are summarized inTable 3 and inFigure 5.

.

Table 3

Cable Access Router Initialization Sequences and Events

 

 

 

Sequence

Event

Description

 

 

 

1

Scan for a downstream channel and

The Cisco uBR900 series acquires a downstream channel by

 

establish synchronization with the

matching the clock sync signal that is regularly sent out by the

 

CMTS.

CMTS on the downstream channel. The cable access router

 

 

saves the last operational frequency in non-volatilememory

 

 

and tries to reacquire the saved downstream channel the next

 

 

time a request is made.

 

 

Note An ideal downstream signal is one that synchronizes

 

 

QAM symbol timing, FEC framing, MPEG packetization, and

 

 

recognizes downstream sync MAC layer messages.

 

 

 

2

Obtain upsteam channel parameters.

The cable access router waits for an upstream channel

 

 

descriptor (UCD) message from the CMTS and configures

 

 

itself for the upstream frequence specified in that message.

 

 

 

3

Start ranging for power adjustments.

The cable access router waits for the next upstream bandwidth

 

 

allocation map message (MAP) from the CMTS to find the

 

 

next shared request timeslot. The router then sends a ranging

 

 

request message on the next available shared request timeslot,

communicating its UID (its unique MAC address) using a temporary Service Identifier (SID) of 0 (zero) to indicate it has not yet been allocated an upstream channel.

In reply to the cable access router’s ranging request, the CMTS sends a ranging response containing a temporary SID to be used for the initial router configuration and bandwidth allocation. As needed, the router adjusts its transmit power levels using the power increment value given by the CMTS in its ranging response message.

Note At this point, the cable access router has established connectivity with the CMTS but is not yet online. The next steps allocate “permanent” upstream and downstream frequencies, as well as the configuration required for IP network connectivity.

Configuring the Cisco uBR900 Series Cable Access Routers 19

Feature Overview

Table 3

Cable Access Router Initialization Sequences and Events (continued)

 

 

 

Sequence

Event

Description

 

 

 

4

Establish IP connectivity.

After the next MAP message broadcast, the router uses a

 

 

shared require timeslot to invoke Dynamic Host Configuration

 

 

Protocol (DHCP) to establish IP connectivity with the TCP/IP

 

 

network at the headend.

 

 

The DHCP server sends a response containing the router’s IP

 

 

address as well as the IP addresses for the default gateway,

 

 

time of day (TOD) server, and Trivial File Transfer Protocol

 

 

(TFTP) server, and the DOCSIS configuration file to be

 

 

downloaded. Depending on the particular network

 

 

configuration, other information could be provided, such as

 

 

the IP addresses for a syslog server or security server.

 

 

Note The DHCP server is typically a dedicated server at the

 

 

headend, but it could also be a CMTS such as a Cisco uBR7200

 

 

series universal broadband router.

 

 

The router configures itself for the specified IP address and

 

 

gets the current date and time from the specified TOD server.

 

 

 

5

Establish the time of day.

The cable access router accesses the TOD server for the

 

 

current date and time, which is used to create time stamps for

 

 

logged events (such as those displayed in the MAC log file).

 

 

 

6

Establish security.

Full Security, a planned enhancement to Baseline Privacy, is

 

 

not fully defined nor currently supported by the DOCSIS

 

 

specification, and is therefore not supported by the

 

 

Cisco uBR900 series.

 

 

 

7

Transfer operational parameters.

Using TFTP, the router downloads the specified DOCSIS

 

 

configuration file and configures itself for the appropriate

 

 

parameters. The DOCSIS configuration file defines the

 

 

router’s operating mode such as the provisioned downstream

 

 

and upstream service assignments, including assigned

 

 

frequencies, data rates, modulation schemes, Class of Service

 

 

(CoS), type of services to support, and other parameters. Cisco

 

 

provides tools to help automate the creation of configuration

 

 

files.

 

 

Note The DOCSIS configuration file must be in the exact

 

 

format given by the DOCSIS specification. An incorrect

 

 

DOCSIS configuration file can cause the Cisco uBR900 series

 

 

to constantly cycle offline. Such errors include wrong

 

 

downstream frequency, wrong UCD, wrong downstream

 

 

Channel ID, invalid CoS, incorrect BPI privacy configurations

 

 

or shared secret strings.

 

 

The cable access router sends another registration request to

 

 

the CMTS containing the CoS parameters given in the

 

 

DOCSIS configuration file.

 

 

The CMTS verifies that the router is using the appropriate CoS

 

 

profile and converts the temporary SID into a data SID with a

 

 

service class index that points to the applicable CoS profile.

 

 

 

8

Perform registration.

The router completes its secondary ranging and is then online,

 

 

passing data between the HFC network and the PCs and other

 

 

CPE devices that are connected to the router.

 

 

 

20 Cisco IOS Release 12.0(7)T

 

 

 

Configuration Options

 

Table 3

Cable Access Router Initialization Sequences and Events (continued)

 

 

 

 

 

Sequence

Event

Description

 

 

 

 

9

Comply with baseline privacy.

If baseline privacy is configured and enabled on both the

 

 

 

router and CMTS, the router and CMTS negotiate the

 

 

 

appropriate encryption/decryption parameters and exchange

 

 

 

keys for privacy. After encryption is enabled, all information

 

 

 

sent within Ethernet packets is encrypted to prevent

 

 

 

interception or modification by an unauthorized party.

 

 

 

 

10

Enter the operational maintenance

As soon as the Cisco uBR900 series cable access router has

 

 

state.

successfully completed the above sequence, it enters

 

 

 

operational maintenance state.

 

 

 

 

At this point the router is online and operational in the basic DOCSIS bridging (“plug and play”) mode. If the DOCSIS configuration file specifies that the router must download a Cisco IOS image and a Cisco IOS configuration file, the router uses TFTP to download the image and configuration file into its local memory. It then installs the new IOS image and runs the configuration file.

Downloading a DOCSIS configuration file to a Cisco uBR900 series cable access router automatically:

ends all telnet sessions

disables the cable access router’s console port, preventing local access to the router’s CLI

performs a “write erase” on the cable access router’s local configuration parameters

Telnet access to the router from the headend is still allowed, but only if the Cisco IOS configuration file includes enable andline vty passwords; if the configuration file does not includeenable andline vty commands to specify these passwords, Telnet access and console access are both disabled.

Configuring the Cisco uBR900 Series Cable Access Routers 21

Feature Overview

The sequence numbers shown in Table 3 are also shown inFigure 5 below. The Cisco uBR900 series cable access router will complete all the steps shown in the table and flowchart each time it needs to reregister with the CMTS.

Figure 5

Cable Modem Initialization Flowchart

Power

on

1

2

3

4

5

Scan for downstream channel

Downstream sync established

Obtain upstream parameters

Upstream parameter acquired

Start

Ranging

Ranging and auto adjust completed

Establish

IP connectivety

IP complete

Establish time of day

Time of day established

Establish

security 6

Security established

Transfer operational 7 parameters

Transfer complete

Register with

the Cisco 8 uBR7246

Registration

complete

Baseline

privacy 9 initialization

Baseline privacy initialized

Operational 10

12960

22 Cisco IOS Release 12.0(7)T

wait_for_link_up_state.
maintenance_state

Basic Troubleshooting

Figure 6 illustrates the traffic flow during the initialization process.

Figure 6 Cisco uBR900 Series Cable Access Router Provisioning Overview

CMTS Interface

Cisco uBR900 series Cable Access Router

MAP Broadcast

Power on

 

Contains timesharing info

Establish synch and wait for UCD

Send UCD

 

 

 

Obtain upstream parameters

 

Use temporary SID

 

Extract slot info and upstream

 

channel to use

 

Start ranging

DHCP Response: Contains IP addresses

Default gateway, TOD server TFTP server address

TFTP boot config file name

ToD Response

Registration Response Contains Assigned SID

Cisco uBR900 series registered Fail if QoS not available

or authentication failed

Transmit ranging packet with SID

DHCP request/TFTP boot request Now in allocated slots

ToD Request

 

Registration Request

 

Send QoS Parameters

 

Now in allocated slots

 

Cisco uBR900 series online

18195

Note For more detail on the provisioning process, see the DOCSIS 1.0 Radio Frequency Interface (RFI) specification(SP-RFII01-990731or later revision).

After the Cisco uBR900 series cable access router goes online, it begins transferring data between the attached CPE devices and the network (internet, intranet, VoIP). The cable service provider typically uses DHCP to assign IP addresses to the CPE devices. The number of IP addresses each subscriber can obtain depends on the services purchased from the provider.

Basic Troubleshooting

A MAC-layercircular log file is stored inside the Cisco uBR900 series cable access router. This file contains a history of the log messages such as state event activities and timestamps. This is the most valuable information for troubleshooting the cable interface.

The MAC log file is displayed by entering the show controllers cable-modem 0 mac log command from privileged EXEC mode.

The most useful display fields in this output are the reported state changes. These fields are preceded by the message CMAC_LOG_STATE_CHANGE. These fields show how the Cisco uBR900 series progresses through the various processes involved in establishing communication and registration with the CMTS. The normal operational state is ; the normal state when the interface is shut down is

Note Because the MAC log file holds only a snapshot of 1023 entries at a time, you should try to display the file within 5 minutes after the reset or problem occurs.

Configuring the Cisco uBR900 Series Cable Access Routers 23

Feature Overview

The following is the normal progression of states as the Cisco uBR900 series registers with the CMTS:

wait_for_link_up_state ds_channel_scanning_state wait_ucd_state wait_map_state ranging_1_state ranging_2_state dhcp_state establish_tod_state security_association_state configuration_file_state registration_state establish_privacy_state maintenance_state

Following is an example of a MAC log file for a cable access router that has successfully registered with the headend CMTS. The output that is displayed is directly related to the messages that are exchanged between the Cisco uBR900 series and the CMTS.

uBR924# show controllerscable-modem0 mac log

 

 

508144.340

CMAC_LOG_DRIVER_INIT_IDB_RESET

0x08098FEA

508144.342

CMAC_LOG_LINK_DOWN

 

 

508144.344

CMAC_LOG_LINK_UP

 

 

508144.348

CMAC_LOG_STATE_CHANGE

ds_channel_scanning_state

508144.350

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

88/453000000/855000000/6000000

508144.354

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

89/93000000/105000000/6000000

508144.356

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

90/111250000/117250000/6000000

508144.360

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

91/231012500/327012500/6000000

508144.362

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

92/333015000/333015000/6000000

508144.366

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

93/339012500/399012500/6000000

508144.370

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

94/405000000/447000000/6000000

508144.372

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

95/123015000/129015000/6000000

508144.376

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

96/135012500/135012500/6000000

508144.380

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

97/141000000/171000000/6000000

508144.382

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

98/219000000/225000000/6000000

508144.386

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

99/177000000/213000000/6000000

508144.390

CMAC_LOG_WILL_SEARCH_SAVED_DS_FREQUENCY

699000000

508145.540

CMAC_LOG_UCD_MSG_RCVD

3

 

508146.120

CMAC_LOG_DS_64QAM_LOCK_ACQUIRED

699000000

508146.122

CMAC_LOG_DS_CHANNEL_SCAN_COMPLETED

 

 

508146.124

CMAC_LOG_STATE_CHANGE

wait_ucd_state

508147.554

CMAC_LOG_UCD_MSG_RCVD

3

 

508147.558

CMAC_LOG_UCD_NEW_US_FREQUENCY

20000000

508147.558

CMAC_LOG_SLOT_SIZE_CHANGED

8

 

508147.622

CMAC_LOG_FOUND_US_CHANNEL

1

 

508147.624

CMAC_LOG_STATE_CHANGE

wait_map_state

508148.058

CMAC_LOG_MAP_MSG_RCVD

 

 

508148.060

CMAC_LOG_INITIAL_RANGING_MINISLOTS

40

 

508148.062

CMAC_LOG_STATE_CHANGE

ranging_1_state

508148.064

CMAC_LOG_RANGING_OFFSET_SET_TO

9610

 

508148.066

CMAC_LOG_POWER_LEVEL_IS

28.0

dBmV (commanded)

508148.068

CMAC_LOG_STARTING_RANGING

 

 

508148.070

CMAC_LOG_RANGING_BACKOFF_SET

0

 

508148.072

CMAC_LOG_RNG_REQ_QUEUED

0

 

508148.562

CMAC_LOG_RNG_REQ_TRANSMITTED

 

 

508148.566

CMAC_LOG_RNG_RSP_MSG_RCVD

 

 

508148.568

CMAC_LOG_RNG_RSP_SID_ASSIGNED

2

 

508148.570

CMAC_LOG_ADJUST_RANGING_OFFSET

2408

 

508148.572

CMAC_LOG_RANGING_OFFSET_SET_TO

12018

 

508148.574

CMAC_LOG_ADJUST_TX_POWER

20

 

508148.576

CMAC_LOG_POWER_LEVEL_IS

33.0

dBmV (commanded)

508148.578

CMAC_LOG_STATE_CHANGE

ranging_2_state

24 Cisco IOS Release 12.0(7)T

Basic Troubleshooting

508148.580

CMAC_LOG_RNG_REQ_QUEUED

2

508155.820

CMAC_LOG_RNG_REQ_TRANSMITTED

 

508155.824

CMAC_LOG_RNG_RSP_MSG_RCVD

 

508155.826

CMAC_LOG_ADJUST_RANGING_OFFSET

-64

508155.826

CMAC_LOG_RANGING_OFFSET_SET_TO

11954

508155.828

CMAC_LOG_RANGING_CONTINUE

 

508165.892

CMAC_LOG_RNG_REQ_TRANSMITTED

 

508165.894

CMAC_LOG_RNG_RSP_MSG_RCVD

 

508165.896

CMAC_LOG_ADJUST_TX_POWER

-9

508165.898

CMAC_LOG_POWER_LEVEL_IS

31.0 dBmV (commanded)

508165.900

CMAC_LOG_RANGING_CONTINUE

 

508175.962

CMAC_LOG_RNG_REQ_TRANSMITTED

 

508175.964

CMAC_LOG_RNG_RSP_MSG_RCVD

 

508175.966

CMAC_LOG_RANGING_SUCCESS

 

508175.968

CMAC_LOG_STATE_CHANGE

dhcp_state

508176.982

CMAC_LOG_DHCP_ASSIGNED_IP_ADDRESS

188.188.1.62

508176.984

CMAC_LOG_DHCP_TFTP_SERVER_ADDRESS

4.0.0.1

508176.986

CMAC_LOG_DHCP_TOD_SERVER_ADDRESS

4.0.0.32

508176.988

CMAC_LOG_DHCP_SET_GATEWAY_ADDRESS

 

508176.988

CMAC_LOG_DHCP_TZ_OFFSET

360

508176.990

CMAC_LOG_DHCP_CONFIG_FILE_NAME

platinum.cm

508176.992

CMAC_LOG_DHCP_ERROR_ACQUIRING_SEC_SVR_ADDR

 

508176.996

CMAC_LOG_DHCP_COMPLETE

 

508177.120

CMAC_LOG_STATE_CHANGE

establish_tod_state

508177.126

CMAC_LOG_TOD_REQUEST_SENT

 

508177.154

CMAC_LOG_TOD_REPLY_RECEIVED

3107617539

508177.158

CMAC_LOG_TOD_COMPLETE

 

508177.160

CMAC_LOG_STATE_CHANGE

security_association_state

508177.162

CMAC_LOG_SECURITY_BYPASSED

 

508177.164

CMAC_LOG_STATE_CHANGE

configuration_file_state

508177.166

CMAC_LOG_LOADING_CONFIG_FILE

platinum.cm

508178.280

CMAC_LOG_CONFIG_FILE_PROCESS_COMPLETE

 

508178.300

CMAC_LOG_STATE_CHANGE

registration_state

508178.302

CMAC_LOG_REG_REQ_MSG_QUEUED

 

508178.306

CMAC_LOG_REG_REQ_TRANSMITTED

 

508178.310

CMAC_LOG_REG_RSP_MSG_RCVD

 

508178.312

CMAC_LOG_COS_ASSIGNED_SID

5/19

508178.314

CMAC_LOG_COS_ASSIGNED_SID

6/20

508178.316

CMAC_LOG_COS_ASSIGNED_SID

7/21

508178.318

CMAC_LOG_RNG_REQ_QUEUED

19

508178.320

CMAC_LOG_REGISTRATION_OK

 

508178.322

CMAC_LOG_REG_RSP_ACK_MSG_QUEUED

0

508178.324

CMAC_LOG_STATE_CHANGE

establish_privacy_state

508178.326

CMAC_LOG_NO_PRIVACY

 

508178.328

CMAC_LOG_STATE_CHANGE

maintenance_state

You can display other aspects of the MAC layer by adding the following keywords to the show controllers cable-modem 0 mac command:

uBR924# show controllerscable-modem0 mac ?

errors

Mac Error

Log data

hardware

All

CM Mac Hardware registers

log

Mac

log data

resets

Resets of

the MAC

state

Current MAC state

For examples and descriptions of how to use these keywords, see the show controllers cable-modem mac command reference page.

The MAC log file gives a detailed history of initialization events that occur in the Cisco uBR900 series cable access router. All pertinent troubleshooting information is stored here.

Configuring the Cisco uBR900 Series Cable Access Routers 25

Feature Overview

In the following paragraphs, a sample log file is broken down into the chronological sequence of events listed below. Sample comments are also included in the log file.

Event 1—Wait for the Link to Come Up

Event 2—Scan for a Downstream Channel, then Synchronize

Event 3—Obtain Upstream Parameters

Event 4—Start Ranging for Power Adjustments

Event 5—Establish IP Connectivity

Event 6—Establish the Time of Day

Event 7—Establish Security

Event 8—Transfer Operational Parameters

Event 9—Perform Registration

Event 10—Comply with Baseline Privacy

Event 11—Enter the Maintenance State

Event 1—Waitfor the Link to Come Up

When the Cisco uBR900 series cable access router is powered on and begins initialization, the MAC layer first informs the cable access router drivers that it needs to reset. The LINK_DOWN andLINK_UP fields are similar to the shut and no shut conditions on a standard Cisco interface.

uBR924# show controllerscable-modem0 mac log

 

528302.040

CMAC_LOG_LINK_DOWN

 

528302.042

CMAC_LOG_RESET_FROM_DRIVER

 

528302.044

CMAC_LOG_STATE_CHANGE

wait_for_link_up_state

528302.046

CMAC_LOG_DRIVER_INIT_IDB_SHUTDOWN

0x08098D02

528302.048

CMAC_LOG_LINK_DOWN

 

528308.428

CMAC_LOG_DRIVER_INIT_IDB_RESET

0x08098E5E

528308.432

CMAC_LOG_LINK_DOWN

 

528308.434

CMAC_LOG_LINK_UP

 

Event 2Scanfor a Downstream Channel, then Synchronize

Different geographical regions and different cable plants use different RF frequency bands. A frequency band is a group of adjacent 6 MHz-widechannels. These bands are numbered from 88 to 99. Each band has starting and ending digital carrier frequencies and a 6 MHz step size. For example, a search of EIA channels95-97is specified using band 89. The starting frequency of band 89 is 93 MHz; the ending frequency is 105 MHz.

The Cisco uBR900 series’ default frequency bands correspond to the North American EIA CATV channel plan for 6 MHz channel slots between 90 and 858 MHz. For example, EIA channel 95 occupies the 90-96MHz slot. The digital carrier frequency is specified as the center frequency of the slot, which is 93 MHz. Channel 95 is usually specified using the analog video carrier frequency of 91.25 MHz, which lies 1.75 MHz below the center of the slot.

Some CATV systems use alternative frequency plans such as the IRC (Incrementally Related Carrier) plan and HRC (Harmonically Related Carrier) plan. Cisco uBR900 series cable access routers support both of these plans. Most of the IRC channel slots overlap the EIA plan.

The Cisco uBR900 series uses a built-indefault frequency scanning feature to find and lock onto a downstream channel. After the cable access router successfully finds a downstream frequency channel, it saves the channel to NVRAM. The router recalls this value the next time it needs to synchronize its frequency.

26 Cisco IOS Release 12.0(7)T

Basic Troubleshooting

The downstream frequency search table is arranged so that the first frequencies that are scanned are above 450 MHz. Because many CATV systems have been upgraded from 450 MHz to 750 MHz coaxial cable, digital channels have a high chance of being assigned in the new spectrum. The search table omits channels below 90 MHz and above 860 MHz since the DOCSIS specification does not mandate their coverage.

The CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND field tells you what frequencies the cable access router will scan. TheCMAC_LOG_WILL_SEARCH_SAVED_DS_FREQUENCY field tells you the frequency the router locked onto and saved to NVRAM for future recall. TheCMAC_LOG_DS_64QAM_LOCK_ACQUIRED field communicates the same information. TheCMAC_LOG_DS_CHANNEL_SCAN_COMPLETED field indicates that the scanning and synchronization was successful.

508144.348

CMAC_LOG_STATE_CHANGE

ds_channel_scanning_state

508144.350

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

88/453000000/855000000/6000000

508144.354

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

89/93000000/105000000/6000000

508144.356

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

90/111250000/117250000/6000000

508144.360

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

91/231012500/327012500/6000000

508144.362

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

92/333015000/333015000/6000000

508144.366

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

93/339012500/399012500/6000000

508144.370

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

94/405000000/447000000/6000000

508144.372

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

95/123015000/129015000/6000000

508144.376

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

96/135012500/135012500/6000000

508144.380

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

97/141000000/171000000/6000000

508144.382

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

98/219000000/225000000/6000000

508144.386

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

99/177000000/213000000/6000000

508144.390

CMAC_LOG_WILL_SEARCH_SAVED_DS_FREQUENCY

699000000

508145.540

CMAC_LOG_UCD_MSG_RCVD

3

508146.120

CMAC_LOG_DS_64QAM_LOCK_ACQUIRED

699000000

508146.122

CMAC_LOG_DS_CHANNEL_SCAN_COMPLETED

 

Event 3—ObtainUpstream Parameters

The Cisco uBR900 series waits for an upstream channel descriptor (UCD) message from the CMTS. The UCD provides transmission parameters for the upstream channel.

508146.124

CMAC_LOG_STATE_CHANGE

wait_ucd_state

508147.554

CMAC_LOG_UCD_MSG_RCVD

3

508147.558

CMAC_LOG_UCD_NEW_US_FREQUENCY

20000000

508147.558

CMAC_LOG_SLOT_SIZE_CHANGED

8

508147.622

CMAC_LOG_FOUND_US_CHANNEL

1

508147.624

CMAC_LOG_STATE_CHANGE

wait_map_state

508148.058

CMAC_LOG_MAP_MSG_RCVD

 

508148.060

CMAC_LOG_INITIAL_RANGING_MINISLOTS

40

Event 4—StartRanging for Power Adjustments

The ranging process adjusts the transmit power of the cable access router. Ranging is performed in two stages: ranging state 1 and ranging state 2.

The CMAC_LOG_POWER_LEVEL_IS field is the power level that the CMTS told the Cisco uBR900 series to adjust to. TheCMAC_LOG_RANGING_SUCCESS field indicates that the ranging adjustment was successful.

508148.062

CMAC_LOG_STATE_CHANGE

ranging_1_state

508148.064

CMAC_LOG_RANGING_OFFSET_SET_TO

9610

 

508148.066

CMAC_LOG_POWER_LEVEL_IS

28.0

dBmV (commanded)

508148.068

CMAC_LOG_STARTING_RANGING

 

 

508148.070

CMAC_LOG_RANGING_BACKOFF_SET

0

 

508148.072

CMAC_LOG_RNG_REQ_QUEUED

0

 

508148.562

CMAC_LOG_RNG_REQ_TRANSMITTED

 

 

508148.566

CMAC_LOG_RNG_RSP_MSG_RCVD

 

 

Configuring the Cisco uBR900 Series Cable Access Routers 27

CMAC_LOG_TOD_COMPLETE
CMAC_LOG_DHCP_COMPLETE

Feature Overview

508148.568

CMAC_LOG_RNG_RSP_SID_ASSIGNED

2

 

508148.570

CMAC_LOG_ADJUST_RANGING_OFFSET

2408

 

508148.572

CMAC_LOG_RANGING_OFFSET_SET_TO

12018

 

508148.574

CMAC_LOG_ADJUST_TX_POWER

20

 

508148.576

CMAC_LOG_POWER_LEVEL_IS

33.0

dBmV (commanded)

508148.578

CMAC_LOG_STATE_CHANGE

ranging_2_state

508148.580

CMAC_LOG_RNG_REQ_QUEUED

2

 

508155.820

CMAC_LOG_RNG_REQ_TRANSMITTED

 

 

508155.824

CMAC_LOG_RNG_RSP_MSG_RCVD

 

 

508155.826

CMAC_LOG_ADJUST_RANGING_OFFSET

-64

 

508155.826

CMAC_LOG_RANGING_OFFSET_SET_TO

11954

 

508155.828

CMAC_LOG_RANGING_CONTINUE

 

 

508165.892

CMAC_LOG_RNG_REQ_TRANSMITTED

 

 

508165.894

CMAC_LOG_RNG_RSP_MSG_RCVD

 

 

508165.896

CMAC_LOG_ADJUST_TX_POWER

-9

 

508165.898

CMAC_LOG_POWER_LEVEL_IS

31.0

dBmV (commanded)

508165.900

CMAC_LOG_RANGING_CONTINUE

 

 

508175.962

CMAC_LOG_RNG_REQ_TRANSMITTED

 

 

508175.964

CMAC_LOG_RNG_RSP_MSG_RCVD

 

 

508175.966

CMAC_LOG_RANGING_SUCCESS

 

 

Event 5—EstablishIP Connectivity

After ranging is complete, the cable interface on the cable access router is UP. Now the cable access router accesses a remote DHCP server to get an IP address. The DHCP server sends a response containing the router’s IP address plus the TFTP server’s address, the Time of Day (TOD) server’s address, and the name of a configuration file containing additional configuration parameters. The

field shows that the IP connectivity was successful.

508175.968

CMAC_LOG_STATE_CHANGE

dhcp_state

508176.982

CMAC_LOG_DHCP_ASSIGNED_IP_ADDRESS

188.188.1.62

508176.984

CMAC_LOG_DHCP_TFTP_SERVER_ADDRESS

4.0.0.1

508176.986

CMAC_LOG_DHCP_TOD_SERVER_ADDRESS

4.0.0.32

508176.988

CMAC_LOG_DHCP_SET_GATEWAY_ADDRESS

 

508176.988

CMAC_LOG_DHCP_TZ_OFFSET

360

508176.990

CMAC_LOG_DHCP_CONFIG_FILE_NAME

platinum.cm

508176.992

CMAC_LOG_DHCP_ERROR_ACQUIRING_SEC_SVR_ADDR

 

508176.996

CMAC_LOG_DHCP_COMPLETE

 

Event 6Establishthe Time of Day

The Cisco uBR900 series accesses the Time of Day server for the current date and time, which is used to create time stamps for logged events. The field indicates a successful time of day sequence.

508177.120

CMAC_LOG_STATE_CHANGE

establish_tod_state

508177.126

CMAC_LOG_TOD_REQUEST_SENT

 

508177.154

CMAC_LOG_TOD_REPLY_RECEIVED

3107617539

508177.158

CMAC_LOG_TOD_COMPLETE

 

Event 7EstablishSecurity

This event is currently bypassed by the Cisco uBR900 series because “full security” has not been fully defined by DOCSIS and is therefore not yet supported.

508177.160

CMAC_LOG_STATE_CHANGE

security_association_state

508177.162

CMAC_LOG_SECURITY_BYPASSED

 

28 Cisco IOS Release 12.0(7)T

Note “Full security” was a request made by cable service providers for a very strong authorization and authentication check by the CMTS. The Cisco uBR900 series supports DOCSIS baseline privacy (Event 10), which protects your data from being “sniffed” on the cable network.
Event 8Transfer Operational Parameters
After completing the DHCP and security operations, the Cisco uBR900 series downloads operational parameters by downloading a configuration file located on the TFTP server. The CMAC_LOG_DHCP_CONFIG_FILE_NAME field shows the filename containing the transmission parameters.

Basic Troubleshooting

508177.164

CMAC_LOG_STATE_CHANGE

configuration_file_state

508177.166

CMAC_LOG_LOADING_CONFIG_FILE

platinum.cm

508178.280

CMAC_LOG_CONFIG_FILE_PROCESS_COMPLETE

 

Event 9PerformRegistration

After the Cisco uBR900 series is initialized, authenticated, and configured, it requests to be registered with the headend CMTS. The CMAC_LOG_COS_ASSIGNED_SID field assigns a class of service (CoS) number and a service ID (SID). Multiple CoS entries in the configuration file imply that multiple SIDs are supported by the cable access router. If several cable access routers use the same configuration file, they will have the same CoS numbers but will be assigned different SIDs.

A successful registration is indicated by the CMAC_LOG_REGISTRATION_OK field.

508178.300

CMAC_LOG_STATE_CHANGE

registration_state

508178.302

CMAC_LOG_REG_REQ_MSG_QUEUED

 

508178.306

CMAC_LOG_REG_REQ_TRANSMITTED

 

508178.310

CMAC_LOG_REG_RSP_MSG_RCVD

 

508178.312

CMAC_LOG_COS_ASSIGNED_SID

5/19

508178.314

CMAC_LOG_COS_ASSIGNED_SID

6/20

508178.316

CMAC_LOG_COS_ASSIGNED_SID

7/21

508178.318

CMAC_LOG_RNG_REQ_QUEUED

19

508178.320

CMAC_LOG_REGISTRATION_OK

 

Event 10Complywith Baseline Privacy

During this event, keys for baseline privacy are exchanged between the Cisco uBR900 series and the headend CMTS. A link level encryption is performed so that your data cannot be “sniffed” by anyone else on the cable network.

Following is a trace showing baseline privacy enabled. The key management protocol is responsible for exchanging two types of keys: KEKs and TEKs. The KEK (key exchange key, also referred to as the authorization key) is used by the CMTS to encrypt the TEKs (traffic encryption keys) it sends to the Cisco uBR900 series. The TEKs are used to encrypt/decrypt the data. There is a TEK for each SID that is configured to use privacy.

Configuring the Cisco uBR900 Series Cable Access Routers 29

Benefits

851.088

CMAC_LOG_STATE_CHANGE

establish_privacy_state

851.094

CMAC_LOG_PRIVACY_FSM_STATE_CHANGE

machine: KEK, event/state:

EVENT_1_PROVISIONED/STATE_A_START, new state: STATE_B_AUTH_WAIT

851.102

CMAC_LOG_BPKM_REQ_TRANSMITTED

 

851.116

CMAC_LOG_BPKM_RSP_MSG_RCVD

 

851.120

CMAC_LOG_PRIVACY_FSM_STATE_CHANGE

machine: KEK, event/state:

EVENT_3_AUTH_REPLY/STATE_B_AUTH_WAIT, new state: STATE_C_AUTHORIZED

856.208

CMAC_LOG_PRIVACY_FSM_STATE_CHANGE

machine: TEK, event/state:

EVENT_2_AUTHORIZED/STATE_A_START, new state: STATE_B_OP_WAIT

856.220

CMAC_LOG_BPKM_REQ_TRANSMITTED

 

856.224

CMAC_LOG_BPKM_RSP_MSG_RCVD

 

856.230

CMAC_LOG_PRIVACY_FSM_STATE_CHANGE

machine: TEK, event/state:

EVENT_8_KEY_REPLY/STATE_B_OP_WAIT, new state: STATE_D_OPERATIONAL

856.326

CMAC_LOG_PRIVACY_INSTALLED_KEY_FOR_SID

2

856.330

CMAC_LOG_PRIVACY_ESTABLISHED

 

Note In order for baseline privacy to work, you must use a code image name on the Cisco uBR900 series that contains the charactersk1. In addition, baseline privacy must be supported on the headend CMTS, and it must be turned on in the configuration file that is downloaded to the cable access router.

Event 11Enterthe Maintenance State

As soon as the Cisco uBR900 series has successfully completed the above events, it enters the operational maintenance state and is authorized to forward traffic into the cable network.

508178.322 CMAC_LOG_STATE_CHANGE

maintenance_state

Benefits

The Cisco uBR900 series cable access router provides the following benefits for data-over-cableapplications:

Allows telecommuters and small office/home office customers to leverage the high-bandwidth,low-cost,IP-baseddata and voice services offered by cable service providers

Enables the cost-effectivedeployment of advanced routing capabilities to the small office or home office site

Prioritizes voice traffic ahead of data traffic, ensuring quality of service (QoS) over a shared cable infrastructure

Leverages Cisco’s industry-standardrouting hardware and Cisco IOS software to deliver advanced networking services and applications such as virtual private networks (VPNs), support formulti-protocolnetworks, firewall security, and the ability tocost-effectivelydeploy local area networks (LANs)

30 Cisco IOS Release 12.0(7)T

Restrictions

Restrictions

When using the Cisco uBR900 series cable access router, keep the following restrictions and limitations in mind:

The Cisco uBR900 series is able to implement multiples classes of service (CoS) on the cable interface; however, separate CoS streams are only available when the cable access router is connected to a headend that supports multiple CoS per cable access router. In addition, the configuration file downloaded to the cable access router must specify the use of multiple CoS.

If the Cisco uBR900 series is connected to a DOCSIS 1.0 headend that does not support multiple CoS per cable access router, voice and data will be mixed, and voice traffic will be transmitted on a best effort basis. This may cause poorer voice quality and lower data throughput when calls are being made from the cable access router’s telephone ports. Voice quality is also affected when transmitting or downloading large files, as well as by other significant network traffic.

Note The Cisco uBR900 series cable access router is typically configured by the headend CMTS. Most cable service providers do not permit local configuration by individual subscribers.

Caution Before attempting to reconfigure a Cisco uBR900 series cable access router at a subscriber site, contact your network administrator, provisioning manager, or billing system administrator to ensure remote configuration is allowed. If remote configuration is disabled, settings you make and save at the local site will not remain in effect after the cable access router is powered off and back on. Instead, settings will return to the previous configuration.

Related Features and Technologies

The Cisco uBR900 series cable access router is intended to be used in conjunction with a Cisco uBR7246 or a Cisco uBR7223 universal broadband router located at the cable service provider’s headend facility. Other compatible headend devices may also be used with the Cisco uBR900 series.

Related Documents

For related information on the Cisco uBR900 series cable access router, refer to the following documents:

Quick Start Guide - Cisco uBR924 Cable Access Router Subscriber Setup

Quick Start Guide - Cisco uBR924 Cable Access Router Installation and Startup

Cisco uBR924 Installation and Configuration Guide

Regulatory Compliance and Safety Information for the Cisco uBR924 Cable Access Router

Cisco uBR7200 Series Installation and Configuration Guide

Cisco uBR7200 Series Configuration Notes

Cisco Network Registrar for the uBR7200 Series

Regulatory Compliance and Safety Information for the Cisco uBR7200 Series Universal Broadband Router

Cisco uBR7246 Universal Broadband Router Features

Cisco uBR7246 Universal Broadband Router Feature Enhancements

Configuring the Cisco uBR900 Series Cable Access Routers 31

Supported Platforms

Supported Platforms

The Cisco uBR900 series cable access router is a standalone device; it works in conjunction with the Cisco uBR7246 and the Cisco uBR7223 universal broadband routers.

Prerequisites

In order to use the Cisco uBR900 series cable access router for data-over-cableorvoice-over-cable(VoIP) applications, the following tasks must be completed:

All required CMTS routing and network interface equipment must be installed, configured, and operational. This includes all headend routers, servers (DHCP, TFTP and TOD), network management systems, and/or other configuration or billing systems in use in your network.

Based on the quality and capacity of your cable plant, your system administrator or network planner must define your network’s IP address allocation plan; spectrum management plan outlining the recommended operating parameters to optimize performance; channel plan identifying the channels available to assign to specific Cisco uBR900 series cable access routers; and dial plan based on the supported VoIP protocol.

The CMTS system administrator or appropriate personnel must specify the policy parameters for the Cisco uBR900 series and all computers and other customer premises devices to be supported at subscriber sites. Refer to Cisco’s Network Registrar (CNR) product documentation.

The CMTS system administrator or appropriate personnel must define and push DHCP and Cisco uBR900 series configuration files to the appropriate servers such that each cable access router, when initialized, can transmit a DHCP request, receive its IP address, obtain its TFTP and TOD server addresses, and download its configuration file (and updated Cisco IOS image, if required).

Note The MAC address on the cable access router ensures that each router downloads only the file(s) intended for it.

The Cisco uBR900 series cable access router must be physically installed and cabled as follows:

To the headend via CATV coaxial cable. (High-quality,shielded RF coaxial cable with at least 80% braid is recommended.)

To at least one PC via the straight-throughyellow Ethernet cable supplied with the cable access router. Refer to the appropriate cable access router quick start guide for detailed information.

Note When the Cisco uBR900 series is connected to an Ethernet hub, a crossover cable must be used. Category 5 UTP (10BaseT Ethernet) cable withRJ-45connectors is recommended.

Note For subscriber sites that support multiple telephones or fax devices on a telephone line, all wiring associated with the telephone line extension must be in place. Inside wiring must be in compliance with the country of operation to prevent degradation of service.

32 Cisco IOS Release 12.0(7)T

Supported MIBs and RFCs

The CMTS system administrator must ensure appropriate databases are updated to activate and support the new subscriber account in the provisioning, billing and/or network management systems in place for your network once each cable access router is registered with the CMTS.

The PC(s) connected to the Cisco uBR900 series cable access router must be configured for IP.

Cisco IOS Release 11.3(4)NA or later must be running on the Cisco uBR900 series cable access router. When the cable access router is up and running, you can display the Cisco IOS release number by entering the show version command from user EXEC mode.

Note If the Cisco uBR7246 universal broadband router at the cable headend is using MC16 modem cards, Cisco IOS Release 11.3(7)NA or later must be running on the Cisco uBR900 series cable access router.

In order to use the Cisco uBR900 series cable access router for VoIP-over-cableapplications, the following additional conditions must be met:

In order to run VoIP Fax, the uBR900 series cable access router must be configured for voice and you must be using Cisco IOS Release 12.0(5)T or higher.

Supported MIBs and RFCs

The Cisco uBR900 series cable access router supports the following categories of MIBs:

SNMP standard MIBs—Theseare the MIBs required by any agent supporting SNMPv1 or SNMPv2 network management. Specific MIBs in this category include:

CISCO-PRODUCT-MIB

CISCO-CHASSIS-MIB

CISCO-SYSLOG-MIB

CISCO-FLASH-MIB

BRIDGE-MIB

IF-MIB

CiscoWorks/CiscoView

The Cisco Voice MIBs consist of the following components:

VOICE-IF-MIB

VOICE-DIAL-CONTROL-MIB

VOICE-ANALOG-MIB

DIAL-CONTROL-MIB

CISCO-DIAL-MIB

SGCP-MIB

Cisco’s platform and network-layerenterpriseMIBs—TheseMIBs are common across most of Cisco’s router platforms. If your network management applications are already configured to support other Cisco routers, such as the Cisco 2600 series or Cisco 7200 series, no further configuration is needed unless the version of Cisco IOS software being used has updated these MIBs.

Configuring the Cisco uBR900 Series Cable Access Routers 33

Supported MIBs and RFCs

Cable-specificMIBs—TheseMIBs provide information about the cable interface and related information on the Cisco uBR900 series cable access router. They include bothDOCSIS-requiredMIBs andCisco-specificenterprise MIBs. If your network management applications have not already been configured for the Cisco uBR900 series cable access router, these MIBs must be loaded.

Cable-SpecificMIBs

Table 4 shows thecable-specificMIBs that are supported on the Cisco uBR900 series cable access router. This table also provides a brief description of each MIB’s contents and the Cisco IOS software release in which the MIB was initiallyfunctional—earlierreleases might have had unsupported prototype versions of the MIB; later releases might have added new attributes and functionality. Because of interdependencies, the MIBs must be loaded in the order given in the table.

Note The names given inTable 4 are the filenames for the MIBs as they exist on Cisco’s FTP site (ftp://ftp.cisco.com/pub/mibs/ or http://www.cisco.com/public/mibs). Most MIBs are available in both SNMPv1 and SNMPv2 versions; the SNMPv1 versions haveV1SMI as part of their filenames.

Table 4

Supported MIBs for the Cisco uBR900 Series Cable Access Router

 

 

 

 

 

MIB Filename

 

Description

Release

 

 

 

 

SNMPv2-SMI.my

 

Specifies the Structure of Management Information (SMI) for SNMPv2, as

12.0(4)XI

SNMPv2-SMI-V1SMI.my

defined in RFC 1902.

 

 

 

 

 

 

 

SNMPv2-TC.my

 

Defines the textual conventions as specified in pages 4, 10-11of RFC 854.

12.0(4)XI

SNMPv2-TC-V1SMI.my

 

 

 

 

 

 

CISCO-SMI.my

 

Specifies the Structure of Management Information (SMI) for Cisco’s

12.0(4)XI

CISCO-SMI-V1SMI.my

enterprise MIBs.

 

 

 

 

 

 

 

CISCO-TC.my

 

Defines the textual conventions used in Cisco’s enterprise MIBs.

12.0(4)XI

CISCO-TC-V1SMI.my

 

 

 

 

 

 

IF-MIB.my

 

Describes generic objects for the Layer 3 network interface sublayers. This

12.0(4)XI

IF-MIB-V1SMI.my

MIB is an updated version of MIB-II’sif table, and incorporates the

 

extensions defined in RFC 1229.

 

 

 

 

 

 

 

CISCO-CABLE-SPECTRUM-MIB.my

Describes the spectrum management flap list attributes.

12.0(5)T1

CISCO-CABLE-SPECTRUM-MIB-V1SMI.my

 

 

 

 

 

DOCS-IF-MIB.my

Describes the DOCSIS-compliantRadio Frequency (RF) interfaces in cable

12.0(4)XI

DOCS-IF-MIB-V1SMI.my

modems and cable modem termination systems. (This MIB is being updated

 

on a release basis to add RFC2670 support as needed.)

 

 

 

 

 

 

 

DOCS-BPI-MIB.my

Describes the attributes for the DOCSIS-specifiedBaseline Privacy

12.0(5)T

 

 

Interface (BPI) on cable modems and the CMTS (available in an SNMPv2

 

 

 

version only).

 

 

 

 

CISCO-DOCS-EXT-MIB.my

Extends the DOCSIS standard RFI MIB (DOCS-IF-MIB)

partial support:

CISCO-DOCS-EXT-MIB-V1SMI.my

with Cisco-specificextensions, such as QoS attributes and connection status

12.0(4)XI

and other information regarding the cable modems and CPE devices

 

 

 

full support:

 

 

supported by the CMTS.

 

 

12.0(5)T1

 

 

 

 

 

 

CABLE-DEVICE-MIB.my

Contains generic cable-relatedobjects forDOCSIS-compliantcable

12.0(4)XI

CABLE-DEVICE-MIB-V1SMI.my

modems.

 

 

 

 

 

 

 

34 Cisco IOS Release 12.0(7)T

Supported MIBs and RFCs

Table 4

Supported MIBs for the Cisco uBR900 Series Cable Access Router (continued)

 

 

 

 

 

MIB Filename

 

Description

Release

 

 

 

CISCO-CABLE-MODEM-MIB.my

Contains the Cisco enterprise objects for DOCSIS-compliantcable modems

12.0(4)XI

 

 

(available in an SNMPv2 version only).

 

 

 

 

DOCS-CABLE-DEVICE-MIB

DOCSIS-specifiedMIB forDOCSIS-compliantcable modems (available in

12.0(4)XI

 

 

an SNMPv2 version only).

 

 

 

 

 

The Cisco uBR900 series cable access router also supports the following:

Radio Frequency Interface Specification—Developedby the Multimedia Cable Network System (MCNS) consortium. This is theradio-frequencyinterface specification forhigh-speeddata-over-cablesystems.

CiscoWorks—Networkmanagement program for planning, troubleshooting, and monitoring Cisco internetworks. CiscoWorks uses Simple Network Management Protocol (SNMP) to monitor all SNMP devices.

For more information about CiscoWorks on CCO, follow this path:

Products & Ordering: Cisco Products: Network Management: CiscoWorks

For more information about CiscoWorks on the Documentation CD-ROM,follow this path:

Cisco Product Documentation: Network Management: CiscoWorks

Radio Frequency Interface (RFI) MIB—Specificto DOCSIS cable implementations. The RIF MIB provides an interface that permits management of the Cisco uBR900 series cable access router over the cable or Ethernet interface. Using SNMP management applications, this MIB allows access to statistics such as MAC, driver configuration, and counters. The Cable Device MIB is very similar to the RFI MIB in that both allow access to statistics; they are different in that the Cable Device MIB reports statistics on the cable access router, while the RFI MIB reports statistics on the radio frequency transmissions over the cable television line.

Simple Gateway Control Protocol (SGCP) MIB—Supportsconfiguration, performance, and fault management of the SGCP interface. The SGCP MIB components are as follows:

xgcplnBadVersions—Numberof incoming messages delivered to the protocol entity and that are for an unsupported protocol version

xgcpRequestTimeOut—Timeoutvalue used for retransmitting an unacknowledged message

xgcpRequestRetries—Numberof retries for a request that exceeds timeout

xgcpAdminStatus—Desiredstate of the protocol entity

xgcpOperStatus—Currentoperational status of the protocol entity

xgcpUnRecognizedPackets—Numberof unrecognized packets since reset

xgcpMsgStatTable—Tablethat contains SGCP statistics information since reset

xgcpMsgStatEntry—Rowin the xgcpMsgStatTable that contains information about SGCP message statistics per IP address of the Media Gateway Controller (MGC)

xgcpIPAddress—IPaddress of the MGC

xgcpSuccessMessages—Numberof successful messages that communicate with the MGC on that IP address

xgcpFailMessages—Numberof failed messages that communicate with the MGC on that IP address

Configuring the Cisco uBR900 Series Cable Access Routers 35

Configuration Tasks

xgcpUpDownNotification—Notificationsent when the protocol status changes between up and down

For descriptions of supported MIBs and how to use MIBs, see Cisco’s MIB web site on CCO at http://www.cisco.com/public/sw-center/netmgmt/cmtk/mibs.shtml.

Configuration Tasks

The Cisco uBR900 series cable access router typically is configured automatically on power-upusing a configuration file generated by the cable service provider and delivered via the CMTS installed at the cable headend. All of the configuration tasks listed below are optional.

Configuring a Host Name and Password on page 37

Configuring Ethernet and Cable Access Router Interfaces on page 38

Configuring Routing on page 39

Configuring Bridging on page 41

Reestablishing DOCSIS-Compliant Bridging on page 43

Customizing the Cable Access Router Interface on page 44

Using Multiple PCs with the Cable Access Router on page 45

Caution Before attempting to reconfigure a Cisco uBR900 series cable access router at a subscriber site, contact your network administrator, provisioning manager, or billing system administrator to ensure remote configuration is allowed. If remote configuration is disabled, settings you make and save at the local site will not remain in effect after the cable access router is powered off and back on. Instead, settings will return to the previous configuration.

Note Console sessions and TTY sessions are supported by the cable access router.

36 Cisco IOS Release 12.0(7)T

Configuring a Host Name and Password

Configuring a Host Name and Password

One of the first configuration tasks you might want to perform is to configure a host name and set an encrypted password. Configuring a host name allows you to distinguish multiple Cisco uBR900 series cable access routers from each other. Setting an encrypted password allows you to prevent unauthorized configuration changes.

Note Passwords are case sensitive.

To configure a host name and an encrypted password for a Cisco uBR900 series cable access router, perform the following tasks, starting in global configuration mode:

Step

Command

Purpose

1

uBR924(config)# hostname cisco

Change the name of the uBR900 series to a meaningful

 

cisco(config)#

name. Substitute your host name for cisco.

 

 

 

2

cisco(config)# enable secret guessme

Enter an enable secret password. This password provides

 

 

access to enable (privileged EXEC) mode.

 

 

After configuring a password, when you enter enable at

 

 

the EXEC prompt, you must enter the enable secret

 

 

password to gain access to configuration mode. Substitute

 

 

your enable secret password for guessme.

 

 

 

3

cisco(config)# line console 0

Enter line configuration mode to configure the console

 

 

port.

cisco(config-line)#exec-timeout 0 0

cisco(config-line)#exit cisco(config)#

Prevent the EXEC facility from timing out if you do not type any information on the console screen for an extended period.

Exit back to global configuration mode.

Verifying the Host Name and Password

To verify that you configured the correct host name and password, enter the show running-config command from global configuration mode:

cisco(config)# showrunning-config

Using 1888 out of 126968 bytes

!

version XX.X

.

.

!

hostname cisco

!

enable secret 5 $1$60L4$X2JYOwoDc0.kqa1loO/w8/

Check the host name and encrypted password displayed near the top of the command output.

Configuring the Cisco uBR900 Series Cable Access Routers 37

Configuring Ethernet and Cable Access Router Interfaces

Exit global configuration mode and attempt to reenter it using the new enable password:

cisco# exit

cisco con0 is now available Press RETURN to get started. cisco> enable

Password: guessme cisco#

Configuration, Verification, and Troubleshooting Tips

If you are having trouble:

Make sure Caps Lock is off.

Make sure you entered the correct passwords. Passwords are case sensitive.

Configuring Ethernet and Cable Access Router Interfaces

To assign an IP address to the Ethernet or cable access router interface so that it can be recognized as a device on the Ethernet LAN, perform the following tasks, starting in global configuration mode:

Step

Command

Purpose

1

uBR924(config)# interface ethernet 0

Enter interface configuration mode for the Ethernet and/or

 

 

the cable access router interface.

 

or

 

 

uBR924(config)# interfacemodem-cable0

 

 

uBR924(config-if)#

 

 

 

 

2

uBR924(config-if)# ip address 172.16.1.1 255.255.255.0

Assign the appropriate IP address and subnet mask to the

 

 

interface.

 

 

 

3

uBR924(config-if)#Ctrl-Z

Return to privileged EXEC mode.

 

uBR924#

 

 

%SYS-5-CONFIG_I:Configured from console by console

This message is normal and does not indicate an error.

 

 

 

Verifying IP Address Configuration

To verify that you have assigned the correct IP address, enter the show arp command:

uBR924# show arp

 

 

 

 

Protocol

Address

Age (min)

Hardware Addr

Type

Interface

Internet

172.16.1.1

-

0009.0613.6030

ARPA

cable-modem0

Internet

4.0.0.28

-

00e0.1ed7.524d

ARPA

Ethernet0

Configuration, Verification, and Troubleshooting Tips

If you are having trouble:

Make sure you are using the correct IP address.

Make sure the cable interface is not shut down. Use the show running-config command to check the cable interface status.

38 Cisco IOS Release 12.0(7)T

Configuring Routing

Configuring Routing

DOCSIS-complianttransparent bridging is the factory default configuration of the Cisco uBR900 series cable access router. To change the configuration of your cable access router from bridging to routing using the CLI, perform the following tasks, starting in global configuration mode:

Step

Command

Purpose

1

uBR924(config)#interfacecable-modem0

Enter interface configuration mode for the cable access

 

 

router interface.

 

 

 

2

uBR924(config-if)#nocable-modemcompliant bridge

Turn off DOCSIS-compliantbridging.

 

uBR924(config-if)#no bridge-group 59

Remove the default bridge group assignment from the

 

 

cable interface.

 

uBR924(config-if)#end

Return to global configuration mode.

 

 

 

3

uBR924(config)#ip routing

Enable IP routing for the cable access router.

 

uBR924(config)#ip subnet-zero

Enable the use of subnet zero for interface addresses and

 

 

routing updates.

uBR924(config)#ip route <IP address of CMTS> <subnet mask of CMTS>

Create a static route to the CMTS to make sure that Time of Day (TOD) packets are properly routed out of the cable access router.

4

uBR924(config)#router rip

Enter router configuration mode and enable Routing

 

 

Information Protocol (RIP) on the cable access router.

 

 

 

5

uBR924(config-router)#network network-number

Specify the network connected to the cable access router

 

 

on which the RIP process will operate. If the cable access

 

 

router is attached to more than one network, enter each IP

 

 

address in a separate command.

 

 

 

6

uBR924(config-router)#end

Exit router configuration mode.

 

uBR924(config)#interfacecable-modem0

Return to interface configuration mode for the cable

 

 

access router interface.

 

 

 

7

uBR924(config-if)#ip rip receive v 2

Specify that only RIP Version 2 packets will be received

 

 

on the coaxial cable interface.

 

 

 

8

uBR924(config-if)#ip rip send v 2

Specify that only RIP Version 2 packets will be sent on

 

 

the coaxial cable interface.

 

 

 

9

uBR924(config-if)#end

Exit interface configuration mode for the cable access

 

uBR924(config)#interface ethernet0

router interface and enter interface configuration mode for

 

 

the Ethernet0 interface.

 

 

 

10

uBR924(config-if)#no bridge-group 59

Remove the default bridge group assignment from the

 

 

Ethernet0 interface.

 

 

 

11

uBR924(config-if)#ip rip receive v 2

Specify that only RIP Version 2 packets will be received

 

 

on this Ethernet interface.

 

 

 

12

uBR924(config-if)#ip rip send v 2

Specify that only RIP Version 2 packets will be sent on

 

 

this Ethernet interface.

 

 

 

13

uBR924(config-if)#Ctrl-z

Return to privileged EXEC mode.

 

uBR924#copyrunning-configstartup-config

Save the configuration to nonvolatile RAM so that it

 

Building configuration...

won’t be lost in the event of a reset, power cycle, or power

 

 

outage.

 

 

 

Configuring the Cisco uBR900 Series Cable Access Routers 39

Configuring Routing

Verifying Routing

To verify that bridging is not configured, routing is enabled, and that Routing Information Protocol is configured on the interfaces, enter the show startup-config command:

uBR924# showstartup-config

Building configuration...

Current configuration:

!

version 12.0 no service pad

no service password-encryptionserviceudp-small-serversservicetcp-small-servers

!

hostname uBR924

!

!

clock timezone - 4 ip subnet-zero

!

!

!

voice-port0

!

voice-port1

!

!

interface Ethernet0

ip address 10.1.0.33 255.255.0.0 no ip directed-broadcast

ip rip send version 2

ip rip receive version 2 no keepalive

!

interface cable-modem0

ip address 172.16.1.42 255.255.0.0 no ip directed-broadcast

ip rip send version 2

ip rip receive version 2 no keepalive

cable-modemdownstream saved channel 699000000 39 nocable-modemcompliant bridge

!

router rip network 4.0.0.0

network 172.16.0.0

!

ip classless

no ip http server

!

line con 0

transport input none line vty 0 4

!

end

40 Cisco IOS Release 12.0(7)T

Configuring Bridging

Configuring Bridging

The Cisco uBR900 series cable access router is configured for DOCSIS-complianttransparent bridging by default. If it becomes necessary toreconfigure the unit for bridging after it has been configured for routing, you can erase the routing configuration and return the unit to factory default configuration settings, or you can reconfigure the unit manually using the CLI. To return the cable access router to factory default settings, see the section“Reestablishing DOCSIS-Compliant Bridging” on page 43 for details. To reconfigure the cable access router manually, perform the following tasks, starting in global configuration mode:

Step

Command

Purpose

1

uBR924(config)#no service pad

Disable packet assembler/disassembler commands;

 

 

prevent the uBR900 series from accepting incoming or

 

 

outgoing Packet Assembler/Disassembler (PAD)

 

 

connections.

 

 

 

2

uBR924(config)#no servicepassword-encryption

Disable password encryption.

 

 

 

3

uBR924(config)#no ip routing

Disable IP routing on the uBR900 series.

 

 

 

4

uBR924(config)#interface Ethernet0

Enter interface configuration mode for the Ethernet0

 

 

interface.

 

 

 

5

uBR924(config-if)#no ip address

Disable the IP address on the Ethernet0 interface.

 

 

 

6

uBR924(config-if)#no ip route-cache

Disable high-speedswitching caches for IP routing.

 

 

 

7

uBR924(config-if)#bridge-group bridge-group

Assign the Ethernet0 interface to a bridge group. The

 

 

bridge group must be an integer between 1 and 63.

 

 

 

8

uBR924(config-if)#bridge-group bridge-group

Disable spanning tree on the Ethernet interface.

 

spanning-disabled

 

 

 

 

9

uBR924(config-if)#end

Exit interface configuration mode for the Ethernet0

 

uBR924(config)#interfacecable-modem0

interface and enter interface configuration mode for the

 

 

cable access router interface.

 

 

 

10

uBR924(config-if)#no ip address

Disable the IP address of the coaxial cable interface, if

 

 

one has been set. The uBR7246 cable router assigns an IP

 

 

address to the cable access router each time it connects to

 

 

the network.

 

 

 

11

uBR924(config-if)#no ip route-cache

Disable high-speedswitching caches for IP routing on the

 

 

cable interface.

 

 

 

12

uBR924(config-if)#no keepalive

Disable keepalives on the cable interface.

 

 

 

13

uBR924(config-if)#cable-modemcompliant bridge

Enable DOCSIS-compliantbridging.

 

 

 

14

uBR924(config-if)#bridge-group bridge-group

Assign the cable access router interface to a bridge group.

 

 

The bridge group must be an integer from 1 to 63. (The

 

 

default is 59.)

 

 

 

15

uBR924(config-if)#bridge-group bridge-group

Disable spanning tree on the cable interface.

 

spanning-disabled

 

 

 

 

16

uBR924(config-if)#end

Exit interface configuration mode.

 

uBR924(config)#ip classless

(Optional) At times, the uBR900 series might receive

 

 

packets destined for a subnet of a network that has no

 

 

network default route. This global configuration mode

 

 

command allows the Cisco IOS software to forward such

 

 

packets to the best network route possible.

 

 

 

17

uBR924(config)#line console 0

Enter line configuration mode to configure the console

 

 

port.

 

 

 

Configuring the Cisco uBR900 Series Cable Access Routers 41

Configuring Bridging

Step

Command

Purpose

18

uBR924(config-line)#line vty 0 4

Identify the last line in a contiguous group of virtual

 

 

terminals you want to configure.

 

 

 

19uBR924(config-line)#Ctrl-z

uBR924#copyrunning-configstartup-config

Building configuration...

Return to privileged EXEC mode.

Save the configuration to nonvolatile RAM so that it won’t be lost in the event of a reset, power cycle, or power outage.

When the cable interface comes up, the IP address and downstream channel are configured automatically.

Note To configure multiple PCs, repeat Steps 4 through 7 above for each additional PC. You can connect a maximum of three PCs to the Cisco uBR900 series cable access router in a bridging application.

Verifying Bridging

To verify that routing has been disabled on all interfaces and that bridging has been reenabled, enter the show startup-config command from privileged EXEC mode:

uBR924# showstartup-config

Building configuration...

Current configuration:

!

version 12.0 service config no service pad

service timestamps debug uptime service timestamps log uptime no service password-encryption

!

hostname uBR924

!

clock timezone - 4 ip subnet-zero

no ip routing

!

!

voice-port0

!

!

voice-port1

!

!

interface Ethernet0 no ip address

no ip directed-broadcastno iproute-cachebridge-group59

bridge-group59spanning-disabled

!

42 Cisco IOS Release 12.0(7)T

Reestablishing DOCSIS-CompliantBridging

interface cable-modem0no ip address

no ip directed-broadcastno iproute-cache

no keepalive

cable-modemdownstream saved channel 699000000 36bridge-group59

bridge-group59spanning-disabled

!

ip classless

!

line con 0 line vty 0 4

login

!

end

Reestablishing DOCSIS-CompliantBridging

To erase the current non-defaultcable access router configuration and return the unit to its factory defaultDOCSIS-compliantbridging configuration, perform the following task from privileged EXEC mode:

Step

Command

Purpose

1

uBR924#erase startup config

Erase the current configuration (assuming the current

 

 

running configuration has been saved to NVRAM).

 

 

 

After entering this command, perform a warm reset of the Cisco uBR900 series cable access router by pressing and holding down the Reset button for less than 10 seconds. For information on the location and operation of the Reset button, refer to the “Physical Description” section in the chapter “Installing the Cisco uBR924 Cable Access Router” in the Cisco uBR924 Cable Access Router Installation and Configuration Guide.

Verifying DOCSIS-CompliantBridging

To verify that the cable access router is configured for DOCSIS-compliantbridging, enter theshow startup-config command from privileged EXEC mode. The configuration should look like this:

uBR924# showstartup-config

Building configuration...

Current configuration:

!

version 12.0 service config no service pad

service timestamps debug uptime service timestamps log uptime no service password-encryption

!

hostname uBR924

!

clock timezone - 4 ip subnet-zero

no ip routing

!

!

!

Configuring the Cisco uBR900 Series Cable Access Routers 43

Customizing the Cable Access Router Interface

voice-port0

!

!

voice-port1

!

!

interface Ethernet0 no ip address

no ip directed-broadcastno iproute-cachebridge-group59

bridge-group59spanning-disabled

!

interface cable-modem0no ip address

no ip directed-broadcastno iproute-cache

no keepalive

cable-modemdownstream saved channel 699000000 36bridge-group59

bridge-group59spanning-disabled

!

ip classless

no ip http server

!

line con 0

transport input none line vty 0 4

login

!

end

Customizing the Cable Access Router Interface

Different geographical regions and different cable plants use different frequency bands. The Cisco uBR900 series cable access router uses a built-indefault frequency scanning feature to address this issue. After the cable access router finds a successful downstream frequency channel, it saves the channel and power setting to NVRAM. The cable access router recalls this value the next time it needs to synchronize its frequency or register with the cable service provider’s CMTS.

However, you can customize the cable access router’s interface configuration if you need to deviate from the default setting that ships with the unit. For example, you might need to specify a different compliant mode, modify the saved downstream channel setting and upstream power value, or enable a faster downstream search algorithm.

Note Most cable network scenarios will not require you to use these commands.

To customize the cable access router interface, perform the following tasks, starting in global configuration mode:

Step

Command

Purpose

1

uBR924(config)#interfacecable-modem0

Specify cable access router interface 0.

 

 

 

2

uBR924(config-if)#cable-modemcompliant bridge

Enable DOCSIS-compliantbridging.

 

 

 

44 Cisco IOS Release 12.0(7)T

 

 

Using Multiple PCs with the Cable Access Router

 

 

 

Step

Command

Purpose

 

 

 

3

uBR924(config-if)#cable-modemdownstream saved channel

Modify the saved downstream channel setting and

 

ds-frequencyus-power

upstream power value. If you do this, you must specify an

 

 

exact downstream frequency and a power value.1

4

uBR924(config-if)#cable-modemfast-search

Enable a faster downstream search algorithm.

 

 

 

1Use the no cable-modem downstream saved channel ds-frequency us-power command to remove a saved frequency and power setting from NVRAM.

Using Multiple PCs with the Cable Access Router

The MAX CPE parameter in the DOCSIS configuration file determines how many PCs or other CPE devices are supported by a particular cable access router. The default value for the MAX CPE parameter is 1, which means only one PC can be connected to the cable access router unless this value is changed.

The DOCSIS 1.0 specification states that a CMTS cannot age-outMAC addresses for CPE devices. Thus, if MAX CPE = 1, the first PC that is connected to a cable access router is normally the only one that the CMTS recognizes as valid. If you wish to replace an existing PC or change its network interface card (NIC) to one that has a different MAC address, the CMTS will refuse to let the PC come online because this would exceed the maximum number of CPE devices specified by the MAX CPE parameter.

If you wish to replace an existing PC or NIC, use one of the following workarounds:

Use the clear cable host mac address reset command on the Cisco uBR7200 series router to remove the PC’s MAC address from the router’s internal address tables. The PC’s MAC address will be rediscovered and associated with the correct cable access router during the next DHCP lease cycle.

Power off the cable access router for approximately one minute and then power it back on so that the PC’s MAC address will be rediscovered and associated with the cable access router during the normal provisioning process. The PC might also have to be rebooted.

Increase the value of the MAX CPE parameter in the cable access router’s DOCSIS configuration file so that it can accommodate the desired number of PCs. Reset the cable access router to force it to load the updated configuration file.

Configuring the Cisco uBR900 Series Cable Access Routers 45

Configuration Examples

Configuration Examples

This section provides the following configuration examples:

Basic Internet Access Bridging Configuration on page 46

Basic Internet Access Routing Configuration on page 47

Multicast-Enabled Routing Configuration on page 48

VoIP Bridging Configuration Using H.323v2 on page 49

VoIP Routing Configuration Using H.323v2 on page 50

NAT/PAT Configuration on page 51

VoIP Bridging Configuration Using SGCP on page 52

IPSec Configuration on page 53

L2TP Configuration on page 54

Basic Internet Access Bridging Configuration

The following Cisco uBR900 series cable access router configuration supports a typical residential Internet-access,data only subscriber:

Current configuration:

!

version 12.0 service config no service pad

service timestamps debug uptime service timestamps log uptime no service password-encryption

!

hostname uBR924

!

clock timezone - 4 ip subnet-zero

no ip routing

!

voice-port0

!

voice-port1

!

interface Ethernet0

ip address 172.16.1.40 255.255.0.0 no ip directed-broadcast

no ip route-cachebridge-group59

bridge-group59spanning-disabled

!

interface cable-modem0

ip address 172.16.1.40 255.255.0.0 no ip directed-broadcast

no ip route-cache

cable-modemdownstream saved channel 699000000 36bridge-group59

bridge-group59spanning-disabled

!

ip classless

no ip http server

!

46 Cisco IOS Release 12.0(7)T

Basic Internet Access Routing Configuration

line con 0

transport input none line vty 0 4

login

!

end

Basic Internet Access Routing Configuration

The Cisco uBR900 series cable access router can be configured to act as a router to preserve IP address space and limit broadcasts that can impact the performance of the network. A sample configuration file follows.

Note To configure the Cisco uBR900 series to act as a router, theno cable-modem compliant bridge command must be used. In addition, thebridge group 59 command must be removed from the Ethernet andcable-modeminterfaces.

Current configuration:

!

version 12.0 service config no service pad

service timestamps debug uptime service timestamps log uptime no service password-encryption

!

hostname uBR924

!

clock timezone - 4 ip subnet-zero

!

voice-port0

!

voice-port1

!

interface Ethernet0

ip address 10.1.0.33 255.255.0.0 no ip directed-broadcast

!

interface cable-modem0

ip address 172.16.1.42 255.255.0.0 no ip directed-broadcast

cable-modemdownstream saved channel 699000000 39 nocable-modemcompliant bridge

!

router rip network 4.0.0.0

network 172.16.0.0

!

ip classless

no ip http server

!

line con 0

transport input none line vty 0 4

!

end

Configuring the Cisco uBR900 Series Cable Access Routers 47

Configuration Examples

Multicast-EnabledRouting Configuration

The following configuration is for a Cisco uBR900 series that uses PIM sparse-densemode and belongs to a specific multicast group. Other multicast routing protocols such as PIMsparse-modeor PIMdense-modecan be used.

Current configuration:

!

! Last configuration change at 23:16:44 - Thu Mar 18 1999

!

version 12.0 service config no service pad

service timestamps debug uptime service timestamps log uptime no service password-encryption

!

hostname uBR924

!

clock timezone - 4 ip subnet-zero

!

ip multicast-routing

ip dvmrp route-limit20000

!

voice-port0

!

voice-port1

!

interface Ethernet0

ip address 24.1.0.1 255.255.0.0 no ip directed-broadcast

ip pim sparse-dense-modeno iproute-cache

no ip mroute-cache

!

interface cable-modem0

ip address 10.1.0.25 255.255.0.0 no ip directed-broadcast

ip pim sparse-dense-modeno iproute-cache

no ip mroute-cache

cable-modemdownstream saved channel 477000000 56 nocable-modemcompliant bridge

!

!

router rip version 2 network 24.0.0.0

network 10.0.0.0

!

!

ip classless

no ip http server

!

!

line con 0

transport input none line vty 0 4

!

end

48 Cisco IOS Release 12.0(7)T

VoIP Bridging Configuration Using H.323v2

VoIP Bridging Configuration Using H.323v2

In this example, the Cisco uBR900 series is configured for bridging, with an H.323v2 dial peer to another Cisco uBR900 series attached to the same downstream interface on the headend CMTS.

Current configuration:

!

!Last configuration change at 21:54:41 - Thu Apr 29 1999

!NVRAM config last updated at 21:56:20 - Thu Apr 29 1999

version 12.0 no service pad

service timestamps debug uptime service timestamps log uptime no service password-encryption

hostname 2007

clock timezone - 3 ip subnet-zero

no ip routing

voice-port0 input gain-3

voice-port1 input gain-3

dial-peervoice 1 potsdestination-pattern6501 port 0

dial-peervoice 2 potsdestination-pattern6502 port 1

dial-peervoice 62 voipdestination-pattern620. session target ipv4:10.1.71.62

interface Ethernet0

ip address 10.1.71.65 255.255.255.0 no ip directed-broadcast

no ip route-cachebridge-group59

bridge-group59spanning-disabled

interface cable-modem0

description DHCP Reserved Address 10.1.71.65 ip address 10.1.71.65 255.255.255.0

no ip directed-broadcastno iproute-cache

cable-modemdownstream saved channel 537000000 27bridge-group59

bridge-group59spanning-disabled

ip classless

no ip http server

line con 0 exec-timeout0 0 transport input none

line vty 0 4 login

end

Configuring the Cisco uBR900 Series Cable Access Routers 49

Configuration Examples

VoIP Routing Configuration Using H.323v2

In this example, the Cisco uBR900 series is configured for IP routing, with an H.323v2 dial peer to another Cisco uBR900 series attached to the same downstream interface on the headend CMTS.

Current configuration:

!

! No configuration change since last restart

!

version 12.0 no service pad

service timestamps debug uptime service timestamps log uptime no service password-encryption

!

hostname 2007

!

class-mapclass-defaultmatch any

!

clock timezone - 3 ip subnet-zero

!

voice-port0

!

voice-port1

!

dial-peervoice 1 potsdestination-pattern6101 port 0

!

dial-peervoice 2 potsdestination-pattern6102 port 1

!

dial-peervoice 101 voipdestination-pattern620* codec g711alaw

session target ipv4:10.1.71.62

!

interface Ethernet0

ip address 24.1.61.1 255.255.255.0 no ip directed-broadcast

no ip mroute-cache

!

interface cable-modem0

ip address 10.1.71.61 255.255.255.0 no ip directed-broadcast

no ip mroute-cache

cable-modemdownstream saved channel 537000000 27 nocable-modemcompliant bridge

!

router rip version 2 network 10.0.0.0 network 24.0.0.0

no auto-summary<<==== Not necessary

!

no ip classless

ip route 0.0.0.0 0.0.0.0 10.1.71.1 no ip http server

!

50 Cisco IOS Release 12.0(7)T

NAT/PAT Configuration

line con 0 exec-timeout0 0 transport input none

line vty 0 4 login

!

!

end

NAT/PAT Configuration

Current configuration:

!

! No configuration change since last restart

!

version 12.0 no service pad

service timestamps debug uptime service timestamps log uptime no service password-encryption

!

hostname uBR924

!

!

ip nat inside source list 1 interface cable-modem0overload clock timezone --4

!

!

interface Ethernet0

ip address 10.1.1.1 255.255.255.0 ip nat inside

!

interface cable-modem0

ip address 24.3.90.20 255.255.255.0 ip nat outside

no keepalive

cable-modemdownstream saved channel 627000000 54 nocable-modemcompliant bridge

!

ip default-gateway24.3.90.2 ip classless

ip route 0.0.0.0 0.0.0.0 24.3.90.2 access-list1 permit any

!

line con 0 line vty 0 4

login

!

end

Configuring the Cisco uBR900 Series Cable Access Routers 51

Configuration Examples

VoIP Bridging Configuration Using SGCP

In this example, Cisco uBR924 is configured to support VoIP in bridging mode using SGCP. Note the following in the sample configuration file:

SGCP is enabled.

The call agent IP address is specified.

The SGCP application is specified for each port.

To configure this application via DHCP, the following fields must also be set:

Host name

Domain name

Domain Name System (DNS) server

Merit dump file — S:0:<call agen FQDN>:S:1<call agent FQDN>

Current configuration:

!

! Last configuration change at 16:30:00 - Thu Dec 16 1999

!

version 12.1 no service pad

service timestamps debug uptime service timestamps log uptime no service password-encryption

!

hostname art1

!

clock timezone - 0 6 ip subnet-zero

no ip routing

ip domain-namecisco.com ipname-server4.0.0.32

!

sgcp

!

xgcp snmp sgcp

!

!

voice-port0

!

voice-port1

!

dial-peervoice 100 pots application SGCPAPP port 0

!

dial-peervoice 101 pots application SGCPAPP port 1

!

process-max-time200

!

interface Ethernet0

ip address 188.186.1.14 255.255.0.0 no ip directed-broadcast

no ip route-cacheno ipmroute-cachebridge-group59

bridge-group59spanning-disabled

52 Cisco IOS Release 12.0(7)T

IPSec Configuration

!

interface cable-modem0

ip address 188.186.1.14 255.255.0.0 no ip directed-broadcast

no ip route-cacheno ipmroute-cache

cable-modemdownstream saved channel 699000000 27bridge-group59

bridge-group59spanning-disabled

!

ip classless

no ip http server

!

!

line con 0

transport input none line vty 0 4

login

!

end

IPSec Configuration

Note Encryption/decryption is subject to export licensing controls. To support IPSec, the

Cisco uBR900 series must be configured in routing mode. the software images running at both the headend and the subscriber end must support the feature set.

Note Careful address assignment on user equipment and policy routing at the headend is required. The headend may or may not use tunnels to convey traffic back to the corporate gateway.

For detailed information on IP security, L2TP, and Firewall, refer to the Security Configuration

Guide.

Current configuration:

!

Last configuration change at 23:24:55 - Thu Dedc 16 1999

!

version 12.1 no service pad

service timestamps debug uptime service timestamps log uptime

!

hostname Router

!

clock timezone - 0 6 ip subnet-zero

no ip domain-lookup

!

crypto isakmp policy 1 hash md5

authentication pre-sharelifetime 5000

crypto isakmp key 1111 address 30.1.1.1 crypto isakmp identity hostname

!

Configuring the Cisco uBR900 Series Cable Access Routers 53

Configuration Examples

crypto ipsec transform-settest-transformah-md5-hmacesp-desesp-md5-hmac

!

crypto map test-ipseclocal-addresscable-modem0crypto maptest-ipsec10ipsec-isakmp

set peer 30.1.1.1

set transform-settest-transformmatch address 100

!

interface Ethernet0

ip address 24.1.0.1 255.255.0.0 no ip directed-broadcast

!

interface cable-modem0

ip address 10.1.0.25 255.255.0.0 no ip directed-broadcast

no keepalive

cable-modemdownstream saved channel 213000000 30 nocable-modemcompliant bridge

crypto map test-ipsecrouter rip

version 2 network 10.0.0.0 network 24.0.0.0

!

ip classless

no ip http server

!

access-list100 permit ip host 10.1.0.25 30.1.1.0 0.0.0.255

!

line con 0 exec-timeout0 0 transport input none

line vty 0 4 login

!

end

L2TP Configuration

Note Encryption/decryption is subject to export licensing controls. To support L2TP and Firewall, the Cisco uBR900 series must be configured in routing mode. Software images running at both the headend and the subscriber end must support the feature set.

Note Careful address assignment on user equipment and policy routing at the headend is required. The headend may or may not use tunnels to convey traffic back to the corporate gateway.

For detailed information on IP security, L2TP, and Firewall, refer to the Security Configuration Guide.

54 Cisco IOS Release 12.0(7)T

L2TP Configuration

Current configuration:

!

!Last configuration change at 20:24:59 - Thu Dec 23 1999

!NVRAM config last updated at 20:34:52 - Thu Dec 23 1999

version 12.1 no service pad

service timestamps debug uptime service timestamps log uptime

hostname Router

class-mapclass-defaultmatch any

clock timezone - 0 1 ip subnet-zero

ip tftp source-interfacecable-modem0no ipdomain-lookup

vpdn enable

vpdn-group1

accept dialin l2tp virtual-template1 remote L2TP_LAC no l2tp tunnel authentication

!

!

interface Ethernet0

ip address 80.1.1.1 255.255.255.0 no ip directed-broadcast

interface Virtual-Template1ip unnumbered Ethernet0

no ip directed-broadcast

peer default ip address pool dialup ppp authentication chap

!

interface cable-modem0ip address 255.255.0.0

no ip directed-broadcast

cable-modemdownstream saved channel 639000000 38 nocable-modemcompliant bridge

!

router rip version 2 network 10.0.0.0 network 24.0.0.0

!

ip local pool dialup 24.1.0.100 ip classless

no ip http server

!

line con 0

transport input none line vty 0 4

login

!

end

Configuring the Cisco uBR900 Series Cable Access Routers 55

Command Reference

Command Reference

This section describes the following cable-modeminterface commands for the Cisco uBR900 series cable access router for Cisco IOS Release 12.0(7)T:

cable-modem compliant bridge cable-modem downstream saved channel cable-modem fast-search

cable-modem upstream preamble qpsk cable-modem voip best-effort interface cable-modem

show bridge cable-modem show controllers cable-modem

show controllers cable-modem bpkm show controllers cable-modem des show controllers cable-modem filters

show controllers cable-modem lookup-table show controllers cable-modem mac

show controllers cable-modem phy show controllers cable-modem tuner show controllers cable-modem show interfaces cable-modem

All commands relating to VoIP applications are documented in the Cisco IOS Release 12.0 command references, or in Voice over IP for the Cisco AS5300, which can be accessed online or on the Documentation CDROM by going toNew Features in Cisco IOS Release 12.0(3)T.

All other commands used with this feature are documented in the Cisco IOS Release 12.0 command references.

In Cisco IOS Release 12.0(1)T or later, you can search and filter the output for show andmore commands. This functionality is useful when you need to sort through large amounts of output, or if you want to exclude output that you do not need to see.

To use this functionality, enter a show ormore command followed by the “pipe” character (|), one of the keywordsbegin,include, orexclude, and an expression that you want to search or filter on:

command | {begin | include | exclude} regular-expression

Following is an example of the show atm vc command in which you want the command output to begin with the first line where the expression “PeakRate” appears:

show atm vc | begin PeakRate

For more information on the search and filter functionality, refer to the Cisco IOS Release 12.0(1)T document, CLI String Search.

56 Cisco IOS Release 12.0(7)T

cable-modemcompliant bridge

cable-modemcompliant bridge

To enable DOCSIS-complianttransparent bridging for a cable access router interface at startup, use thecable-modem compliant command from interface configuration mode. Use theno form of this command to disableDOCSIS-compliantbridging for the interface.

cable-modemcompliant bridge

no cable-modemcompliant bridge

Syntax Description

This command has no arguments or keywords.

Defaults

Enabled

Command Modes

Interface configuration

Command History

Release

Modification

11.3 NA

This command was introduced.

 

 

Usage Guidelines

It is normally not necessary to enter this command in data-over-cablebridging applications becauseDOCSIS-compliantbridging is enabled by default. If you wish to do full transparent bridging rather thanDOCSIS-compliantbridging, use theno form of the command, then configure full transparent bridging using CLI commands. See the“Configuring Bridging” section on page 41 for instructions.

Examples

The following example shows how to enter the cable-modem compliant bridge command for a cable access router interface, starting from global configuration mode:

uBR924(config)# interfacecable-modem0

uBR924(config-if)# cable-modemcompliant bridge

uBR924(config-if)#

Configuring the Cisco uBR900 Series Cable Access Routers 57

cable-modemcompliant bridge

Related Commands

Command

Description

 

 

cable-modem downstream saved channel

Modifies the saved downstream channel setting and

 

upstream power value on the cable interface of a

 

Cisco uBR900 series.

 

 

cable-modem fast-search

Enables a faster downstream search algorithm on the cable

 

interface of a Cisco uBR900 series.

 

 

cable-modem upstream preamble qpsk

Enables the QPSK modulation scheme in the upstream

 

direction from the Cisco uBR900 series to the CMTS.

 

 

cable-modem voip best-effort

Allows voice traffic to be transmitted on the upstream via

 

best effort rather than by assigning it a higher priority class

 

of service.

 

 

58 Cisco IOS Release 12.0(7)T

cable-modemdownstream saved channel

cable-modemdownstream saved channel

To modify the saved downstream channel setting and upstream power value on a cable access router interface, enter the cable-modem downstream saved channel command from interface configuration mode. Use theno form of this command to remove the saved settings, which will be resaved at the next initialization cycle.

cable-modemdownstream saved channelds-frequency us-power

no cable-modemdownstream saved channelds-frequency us-power

Syntax Description

ds-frequency

Downstream channel frequency in Hz, which can be from 91000000 to 860000000.

us-power

Upstream power level in decibels per millivolt (dBmV), which can be from 8 to 61.

Defaults

Enabled

Command Modes

Interface configuration

Command History

Release

Modification

11.3 NA

This command was introduced.

 

 

Usage Guidelines

This command is auto-generatedby the operation of the cable MAC layer process. The DOCSIS RFI specification requires that cable modems remember the downstream frequency and upstream power of the last successfully ranged session. These parameters are called up as the first downstream frequency and upstream power to use the next time the cable modem is booted. This operation dramatically speeds up the channel search.

Use the nocable-modemdownstream saved channelds-frequency us-power command to remove the saved frequency and power setting from the running configuration, which will be resaved at the next initialization cycle.

Cisco recommends that this command NOT be used by end users of the Cisco uBR900 series cable access router.

Examples

The following example shows how to remove the downstream frequency of 91000000 Hz and the upstream power level of 33 dBmV from the running configuration of a cable-modeminterface, starting from global configuration mode.

uBR924(config)# interfacecable-modem0

uBR924(config-if)# nocable-modemdownstream saved channel 91000000 33

uBR924(config-if)#

Configuring the Cisco uBR900 Series Cable Access Routers 59

cable-modemdownstream saved channel

Related Commands

Command

Description

 

 

cable-modem compliant bridge

Enables DOCSIS-complianttransparent bridging on the

 

Cisco uBR900 series at startup.

 

 

cable-modem fast-search

Enables a faster downstream search algorithm on the cable

 

interface of a Cisco uBR900 series.

 

 

cable-modem upstream preamble qpsk

Enables the QPSK modulation scheme in the upstream

 

direction from the Cisco uBR900 series to the CMTS.

 

 

cable-modem voip best-effort

Allows voice traffic to be transmitted on the upstream via

 

best effort rather than by assigning it a higher priority class

 

of service.

 

 

60 Cisco IOS Release 12.0(7)T

cable-modemfast-search

cable-modemfast-search

To enable a faster downstream search algorithm on a cable access router interface, use the cable-modem fast-search command from interface configuration mode. Use theno form of this command to disable the downstreamfast-searchfeature.

cable-modemfast-search

no cable-modemfast-search

Syntax Description

There are no keywords or arguments for this command.

Defaults

Disabled

Command Modes

Interface configuration

Command History

Release

Modification

11.3 NA

This command was introduced.

 

 

Usage Guidelines

This feature speeds up the frequency search performed by the cable access router. Normally it takes the cable access router about 30 to 50 seconds to sample 30 to 50 frequencies. The cable-modem fast-search command can reduce this search time. However, there might be some cases where thisfast-searchalgorithm might not perform as well as the default algorithm. Trial and error is the only way to discover how well this feature works for your environment.

Examples

The following example shows how to enter the cable-modem fast-search command, starting from global configuration mode:

uBR924(config)# interfacecable-modem0

uBR924(config-if)# cable-modemfast-search

uBR924(config-if)#

Configuring the Cisco uBR900 Series Cable Access Routers 61

cable-modemfast-search

Related Commands

Command

Description

 

 

cable-modem compliant bridge

Enables DOCSIS-complianttransparent bridging on the

 

Cisco uBR900 series at startup.

 

 

cable-modem downstream saved channel

Modifies the saved downstream channel setting and

 

upstream power value on the cable interface of a

 

Cisco uBR900 series.

 

 

cable-modem upstream preamble qpsk

Enables the QPSK modulation scheme in the upstream

 

direction from the Cisco uBR900 series to the CMTS.

 

 

cable-modem voip best-effort

Allows voice traffic to be transmitted on the upstream via

 

best effort rather than by assigning it a higher priority class

 

of service.

 

 

62 Cisco IOS Release 12.0(7)T

cable-modemupstream preamble qpsk

cable-modemupstream preamble qpsk

To enable the QPSK modulation scheme in the upstream direction from the cable access router interface to the headend, enter the cable-modem upstream preamble qpsk command from interface configuration mode. Use theno form of this command to disable upstream modulation for the interface.

cable-modemupstream preamble qpsk

no cable-modemupstream preamble qpsk

Syntax Description

This command has no arguments or keywords.

Defaults

Enabled

Command Modes

Interface configuration

Command History

Release

Modification

11.3 NA

This command was introduced.

 

 

Usage Guidelines

Examples

The following example shows how to enter the cable-modem upstream preamble qpsk command for a cable access router interface, starting from global configuration mode:

uBR924(config)# interfacecable-modem0

uBR924(config-if)# cable-modemupstream preamble qpskuBR924(config-if)#

Configuring the Cisco uBR900 Series Cable Access Routers 63

cable-modemupstream preamble qpsk

Related Commands

Command

Description

 

 

cable-modem compliant bridge

Enables DOCSIS-complianttransparent bridging on the

 

Cisco uBR900 series at startup.

 

cable-modem downstream saved channel Modifies the saved downstream channel setting and

 

upstream power value on the cable interface of a

 

Cisco uBR900 series.

 

 

cable-modem fast-search

Enables a faster downstream search algorithm on the cable

 

interface of a Cisco uBR900 series.

 

 

cable-modem voip best-effort

Allows voice traffic to be transmitted on the upstream via

 

best effort rather than by assigning it a higher priority class

 

of service.

 

 

64 Cisco IOS Release 12.0(7)T

cable-modemvoipbest-effort

cable-modemvoipbest-effort

To allow voice calls to be sent upstream over the cable interface via best effort, use the cable-modem voip best-effort command from interface configuration mode. To disablebest-effortvoice calls, use theno form of this command.

cable-modemvoipbest-effort

no cable-modemvoipbest-effort

Syntax Description

This command has no arguments or keywords.

Defaults

Enabled

Command Modes

Interface configuration

Command History

Release

Modification

12.0(5)T

This command was introduced.

 

 

Usage Guidelines

This command allows you to configure the voice traffic on a Cisco uBR900 series to allow only calls having a high priority service identifier (SID) to be connected.

If the dynamic configuration of high priority queues for voice traffic fails, or if the far end cannot support the multiple SIDs and multiple classes of service required by high priority traffic, the flag set by this command will be checked. If enabled (the default setting), the call will be allowed to go through. If disabled, the call will fail.

Examples

The following example shows how to disable best-effortvoice calls on a Cisco uBR900 series cable interface, starting from global configuration mode:

uBR924(config)# interfacecable-modem0uBR924(config-if)# nocable-modemvoipbest-effortuBR924(config-if)#

Configuring the Cisco uBR900 Series Cable Access Routers 65

cable-modemvoipbest-effort

Related Commands

Command

Description

 

 

cable-modem compliant bridge

Enables DOCSIS-complianttransparent bridging on the

 

Cisco uBR900 series at startup.

 

 

cable-modem downstream saved channel

Modifies the saved downstream channel setting and

 

upstream power value on the cable interface of a

 

Cisco uBR900 series.

 

 

cable-modem fast-search

Enables a faster downstream search algorithm on the cable

 

interface of a Cisco uBR900 series.

 

 

cable-modem upstream preamble qpsk

Enables the QPSK modulation scheme in the upstream

 

direction from the Cisco uBR900 series to the CMTS.

 

 

66 Cisco IOS Release 12.0(7)T

interface cable-modem

interface cable-modem

To specify the cable interface on a Cisco uBR900 series cable access router, enter the interface cable-modem command from global configuration mode.

interface cable-modemnumber

Syntax Description

number

The interface number of the cable interface on the rear panel of the cable access

 

router.

Defaults

Disabled

Command Modes

Global configuration

Command History

Release

Modification

11.3 NA

This command was introduced.

 

 

Usage Guidelines

When this command is entered, the Cisco uBR900 series cable access router switches from global configuration mode to interface configuration mode.

Examples

The following example brings up cable access router interface 0 and displays the available cable-modeminterface configuration commands:

uBR924(config)# interfacecable-modem0uBR924(config-if)# cable-modem?

compliant

Enter compliant modes

for

interface

downstream

Downstream channel

characteristics

fast-search

Enable/disable the

DS

fast search

upstream

upstream channel characteristics

voip

Options for Voice over IP

traffic over the cable interface

uBR924(config-if)#

Configuring the Cisco uBR900 Series Cable Access Routers 67

interface cable-modem

Related Commands

Command

Description

 

 

cable-modem compliant bridge

Enables DOCSIS-complianttransparent bridging on the

 

Cisco uBR900 series at startup.

 

 

cable-modem downstream saved channel

Modifies the saved downstream channel setting and

 

upstream power value on the cable interface of a

 

Cisco uBR900 series.

 

 

cable-modem fast-search

Enables a faster downstream search algorithm on the cable

 

interface of a Cisco uBR900 series.

 

 

cable-modem upstream preamble qpsk

Enables the QPSK modulation scheme in the upstream

 

direction from the Cisco uBR900 series to the CMTS.

 

 

cable-modem voip best-effort

Allows voice traffic to be transmitted on the upstream via

 

best effort rather than by assigning it a higher priority class

 

of service.

 

 

68 Cisco IOS Release 12.0(7)T

show bridge cable-modem

show bridge cable-modem

To display bridging information for a Cisco uBR900 series cable access router, enter the show bridge cable-modem command from privileged EXEC mode.

show bridge cable-modemnumber

Syntax Description

number

The interface number of the cable interface on the rear panel of the Cisco uBR900

 

series.

Defaults

No default behavior or values.

Command Modes

Privileged EXEC

Command History

Release

Modification

11.3 NA

This command was introduced.

 

 

Examples

Following is a sample output for this command:

uBR924# show bridgecable-modem0

Total of 300 station blocks, 298 free

Codes: P - permanent, S - self

Bridge Group 59:

Table 5 describes the significant fields shown in the display.

Table 5

show bridge cable-modemField Descriptions

 

 

 

Field

 

Description

 

 

Total of 300 station blocks

Total number of forwarding database elements in the system. The memory to hold

 

 

bridge entries is allocated in blocks of memory sufficient to hold 300 individual

 

 

entries. When the number of free entries falls below 25, another block of memory

 

 

sufficient to hold another 300 entries is allocated. Thus, the total number of

 

 

forwarding elements in the system is expanded dynamically, as needed, limited by

 

 

the amount of free memory in the router.

 

 

 

Bridge Group

 

The number of the bridge group to which this interface is assigned.

 

 

 

Configuring the Cisco uBR900 Series Cable Access Routers 69

show bridge cable-modem

Related Commands

Command

Description

 

 

show controllers cable-modem

Displays the current DHCP settings on point-to-point

 

interfaces.

 

 

show interfaces cable-modem

Displays information about the cable interface on the

 

Cisco uBR900 series cable access router.

 

 

70 Cisco IOS Release 12.0(7)T

show controllers cable-modem

show controllers cable-modem

To display high-levelcontroller information about a Cisco uBR900 series cable access router, use theshow controllers cable-modem command in privileged EXEC mode.

show controllers cable-modemnumber

Syntax Description

number

Controller number inside the Cisco uBR900 series.

Defaults

No default behavior or values.

Command Modes

Privileged EXEC

Command History

Release

Modification

11.3 NA

This command was introduced.

 

 

Usage Guidelines

The show controllers cable-modem display begins with information from the first few registers of the Broadcom BCM3300 chip. Next is buffer information for the receive, receive MAC message, buffer descriptor, and packet descriptor rings. Then comes MIB statistics from the BCM3300 chip, DMA base registers to indicate where the rings start, global control and status information, and finally interrupts for the interrupt code.

When using this command, be sure to check the tx_count and the tx_head and tx_tail values for the buffer descriptor (TX BD) and packet descriptor (TX PD) rings. The tx_count should be greater than 0, and the tx_head and tx_tail values should not be equal. If these values do not change for a long period of time, it indicates there are packets stuck on the ring. This condition is often caused by the headend not giving grants.

Configuring the Cisco uBR900 Series Cable Access Routers 71

show controllers cable-modem

Examples

Following is sample output for the show controllers cable-modem 0 command:

uBR924#

show

controllers cable-modem0

BCM Cable interface 0:

BCM3300

unit

0, idb 0x200EB4, ds 0x82D4748, regaddr = 0x800000, reset_mask 0x80

station

address 0010.7b43.aa01 default station address 0010.7b43.aa01

PLD VERSION:

32

MAC State is

ranging_2_state, Prev States = 7

MAC mcfilter

01E02F00 data mcfilter 01000000

DS: BCM

3116

Receiver: Chip id = 2

US: BCM

3037

Transmitter: Chip id = 30B4

Tuner: status=0x00

Rx: tuner_freq 699000000, symbol_rate 5055849, local_freq 11520000 snr_estimate 33406, ber_estimate 0, lock_threshold 26000

QAM in lock, FEC in lock, qam_mode QAM_64

Tx: tx_freq 20000000, power_level 0x3E, symbol_rate 1280000

DHCP: TFTP server = 4.0.0.32, TOD server = 4.0.0.188

Security server = 0.0.0.0, Timezone Offest = 0.0.4.32

Config filename =

buffer size 1600

RX data PDU ring with 32 entries at 0x201D40 rx_head = 0x201D78 (7), rx_p = 0x831BE04 (7)

00 pak=0x8326318 buf=0x225626 status=0x80 pak_size=0

01 pak=0x83241A0 buf=0x21DE5A status=0x80 pak_size=0

02 pak=0x83239C0 buf=0x21C22A status=0x80 pak_size=0

03 pak=0x8328C70 buf=0x22EA22 status=0x80 pak_size=0

04 pak=0x8325F28 buf=0x22480E status=0x80 pak_size=0

05 pak=0x8327CB0 buf=0x22B1C2 status=0x80 pak_size=0

06 pak=0x8323BB8 buf=0x21C936 status=0x80 pak_size=0

RX MAC message ring with 8 entries at 0x201E80 rx_head_mac = 0x201E88 (1), rx_p_mac = 0x831BE80 (1)

00 pak=0x8326120 buf=0x224F1A status=0x80 pak_size=0

01 pak=0x8324590 buf=0x21EC72 status=0x80 pak_size=0

02 pak=0x8323FA8 buf=0x21D74E status=0x80 pak_size=0

03 pak=0x8326EE8 buf=0x22806E status=0x80 pak_size=0

04 pak=0x8328E68 buf=0x22F12E status=0x80 pak_size=0

05 pak=0x8327AB8 buf=0x22AAB6 status=0x80 pak_size=0

06 pak=0x8328880 buf=0x22DC0A status=0x80 pak_size=0

07 pak=0x8326CF0 buf=0x227962 status=0xA0 pak_size=0

TX BD ring with 8 entries at 0x201FB8, tx_count = 0 tx_head = 0x201FD8 (4), head_txp = 0x831BF20 (4) tx_tail = 0x201FD8 (4), tail_txp = 0x831BF20 (4)

00 pak=0x000000 buf=0x200000 status=0x00 pak_size=0

01 pak=0x000000 buf=0x200000 status=0x00 pak_size=0

02 pak=0x000000 buf=0x200000 status=0x00 pak_size=0

03 pak=0x000000 buf=0x200000 status=0x00 pak_size=0

04 pak=0x000000 buf=0x200000 status=0x00 pak_size=0

05 pak=0x000000 buf=0x200000 status=0x00 pak_size=0

06 pak=0x000000 buf=0x200000 status=0x00 pak_size=0

07 pak=0x000000 buf=0x200000 status=0x20 pak_size=0

TX PD ring with 8 entries at 0x202038, tx_count = 0 tx_head_pd = 0x202838 (4)

tx_tail_pd = 0x202838 (4)

00 status=0x00 bd_index=0x0000 len=0x0000 hdr_len=0x0000

72 Cisco IOS Release 12.0(7)T

show controllers cable-modem

ehdr: 01 06 02 74 34 11

01 status=0x00 bd_index=0x0001 len=0x0000 hdr_len=0x0000 ehdr: 01 06 02 74 34 11

02 status=0x00 bd_index=0x0002 len=0x0000 hdr_len=0x0000 ehdr: 01 06 02 74 34 11

03 status=0x00 bd_index=0x0003 len=0x0000 hdr_len=0x0000 ehdr: 01 06 02 74 34 11

04 status=0x00 bd_index=0x0004 len=0x0000 hdr_len=0x0000 ehdr: 01 06 02 74 34 11

05 status=0x00 bd_index=0x0005 len=0x0000 hdr_len=0x0000 ehdr: 01 06 02 74 34 11

06 status=0x00 bd_index=0x0006 len=0x0000 hdr_len=0x0000 ehdr: 01 06 02 74 34 11

07 status=0x20 bd_index=0x0007 len=0x0000 hdr_len=0x0000 ehdr: 01 06 02 74 34 11

MIB Statistics

DS fifo full = 0, Rerequests = 0

DS mac msg overruns = 0, DS data overruns = 0

Qualified maps = 348, Qualified syncs = 73

CRC fails = 0, HDR chk fails = 0

Data pdus = 0, Mac msgs = 423

Valid hdrs = 423

BCM3300 Registers: downstream dma:

ds_data_bd_base=0x001D40, ds_mac_bd_base=0x001E80 ds_data_dma_ctrl=0x98, ds_mac_dma_ctrl=0xD8 ds_dma_data_index=0x0007, ds_dma_msg_index=0x0000

upstream dma:

us_bd_base=0x001FB8, us_pd_base=0x002038 us_dma_ctrl=0x80, us_dma_tx_start=0x00

Global control and status: global_ctrl_status=0x00

interrupts:

irq_pend=0x0008, irq_mask=0x00F7

Table 6 briefly describes some of the fields shown in the display. For more information, see the Broadcom documentation for the BCM3300 chip.

Table 6

show controllers cable-modemField Descriptions

 

 

 

Field

 

Description

 

 

 

BCM3300 unit

 

The unit number of this BCM3300 chip.

 

 

 

idb

 

Interface description block number.

 

 

 

ds

 

Downstream channel.

 

 

 

regaddr

 

Indicates the start of the BCM3300 registers.

 

 

 

reset_mask

 

Indicates the bit to hit when resetting the chip.

 

 

 

station address

 

MAC address of this Cisco uBR900 series cable access router interface.

 

 

default station address

Default MAC address assigned by the factory for this Cisco uBR900 series cable access

 

 

router.

 

 

 

PLD VERSION

 

PLD version of the BCM3300 chip.

 

 

 

MAC state

 

Current MAC state of the Cisco uBR900 series.

 

 

 

Prev States

 

Number of states that have previously existed since initialization.

 

 

 

MAC mcfilter

 

MAC control filter for MAC messages.

 

 

 

Configuring the Cisco uBR900 Series Cable Access Routers 73

show controllers cable-modem

Table 6

show controllers cable-modemField Descriptions (continued)

 

 

 

Field

 

Description

 

 

 

data mcfilter

 

MAC control filter for data.

 

 

 

DS

 

Downstream Broadcom receiver chip number and ID.

 

 

 

US

 

Upstream Broadcom transmitter chip number and ID.

 

 

 

Tuner: status

 

Current status of the tuner.

 

 

 

Rx: tuner_freq

 

Downstream frequency (in Hz) that the Cisco uBR900 series searched for and found.

 

 

 

symbol_rate

 

Downstream frequency in symbols per second.

 

 

 

local_freq

 

Frequency on which the transmitter and the tuner communicate.

 

 

 

snr_estimate

 

Estimate of signal-to-noiseratio (SNR) in Db X 1000.

 

 

 

ber_estimate

 

Estimate of bit error rate (always 0).

 

 

lock_threshold

Minimum signal-to-noiseratio (SNR) that the Cisco uBR900 series will accept as a

 

 

valid lock.

 

 

 

qam_mode

 

The modulation scheme used in the downstream direction.

 

 

 

Tx: tx_freq

 

Upstream frequency sent to the Cisco uBR900 series by the CMTS in the UCD

 

 

message.

 

 

 

power_level

 

Transmit power level as set in the hardware, expressed as a hexadecimal value. The

 

 

units are unique to the hardware used. Use the show controllers cable-modem 0 mac

 

 

state command to see the power level in dBmV.

 

 

 

symbol_rate

 

Upstream frequency in symbols per second.

 

 

 

TFTP server

 

IP address of the TFTP server at the headend.

 

 

 

TOD server

 

IP address of the time-of-dayserver at the headend.

 

 

 

Security server

 

IP address of the security server at the headend.

 

 

 

Timezone Offset

 

Correction received from the DHCP server to synchronize the Cisco uBR900 series

 

 

time clock with the CMTS.

 

 

 

Config filename

 

Name of the file stored on the cable company’s TFTP server that contains operational

 

 

parameters for the Cisco uBR900 series.

 

 

 

buffer size

 

Size in bytes of the BCM3300 message buffers.

 

 

RX data PDU ring:

Indicates the memory location of the beginning of buffer information for the receive

 

 

data ring.

rx_head

 

Indicates current head buffer descriptor.

rx_p

 

Indicates current head packet descriptor.

 

 

RX MAC message ring:

Indicates the memory location of the beginning of buffer information for the receive

 

 

MAC message ring.

rx_head_mac

 

Indicates current head buffer descriptor.

rx_p_mac

 

Indicates current head packet descriptor.

 

 

 

TX BD ring:

 

Indicates the memory location of the beginning of buffer information for the transmit

 

 

buffer descriptor ring.

tx_count tx_head

head_txp tx_tail tail_txp

If tx_count is 0, or if tx_head and tx_tail are equal and there is no change for a period of time, it means there are packets stuck on the ring. This condition may be caused by the headend not giving grants.

The next packet descriptor to get used, along with its index.

The next packet descriptor to get sent, along with its index. When head_txp and tail_txp are the same, the transmit queue is empty.

74 Cisco IOS Release 12.0(7)T

 

 

 

show controllers cable-modem

 

Table 6

show controllers cable-modemField Descriptions (continued)

 

 

 

 

 

Field

 

Description

 

 

 

 

 

TX PD ring:

 

Indicates the memory location of the beginning of buffer information for the transmit

 

 

 

packet descriptor ring.

 

tx_head_pd

 

Indicates current head packet descriptor.

 

tx_tail_pd

 

Indicates current tail packet descriptor.

 

ehdr

 

Extended MCNS header.

 

 

 

 

 

MIB Statistics:

 

 

 

 

 

 

 

DS fifo full

 

Number of times the downstream input first-infirst-out(FIFO) buffer became full on

 

 

 

the Cisco uBR900 series.

 

 

 

 

 

rerequests

 

Number of times a bandwidth request generated by the Cisco uBR900 series was not

 

 

 

responded to by the CMTS.

 

 

 

 

DS mac msg overruns

Number of times the Cisco uBR900 series’ DMA controller had a downstream MAC

 

 

 

message and there were no free MAC message buffer descriptors to accept the message.

 

 

 

 

 

DS data overruns

 

Number of times the Cisco uBR900 series’ DMA controller had downstream data and

 

 

 

there were no free data PDU buffer descriptors to accept the data.

 

 

 

 

 

Qualified maps

 

Number of times a MAP message passed all filtering requirements and was received by

 

 

 

the Cisco uBR900 series.

 

 

 

 

 

Qualified syncs

 

Number of times a timestamp message was received by the Cisco uBR900 series.

 

 

 

 

 

CRC fails

 

Number of times a MAC message failed a cyclic redundancy (CRC) check.

 

 

 

 

 

HDR chk fails

 

Number of times a MAC header failed its 16-bitCRC check. The MAC header CRC is a

 

 

 

16-bitHeader Check Sequence (HCS) field that ensures the integrity of the MAC

 

 

 

header even in a collision environment.

 

 

 

 

 

Data pdus

 

Total number of data PDUs (protocol data units) of all types received by the

 

 

 

Cisco uBR900 series.

 

 

 

 

 

Mac msgs

 

Number of MAC messages received by the Cisco uBR900 series.

 

 

 

 

 

Valid hdrs

 

Number of valid headers received by the Cisco uBR900 series, including PDU headers,

 

 

 

MAC headers, and headers only.

 

 

 

 

Global control and status:

Used to reset the BCM3300 chip.

 

 

 

 

 

interrupts:

 

Hexadecimal values of the pending IRQ interrupt and IRQ mask.

 

 

 

 

Configuring the Cisco uBR900 Series Cable Access Routers 75

show controllers cable-modem

Related Commands

Command

Description

 

 

show controllers cable-modem bpkm

Displays information about the baseline privacy key

 

management exchange between the Cisco uBR900 series and

 

the CMTS.

 

 

show controllers cable-modem des

Displays information about the Data Encryption Standard

 

(DES) engine registers.

 

 

show controllers cable-modem filters

Displays the registers in the MAC hardware that are used for

 

filtering received frames.

 

 

show controllers cable-modem

Displays the mini-slotlookup table inside a Cisco uBR900

lookup-table

series.

 

 

show controllers cable-modem mac

Displays detailed MAC-layerinformation for a Cisco uBR900

 

series.

 

 

show controllers cable-modem phy

Displays the contents of the registers used in the downstream

 

physical hardware of the Cisco uBR900 sereis.

 

 

show controllers cable-modem tuner

Displays the settings for the upstream and downstream tuners

 

used by a Cisco uBR900 series.

 

 

76 Cisco IOS Release 12.0(7)T

show controllers cable-modembpkm

show controllers cable-modembpkm

To display information about the baseline privacy key management exchange between the Cisco uBR900 series cable access router and the headend CMTS, use the show controllers cable-modem bpkm command in privileged EXEC mode.

show controllers cable-modemnumber bpkm

Syntax Description

number

Controller number inside the Cisco uBR900 series cable access router.

Defaults

No default behavior or values.

Command Modes

Privileged EXEC

Command History

Release

Modification

11.3 NA

This command was introduced.

 

 

Usage Guidelines

Baseline privacy key management exchanges take place only when both the Cisco uBR900 series and the CMTS are running code images that support baseline privacy, and the privacy class of service is enabled via the configuration file that is downloaded to the cable access router. Baseline privacy code images for the Cisco uBR900 series contain k1 in the code image name.

Examples

The following output is displayed when the headend CMTS does not have baseline privacy enabled:

uBR924# show controllerscable-modem0 bpkm

CM Baseline Privacy

Key Management

 

configuration (in

seconds):

 

authorization wait time:

10

reauthorization wait time:

10

authorization grace time:

600

operational wait time:

1

rekey wait time:

1

tek grace time:

600

authorization rej wait time: 60

kek state:

STATE_B_AUTH_WAIT

 

sid 4:

 

 

 

tek state: No resources assigned

Configuring the Cisco uBR900 Series Cable Access Routers 77

show controllers cable-modembpkm

Table 7 describes the fields shown in the display.

Table 7

show controllers cable-modembpkm Field Descriptions

 

 

 

Field

 

Description

 

 

authorization wait time

The number of seconds the Cisco uBR900 series waits for a reply after sending the

 

 

Authorization Request message to the CMTS.

 

 

reauthorization wait time

The number of seconds the Cisco uBR900 series waits for a reply after it has sent an

 

 

Authorization Request message to the CMTS in response to a reauthorization request or

 

 

an Authorization Invalid message from the CMTS.

 

 

authorization grace time

The number of seconds before the current authorization is set to expire that the grace

 

 

timer begins, signaling the Cisco uBR900 series to begin the reauthorization process.

 

 

operational wait time

The number of seconds the TEK state machine waits for a reply from the CMTS after

 

 

sending its initial Key Request for its SID’s keying material.

 

 

 

rekey wait time

 

The number of seconds the TEK state machine waits for a replacement key for this SID

 

 

after the TEK grace timer has expired and the request for a replacement key has been

 

 

made.

 

 

 

tek grace time

 

The number of seconds before the current TEK is set to expire that the TEK grace timer

 

 

begins, signaling the TEK state machine to request a replacement key.

 

 

authorization rej wait time

Number of seconds the Cisco uBR900 series waits before sending another

 

 

Authorization Request message to the CMTS after it has received an Authorization

 

 

Reject message.

 

 

 

kek state

 

The current state of the key encryption key that the CMTS uses to encrypt the traffic

 

 

encryption keys it sends to the Cisco uBR900 series.

 

 

 

tek state

 

The current state of the traffic encryption key state machine for the specified SID.

 

 

 

Related Commands

Command

Description

 

 

show controllers cable-modem

Displays high-levelcontroller information about a

 

Cisco uBR900 series cable access router.

 

 

show controllers cable-modem des

Displays information about the Data Encryption Standard

 

(DES) engine registers.

 

 

show controllers cable-modem filters

Displays the registers in the MAC hardware that are used for

 

filtering received frames.

 

 

show controllers cable-modem

Displays the mini-slotlookup table inside a Cisco uBR900

lookup-table

series.

 

 

show controllers cable-modem mac

Displays detailed MAC-layerinformation for a Cisco uBR900

 

series.

 

 

show controllers cable-modem phy

Displays the contents of the registers used in the downstream

 

physical hardware of the Cisco uBR900 series.

 

 

show controllers cable-modem tuner

Displays the settings for the upstream and downstream tuners

 

used by a Cisco uBR900 series.

 

 

78 Cisco IOS Release 12.0(7)T

show controllers cable-modemdes

show controllers cable-modemdes

To display information about the Data Encryption Standard (DES) engine registers, use the show controllers cable-modem des command in privileged EXEC mode.

show controllers cable-modemnumber des

Syntax Description

number

Controller number inside the Cisco uBR900 series.

Defaults

No default behavior or values.

Command Modes

Privileged EXEC

Command History

Release

Modification

11.3 NA

This command was introduced.

 

 

Examples

DES engine registers are displayed in the following example:

uBR924# show controllerscable-modem0 desdownstream des:

ds_des_key_table:

key 0: even 0, odd 0 key 1: even 0, odd 0 key 2: even 0, odd 0 key 3: even 0, odd 0

ds_des_cbc_iv_table: iv 0: even 0, odd 0 iv 1: even 0, odd 0 iv 2: even 0, odd 0 iv 3: even 0, odd 0

ds_des_sid_table:

sid_1=0x0000, sid_2=0x0000, sid_3=0x0000, sid_4=0x0000 ds_des_sid_enable=0x80, ds_des_ctrl=0x2E ds_des_sv=0x0F00

ds_unencrypted_length=0x0C upstream des:

us_des_key_table:

key 0: even 0, odd 0 key 1: even 0, odd 0 key 2: even 0, odd 0 key 3: even 0, odd 0

us_des_cbc_iv_table: iv 0: even 0, odd 0 iv 1: even 0, odd 0 iv 2: even 0, odd 0 iv 3: even 0, odd 0

Configuring the Cisco uBR900 Series Cable Access Routers 79

show controllers cable-modemdes

pb_req_bytes_to_minislots=0x10 us_des_ctrl=0x00, us_des_sid_1= 0x1234 ds_unencrypted_length=0x0C

Table 8 briefly describes some of the fields shown in the display. For more information, see the

Broadcom documentation for the BCM3300 chip.

Table 8

show controllers cable-modemdes Field Descriptions

 

 

 

Field

 

Description

 

 

 

ds_des_key_table

 

Table showing downstream DES keys.

 

 

ds_des_cbc_iv_table

Table of downstream DES Cipher Block Chaining mode information.

 

 

 

ds_des_sid_table

 

Table showing the SID values to be enabled for DES encryption.

 

 

 

ds_des_sid_enable

 

Controls which SID entries in the SID table are enabled for encryption. In the above

 

 

example, none of the entries are enabled for encryption.

 

 

 

ds_des_ctrl

 

Control register that controls the operating mode of the downstream DES engine.

 

 

 

ds_des_sv

 

DES security version register; the range of the version field in the Baseline Privacy

 

 

Interface (BPI) extended headers that will be accepted by the hardware. High byte is

 

 

upper limit, low byte is lower limit. The Cisco uBR900 will accept versions 0 to 15.

 

 

ds_unencrypted_length

Specifies the number of bytes that will be unencrypted at the beginning of the MAC

 

 

frame. 0x0C means the first 12 bytes are not encrypted, which is what the DOCSIS

 

 

Baseline Privacy specification calls for.

 

 

 

us_des_key_table

 

Table showing upstream DES keys.

 

 

us_des_cbc_iv_table

Table of upstream DES Cipher Block Chaining mode information.

 

 

 

us_des_ctrl

 

Control register that controls the operating mode of the upstream DES engine. The

 

 

value 0x24 means that the upstream is configured to enable decryption and to use CBC

 

 

mode.

 

 

 

Related Commands

Command

Description

 

 

show controllers cable-modem

Displays high-levelcontroller information about a

 

Cisco uBR900 series cable access router.

 

 

show controllers cable-modem bpkm

Displays information about the baseline privacy key

 

management exchange between the Cisco uBR900 series and

 

the CMTS.

 

 

show controllers cable-modem filters

Displays the registers in the MAC hardware that are used for

 

filtering received frames.

 

 

show controllers cable-modem

Displays the mini-slotlookup table inside a Cisco uBR900.

lookup-table

 

 

 

show controllers cable-modem mac

Displays detailed MAC-layerinformation for a Cisco uBR900.

 

 

show controllers cable-modem phy

Displays the contents of the registers used in the downstream

 

physical hardware of the Cisco uBR900 series.

 

 

show controllers cable-modem tuner

Displays the settings for the upstream and downstream tuners

 

used by a Cisco uBR900 series.

 

 

80 Cisco IOS Release 12.0(7)T

show controllers cable-modemfilters

show controllers cable-modemfilters

To display the registers in the MAC hardware that are used for filtering received frames, use the show controllers cable-modem filters command in privileged EXEC mode.

show controllers cable-modemnumber filters

Syntax Description

number

Controller number inside the Cisco uBR900 series.

Defaults

No default behavior or values.

Command Modes

Privileged EXEC

Command History

Release

Modification

11.3 NA

This command was introduced.

 

 

Usage Guidelines

Some of the filtering parameters are MAC hardware addresses, Service IDs (SIDs), and upstream channel IDs.

Configuring the Cisco uBR900 Series Cable Access Routers 81

show controllers cable-modemfilters

Examples

MAC and SID filter information is displayed in the following example:

uBR924# show controllerscable-modem0 filtersdownstream mac message processing:

ds_mac_da_filters:

filter_1=0010.7b43.aa01, filter_2=0000.0000.0000 filter_3=0000.0000.0000, filter_4=0000.0000.0000

ds_mac_da_filter_ctrl=0x71, ds_mac_msg_sof=0x0000 ds_mac_da_mc=01E02F00

map_parser_sids:

sid_1=0x0000, sid_2=0x0000, sid_3=0x0000, sid_4=0x0000 ds_mac_filter_ctrl=0x00, us_channel_id=0x0000 ds_pid=0x0000, mac_msg_proto_ver=FF 00 reg_rang_req_sid=0x0000

downstream data processing: ds_data_da_filter_table:

filter_1 0010.7b43.aa01, filter_2 0000.0000.0000 filter_3 0000.0000.0000, filter_4 0000.0000.0000

ds_data_da_filter_ctrl=0x61, ds_pdu_sof=0xDEAD ds_data_da_mc=01000000

upstream processing:

us_ctrl_status=0x04, Minislots per request=0x01 burst_maps:

map[0]=0 map[1]=0 map[2]=0 map[3]=0 bytes_per_minislot_exp=0x04

us_map_parser_minislot_adv=0x03, ticks_per_minislot=0x08, maint_xmit=0x0001 us_sid_table:

sid_1=0x0000, sid_2=0x0000, sid_3=0x0000, sid_4=0x0000 max_re_req=0x0010, rang_fifo=0x00

Table 9 briefly describes some of the fields shown in the display. For more information, see the

Broadcom documentation for the BCM3300 chip.

Table 9

show controllers cable-modemfilters Field Descriptions

 

 

 

Field

 

Description

 

 

 

ds_mac_da_filters

 

Shows the MAC address of the cable interface and the MAC address of any Ethernet

 

 

MAC it is bridging.

 

 

ds_mac_da_filter_ctrl

Downstream MAC filter control for data.

 

 

 

ds_mac_msg_sof

 

Downstream MAC message start of frame.

 

 

 

ds_mac_da_mc

 

Downstream MAC control filter for data.

 

 

 

map_parser_sids

 

Service IDs used for upstream bandwidth allocation.

 

 

 

ds_mac_filter_ctrl

 

Downstream MAC filter control for MAC messages.

 

 

 

us_channel_id

 

Upstream channel ID.

 

 

 

ds_pid

 

Downstream packet ID

 

 

mac_msg_proto_ver

Version of the MAC management protocol in use.

 

 

 

reg_rang_req_sid

 

Service ID (SID) field of the ranging request message.

 

 

ds_data_da_filter_table

Downstream data processing filter table.

 

 

ds_data_da_filter_ctrl

Downstream data processing filter control.

 

 

 

ds_pdu_sof

 

Downstream PDU start of frame.

 

 

 

ds_data_da_mc

 

Downstream data processing MAC control.

 

 

 

us_ctrl_status

 

Upstream control status.

 

 

 

82 Cisco IOS Release 12.0(7)T

 

 

 

show controllers cable-modemfilters

 

Table 9

show controllers cable-modemfilters Field Descriptions (continued)

 

 

 

 

 

Field

 

Description

 

 

 

 

Minislots per request

Length of each registration request in mini-slots.

 

 

 

 

 

burst_maps

 

Maps the burst profiles saved in the BCM3037 registers to interval usage codes

 

 

 

(IUCs).

 

 

 

 

bytes_per_minislot_exp

Number of bytes per expansion mini-slot.

 

 

 

 

 

ticks_per_minislot

 

Number of time ticks (6.25-microsecondintervals) in each upstreammini-slot.

 

 

 

 

 

maint_xmit

 

Number of initial maintenance transmit opportunities.

 

 

 

 

 

us_sid_table

 

Upstream service ID table.

 

 

 

 

 

max_re_req

 

Maximum number of registration re-requestsallowed.

 

 

 

 

 

rang_fifo

 

Number of ranging requests that can be held in the first-in-first-out(FIFO) buffer.

 

 

 

 

Related Commands

Command

Description

 

 

show controllers cable-modem

Displays high-levelcontroller information about a

 

Cisco uBR900 series cable access router.

 

 

show controllers cable-modem bpkm

Displays information about the baseline privacy key

 

management exchange between the Cisco uBR900 series and

 

the CMTS.

 

 

show controllers cable-modem des

Displays information about the Data Encryption Standard

 

(DES) engine registers.

 

 

show controllers cable-modem

Displays the mini-slotlookup table inside a Cisco uBR900.

lookup-table

 

 

 

show controllers cable-modem mac

Displays detailed MAC-layerinformation for a Cisco uBR900.

 

 

show controllers cable-modem phy

Displays the contents of the registers used in the downstream

 

physical hardware of the Cisco uBR900.

 

 

show controllers cable-modem tuner

Displays the settings for the upstream and downstream tuners

 

used by a Cisco uBR900.

 

 

Configuring the Cisco uBR900 Series Cable Access Routers 83

show controllers cable-modemlookup-table

show controllers cable-modemlookup-table

To display the mini-slotlookup table inside a Cisco uBR900 series, use theshow controllers cable-modem lookup-table command in privileged EXEC mode.

show controllers cable-modemnumber lookup-table

Syntax Description

number

Controller number inside the Cisco uBR900 series.

Defaults

No default behavior or values.

Command Modes

Privileged EXEC

Command History

Release

Modification

11.3 NA

This command was introduced.

 

 

Usage Guidelines

This command displays the details of the lookup table. The driver uses this table to convert the size of the packets that the Cisco uBR900 series wants to transmit into a bandwidth request to the CMTS in mini-slots.The contents of this table are affected by the upstream symbol rate that is negotiated between the CMTS and the cable access router.

Use this table to look up the packet size and determine how many mini-slotswill be needed.

84 Cisco IOS Release 12.0(7)T

show controllers cable-modemlookup-table

Examples

The mini-slotlookup table is displayed in the following example:

uBR924# show controllerscable-modem0lookup-table

Max Burst Size (minislots) = 0x6

Max Burst Length (bytes) = 0x4B

PHY Overhead Lookup Table:

000:01 06 06 06 06 06 06 06 06 06 06 06 06 06 06 06

010:06 06 06 06 06 06 06 06 06 06 06 06 06 06 06 06

020:06 06 06 06 06 06 06 06 06 06 06 06 06 06 06 06

030:06 06 06 06 06 06 06 06 06 06 06 06 06 06 06 06

040:06 06 06 06 06 06 06 06 06 06 06 06 10 10 10 10

050:10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10

060:10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10

070:10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10

080:10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10

090: 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 0A0: 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 0B0: 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 0C0: 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 0D0: 10 10 10 10 10 10 10 10 10 10 10 10 10 1F 1F 1F 0E0: 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 0F0: 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F

100:1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F

110:1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F

120:1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F

130:1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F

140:1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F

150:1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F

160:1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F

170:1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F

180:1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F

190: 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1A0: 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1F 1B0: 1F 1F 1F 1F 1F 1F 1F 1F 1F 2D 2D 2D 2D 2D 2D 2D 1C0: 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 1D0: 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 1E0: 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 1F0: 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D

200:2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D

210:2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D

220:2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D

230:2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D

240:2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D

250:2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D

260:2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D

270:2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D

280:2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D 2D

290: 2D 2D 2D 2D 2D 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 2A0: 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 2B0: 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 2C0: 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 2D0: 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 2E0: 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 2F0: 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C

300:3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C

310:3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C

320:3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C

330:3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C

340:3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C

350:3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C

360: 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C 3C

Configuring the Cisco uBR900 Series Cable Access Routers 85

show controllers cable-modemlookup-table

370:3C 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B

380:4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B

390: 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 3A0: 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 3B0: 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 3C0: 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 3D0: 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 3E0: 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 3F0: 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B

400:4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B

410:4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B

420:4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B

430:4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B

440:4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 4B 5A 5A 5A

450:5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A

460:5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A

470:5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A

480:5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A

490: 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 4A0: 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 4B0: 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 4C0: 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 4D0: 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 4E0: 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 4F0: 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A

500:5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A

510:5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A 5A

520:5A 5A 5A 5A 5A 5A 5A 5A 5A 68 68 68 68 68 68 68

530:68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68

540:68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68

550:68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68

560:68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68

570:68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68

580:68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68

590: 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 5A0: 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 5B0: 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 5C0: 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 5D0: 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 5E0: 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 5F0: 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68 68

600:68 68 68 68 68 77 77 77 77 77 77 77 77 77 77 77

610:77 77 77 77 77 77 77 77 77 77 77 77 77 77 77 77

620:77 77 77 77 77 77 77 77 77 77 77 77 77 77 77 77

630: 77 77 77 77 77 77 77 77 77 77 77 77 77 77 77 77

PHY Reverse Lookup Table:

00:0000 0000 0000 0000 0000 0000 004B 0000

08:0000 0000 0000 0000 0000 0000 0000 0000

10:00DC 00DC 00DC 00DC 00DC 00DC 00DC 00DC

18:00DC 00DC 00DC 00DC 00DC 00DC 00DC 01B8

20:01B8 01B8 01B8 01B8 01B8 01B8 01B8 01B8

28:01B8 01B8 01B8 01B8 01B8 0294 0294 0294

30:0294 0294 0294 0294 0294 0294 0294 0294

38:0294 0294 0294 0294 0370 0370 0370 0370

40:0370 0370 0370 0370 0370 0370 0370 0370

48:0370 0370 0370 044C 044C 044C 044C 044C

50:044C 044C 044C 044C 044C 044C 044C 044C

58:044C 044C 0528 0528 0528 0528 0528 0528

60:0528 0528 0528 0528 0528 0528 0528 0528

68:0604 0604 0604 0604 0604 0604 0604 0604

70:0604 0604 0604 0604 0604 0604 0604 06E0

78:06E0 06E0 06E0 06E0 06E0 06E0 06E0 06E0

80: 06E0 06E0 06E0 06E0 06E0 06E0 07BC 07BC

86 Cisco IOS Release 12.0(7)T

show controllers cable-modemlookup-table

88:07BC 07BC 07BC 07BC 07BC 07BC 07BC 07BC

90:07BC 07BC 07BC 07BC 07BC 0898 0898 0898

98: 0898 0898 0898 0898 0898 0898 0898 0898 A0: 0898 0898 0898 0974 0974 0974 0974 0974 A8: 0974 0974 0974 0974 0974 0974 0974 0974 B0: 0974 0974 0A50 0A50 0A50 0A50 0A50 0A50 B8: 0A50 0A50 0A50 0A50 0A50 0A50 0A50 0A50 C0: 0A50 0B2C 0B2C 0B2C 0B2C 0B2C 0B2C 0B2C C8: 0B2C 0B2C 0B2C 0B2C 0B2C 0B2C 0B2C 0B2C D0: 0C08 0C08 0C08 0C08 0C08 0C08 0C08 0C08 D8: 0C08 0C08 0C08 0C08 0C08 0C08 0CE4 0CE4 E0: 0CE4 0CE4 0CE4 0CE4 0CE4 0CE4 0CE4 0CE4 E8: 0CE4 0CE4 0CE4 0CE4 0CE4 0DC0 0DC0 0DC0 F0: 0DC0 0DC0 0DC0 0DC0 0DC0 0DC0 0DC0 0DC0 F8: 0DC0 0DC0 0DC0 0DC0 0E9C 0E9C 0E9C 0E9C

Related Commands

Command

Description

 

 

show controllers cable-modem

Displays high-levelcontroller information about a Cisco BR900

 

series cable access router.

 

 

show controllers cable-modem bpkm

Displays information about the baseline privacy key

 

management exchange between the Cisco uBR900 series and

 

the CMTS.

 

 

show controllers cable-modem des

Displays information about the Data Encryption Standard

 

(DES) engine registers.

 

 

show controllers cable-modem filters

.Displays the registers in the MAC hardware that are used for

 

filtering received frames.

 

 

show controllers cable-modem mac

Displays detailed MAC-layerinformation for a Cisco uBR900.

 

 

show controllers cable-modem phy

Displays the contents of the registers used in the downstream

 

physical hardware of the Cisco uBR900.

 

 

show controllers cable-modem tuner

Displays the settings for the upstream and downstream tuners

 

used by a Cisco uBR900.

 

 

Configuring the Cisco uBR900 Series Cable Access Routers 87

show controllers cable-modemmac

show controllers cable-modemmac

To display detailed MAC-layerinformation for a Cisco uBR900 series, use theshow controllers cable-modem mac command in privileged EXEC mode.

show controllers cable-modemnumber mac[errors| hardware| log| resets| state]

Syntax Description

number

Controller number inside the Cisco uBR900 series.

errors

(Optional) Displays a log of the error events that are reported to SNMP. This keyword

 

enables you to look at the error events without accessing a MIB.

hardware

(Optional) Displays all MAC hardware registers.

log

(Optional) Displays a history of MAC log messages, up to 1023 entries. This is the same

 

output that is displayed when using the debug cable-modem mac log command.

resets

(Optional) Extracts all of the reset causes out of the MAC log file and summarizes them

 

in a mini report.

state

(Optional) Displays a summary of the MAC state.

Defaults

No default behavior or values.

Command Modes

Privileged EXEC

Command History

Release

Modification

11.3 NA

This command was introduced.

 

 

Usage Guidelines

MAC log messages are written to a circular log file even when debugging is not turned on. These messages include timestamps, events, and information pertinent to these events. Use the show controllers cable-modem mac log command to view MAC log messages.

If the Cisco uBR900 series interface fails to come up or resets periodically, the MAC log will capture what happened. For example, if an address is not obtained from the DHCP server, an error is logged, initialization starts over, and the Cisco uBR900 series scans for a downstream frequency.

The most useful keywords for troubleshooting a Cisco uBR900 series are log,errors, andresets. SeeExample 1, Example 2, andExample 3.

88 Cisco IOS Release 12.0(7)T

show controllers cable-modemmac

Example 1

The following sample display shows the MAC log file for a cable-modeminterface that has successfully registered with the CMTS:

uBR924# show controllerscable-modem0 mac log

 

00:14:24:

864.124

CMAC_LOG_DRIVER_INIT_IDB_RESET

0x080B7430

00:14:24:

864.128

CMAC_LOG_LINK_DOWN

 

00:14:24:

864.132

CMAC_LOG_RESET_FROM_DRIVER

 

00:14:24:

864.134

CMAC_LOG_STATE_CHANGE

wait_for_link_up_state

00:14:24:

864.138

CMAC_LOG_LINK_UP

 

00:14:24:

864.142

CMAC_LOG_STATE_CHANGE

ds_channel_scanning_state

00:14:24:

864.270

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

81/453000000/855000000/6000000

00:14:24:

864.276

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

82/93000000/105000000/6000000

00:14:24:

864.280

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

83/111025000/117025000/6000000

00:14:24:

864.286

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

84/231012500/327012500/6000000

00:14:24:

864.290

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

85/333025000/333025000/6000000

00:14:24:

864.294

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

86/339012500/399012500/6000000

00:14:24:

864.300

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

87/405000000/447000000/6000000

00:14:24:

864.304

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

88/123012500/129012500/6000000

00:14:24:

864.310

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

89/135012500/135012500/6000000

00:14:24:

864.314

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

90/141000000/171000000/6000000

00:14:24:

864.320

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

91/219000000/225000000/6000000

00:14:24:

864.324

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

92/177000000/213000000/6000000

00:14:24:

864.330

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

93/55752700/67753300/6000300

00:14:24:

864.334

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

94/79753900/85754200/6000300

00:14:24:

864.340

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

95/175758700/211760500/6000300

00:14:24:

864.344

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

96/121756000/169758400/6000300

00:14:24:

864.348

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

97/217760800/397769800/6000300

00:14:24:

864.354

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

98/73753600/115755700/6000300

00:14:24:

864.358

CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

99/403770100/997799800/6000300

00:14:24:

864.364

CMAC_LOG_WILL_SEARCH_SAVED_DS_FREQUENCY

213000000

00:14:25:

865.450

CMAC_LOG_UCD_MSG_RCVD

1

00:14:25: %LINK-3-UPDOWN:Interfacecable-modem0,changed state to up

00:14:26:

866.200

CMAC_LOG_DS_64QAM_LOCK_ACQUIRED

213000000

00:14:26:

866.204

CMAC_LOG_DS_CHANNEL_SCAN_COMPLETED

 

00:14:26:

866.206

CMAC_LOG_STATE_CHANGE

wait_ucd_state

00:14:26: %LINEPROTO-5-UPDOWN:Line protocol on Interfacecable-modem0,changed state to down

00:14:27:

867.456

CMAC_LOG_UCD_MSG_RCVD

1

 

00:14:29:

869.470

CMAC_LOG_UCD_MSG_RCVD

1

 

00:14:29:

869.472

CMAC_LOG_ALL_UCDS_FOUND

 

 

00:14:29:

869.476

CMAC_LOG_STATE_CHANGE

wait_map_state

00:14:29:

869.480

CMAC_LOG_UCD_NEW_US_FREQUENCY

20000000

00:14:29:

869.484

CMAC_LOG_SLOT_SIZE_CHANGED

8

 

00:14:29:

869.564

CMAC_LOG_FOUND_US_CHANNEL

1

 

00:14:31:

871.484

CMAC_LOG_UCD_MSG_RCVD

1

 

00:14:31:

871.692

CMAC_LOG_MAP_MSG_RCVD

 

 

00:14:31:

871.694

CMAC_LOG_INITIAL_RANGING_MINISLOTS

40

 

00:14:31:

871.696

CMAC_LOG_STATE_CHANGE

ranging_1_state

00:14:31:

871.700

CMAC_LOG_RANGING_OFFSET_SET_TO

9610

 

00:14:31:

871.704

CMAC_LOG_POWER_LEVEL_IS

32.0

dBmV (commanded)

00:14:31:

871.708

CMAC_LOG_STARTING_RANGING

 

 

00:14:31:

871.710

CMAC_LOG_RANGING_BACKOFF_SET

0

 

00:14:31:

871.714

CMAC_LOG_RNG_REQ_QUEUED

0

 

00:14:32:

872.208

CMAC_LOG_RNG_REQ_TRANSMITTED

 

 

00:14:32:

872.216

CMAC_LOG_RNG_RSP_MSG_RCVD

 

 

00:14:32:

872.218

CMAC_LOG_RNG_RSP_SID_ASSIGNED

16

 

00:14:32:

872.222

CMAC_LOG_ADJUST_RANGING_OFFSET

2853

 

00:14:32:

872.224

CMAC_LOG_RANGING_OFFSET_SET_TO

12463

 

00:14:32:

872.228

CMAC_LOG_ADJUST_TX_POWER

8

 

00:14:32:

872.230

CMAC_LOG_POWER_LEVEL_IS

34.0

dBmV (commanded)

00:14:32:

872.234

CMAC_LOG_STATE_CHANGE

ranging_2_state

00:14:32:

872.238

CMAC_LOG_RNG_REQ_QUEUED

16

 

00:14:32:

872.848

CMAC_LOG_RNG_REQ_TRANSMITTED

 

 

00:14:32:

872.852

CMAC_LOG_RNG_RSP_MSG_RCVD

 

 

Configuring the Cisco uBR900 Series Cable Access Routers 89

show controllers cable-modemmac

00:14:32:

872.856

CMAC_LOG_RANGING_SUCCESS

 

00:14:32:

872.874

CMAC_LOG_STATE_CHANGE

dhcp_state

00:14:33:

873.386

CMAC_LOG_DHCP_ASSIGNED_IP_ADDRESS

188.188.1.62

00:14:33:

873.388

CMAC_LOG_DHCP_TFTP_SERVER_ADDRESS

4.0.0.32

00:14:33:

873.392

CMAC_LOG_DHCP_TOD_SERVER_ADDRESS

4.0.0.32

00:14:33:

873.396

CMAC_LOG_DHCP_SET_GATEWAY_ADDRESS

 

00:14:33:

873.398

CMAC_LOG_DHCP_TZ_OFFSET

60

00:14:33:

873.402

CMAC_LOG_DHCP_CONFIG_FILE_NAME

platinum.cm

00:14:33:

873.406

CMAC_LOG_DHCP_ERROR_ACQUIRING_SEC_SVR_ADDR

 

00:14:33:

873.410

CMAC_LOG_DHCP_COMPLETE

 

00:14:33:

873.536

CMAC_LOG_STATE_CHANGE

establish_tod_state

00:14:33:

873.546

CMAC_LOG_TOD_REQUEST_SENT

 

00:14:33:

873.572

CMAC_LOG_TOD_REPLY_RECEIVED

3140961992

00:14:33:

873.578

CMAC_LOG_TOD_COMPLETE

 

00:14:33:

873.582

CMAC_LOG_STATE_CHANGE

security_association_state

00:14:33:

873.584

CMAC_LOG_SECURITY_BYPASSED

 

00:14:33:

873.588

CMAC_LOG_STATE_CHANGE

configuration_file_state

00:14:33:

873.592

CMAC_LOG_LOADING_CONFIG_FILE

platinum.cm

00:14:34: %LINEPROTO-5-UPDOWN:Line protocol on Interfacecable-modem0,changed state to up

00:14:34:

874.728

CMAC_LOG_CONFIG_FILE_PROCESS_COMPLETE

 

00:14:34:

874.730

CMAC_LOG_STATE_CHANGE

registration_state

00:14:34:

874.734

CMAC_LOG_REG_REQ_MSG_QUEUED

 

00:14:34:

874.744

CMAC_LOG_REG_REQ_TRANSMITTED

 

00:14:34:

874.754

CMAC_LOG_REG_RSP_MSG_RCVD

 

00:14:34:

874.756

CMAC_LOG_COS_ASSIGNED_SID

1/16

00:14:34:

874.760

CMAC_LOG_RNG_REQ_QUEUED

16

00:14:34:

874.768

CMAC_LOG_REGISTRATION_OK

 

00

 

 

 

:14:34:

874.770 CMAC_LOG_REG_RSP_ACK_MSG_QUEUED

0

00:14:34:

874.774

CMAC_LOG_STATE_CHANGE

establish_privacy_state

00:14:34:

874.778

CMAC_LOG_PRIVACY_NOT_CONFIGURED

 

00:14:34:

874.780

CMAC_LOG_STATE_CHANGE

maintenance_state

00:14:34:

874.784

CMAC_LOG_REG_RSP_ACK_MESSAGE_EVENT

 

00:14:34:

874.788

CMAC_LOG_REG_RSP_ACK_MSG_SENT

 

If the DHCP server cannot not be reached, the error will look like this in the MAC log:

00:14:32:

872.874

CMAC_LOG_STATE_CHANGE

dhcp_state

00:14:33:

873.386

CMAC_LOG_RNG_REQ_TRANSMITTED

 

00:14:33:

873.388

CMAC_LOG_RNG_RSP_MSG_RCVD

 

00:14:33:

873.386

CMAC_LOG_RNG_REQ_TRANSMITTED

 

00:14:33:

873.392

CMAC_LOG_RNG_RSP_MSG_RCVD

 

00:14:33:

873.396

CMAC_LOG_WATCHDOG_TIMER

 

00:14:33:

873.398

CMAC_LOG_RESET_DHCP_WATCHDOG_EXPIRED

 

00:14:33:

873.402

CMAC_LOG_STATE_CHANGE

reset_interface_state

00:14:33:

873.406

CMAC_LOG_DHCP_PROCESS_KILLED

 

The fields in this display are explained in the section “Basic Troubleshooting” on page 23.

Example 2

MAC error log information is displayed in the following example, which is also reported via SNMP:

uBR924# show controllerscable-modem0 mac errors

 

 

74373.574

R02.0

No Ranging Response received.

T3

time-out.

74374.660

R02.0

No Ranging Response received.

T3

time-out.

74375.508

R02.0

No Ranging Response received.

T3

time-out.

74375.748

R02.0

No Ranging Response received.

T3

time-out.

74375.748

R03.0

Ranging Request Retries exhausted.

 

74376.112

R02.0

No Ranging Response received.

T3

time-out.

74376.354

R02.0

No Ranging Response received.

T3

time-out.

74376.778

R02.0

No Ranging Response received.

T3

time-out.

74377.442

R02.0

No Ranging Response received.

T3

time-out.

90 Cisco IOS Release 12.0(7)T

show controllers cable-modemmac

This output indicates that the Cisco uBR900 series acquired a downstream lock, successfully read a UCD, and successfully read a MAP. However, it was unable to communicate with the CMTS after ranging through all upstream transmit power levels. The Cisco uBR900 series tried to communicate with the CMTS 16 times without success, after which it reset the cable interface to try to find a better downstream frequency.

If the DHCP server could not be reached, the error would look like this in the MAC error display:

uBR924# show controllerscable-modem0 mac errors

 

 

 

 

497989.804

D01.0

Discover sent no Offer received.

No available DHCP Server.

498024.046

D01.0

Discover

sent

no

Offer

received.

No

available

DHCP

Server.

498058.284

D01.0

Discover

sent

no

Offer

received.

No

available

DHCP

Server.

Example 3

The show controllers cable-modem 0 mac resets command shows only the entries in the MAC log that begin with the fieldCMAC_LOG_RESET. Collectively presenting these fields provides you with a summary of the most recent reasons why the cable interface was reset.

Reset messages and brief explanations are included in the following examples and in Table 10; however, the reset messages inTable 10 do not commonly occur.

In the following example, the configuration file downloaded from the TFTP server could not be read. The file might not exist, or the file might have incorrect permissions.

uBR924# show controllerscable-modem0 mac resets

62526.114

CMAC_LOG_RESET_CONFIG_FILE_READ_FAILED

62564.368

CMAC_LOG_RESET_T4_EXPIRED

62677.178

CMAC_LOG_RESET_CONFIG_FILE_READ_FAILED

62717.462

CMAC_LOG_RESET_CONFIG_FILE_READ_FAILED

62757.746

CMAC_LOG_RESET_CONFIG_FILE_READ_FAILED

62796.000

CMAC_LOG_RESET_T4_EXPIRED

62908.808

CMAC_LOG_RESET_CONFIG_FILE_READ_FAILED

62949.092

CMAC_LOG_RESET_CONFIG_FILE_READ_FAILED

62989.380

CMAC_LOG_RESET_CONFIG_FILE_READ_FAILED

63029.662

CMAC_LOG_RESET_CONFIG_FILE_READ_FAILED

63069.944

CMAC_LOG_RESET_CONFIG_FILE_READ_FAILED

63110.228

CMAC_LOG_RESET_CONFIG_FILE_READ_FAILED

63148.484

CMAC_LOG_RESET_T4_EXPIRED

63261.296

CMAC_LOG_RESET_CONFIG_FILE_READ_FAILED

The following example shows that the DHCP server could not be reached, or that it took too long to respond.

uBR924# show controllerscable-modem0 mac resets

497989.804 CMAC_LOG_RESET_DHCP_WATCHDOG_EXPIRED 498024.046 CMAC_LOG_RESET_DHCP_WATCHDOG_EXPIRED 498058.284 CMAC_LOG_RESET_DHCP_WATCHDOG_EXPIRED

Configuring the Cisco uBR900 Series Cable Access Routers 91

show controllers cable-modemmac

The following example indicates that an event in the cable interface driver caused the interface to reset. This often occurs because a shut or clear command is currently being issued on the interface.

uBR924# show controllerscable-modem0 mac resets

527986.444 CMAC_LOG_RESET_FROM_DRIVER 528302.042 CMAC_LOG_RESET_FROM_DRIVER 528346.600 CMAC_LOG_RESET_FROM_DRIVER 528444.494 CMAC_LOG_RESET_FROM_DRIVER

Table 10

Possible but Uncommon Cable Interface Reset Causes

 

 

 

Message

 

Description

 

 

CMAC_LOG_RESET_CONFIG_FILE_PARSE_FAILED

The format of the DOCSIS configuration file acquired

 

 

from the TFTP server is not acceptable.

 

 

CMAC_LOG_RESET_LOSS_OF_SYNC

Synchronization with the CMTS has been lost (SYNC

 

 

messages are not being received).

 

 

CMAC_LOG_RESET_T4_EXPIRED

Maintenance ranging opportunities for this

 

 

Cisco uBR900 are not being received from the CMTS.

 

 

CMAC_LOG_RESET_DHCP_WATCHDOG_EXPIRED

The DHCP server took too long to respond.

 

 

CMAC_LOG_RESET_TOD_WATCHDOG_EXPIRED

The Time Of Day server took too long to respond.

 

 

CMAC_LOG_RESET_PRIVACY_WATCHDOG_EXPIRED

The baseline privacy exchange with the CMTS took too

 

 

long.

 

 

CMAC_LOG_RESET_CHANGE_US_WATCHDOG_EXPIRED

The Cisco uBR900 series was unable to transmit a

 

 

response to a UCC-REQmessage.

 

 

CMAC_LOG_RESET_SECURITY_WATCHDOG_EXPIRED

The “full security” exchange with the CMTS took too

 

 

long.

 

 

CMAC_LOG_RESET_CONFIG_FILE_WATCHDOG_EXPIRED

The TFTP server took too long to respond.

 

 

CMAC_LOG_RESET_ALL_FREQUENCIES_SEARCHED

All downstream frequencies to be searched have been

 

 

searched.

 

 

Note This message indicates that downstream

 

 

frequencies were found, but the Cisco uBR900 series

 

 

failed to acquire a downstream lock.

 

 

CMAC_LOG_RESET_T2_EXPIRED

Initial ranging opportunities are not being received.

 

 

CMAC_LOG_RESET_T3_RETRIES_EXHAUSTED

The CMTS failed too many times to respond to a

 

 

RNG-REQmessage.

 

 

Note After 16 T3 timeouts, the Cisco uBR900 series will

 

 

reset the cable interface.

 

 

CMAC_LOG_RESET_RANGING_ABORTED

The CMTS commanded the Cisco uBR900 series to abort

 

 

the ranging process.

 

 

CMAC_LOG_RESET_NO_MEMORY

The Cisco uBR900 series has run out of memory.

 

 

CMAC_LOG_RESET_CANT_START_PROCESS

The Cisco uBR900 series was unable to start an internal

 

 

process necessary to complete ranging and registration.

 

 

CMAC_LOG_RESET_CONFIG_FILE_READ_FAILED

The reading of the configuration file from the TFTP

 

 

server failed.

 

 

Note The file might not exist, or it might have incorrect

 

 

permissions.

 

 

CMAC_LOG_RESET_AUTHENTICATION_FAILURE

The Cisco uBR900 series failed authentication as

 

 

indicated in a REG-RSPmessage from the CMTS.

 

 

 

92 Cisco IOS Release 12.0(7)T

 

 

 

show controllers cable-modemmac

 

Table 10

Possible but Uncommon Cable Interface Reset Causes (continued)

 

 

 

 

 

Message

 

Description

 

 

 

 

CMAC_LOG_RESET_SERVICE_NOT_AVAILABLE

The CMTS has failed the Cisco uBR900 series’

 

 

 

registration because a required or requested class of

 

 

 

service is not available.

 

 

 

 

CMAC_LOG_RESET_T6_RETRIES_EXHAUSTED

The CMTS failed too many times to respond to a

 

 

 

REG-REQmessage.

 

 

 

 

CMAC_LOG_RESET_MAINTENANCE_WATCHDOG_DRIVER

The Cisco uBR900 series MAC layer failed to detect a

 

 

 

change in the interface driver.

 

 

 

 

CMAC_LOG_RESET_NET_ACCESS_MISSING

The Network Access parameter is missing from the

 

 

 

DOCSIS configuration file.

 

 

 

 

CMAC_LOG_RESET_FAILED_WRITE_ACCESS_CONTROL

The Cisco uBR900 series was unable to set the Write

 

 

 

Access Control for an SNMP parameter as specified by

 

 

 

the DOCSIS configuration file.

 

 

 

 

CMAC_LOG_RESET_DHCP_FAILED

The DHCP server did not respond with all the required

 

 

 

values. The required values are: IP address, network

 

 

 

mask, TFTP server IP address, TOD server IP address,

 

 

 

DOCSIS configuration file name, and time zone offset.

 

 

 

 

CMAC_LOG_RESET_CANT_START_DS_TUNER_PRCESS

The Cisco uBR900 series was unable to start the internal

 

 

 

process used to manage the downstream tuner.

 

 

 

 

CMAC_LOG_RESET_TOO_MANY_DS_LOCKS_LOST

Downstream QAM/FEC lock has been lost too many

 

 

 

times.

 

 

 

 

CMAC_LOG_RESET_NO_SEND_TO_DS_TUNER_PROCESS

The Cisco uBR900 series MAC-layerprocess was unable

 

 

 

to communicate with the downstream tuner management

 

 

 

process.

 

 

 

 

CMAC_LOG_RESET_DS_TUNER_WATCHDOG

The downstream tuner process failed to report its

 

 

 

continuing operation for a long period of time.

 

 

 

 

CMAC_LOG_RESET_UNABLE_TO_SET_MIB_OBJECT

The Cisco uBR900 series was unable to set an SNMP

 

 

 

parameter as specified by the DOCSIS configuration file.

 

 

 

 

CMAC_LOG_RESET_MIB_OBJECT_PROCESS_WATCHDOG

The internal MIB object took too long to process the

 

 

 

entries in the DOCSIS configuration file.

 

 

 

 

Configuring the Cisco uBR900 Series Cable Access Routers 93

show controllers cable-modemmac

Example 4

The following example display for the show controllers cable-modem 0 mac hardware command shows the detailed configuration of the interface driver and theMAC-layerhardware. The most interesting bit is the station address (hardware address). The MIB statistics reflect the MAC hardware counters for various events, but these counters are typically reset every few seconds, so their contents are not accurate in this display.

uBR924# show controllerscable-modem0 mac hardware

PLD VERSION: 32

BCM3300 unit 0, idb 0x200EB4, ds 0x82D4748, regaddr = 0x800000, reset_mask 0x80

station address 0010.7b43.aa01 default station address 0010.7b43.aa01 MAC mcfilter 01E02F00 data mcfilter 01000000

buffer

size 1600

 

RX data PDU ring with 32 entries at 0x201D40

rx_head = 0x201D40

(0), rx_p = 0x82D4760 (0)

00

pak=0x82DF844

buf=0x227F1A status=0x80 pak_size=0

01

pak=0x82E0BF4

buf=0x22C56A status=0x80 pak_size=0

02

pak=0x82DF454

buf=0x22710A status=0x80 pak_size=0

03

pak=0x82DF64C

buf=0x227812 status=0x80 pak_size=0

04

pak=0x82E0024

buf=0x229B3A status=0x80 pak_size=0

05

pak=0x82DBF2C

buf=0x21B332 status=0x80 pak_size=0

06

pak=0x82DFE2C

buf=0x229432 status=0x80 pak_size=0

07

pak=0x82E0FE4

buf=0x22D37A status=0x80 pak_size=0

08

pak=0x82DF064

buf=0x2262FA status=0x80 pak_size=0

09pak=0x82DEC74 buf=0x2254EA status=0x80 pak_size=0

10pak=0x82DEA7C buf=0x224DE2 status=0x80 pak_size=0

11pak=0x82DE884 buf=0x2246DA status=0x80 pak_size=0

12pak=0x82DE68C buf=0x223FD2 status=0x80 pak_size=0

13pak=0x82DE494 buf=0x2238CA status=0x80 pak_size=0

14pak=0x82DE29C buf=0x2231C2 status=0x80 pak_size=0

15pak=0x82DE0A4 buf=0x222ABA status=0x80 pak_size=0

16pak=0x82DDEAC buf=0x2223B2 status=0x80 pak_size=0

17pak=0x82DDCB4 buf=0x221CAA status=0x80 pak_size=0

18pak=0x82DDABC buf=0x2215A2 status=0x80 pak_size=0

19pak=0x82DD8C4 buf=0x220E9A status=0x80 pak_size=0

20pak=0x82DD6CC buf=0x220792 status=0x80 pak_size=0

21pak=0x82DD4D4 buf=0x22008A status=0x80 pak_size=0

22pak=0x82DD2DC buf=0x21F982 status=0x80 pak_size=0

23pak=0x82DD0E4 buf=0x21F27A status=0x80 pak_size=0

24pak=0x82DCEEC buf=0x21EB72 status=0x80 pak_size=0

25pak=0x82DCCF4 buf=0x21E46A status=0x80 pak_size=0

26pak=0x82DCAFC buf=0x21DD62 status=0x80 pak_size=0

27pak=0x82DC904 buf=0x21D65A status=0x80 pak_size=0

28pak=0x82DC70C buf=0x21CF52 status=0x80 pak_size=0

29pak=0x82DC514 buf=0x21C84A status=0x80 pak_size=0

30pak=0x82DC31C buf=0x21C142 status=0x80 pak_size=0

31pak=0x82DC124 buf=0x21BA3A status=0xA0 pak_size=0 RX MAC message ring with 8 entries at 0x201E80

rx_head_mac = 0x201EB0 (6), rx_p_mac = 0x82D480C (6)

00pak=0x82E0DEC buf=0x22CC72 status=0x80 pak_size=0

01pak=0x82E021C buf=0x22A242 status=0x80 pak_size=0

02pak=0x82E060C buf=0x22B052 status=0x80 pak_size=0

03pak=0x82E11DC buf=0x22DA82 status=0x80 pak_size=0

04pak=0x82DFC34 buf=0x228D2A status=0x80 pak_size=0

05pak=0x82E09FC buf=0x22BE62 status=0x80 pak_size=0

06pak=0x82DEE6C buf=0x225BF2 status=0x80 pak_size=0

07pak=0x82DFA3C buf=0x228622 status=0xA0 pak_size=0

94 Cisco IOS Release 12.0(7)T

show controllers cable-modemmac

TX BD ring with 8 entries at 0x201FB8, tx_count = 0 tx_head = 0x201FB8 (0), head_txp = 0x82D4888 (0) tx_tail = 0x201FB8 (0), tail_txp = 0x82D4888 (0)

00 pak=0x000000 buf=0x200000 status=0x00 pak_size=0

01 pak=0x000000 buf=0x200000 status=0x00 pak_size=0

02 pak=0x000000 buf=0x200000 status=0x00 pak_size=0

03 pak=0x000000 buf=0x200000 status=0x00 pak_size=0

04 pak=0x000000 buf=0x200000 status=0x00 pak_size=0

05 pak=0x000000 buf=0x200000 status=0x00 pak_size=0

06 pak=0x000000 buf=0x200000 status=0x00 pak_size=0

07 pak=0x000000 buf=0x200000 status=0x20 pak_size=0 TX PD ring with 8 entries at 0x202038, tx_count = 0

tx_head_pd = 0x202038 (0) tx_tail_pd = 0x202038 (0)

00 status=0x00 bd_index=0x0000 len=0x0000 hdr_len=0x0000 ehdr: 00 00 00 2E FF FF

01 status=0x00 bd_index=0x0001 len=0x0000 hdr_len=0x0000 ehdr: 00 00 00 2E FF FF

02 status=0x00 bd_index=0x0002 len=0x0000 hdr_len=0x0000 ehdr: 00 00 00 2E FF FF

03 status=0x00 bd_index=0x0003 len=0x0000 hdr_len=0x0000 ehdr: 00 00 00 2E FF FF

04 status=0x00 bd_index=0x0004 len=0x0000 hdr_len=0x0000 ehdr: 00 00 00 2E 00 00

05 status=0x00 bd_index=0x0005 len=0x0000 hdr_len=0x0000 ehdr: 00 00 00 2E 00 00

06 status=0x00 bd_index=0x0006 len=0x0000 hdr_len=0x0000 ehdr: 00 00 00 00 00 00

07 status=0x20 bd_index=0x0007 len=0x0000 hdr_len=0x0000 ehdr: 00 00 00 00 00 00

MIB Statistics

DS fifo full = 0, Rerequests = 0

DS mac msg overruns = 0, DS data overruns = 0 Qualified maps = 0, Qualified syncs = 0

CRC fails = 0, HDR chk fails = 0 Data pdus = 0, Mac msgs = 0 Valid hdrs = 0

BCM3300 Registers: downstream dma:

ds_data_bd_base=0x001D40, ds_mac_bd_base=0x001E80 ds_data_dma_ctrl=0x98, ds_mac_dma_ctrl=0x98 ds_dma_data_index=0x0000, ds_dma_msg_index=0x0000

upstream dma:

us_bd_base=0x001FB8, us_pd_base=0x002038 us_dma_ctrl=0x00, us_dma_tx_start=0x00

global control and status: global_ctrl_status=0x00

interrupts:

irq_pend=0x0018, irq_mask=0x00E7 timing recovery circuit:

loop_enable=0x00, minislot_divisor=0x00 K0_ctrl=0x06, K1_ctrl=0x07, acq_threshhold=0x01 err_threshhold=0x04, timeout_threshold=0xFF nco_bias=0x4F7004F7, ranging_offset=0x00000000 ts_err=0x00, sync_valid=0x00, delta_F=0x00 timeout_err=0x00

spi:

dynamic_ctrl=0x09, static_ctr=0x9F, autonomous=0x01 irq_ack=0x00, spi_cmd=0x51, spi_addr=0x11 spi_data= FF/00/00/00/00/00/00

Configuring the Cisco uBR900 Series Cable Access Routers 95

show controllers cable-modemmac

burst profiles: profile 0:

01 19 1D 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

profile 1:

01 19 1D 03 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

profile 2:

01 19 1D 04 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

profile 3:

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

Most of the fields in this display are described in Table 15, show dhcp server Field Descriptions. Table 11 describes the MIB statistics shown in the display.

Table 11 show controllers cable-modemMIB Statistics Field Descriptions

Field

Description

DS fifo full

Number of times the downstream receive buffer on the Cisco uBR900 series has

 

become full.

 

 

Rerequests

Number of registration requests sent by the Cisco uBR900 series to the CMTS.

 

 

DS mac msg overruns

Number of times the DMA controller has had a downstream MAC message and there

 

were no free MAC message buffer descriptors to accept the message.

 

 

DS data overruns

Number of times the DMA controller has had downstream data and there were no free

 

data PDU buffer descriptors to accept the data.

 

 

Qualified maps

Number of valid MAP messages received by the Cisco uBR900 series.

 

 

Qualified syncs

Number of times the Cisco uBR900 series has received synchronization with the

 

downstream channel.

 

 

CRC fails

Number of cyclic redundancy checksums generated by the far-enddevice that did not

 

match the checksums calculated from the message portions of the packets received.

 

 

HDR check fails

Number of cyclic redundancy checksums generated by the far-enddevice that did not

 

match the checksums calculated from the MAC headers of the packets received. The

 

MAC header CRC is a 16-bitHeader Check Sequence (HCS) field that ensures the

 

integrity of the MAC header even in a collision environment.

 

 

Data pdus

Total number of data PDUs (protocol data units) of all types received by the cable

 

interface.

 

 

Mac msgs

Number of MAC messages received by the cable interface.

 

 

Valid hdrs

Number of valid MAC headers received by the cable interface.

 

 

Below the MIB statistics in the show controllers cable-modem 0 mac hardware display, the BCM3300 registers section shows the DMA locations of the indicated processing routines of the Broadcom 3220 MAC chip within the Cisco uBR900 series.

96 Cisco IOS Release 12.0(7)T

show controllers cable-modemmac

Example 5

The show controllers cable-modem mac state command summarizes the state of the cable MAC layer and provides a list of downstream search frequency bands and the order in which they are searched. If the cable MAC layer is in thewait_for_link_up_state, the information shown in the display corresponds to the last time the interface was up. This allows useful information to be acquired from this display even though the modem has not been able to range and register. The normal operational state of the interface is themaintenance_state.

uBR924# show controllercable-modem0 mac state

MAC State:

 

 

maintenance_state

Ranging SID:

 

 

5

Registered:

 

 

TRUE

Privacy Established:

 

TRUE

MIB Values:

 

 

 

Mac Resets:

 

0

 

Sync lost:

 

0

 

Invalid Maps:

 

0

 

Invalid UCDs:

 

0

 

Invalid Rng Rsp:

0

 

Invalid Reg Rsp:

0

 

T1

Timeouts:

 

0

 

T2

Timeouts:

 

0

 

T3

Timeouts:

 

4

 

T4

Timeouts:

 

0

 

Range Aborts:

 

0

 

DS ID:

 

 

1

DS Frequency:

 

 

663000000

DS Symbol Rate:

 

 

5056941

DS QAM Mode

 

 

64QAM

DS Search:

 

 

 

88

453000000

855000000

6000000

8993000000 105000000 6000000

90111250000 117250000 6000000

91231012500 327012500 6000000

92333015000 333015000 6000000

93339012500 399012500 6000000

94405000000 447000000 6000000

95123015000 129015000 6000000

96135012500 135012500 6000000

97141000000 171000000 6000000

98219000000 225000000 6000000

99177000000 213000000 6000000

US ID:

1

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

US Frequency:

20000000

 

 

 

 

 

 

 

 

 

 

 

 

 

 

US Power Level:

34.0 (dBmV)

 

 

 

 

 

 

 

 

 

 

 

 

 

US Symbol Rate:

1280000

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Ranging Offset:

12460

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Mini-SlotSize:

8

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Change Count:

4

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Preamble Pattern:

CC CC CC CC CC CC CC CC

CC

CC CC CC CC CC 0D 0D

 

 

A9

17

D9

C3

52

2F

B3

86

A4

5F

67

0D

48

BE CE 1A

 

91

7D

9C

35

22

FB 38 6A

45

F6

70

D4

8B

EC E1 A9

 

17

D9

C3

52

2F

B3

86

A4

5F

67

0D

48

BE CE 1A 91

 

F3

F3

F3

F3

F3

F3

F3

F3

F3

F3

F3

F3

F3

F3

F3

F3

 

F3

F3

F3

F3

F3

F3

F3

F3

F3

F3

F3

F3

33

F7

33

F7

 

88

84

04

4C

C4

84

C0

0C

44

08

08

CC 8C 0C

80

48

 

88

40

44

CC 48 4C 00 C4

40

80

8C

C8

C0

C8

04

88

Configuring the Cisco uBR900 Series Cable Access Routers 97

show controllers cable-modemmac

Burst Descriptor

0:

 

Interval Usage Code:

1

Modulation Type:

 

1

Differential Encoding:

2

Preamble Length:

 

64

Preamble Value Offset:

56

FEC Error Correction:

0

FEC Codeword Info Bytes:

16

Scrambler Seed:

 

338

Maximum Burst Size:

1

Guard Time Size:

 

8

Last Codeword Length:

1

Scrambler on/off:

1

Burst Descriptor

1:

 

Interval Usage Code:

3

Modulation Type:

 

1

Differential Encoding:

2

Preamble Length:

 

128

Preamble Value Offset:

0

FEC Error Correction:

5

FEC Codeword Info Bytes:

34

Scrambler Seed:

 

338

Maximum Burst Size:

0

Guard Time Size:

 

48

Last Codeword Length:

1

Scrambler on/off:

1

Burst Descriptor

2:

 

Interval Usage Code:

4

Modulation Type:

 

1

Differential Encoding:

2

Preamble Length:

 

128

Preamble Value Offset:

0

FEC Error Correction:

5

FEC Codeword Info Bytes:

34

Scrambler Seed:

 

338

Maximum Burst Size:

0

Guard Time Size:

 

48

Last Codeword Length:

1

Scrambler on/off:

1

Burst Descriptor

3:

 

Interval Usage Code:

5

Modulation Type:

 

1

Differential Encoding:

2

Preamble Length:

 

72

Preamble Value Offset:

48

FEC Error Correction:

5

FEC Codeword Info Bytes:

75

Scrambler Seed:

 

338

Maximum Burst Size:

0

Guard Time Size:

 

8

Last Codeword Length:

1

Scrambler on/off:

1

Config File:

 

 

Network Access:

 

TRUE

Vendor ID:

 

0.240.30

Baseline Privacy:

 

Auth. Wait Timeout:

10

Reauth. Wait Timeout:

10

Auth. Grace Time:

600

Op. Wait Timeout:

1

Retry Wait Timeout:

1

TEK Grace Time:

600

Auth. Reject Wait Time:

60

98 Cisco IOS Release 12.0(7)T

show controllers cable-modemmac

COS 1:

 

 

Assigned SID:

5

 

Max Downstream Rate:

4000000

Max Upstream Rate:

2000000

Upstream Priority:

7

 

Min Upstream Rate:

100000

Max Upstream Burst:

12

 

Privacy Enable:

TRUE

Ranging Backoff Start:

0

(at initial ranging)

Ranging Backoff End:

4

(at initial ranging)

Data Backoff Start:

0

(at initial ranging)

Data Backoff End:

4

(at initial ranging)

IP Address:

0.0.0.0

Net Mask:

0.0.0.0

TFTP Server IP Address:

223.255.254.254

Time Server IP Address:

188.188.1.5

Config File Name:

muck/ebuell/tftp/cm_conf

Time Zone Offset:

-28800

Table 12 describes the fields shown in the display.

Table 12

show controllers cable-modemMAC State Field Descriptions

 

 

 

Field

 

Description

 

 

 

MAC State

 

Current operational state of the MAC layer of the Cisco uBR900 series.

 

 

 

Ranging SID

 

Service ID used for ranging requests.

 

 

 

Registered

 

Indicates whether or not the Cisco uBR900 is currently registered with the CMTS.

 

 

Privacy Established

Indicates whether or not keys for baseline privacy have been exchanged between the

 

 

Cisco uBR900 series and the CMTS, establishing privacy.

 

 

 

Mac Resets

 

Number of times the Cisco uBR900 series reset or initialized this interface.

 

 

 

Sync lost

 

Number of times the Cisco uBR900 series lost synchronization with the downstream

 

 

channel.

 

 

 

Invalid Maps

 

Number of times the Cisco uBR900 series received invalid MAP messages.

 

 

 

Invalid UCDs

 

Number of times the Cisco uBR900 series received invalid UCD messages.

 

 

 

Invalid Rng Rsp

 

Number of times the Cisco uBR900 series received invalid ranging response

 

 

messages.

 

 

 

Invalid Reg Rsp

 

Number of times the Cisco uBR900 series received invalid registration response

 

 

messages.

 

 

 

T1 Timeouts

 

Number of timeouts caused by the Cisco uBR900 series not receiving a valid

 

 

upstream channel descriptor (UCD) from the CMTS within the specified time.

 

 

 

T2 Timeouts

 

Number of timeouts caused by the Cisco uBR900 series not receiving a maintenance

 

 

broadcast for ranging opportunities from the CMTS within a specified time.

 

 

 

T3 Timeouts

 

Number of timeouts caused by the Cisco uBR900 series not receiving a response

 

 

within a specified time from the CMTS to a RNG-REQmessage during initial

 

 

maintenance.

 

 

 

T4 Timeouts

 

Number of timeouts caused by the Cisco uBR900 series not receiving a response

 

 

within a specified time from the CMTS to a periodic maintenance request.

 

 

 

Range Aborts

 

Number of times the ranging process was aborted by the CMTS.

 

 

 

DS ID

 

Identifier of the downstream channel on which this MAC management message has

 

 

been transmitted. This identifier is arbitrarily chosen by the CMTS and is only

 

 

unique within the MAC-sublayerdomain.

 

 

 

Configuring the Cisco uBR900 Series Cable Access Routers 99

show controllers cable-modemmac

Table 12

show controllers cable-modemMAC State Field Descriptions (continued)

 

 

 

Field

 

Description

 

 

 

DS Frequency

 

Downstream frequency acquired by the Cisco uBR900 series during its last

 

 

initialization sequence.

 

 

 

DS Symbol Rate

 

Downstream frequency in symbols per second.

 

 

 

DS QAM Mode

 

Downstream modulation scheme being used by the Cisco uBR900 series.

 

 

 

DS Search

 

Frequency bands scanned by the Cisco uBR900 series when searching for a

 

 

downstream channel. The Cisco uBR900 series’ default frequency bands correspond

 

 

to the North American EIA CATV channel plan for 6 MHz channel slots between 90

 

 

MHz and 858 MHz.

 

 

 

US ID

 

Identifier of the upstream channel to which this MAC management message refers.

 

 

This identifier is arbitrarily chosen by the CMTS and is only unique within the

 

 

MAC-sublayerdomain.

 

 

 

US Frequency

 

Transmission frequency used by the Cisco uBR900 series in the upstream direction.

 

 

 

US Power Level

 

Transmit power level of the Cisco uBR900 series in the upstream direction.

 

 

 

US Symbol Rate

 

Upstream frequency in symbols per second.

 

 

 

Ranging Offset

 

Delay correction (in increments of 6.25 µs/64) applied by the Cisco uBR900 series to

 

 

the CMTS upstream frame time derived at the Cisco uBR900 series. Used to

 

 

synchronize the upstream transmissions in the time division multiple access

 

 

(TDMA) scheme, this value is roughly equal to the round-tripdelay of the

 

 

Cisco uBR900 series from the CMTS.

 

 

 

Mini-SlotSize

 

Size T of the mini-slotfor this upstream channel in units of the timebase tick of

 

 

6.25 µs. Allowable values are 2, 4, 8, 16, 32, 64, or 128.

 

 

 

Change Count

 

Incremented by 1 by the CMTS whenever any of the values of this channel descriptor

 

 

change. If the value of this count in a sebsequent upstream channel descriptor (UCD)

 

 

remains the same, the Cisco uBR900 series can quickly decide that the remaining

 

 

fields have not changed, and may be able to disregard the remainder of the message.

 

 

 

Preamble Pattern

 

Byte pattern used for the preamble.

 

 

 

Burst Descriptor:

 

A compound type/length/value (TLV) encoding that defines, for each type of

 

 

upstream usage interval, the physical-layercharacteristics that are to be used during

 

 

that interval. Each burst descriptor is given an identifying number.

Interval Usage Code

Each upstream transmit burst belongs to a class which is given a number called the

 

 

IUC (interval usage code). Bandwidth MAP messages are used by IUC codes to

 

 

allocate upstream time slots. The following types are currently defined:

 

 

1. Request: bandwidth request slot

 

 

2. Request/Data: bandwidth request or data slot

 

 

3. Initial Maintenance: initial link registration contention slot

 

 

4. Station Maintenance: link keep-aliveslot

 

 

5. Short Data Grant: short data burst slot

 

 

6. Long Data Grant: long data burst slot

 

 

Modulation Type

Upstream modulation format. (1 = QPSK; 2 = 16QAM)

 

 

Differential Encoding

Indicates whether or not differential encoding is used. (1 = yes; 2 = no)

 

 

 

Preamble Length

 

Length of the preamble in bits. This value must be an integral number of symbols—a

 

 

multiple of 2 for QPSK; a multiple of 4 for 16QAM.

 

 

FEC Error Correction

Length of the forward error correction in bytes. The range is 0-10bytes; a value of 0

 

 

implies no forward error correction.

 

 

FEC Codeword Info Bytes

Number of information bytes in the FEC codeword.

 

 

 

100 Cisco IOS Release 12.0(7)T

show controllers cable-modemmac

Table 12 show controllers cable-modemMAC State Field Descriptions (continued)

Field

Description

Scrambler Seed

15-bitseed value loaded at the beginning of each burst after the register has been

 

cleared. Not used if scrambler is off.

 

 

Maximum Burst Size

Maximum number of mini-slotsthat can be transmitted during this burst type. When

 

the interval type is Short Data Grant, this value must be greater than 0. If this value is

 

0, the burst size is limited elsewhere.

 

 

Guard Time Size

Amount of time in symbols between the center of the last symbol of a burst and the

 

center of the first symbol of the preamble of an immediately following burst in an

 

upstream transmission from the Cisco uBR900 series to the CMTS.

 

 

Last Codeword Length

Indicates whether or not the length of the last codeword is fixed or shortened.

 

(1 = fixed; 2 = shortened)

 

 

Scrambler on/off

Indicates whether or not a scrambler is enabled in the upstream modulator.

 

(1 = on; 2 = off)

 

 

Network Access

Indicates whether or not the Cisco uBR900 series has access to the HFC network.

 

 

Vendor ID

Unique identifier specifying the cable modem manufacturer.

 

 

Auth. Wait Timeout

Number of seconds the Cisco uBR900 series waits for a reply after sending the

 

Authorization Request message to the CMTS.

 

 

Reauth. Wait Timeout

Number of seconds the Cisco uBR900 series waits for a reply after it has sent an

 

Authorization Request message to the CMTS in response to a reauthorization request

 

or an Authorization Invalid message from the CMTS.

 

 

Auth. Grace Time

Number of seconds before the current authorization is set to expire that the grace

 

timer begins, signaling the Cisco uBR900 series to begin the reauthorization process.

 

 

Op. Wait Timeout

Number of seconds the TEK state machine waits for a reply from the CMTS after

 

sending its initial Key Request for its SID’s keying material.

 

 

Retry Wait Timeout

Number of seconds the TEK state machine waits for a replacement key for this SID

 

after the TEK grace timer has expired and the request for a replacement key has been

 

made.

 

 

TEK Grace Time

Number of seconds before the current TEK is set to expire that the TEK grace timer

 

begins, signaling the TEK state machine to request a replacement key.

 

 

Auth. Reject Wait Time

Number of seconds the Cisco uBR900 series waits before sending another

 

Authorization Request message to the CMTS after it has received an Authorization

 

Reject message.

 

 

Assigned SID

Service ID assigned by the CMTS for the corresponding service class.

 

 

Max Downstream Rate

Maximum downstream rate in bits per second that the CMTS is permitted to forward

 

to CPE unicast MAC addresses learned or configured as mapping to this

 

Cisco uBR900. (This does not include MAC packets addressed to broadcast or

 

multicast MAC addresses.)

 

 

Max Upstream Rate

Maximum upstream rate in bits per second that the Cisco uBR900 series is permitted

 

to forward to the RF network. This includes packet PDU data packets addressed to

 

broadcast or multicast addresses.

 

 

Upstream Priority

Relative priority assigned to this service class for data transmission in the upstream

 

channel. Higher numbers indicate higher priority.

 

 

Min Upstream Rate

Date rate in bits per second that will be guaranteed to this service class on the

 

upstream channel.

 

 

Max Upstream Burst

Maximum transmit burst in bytes allowed for this service class on the upstream

 

channel.

 

 

Privacy Enable

Indicates whether or not Baseline Privacy is enabled for this service class.

 

 

Configuring the Cisco uBR900 Series Cable Access Routers 101

show controllers cable-modemmac

Table 12

show controllers cable-modemMAC State Field Descriptions (continued)

 

 

 

Field

 

Description

 

 

Ranging Backoff Start

Initial back-offwindow for initial ranging contention, expressed as a power of 2.

 

 

Valid values are from 0 to 15.

 

 

Ranging Backoff End

Final back-offwindow for initial ranging contention, expressed as a power of 2.

 

 

Valid values are from 0 to 15.

 

 

 

Data Backoff Start

 

Initial back-offwindow for contention data and requests, expressed as a power of 2.

 

 

Valid values are from 0 to 15.

 

 

 

Data Backoff End

 

Final back-offwindow for contention data and requests, expressed as a power of 2.

 

 

Valid values are from 0 to 15.

 

 

 

IP Address

 

IP address of the cable interface.

 

 

 

Net Mask

 

Subnet mask of the cable interface.

 

 

TFTP Server IP Address

IP address of the CMTS TFTP server.

 

 

Time Server IP Address

IP address of the CMTS Time of Day (TOD) server.

 

 

 

Config File Name

 

Name of the configuration file that is downloaded from the TFTP server to provide

 

 

the Cisco uBR900 series with operational parameters.

 

 

 

Time Zone Offset

 

Correction received from the DHCP server to synchronize the Cisco uBR900 series

 

 

time clock with the CMTS.

 

 

 

Related Commands

Command

Description

 

 

show controllers cable-modem

Displays high-levelcontroller information about a

 

Cisco uBR900 series cable access router.

 

 

show controllers cable-modem bpkm

Displays information about the baseline privacy key

 

management exchange between the Cisco uBR900 series and

 

the CMTS.

 

 

show controllers cable-modem des

Displays information about the Data Encryption Standard

 

(DES) engine registers.

 

 

show controllers cable-modem filters

.Displays the registers in the MAC hardware that are used for

 

filtering received frames.

 

 

show controllers cable-modem

Displays the mini-slotlookup table inside a Cisco uBR900

lookup-table

series.

 

 

show controllers cable-modem phy

Displays the contents of the registers used in the downstream

 

physical hardware of the Cisco uBR900 series.

 

 

show controllers cable-modem tuner

Displays the settings for the upstream and downstream tuners

 

used by a Cisco uBR900 series.

 

 

102 Cisco IOS Release 12.0(7)T

show controllers cable-modemphy

show controllers cable-modemphy

To display the contents of the registers used in the downstream physical hardware of the

Cisco uBR900 series cable access router, use the show controllers cable-modem phy command in privileged EXEC mode.

show controllers cable-modemphy{receive| transmit}

Syntax Description

receive

Displays all receiver registers in the downstream physical hardware.

transmit

Displays all transmitter registers in the upstream physical hardware.

Defaults

No default behavior or values.

Command Modes

Privileged EXEC

Command History

Release

Modification

11.3 NA

This command was introduced.

 

 

Usage Guidelines

To understand the output from this command, consult the Broadcom specifications for the BCM3116 and BCM3037 chips.

Examples

Physical receive registers are displayed in the following example:

uBR924# show controllerscable-modem0 phy receive

BCM3116 Receiver Registers: Chip ID = C2C1

rstctl=

frzctl=20

qamctl=1B

lmsctl=0B

tpctl=00

fmtctl=24

ffectl=3F

irqsts=09

irqmask=00

stoscm=9E

rstctr=00

frzctl2=46

dvctl=30

idepth=55 eqlctl=00

tstctl=02 berctl=00 clkset=00

tunset=00

tunctl=03

 

 

 

 

FFC

coefficient registers:

 

 

F0=0067FFBC

F1=FF880080

F2=00C1FEFB

F3=FF75019D

F4=00C5FD89

F5=FF6D0485

F6=FC95F690

F7=2D280000

DFE

coefficient registers:

 

 

D00=0636031E

D01=FBDD0314

D02=0077FD39

D03=001B00C6

D04=0024FF74

D05=0015007E

D06=000CFFC4

D07=FFC0004B

D08=0044FFF6

D09=FFE00019

D10=00190005

D11=FFD3FFAD

D12=FFD3FFE0

D13=001A000A

D14=FFF3FFED

D15=0008FFFD

D16=FFFC0024

D17=0023FFDF

D18=0029FFFF

D19=000D001E

D20=00020017

D21=00250001

D22=0007FFF4

D23=FFF60014

Configuring the Cisco uBR900 Series Cable Access Routers 103

show controllers cable-modemphy

ldsft=B0EE

ldsnre=0098AF

ldif=0D004E

ldbbi=00000000

ldbbq=00000000

ldali=032E00

ldaii=E62AF2

ldbrfo=705A05

ldbri=F9CDC200

lddrfo=007E7D

lddri=007EF0

 

FEC correctable error count: 0

FEC uncorrectable error count: 0

Bit Error Rate Count: 0

Physical transmit registers are displayed in the following example:

uBR924# show controllers

cable-modem0 phy transmit

BCM3037 Transmitter Registers:

 

part_id

= 3037

rev_id

= 01

test_mode

= 00

test_input

= 00

test_misc

= 2009

rst

= 00

power

= 0000

power_2

= 00

port

= 6F

pll

= F7

map

= 66

mod

= 28

tx_oen_bdly

= 14

tx_oen_edly = C8

prbs_cfg

= 00C000

baud

= 1A36E3

burst

= 0000

if_freq

= 200000

dac

= 37

tx_config

= 00

burst

config 0

: prbs_init

 

= FFFFFF

 

rs

 

= 343E

 

 

 

 

 

 

fec

 

 

 

= 00

 

 

qam

 

= 01

 

 

 

 

 

 

pream_len

 

= 0018

 

 

offset

= 0000

burst

config 1

: prbs_init

 

= FFFFFE

 

rs

 

= 033B

 

 

 

 

 

 

fec

 

 

 

= 1C

 

 

qam

 

= 65

 

 

 

 

 

 

pream_len

 

= 0000

 

 

offset

= 0000

burst

config 2

: prbs_init

 

= FFFFFE

 

rs

 

= 033B

 

 

 

 

 

 

fec

 

 

 

= 1D

 

 

qam

 

= 65

 

 

 

 

 

 

pream_len

 

= 0000

 

 

offset

= 0000

burst

config 3

: prbs_init

 

= FFFFFE

 

rs

 

= 033B

 

 

 

 

 

 

fec

 

 

 

= 1E

 

 

qam

 

= 65

burst

config 4

: prbs_init

 

= FFFFFE

 

rs

 

= 033B

 

 

 

 

 

 

fec

 

 

 

= 1F

 

 

qam

 

= 65

 

 

 

 

 

 

pream_len

 

= 0000

 

 

offset

= 0000

burst

config 5

: prbs_init

 

= FFFFFE

 

rs

 

= 033B

 

 

 

 

 

 

fec

 

 

 

= 0F

 

 

qam

 

= 66

 

 

 

 

 

 

pream_len

 

= 0000

 

 

offset

= 0000

Eq Coeff:

 

 

 

 

 

 

 

 

 

 

 

 

 

 

00

00

00

00

00

00

00

00

00

00

00

00

00

00

00

00

 

Preamble

values:

 

 

 

 

 

 

 

 

 

 

 

CC CC

CC

CC CC

0D

0D

CC CC CC CC CC CC CC CC 0D

 

04

25

01

01

01

01

02

01

02

03

02

00

40

04

02

00

 

40

05

01

00

06

01

10

07

02

01

52

08

01

01

09

01

 

08

0A

01

01

0B

01

02

04

25

03

01

01

01

02

01

02

 

03

02

00

50

04

02

00

30

05

01

00

06

01

22

07

02

 

01

52

08

01

00

09

01

30

0A

01

01

0B

01

02

04

25

 

04

01

01

01

02

01

02

03

02

00

40

04

02

00

40

05

 

01

00

06

01

22

07

02

01

52

08

01

00

09

01

30 0A

 

104 Cisco IOS Release 12.0(7)T

 

 

show controllers cable-modemphy

Related Commands

 

 

 

 

 

Command

Description

 

 

 

 

show controllers cable-modem

Displays high-levelcontroller information about a

 

 

Cisco uBR900 series cable access router.

 

 

 

 

show controllers cable-modem bpkm

Displays information about the baseline privacy key

 

 

management exchange between the Cisco uBR900 series and

 

 

the CMTS.

 

 

 

 

show controllers cable-modem des

Displays information about the Data Encryption Standard

 

 

(DES) engine registers.

 

 

 

 

show controllers cable-modem filters

.Displays the registers in the MAC hardware that are used for

 

 

filtering received frames.

 

 

 

 

show controllers cable-modem

Displays the mini-slotlookup table inside a Cisco uBR900

 

lookup-table

series.

 

 

 

 

show controllers cable-modem mac

Displays detailed MAC-layerinformation for a Cisco uBR900

 

 

series.

 

 

 

 

show controllers cable-modem tuner

Displays the settings for the upstream and downstream tuners

 

 

used by a Cisco uBR900 series.

 

 

 

Configuring the Cisco uBR900 Series Cable Access Routers 105

show controllers cable-modemtuner

show controllers cable-modemtuner

To display the settings for the upstream and downstream tuners used by a Cisco uBR900 series cable access router, use the show controllers cable-modem tuner command in privileged EXEC mode.

show controllers cable-modemtuner

Syntax Description

There are no key words or arguments for this command.

Defaults

No default behavior or values.

Command Modes

Privileged EXEC

Command History

Release

Modification

11.3 NA

This command was introduced.

 

 

Examples

Typical Cisco uBR900 series tuner settings are displayed in the following example. See Table 13 for output field possibilities and descriptions.

uBR924# show controllerscable-modem0 tuner

Tuner: status=0x00

Rx: tuner_freq 507000000, symbol_rate 5360736, local_freq 11520000 snr_estimate 17488, ber_estimate 0, lock_threshold 26000

QAM not in lock, FEC not in lock, qam_mode QAM_64

Tx: tx_freq 20000000, power_level 0x3E, symbol_rate 1280000

106 Cisco IOS Release 12.0(7)T

 

 

 

show controllers cable-modemtuner

 

Table 13

show controllers cable-modemtuner Field Descriptions

 

 

 

 

 

Field

Description

 

 

 

 

 

tuner_freq

Indicates the current downstream frequency.

 

 

 

 

symbol_rate

Indicates the downstream symbol rate in symbols per second.

 

 

 

 

local_freq

Frequency on which the transmitter and tuner communicate.

 

 

 

 

snr_estimate

Signal to noise estimate in dB X 1000.

 

 

 

 

ber_estimate

Bit error rate estimate (always 0).

 

 

 

 

lock_threshold

Minimum signal-to-noiseratio (SNR) that the Cisco uBR900 series will accept as a valid

 

 

lock.

 

 

 

 

 

QAM status

Indicates if QAM/FEC lock has been acquired and the modulation mode in use.

 

 

 

 

tx_freq

Upstream frequency sent to the Cisco uBR900 series by the CMTS in the UCD message.

 

 

 

 

power_level

Transmit power level as set in the hardware, given as a hexadecimal value. The units are

 

 

unique to the hardware used. Use the show controllerscable-modem0 mac state

 

 

command to see the power level in dBmV.

 

 

 

 

symbol_rate

Indicates the upstream symbol rate in symbols per second that is negotiated

 

 

between the CMTS and the cable access router.

 

 

 

 

Related Commands

 

 

 

 

 

 

 

Command

 

Description

 

 

 

 

show controllers cable-modem

Displays high-levelcontroller information about a

 

 

 

Cisco uBR900 series cable access router.

 

 

 

 

show controllers cable-modem bpkm

Displays information about the baseline privacy key

 

 

 

management exchange between the Cisco uBR900 series and

 

 

 

the CMTS.

 

 

 

 

show controllers cable-modem des

Displays information about the Data Encryption Standard

 

 

 

(DES) engine registers.

 

 

 

 

show controllers cable-modem filters

.Displays the registers in the MAC hardware that are used for

 

 

 

filtering received frames.

 

 

 

 

show controllers cable-modem

Displays the mini-slotlookup table inside a Cisco uBR900

 

lookup-table

 

series.

 

 

 

 

show controllers cable-modem mac

Displays detailed MAC-layerinformation for a Cisco uBR900

 

 

 

series.

 

 

 

 

show controllers cable-modem phy

Displays the contents of the registers used in the downstream

 

 

 

physical hardware of the Cisco uBR900 series.

 

 

 

 

Configuring the Cisco uBR900 Series Cable Access Routers 107

show dhcp

show dhcp

To display the current DHCP settings on point-to-pointinterfaces, enter theshow dhcp command from privileged EXEC mode.

show dhcp {lease| server}

Syntax Description

lease

Shows DHCP addresses leased from a server.

server

Shows known DHCP servers.

Defaults

No default behavior or values.

Command Modes

Privileged EXEC

Command History

Release

Modification

11.3 NA

This command was introduced.

 

 

Usage Guidelines

You can use this command on any point-to-pointtype of interface that uses DHCP for temporary IP address allocation.

Examples

Following is sample output for the show dhcp lease command:

uBR924# show dhcp lease

Temp IP addr: 188.188.1.40 for peer on Interface: cable-modem0Temp sub net mask: 0.0.0.0

DHCP Lease server: 4.0.0.32, state: 3 Bound DHCP transaction id: 2431

Lease: 3600 secs, Renewal: 1800 secs, Rebind: 3150 secs Temp default-gatewayaddr: 188.188.1.1

Next timer fires after: 00:58:01

Retry count: 0 Client-ID:0010.7b43.aa01

Table 14 describes the significant fields shown in the display.

108 Cisco IOS Release 12.0(7)T

show dhcp

Table 14

show dhcp lease Field Descriptions

 

 

 

Field

 

Description

 

 

 

Temp IP addr

 

IP address leased from the DHCP server for the cable access router interface.

 

 

Temp subnet mask

Temporary subnet mask assigned to the cable access router interface.

 

 

DHCP Lease server

IP address of the DHCP server that assigned an IP address to this client.

 

 

 

state

 

Current state of this client (the cable access router interface). Possible states are Bound,

 

 

Renew, or Rebinding. For descriptions of these states, see RFC 2131.

 

 

DHCP transaction id

Unique number established by the Cisco uBR900 series before the first request message

 

 

is sent to the DHCP server. The same transaction id is used as long as the lease keeps

 

 

getting renewed and is valid. If a new “discover” message is sent, a new transaction id is

 

 

used.

 

 

 

Lease

 

Time (in seconds) for which the leased IP address is valid; the duration of the lease.

 

 

 

Renewal

 

Time interval (in seconds) from address assignment until the client transitions to the

 

 

renewing state. When the renewal (T1) time expires, the client sends a unicast

 

 

dhcprequest message to the server to extends its lease. The default value of this timer is

 

 

0.5 times the duration of the lease.

 

 

 

Rebind

 

Time interval (in seconds) from address assignment until the client transitions to the

 

 

rebinding state and sends a broadcast dhcprequest message to any DHCP server to

 

 

extends its lease. The default value of this timer (T2) is 0.875 times the duration of the

 

 

lease.

 

 

Temp default-gatewayaddr

IP address of the router closest to this client on the network.

 

 

Next timer fires after

Time in hours, minutes, and seconds until the next timer expires.

 

 

 

Retry count

 

Number of times the client has sent any message to the DHCP server --most likely a

 

 

request message to extend its lease. When the lease is renewed, the Retry count is reset

 

 

to 0.

 

 

 

Client-ID

 

MAC address (with optional media type code) that uniquely identifies the client on the

 

 

subnet for binding lookups.

 

 

 

Following is sample output for the show dhcp server command:

uBR924# show dhcp server

 

 

 

DHCP server: ANY (255.255.255.255)

 

 

 

Leases:

1

 

 

 

 

Offers:

1

Requests: 2

Acks:

1

Naks: 0

Declines: 0

Releases: 0

Bad:

0

 

TFTP Server Name: SOHOSERVER

 

 

 

TIME0: 1.2.0.250,

TIME1: 0.0.0.0

 

 

 

Subnet: 255.255.255.0

 

 

 

Table 15 describes the significant fields shown in the display.

Table 15

show dhcp server Field Descriptions

 

 

Field

Description

 

 

DHCP server

MAC address used by the DHCP server.

 

 

Leases

Number of current leased IP addresses.

 

 

Offers

Number of offers for an IP address sent to a proxy-clientfrom the server.

 

 

Requests

Number of requests for an IP address to the server.

 

 

Configuring the Cisco uBR900 Series Cable Access Routers 109

show dhcp

Table 15

show dhcp server Field Descriptions (continued)

 

 

 

Field

 

Description

 

 

 

Acks

 

Number of ‘acknowledge’ messages sent by the server to the proxy-client.

 

 

 

Naks

 

Number of ‘not acknowledge’ messages sent by the server to the proxy-client.

 

 

 

Declines

 

Number of offers from the server that have been declined by the proxy-client.

 

 

 

Releases

 

Number of times IP addresses have been relinquished gracefully by the client.

 

 

 

Bad

 

Number of bad packets received due to wrong length, wrong field type, or other causes.

 

 

TFTP Server Name

Name (if any) configured for the server providing TFTP downloads to the cable modem.

 

 

 

TIME0

 

IP address of the primary Time of Day (TOD) server.

 

 

 

TIME1

 

IP address of the secondary Time of Day (TOD) server.

 

 

 

Subnet

 

Subnet containing the DHCP server.

 

 

 

Related Commands

Command

Description

 

 

cable-modem voip best-effort

Allows voice traffic to be transmitted on the upstream via

 

best effort rather than by assigning it a higher priority class

 

of service.

 

 

show bridge cable-modem

Ddisplays bridging information for a Cisco uBR900 series

 

cable access router.

 

 

show interfaces cable-modem

Displays information about the cable interface on the

 

Cisco uBR900 series cable access router.

 

 

110 Cisco IOS Release 12.0(7)T

show interfaces cable-modem

show interfaces cable-modem

To display information about the Cisco uBR900 series cable access router’s cable interface, enter the show interfaces cable-modem command from either user EXEC mode or privileged EXEC mode.

show interfaces cable-modemnumber [accounting| counters| crb| irb| type]

Syntax Description

number

Cable access router interface number.

accounting

(Optional) Displays the number of packets of each protocol type that has been sent

 

through the cable access router interface.

counters

(Optional) Shows MIB counters on the cable interface.

crb

(Optional) Displays concurrent routing and bridging information for each interface

 

that has been configured for routing or bridging. This option does not really apply to

 

the Cisco uBR900 series; it is included because it is part of the subsystem that

 

provides DOCSIS-compliantbridging. For more information, refer to theBridging

 

and IBM Networking Command Reference.

irb

(Optional) Displays integrated routing and bridging information for each interface

 

that has been configured for routing or bridging. This option does not really apply to

 

the Cisco uBR900 series; it is included because it is part of the subsystem that

 

provides DOCSIS-compliantbridging. For more information, refer to theBridging

 

and IBM Networking Command Reference.

type

(Optional) Designed to display information about virtual LANs associated with the

 

interface; however, this option is not supported on the Cisco uBR900 series.

Defaults

No default behavior or values.

Command Modes

User EXEC or privileged EXEC

Command History

Release

Modification

11.3 NA

This command was introduced.

 

 

Usage Guidelines

When this command is entered without a keyword, general information about the cable interface is displayed.

Configuring the Cisco uBR900 Series Cable Access Routers 111

show interfaces cable-modem

Examples

Traffic passing through the cable access router interface is shown in the following example:

uBR924# show interfacescable-modem0cable-modem0 is up, line protocol is up

Hardware is BCM3300, address is 0050.7366.2439 (bia 0050.7366.2439) Internet address is 5.2.0.11/16

MTU 1500 bytes, BW 27000 Kbit, DLY 1000 usec, reliability 255/255, txload 1/255, rxload 1/255

Encapsulation DOCSIS, loopback not set Keepalive set (10 sec)

ARP type:ARPA, ARP Timeout 04:00:00

Last input 00:00:00, output 00:00:00, output hang never Last clearing of "show interface" counters 00:08:40 Queueing strategy:fifo

Output queue 40/40, 52787 drops; input queue 0/75, 0 drops 5 minute input rate 2000 bits/sec, 2 packets/sec

5 minute output rate 94000 bits/sec, 154 packets/sec

1074 packets input, 418472 bytes, 0 no buffer

Received 19 broadcasts, 0 runts, 0 giants, 0 throttles

0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort 78771 packets output, 6326786 bytes, 0 underruns

0 output errors, 0 collisions, 0 interface resets

0 output buffer failures, 0 output buffers swapped out

Table 16 describes the significant fields shown in the display.

Table 16

show interfaces cable-modemField Descriptions

 

 

 

Field

 

Description

 

 

cable-modem0is up

Indicates that the interface is currently active. “Disabled” indicates the interface

 

 

has received more than 5000 errors in one keepalive interval (10 seconds by

 

 

default if keepalive is set); “administratively down” indicates the interface has

 

 

been taken down by an administrator.

 

 

line protocol is up

Indicates that the software processes that handle the line protocol believe the

 

 

interface is usable.

 

 

 

Hardware

 

Hardware type and MAC address.

 

 

Internet address

Internet address followed by the shorthand notation for the subnet mask.

 

 

 

MTU

 

Maximum Transmission Unit (equivalent of the maximum packet size) for the

 

 

interface.

 

 

 

BW

 

Bandwidth of the interface in kilobits per second.

 

 

 

DLY

 

Delay of the interface in microseconds.

 

 

 

reliability

 

Reliability of the interface, expressed as a fraction of 255, calculated as an

 

 

exponential average over a 5-minuteperiod. (255/255 equals 100% reliability.)

 

 

 

tx load/rx load

 

Load on the interface caused by transmitting and receiving, expressed as a

 

 

fraction of 255, calculated as an exponential average over a 5 minute period.

 

 

Encapsulation/loopback/keepalive

Encapsulation method assigned to the interface.

 

 

 

loopback

 

Indicates whether or not loopback is set.

 

 

 

keepalive

 

Indicates whether or not keepalives are set.

 

 

 

ARP type

 

Type of Address Resolution Protocol configured for the interface.

 

 

 

ARP Timeout

 

Number of hours, minutes, and seconds an ARP cache entry will stay in the

 

 

cache.

 

 

 

112 Cisco IOS Release 12.0(7)T

show interfaces cable-modem

Table 16 show interfaces cable-modemField Descriptions (continued)

Field

Description

Last input/output

Number of hours, minutes, and seconds since the last packet was successfully

 

received/transmitted by the interface.

 

 

output hang

Number of hours, minutes, and seconds since the interface was last reset because

 

of a transmission that took too long. When the number of hours in any of the

 

“Last..” fields exceeds 24, the number of days and hours is displayed. If the field

 

overflows, asterisks are printed.

 

 

Last clearing of “show interface”

Time at which the counters that measure cumulative statistics (such as number of

counters

bytes transmitted and received) shown in this report were last reset to zero. Note

 

that variables that might affect routing (for example, load and reliability) are not

 

cleared when the counters are cleared.

 

*** indicates the elapsed time is too large to be displayed.

 

0:00:00 indicates the counters were cleared more than 231 milliseconds (and less

 

than 232 milliseconds) ago.

Queueing strategy

Type of queueing strategy in effect on the interface.

 

 

Output queue/drops

Number of packets in the output queue followed by the size of the queue and the

 

number of packets dropped due to a full queue.

 

 

input queue/drops

Number of packets in the input queue followed by the size of the queue and the

 

number of packets dropped due to a full queue.

 

 

5 minute input rate

Average number of bits and packets received and transmitted per second in the

5 minute output rate

last 5 minutes. If the interface is not in promiscuous mode, it senses network

 

traffic it sends and receives (rather than all network traffic).

 

The 5-minuteinput and output rates should be used only as an approximation of

 

traffic per second during a given 5-minuteperiod. These rates are exponentially

 

weighted averages with a time constant of 5 minutes. A period of four time

 

constants must pass before the average will be within two percent of the

 

instantaneous rate of a uniform stream of traffic over that period.

 

 

packets input

Total number of error-freepackets received by the system.

 

 

bytes input

Total number of bytes, including data and MAC encapsulation, in the error-free

 

packets received by the system.

 

 

no buffer

Number of received packets discarded because there was no buffer space in the

 

main system. Compare with ignored count. Broadcast storms on Ethernet

 

networks and bursts of noise on serial lines are often responsible for no input

 

buffer events.

 

 

Received broadcasts

Total number of broadcast or multicast packets received by the interface.

 

 

runts

Number of packets discarded because they were smaller than the medium’s

 

minimum packet size. For example, any Ethernet packet less than 64 bytes is

 

considered a runt.

 

 

giants

Number of packets discarded because they were larger than the medium’s

 

maximum packet size. For example, any Ethernet packet larger than 1518 bytes

 

is considered a giant.

 

 

throttles

Number of times the receiver on the port was disabled, possibly due to buffer or

 

processor overload.

 

 

input errors

Includes runts, giants, no buffer, CRC, frame, overrun, and ignored counts. Other

 

input-relatederrors can also cause the input errors count to be increased, and

 

some datagrams may have more than one error; therefore, this sum may not

 

balance with the sum of enumerated input error counts.

 

 

Configuring the Cisco uBR900 Series Cable Access Routers 113

show interfaces cable-modem

Table 16

show interfaces cable-modemField Descriptions (continued)

 

 

 

Field

 

Description

 

 

 

CRC

 

Number of cyclic redundancy checksums generated by the originating LAN

 

 

station or far-enddevice that do not match the checksum calculated from the data

 

 

received. On a LAN, this usually indicates noise or transmission problems on the

 

 

LAN interface or the LAN bus itself. A high number of CRCs is usually the

 

 

result of collisions or a station transmitting bad data.

 

 

 

frame

 

Number of packets received incorrectly, having a CRC error and a noninteger

 

 

number of octets. On a LAN, this is usually the result of collisions or a

 

 

malfunctioning Ethernet device.

 

 

 

overrun

 

Number of times the receiver hardware was unable to hand received data to a

 

 

hardware buffer because the input rate exceeded the receiver’s ability to handle

 

 

the data.

 

 

 

ignored

 

Number of received packets ignored by the interface because the interface

 

 

hardware ran low on internal buffers. These buffers are different from the system

 

 

buffers mentioned previously in the buffer description. Broadcast storms and

 

 

bursts of noise can cause the ignored count to be increased.

 

 

 

abort

 

Number of packets whose receipt was aborted.

 

 

 

packets output

 

Total number of messages transmitted by the system.

 

 

 

bytes

 

Total number of bytes, including data and MAC encapsulation, transmitted by

 

 

the system.

 

 

 

underruns

 

Number of times the transmitter has been running faster than the router can

 

 

handle.

 

 

 

output errors

 

Sum of all errors that prevented the final transmission of datagrams out of the

 

 

interface being examined. Note that this may not balance with the sum of the

 

 

enumerated output errors, as some datagrams might have more than one error,

 

 

and others might have errors that do not fall into any of the specifically tabulated

 

 

categories.

 

 

 

collisions

 

Number of messages retransmitted due to an Ethernet collision. This is usually

 

 

the result of an overextended LAN (Ethernet or transceiver cable too long, more

 

 

than two repeaters between stations, or too many cascaded multiport

 

 

transceivers). A packet that collides is counted only once in output packets.

 

 

 

interface resets

 

Number of times an interface has been completely reset. This can happen if

 

 

packets queued for transmission were not sent within several seconds. On a serial

 

 

line, this can be caused by a malfunctioning modem that is not supplying the

 

 

transmit clock signal, or by a cable problem. If the system notices that the carrier

 

 

detect line of a serial interface is up, but the line protocol is down, it periodically

 

 

resets the interface in an effort to restart it. Interface resets can also occur when

 

 

an interface is looped back or shut down.

 

 

output buffer failures

Number of times the output buffer has failed.

 

 

output buffers swapped out

Number of times the output buffer has been swapped out.

 

 

 

114 Cisco IOS Release 12.0(7)T

show interfaces cable-modem

To display the number of packets and bytes of each protocol type passing through the cable access router interface, use the accounting option with theshow interface cable-modem command:

uBR924# show interfacecable-modem0 accounting

cable-modem0

 

 

 

 

Protocol

Pkts In

Chars In

Pkts Out

Chars Out

IP

545

185502

159

90240

Trans. Bridge

3878

964995

12597

1611142

ARP

73

3066

86

4128

Table 17 describes the fields shown in this display.

Table 17

show interfaces cable-modemAccounting Descriptions

 

 

Field

Description

 

 

Protocol

List of protocols operating on the cable-modeminterface.

 

 

Pkts In

Number of packets of each protocol received on the interface.

 

 

Chars In

Number of bytes of each protocol received on the interface.

 

 

Pkts Out

Number of packets of each protocol transmitted on the interface.

 

 

Chars Out

Number of bytes of cach protocol transmitted on the interface.

 

 

MIB counters on the cable interface are displayed in the next example:

uBR924# show intcable-modem0 counters

Cable specific counters:

 

Ranging requests sent

:

50982

Downstream FIFO full

:

0

Re-requests

:

7277

DS MAC Message Overruns:

0

DS Data Overruns

:

0

Received MAPs

:

254339485

Received Syncs

:

53059555

Message CRC failures

:

0

Header CRC failures

:

1394

Data PDUs

:

5853

DS MAC messages

:

307861745

Valid Headers

:

307869065

Sync losses

:

0

Pulse losses

:

1

BW request failures

:

6

Table 18 describes the counters shown in this display.

Table 18

show interfaces cable-modemCounters Descriptions

 

 

 

Field

 

Description

 

 

Ranging requests sent

Number of ranging requests sent by the Cisco uBR900 series to the CMTS.

 

 

Downstream FIFO full

Number of times the downstream input first-infirst-out(FIFO) buffer became full on

 

 

the Cisco uBR900 series.

 

 

 

Re-requests

 

Number of times a bandwidth request generated by the Cisco uBR900 series was not

 

 

responded to by the CMTS.

 

 

DS MAC Message Overruns

Number of times the Cisco uBR900 series’s DMA controller had a downstream MAC

 

 

message and there were no free MAC message buffer descriptors to accept the

 

 

message.

 

 

 

Configuring the Cisco uBR900 Series Cable Access Routers 115

show interfaces cable-modem

Table 18

show interfaces cable-modemCounters Descriptions (continued)

 

 

 

Field

 

Description

 

 

DS Data Overruns

Number of times the Cisco uBR900 series’s DMA controller had downstream data

 

 

and there were no free data PDU buffer descriptors to accept the data.

 

 

Received MAPs

Number of times a MAP message passed all filtering requirements and was received

 

 

by the Cisco uBR900 series.

 

 

Received Syncs

Number of times a timestamp message was received by the Cisco uBR900 series.

 

 

Message CRC failures

Number of times a MAC message failed a cyclic redundancy (CRC) check.

 

 

Header CRC failures

Number of times a MAC header failed its 16-bitCRC check. The MAC header CRC

 

 

is a 16-bitHeader Check Sequence (HCS) field that ensures the integrity of the MAC

 

 

header even in a collision environment.

 

 

 

Data PDUs

 

Total number of data PDUs (protocol data units) of all types received by the

 

 

Cisco uBR900 series.

 

 

DS MAC messages

Number of MAC messages received by the Cisco uBR900 series.

 

 

 

Valid Headers

 

Number of valid headers received by the Cisco uBR900 series, including PDU

 

 

headers, MAC headers, and headers only.

 

 

 

Sync losses

 

Number of times the Cisco uBR900 series lost timebase sync with the CMTS.

 

 

 

Pulse losses

 

Number of times the Cisco uBR900 series did not receive expected timestamp

 

 

messages from the CMTS.

 

 

BW request failures

Number of times the Cisco uBR900 series sent the maximum number of re-requests

 

 

for bandwidth allocation and the request was still not granted.

 

 

 

Information about routing and bridging protocols and filtering on the cable access router interface is displayed in the following example:

uBR924# show intcable-modem0 crb

cable-modem0

Bridged protocols on cable-modem0:ip

Software MAC address filter on cable-modem0

 

Hash Len

Address

Matches

Act

Type

0x00:

0

ffff.ffff.ffff

3877

RCV Physical broadcast

0x2A:

0

0900.2b01.0001

0

RCV DEC spanning tree

0x7A:

0

0010.7b43.aa01

573

RCV Interface MAC address

0xC2:

0

0180.c200.0000

0

RCV IEEE spanning tree

0xC2:

1

0180.c200.0000

0

RCV IBM spanning tree

Table 19 describes the software MAC address filter information for the cable access router interface.

Table 19

show interfaces cable-modemRouting and Bridging Descriptions

 

 

Field

Description

 

 

Hash

Hash key/relative position in the keyed list for this MAC address filter.

 

 

Len

Length of this entry to the beginning element of this hash chain.

 

 

Address

Canonical (Ethernet ordered) MAC address of this filter.

 

 

Matches

Number of received packets that match this MAC address.

 

 

116 Cisco IOS Release 12.0(7)T

 

 

 

show interfaces cable-modem

 

Table 19

show interfaces cable-modemRouting and Bridging Descriptions (continued)

 

 

 

 

 

 

Field

Description

 

 

 

 

 

 

 

Act

Action to be taken when this address is looked up; choices are to receive or discard

 

 

the packet.

 

 

 

 

 

 

 

 

Type

MAC address type.

 

 

 

 

 

 

 

Related Commands

 

 

 

 

 

 

 

 

Command

 

Description

 

 

 

 

cable-modem compliant bridge

Enables DOCSIS-complianttransparent bridging on the

 

 

 

Cisco uBR900 series at startup.

 

 

 

cable-modem downstream saved channel Modifies the saved downstream channel setting and

 

 

 

upstream power value on the cable interface of a

 

 

 

Cisco uBR900 series.

 

 

 

 

cable-modem fast-search

Enables a faster downstream search algorithm on the cable

 

 

 

interface of a Cisco uBR900 series.

 

 

 

 

show bridge cable-modem

Displays bridging information for a Cisco uBR900 series

 

 

 

cable access router.

 

 

 

 

show interfaces cable-modem

Displays information about the cable interface on the

 

 

 

Cisco uBR900 series cable access router.

 

 

 

 

 

Configuring the Cisco uBR900 Series Cable Access Routers 117

Debug Commands

Debug Commands

Note Troubleshooting the Cisco uBR900 series cable access router is typically accomplished using the CMTS at the cable operator’s headend facility; it is rarely done by directly accessing the Cisco uBR924. For information on troubleshooting the Cisco uBR900 series using Cisco uBR7200 series universal broadband routers, see the documentCisco uBR7246 Universal Broadband Router Features. Also see the“Related Documents” section on page 31 for additional documents relating to troubleshooting.

The following debug commands are available to troubleshoot a Cisco uBR900 series cable access router:

debug cable-modem bpkm

debug cable-modem bridge

debug cable-modem error

debug cable-modem interrupts

debug cable-modem mac

debug cable-modem map

All commands relating to VoIP applications are documented in the Debug Command Reference for Cisco IOS Release 12.0, which can be accessed online or on the Documentation CDROM by going toCisco IOS Release 12.0 and selectingSupporting Documents.

Note Hidden debug commands for the Cisco uBR900 series cable access router are not documented.

118 Cisco IOS Release 12.0(7)T

debug cable-modembpkm

debug cable-modembpkm

To debug baseline privacy information on a Cisco uBR900 series, use the debug cable-modem bpkm command in privileged EXEC mode. To turn the debugging messages off, use theno form of this command.

[no] debugcable-modembpkm{errors| events| packets}

Syntax Description

errors

Debugs Cisco uBR900 series privacy errors.

events

Debugs events related to cable baseline privacy.

packets

Debugs baseline privacy packets.

Defaults

No default behavior or values.

Command Modes

Privileged EXEC

Command History

Release

Modification

11.3 NA

This command was introduced.

 

 

Usage Guidelines

Baseline privacy key management exchanges take place only when both the Cisco uBR900 series and the CMTS are running code images that support baseline privacy, and the privacy class of service is enabled via the configuration file that is downloaded to the cable access router. Baseline privacy code images for the Cisco uBR900 series contain k1 in the code image name.

Examples

The following example shows debug output when the headend does not have privacy enabled:

uBR924# debugcable-modembpkm errors

cm_bpkm_fsm(): machine: KEK, event/state: EVENT_4_TIMEOUT/STATE_B_AUTH_WAIT, new state: STATE_B_AUTH_WAIT

cm_bpkm_fsm(): machine: KEK, event/state: EVENT_4_TIMEOUT/STATE_B_AUTH_WAIT, new state: STATE_B_AUTH_WAIT

%LINEPROTO-5-UPDOWN:Line protocol on Interfacecable-modem0,changed state to down cm_bpkm_fsm(): machine: KEK, event/state: EVENT_1_PROVISIONED/STATE_A_START, new state: STATE_B_AUTH_WAIT

%LINEPROTO-5-UPDOWN:Line protocol on Interfacecable-modem0,changed state to up

Configuring the Cisco uBR900 Series Cable Access Routers 119

debug cable-modembpkm

Related Commands

Command

Description

 

 

debug cable-modem bridge

Debugs bridge filter processing information on a Cisco uBR900

 

series cable access router.

 

 

debug cable-modem error

Enables debugging messages for the cable interface driver on a

 

Cisco uBR900 series.

 

 

debug cable-modem interrupts

Debugs Cisco uBR900 series interrupts.

 

 

debug cable-modem mac

Troubleshoots the Cisco uBR900 series MAC layer.

 

 

debug cable-modem map

Displays the timing from MAP messages to sync messages and

 

the timing between MAP messages.

 

 

120 Cisco IOS Release 12.0(7)T

debug cable-modembridge

debug cable-modembridge

Use the debug cable-modem bridge command in privileged EXEC mode to debug bridge filter processing information on a Cisco uBR900 series. To turn the debugging messages off, use theno form of this command.

[no] debugcable-modembridge

Syntax Description

This command has no keywords or arguments.

Defaults

No default behavior or values.

Command Modes

Privileged EXEC

Command History

Release

Modification

11.3 NA

This command was introduced.

 

 

Usage Guidelines

When the interface is down, all bridge table entries learned on the Ethernet interface are set to discard because traffic is not bridged until the cable interface has completed initialization. After the interface (the line protocol) is completely up, bridge table entries learned on the Ethernet interface program the cable MAC data filters. The cable MAC hardware filters out any received packets whose addresses are not in the filters. In this way, the cable interface only receives packets addressed to its own MAC address or an address it has learned on the Ethernet interface.

Examples

The following example shows sample display output for the debug cable-modem bridge privileged EXEC command:

uBR924# debugcable-modembridge

%LINEPROTO-5-UPDOWN:Line protocol on Interfacecable-modem0,changed state to downshut cm_tbridge_add_entry(): MAC not initialized, discarding entry: 00e0.fe7a.186fno shut cm_tbridge_add_entry(): MAC not initialized, discarding entry: 00e0.fe7a.186f%LINEPROTO-5-UPDOWN:Line protocol on Interfacecable-modem0,changed state to up cm_tbridge_add_entry(): Adding entry 00e0.fe7a.186f to filter 2

Configuring the Cisco uBR900 Series Cable Access Routers 121

debug cable-modembridge

Related Commands

Command

Description

 

 

debug cable-modem bpkm

Debugs baseline privacy information on a Cisco uBR900 series.

 

 

debug cable-modem error

Enables debugging messages for the cable interface driver on a

 

Cisco uBR900 series.

 

 

debug cable-modem interrupts

Debugs Cisco uBR900 series interrupts.

 

 

debug cable-modem mac

Troubleshoots the Cisco uBR900 series MAC layer.

 

 

debug cable-modem map

Displays the timing from MAP messages to sync messages and

 

the timing between MAP messages.

 

 

122 Cisco IOS Release 12.0(7)T

debug cable-modemerror

debug cable-modemerror

Use the the debug cable-modem error command in privileged EXEC mode to enable debugging messages for the cable interface driver. To turn the debugging messages off, use theno form of this command.

[no] debugcable-modemerror

Syntax Description

This command has no keywords or arguments.

Defaults

No default behavior or values.

Command Modes

Privileged EXEC

Command History

Release

Modification

11.3 NA

This command was introduced.

 

 

Usage Guidelines

This command displays detailed output about the sanity checking of received frame formats, the acquisition of downstream QAM/FEC lock, the receipt or non-receiptof SYNC messages from the CMTS, reception errors, and bandwidth request failures.

Examples

The following example shows sample display output for the debug cable-modem error privileged EXEC command:

uBR924#

debug cable-modemerror

 

*Mar

7

20:16:29: AcquireSync(): Update rate is 100 Hz

*Mar

7

20:16:30: 1st Sync

acquired after

1100 ms.

*Mar

7

20:16:30: Recovery

loop is locked

(7/9)

*Mar

7

20:16:30: 2nd Sync

acquired after

100 ms.

*Mar

7

20:16:30: Recovery

loop is locked

(10/15)

Configuring the Cisco uBR900 Series Cable Access Routers 123

debug cable-modemerror

Related Commands

Command

Description

 

 

debug cable-modem bpkm

Debugs baseline privacy information on a Cisco uBR900 series.

 

 

debug cable-modem bridge

Debugs bridge filter processing information on a Cisco uBR900

 

series.

 

 

debug cable-modem interrupts

Debugs Cisco uBR900 series interrupts.

 

 

debug cable-modem mac

Troubleshoots the Cisco uBR900 series MAC layer.

 

 

debug cable-modem map

Displays the timing from MAP messages to sync messages and

 

the timing between MAP messages.

 

 

124 Cisco IOS Release 12.0(7)T

debug cable-modeminterrupts

debug cable-modeminterrupts

To debug Cisco uBR900 series interrupts, use the debug cable-modem interrupts command in privileged EXEC mode . To turn the debugging messages off, use theno form of this command.

[no] debugcable-modeminterrupts

Syntax Description

This command has no keywords or arguments.

Defaults

No default behavior or values.

Command Modes

Privileged EXEC

Command History

Release

Modification

11.3 NA

This command was introduced.

 

 

Examples

The following example shows sample debug output for Cisco uBR900 series interrupts.

uBR924# debugcable-modeminterrupts

***BCM3300_rx_mac_msg_interrupt ***

***BCM3300_rx_mac_msg_interrupt ***

### BCM3300_tx_interrupt ###

***BCM3300_rx_mac_msg_interrupt ***

### BCM3300_tx_interrupt ###

***BCM3300_rx_mac_msg_interrupt ***

### BCM3300_tx_interrupt ###

### BCM3300_tx_interrupt ###

### BCM3300_tx_interrupt ###

### BCM3300_tx_interrupt ###

Configuring the Cisco uBR900 Series Cable Access Routers 125

debug cable-modeminterrupts

Related Commands

Command

Description

 

 

debug cable-modem bpkm

Debugs baseline privacy information on a Cisco uBR900 series.

 

 

debug cable-modem bridge

Debugs bridge filter processing information on a Cisco uBR900

 

series.

 

 

debug cable-modem error

Enables debugging messages for the cable interface driver on a

 

Cisco uBR900 series.

 

 

debug cable-modem mac

Troubleshoots the Cisco uBR900 series MAC layer.

 

 

debug cable-modem map

Displays the timing from MAP messages to sync messages and

 

the timing between MAP messages.

 

 

126 Cisco IOS Release 12.0(7)T

debug cable-modemmac

debug cable-modemmac

To troubleshoot the Cisco uBR900 series MAC layer, use the debug cable-modem mac command in privileged EXEC mode. To turn the debugging messages off, use theno form of this command.

[no] debugcable-modemmac{log[verbose] | messages}

Syntax Description

log

Realtime MAC log display.

verbose

(Optional) Displays periodic MAC layer events, such as ranging.

messages

MAC layer management messages.

Defaults

No default behavior or values.

Command Modes

Privileged EXEC

Command History

Release

Modification

11.3 NA

This command was introduced.

 

 

Usage Guidelines

Of all the available debug cable modem commands, the most useful is debug cable-modem mac log.

MAC log messages are written to a circular log file even when debugging is not turned on. These messages include timestamps, events, and information pertinent to these events. Enter the debug cable-modem mac log command to view MAC log messages. If you want to view this information without entering debug mode, enter theshow controllers cable-modem number mac log command. The same information is displayed by both commands.

If the Cisco uBR900 series interface fails to come up or resets periodically, the MAC log will show what happened. For example, if an address is not obtained from the DHCP server, an error is logged, initialization starts over, and the Cisco uBR900 series scans for a downstream frequency. The debug cable-modem mac log command displays the log from the oldest to the newest entry.

After initial ranging is successful (dhcp_state has been reached), further RNG-REQ/RNG-RSP messages and watchdog timer entries are suppressed from output unless theverbose keyword is used. Note thatCMAC_LOG_WATCHDOG_TIMER entries while in the maintenance_state are normal when using theverbose keyword.

Configuring the Cisco uBR900 Series Cable Access Routers 127

debug cable-modemmac

Examples

Example 1

This example shows sample display output from the debug cable-modem mac log command. The fields of the output are the time since bootup, the log message, and in some cases a parameter that gives more detail about the log entry.

uBR924#

debug cable-modemmac log

 

*Mar

7

01:42:59: 528302.040 CMAC_LOG_LINK_DOWN

 

*Mar

7

01:42:59: 528302.042 CMAC_LOG_RESET_FROM_DRIVER

 

*Mar

7

01:42:59: 528302.044 CMAC_LOG_STATE_CHANGE

wait_for_link_up_state

*Mar

7

01:42:59: 528302.046 CMAC_LOG_DRIVER_INIT_IDB_SHUTDOWN

0x08098D02

*Mar

7

01:42:59: 528302.048 CMAC_LOG_LINK_DOWN

 

*Mar

7

01:43:05: 528308.428 CMAC_LOG_DRIVER_INIT_IDB_RESET

0x08098E5E

*Mar

7

01:43:05: 528308.432 CMAC_LOG_LINK_DOWN

 

*Mar

7

01:43:05: 528308.434 CMAC_LOG_LINK_UP

 

*Mar

7

01:43:05: 528308.436 CMAC_LOG_STATE_CHANGE

ds_channel_scanning_state

*Mar

7

01:43:05: 528308.440 CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

88/453000000/855000000/6000000

*Mar

7

01:43:05: 528308.444 CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

89/93000000/105000000/6000000

*Mar

7

01:43:05: 528308.448 CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

90/111250000/117250000/6000000

*Mar

7

01:43:05: 528308.452 CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

91/231012500/327012500/6000000

*Mar

7

01:43:05: 528308.456 CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

92/333015000/333015000/6000000

*Mar

7

01:43:05: 528308.460 CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

93/339012500/399012500/6000000

*Mar

7

01:43:05: 528308.462 CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

94/405000000/447000000/6000000

*Mar

7

01:43:05: 528308.466 CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

95/123015000/129015000/6000000

*Mar

7

01:43:05: 528308.470 CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

96/135012500/135012500/6000000

*Mar

7

01:43:05: 528308.474 CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

97/141000000/171000000/6000000

*Mar

7

01:43:05: 528308.478 CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

98/219000000/225000000/6000000

*Mar

7

01:43:05: 528308.482 CMAC_LOG_WILL_SEARCH_DS_FREQUENCY_BAND

99/177000000/213000000/6000000

*Mar

7

01:43:05: 528308.486 CMAC_LOG_WILL_SEARCH_SAVED_DS_FREQUENCY

663000000

*Mar

7

01:43:05: 528308.488 CMAC_LOG_WILL_SEARCH_USER_DS_FREQUENCY

663000000

*Mar

7

01:43:07: 528310.292 CMAC_LOG_DS_64QAM_LOCK_ACQUIRED

663000000

.

 

 

528383.992

CMAC_LOG_STATE_CHANGE

registration_state

528384.044

CMAC_LOG_REG_REQ_MSG_QUEUED

 

528384.050

CMAC_LOG_REG_REQ_TRANSMITTED

 

528384.052

CMAC_LOG_REG_RSP_MSG_RCVD

 

528384.078

CMAC_LOG_COS_ASSIGNED_SID

1/4

528384.102

CMAC_LOG_RNG_REQ_QUEUED

4

528384.102

CMAC_LOG_REGISTRATION_OK

 

528384.102

CMAC_LOG_STATE_CHANGE

establish_privacy_state

528384.102

CMAC_LOG_STATE_CHANGE

maintenance_state

528388.444

CMAC_LOG_RNG_REQ_TRANSMITTED

 

528388.444

CMAC_LOG_RNG_RSP_MSG_RCVD

 

528398.514

CMAC_LOG_RNG_REQ_TRANSMITTED

 

528398.516

CMAC_LOG_RNG_RSP_MSG_RCVD

 

528408.584

CMAC_LOG_RNG_REQ_TRANSMITTED

 

528408.586

CMAC_LOG_RNG_RSP_MSG_RCVD

 

528414.102

CMAC_LOG_WATCHDOG_TIMER

 

528418.654

CMAC_LOG_RNG_REQ_TRANSMITTED

 

528418.656

CMAC_LOG_RNG_RSP_MSG_RCVD

 

528428.726

CMAC_LOG_RNG_REQ_TRANSMITTED

 

528428.728

CMAC_LOG_RNG_RSP_MSG_RCVD

 

528438.796

CMAC_LOG_RNG_REQ_TRANSMITTED

 

528438.798

CMAC_LOG_RNG_RSP_MSG_RCVD

 

528444.102

CMAC_LOG_WATCHDOG_TIMER

 

528444.492

CMAC_LOG_LINK_DOWN

 

528444.494

CMAC_LOG_RESET_FROM_DRIVER

 

528444.494

CMAC_LOG_STATE_CHANGE

wait_for_link_up_state

528444.494

CMAC_LOG_DRIVER_INIT_IDB_SHUTDOWN

0x08098D02

528444.494

CMAC_LOG_LINK_DOWN

 

528474.494

CMAC_LOG_WATCHDOG_TIMER

 

528504.494

CMAC_LOG_WATCHDOG_TIMER

 

528534.494

CMAC_LOG_WATCHDOG_TIMER

 

128 Cisco IOS Release 12.0(7)T

debug cable-modemmac

0 events dropped due to lack of a chunk

The line “0 events dropped due to lack of a chunk” at the end of a display indicates that no log entries were discarded due to a temporary lack of memory. This means the log is accurate and reliable.

Example 2

The following example compares the output of the debug cable-modem mac log command with thedebug cable-modem mac log verbose command. Theverbose keyword displays periodic events such as ranging.

uBR924# debug cable mac log

Cable Modem mac log debugging is on uBR924#

uBR924# debug cable mac log verbose

Cable Modem mac log debugging is on (verbose) uBR924#

574623.810

CMAC_LOG_RNG_REQ_TRANSMITTED

574623.812

CMAC_LOG_RNG_RSP_MSG_RCVD

574627.942

CMAC_LOG_WATCHDOG_TIMER

574633.880

CMAC_LOG_RNG_REQ_TRANSMITTED

574633.884

CMAC_LOG_RNG_RSP_MSG_RCVD

574643.950

CMAC_LOG_RNG_REQ_TRANSMITTED

574643.954

CMAC_LOG_RNG_RSP_MSG_RCVD

574654.022

CMAC_LOG_RNG_REQ_TRANSMITTED

574654.024

CMAC_LOG_RNG_RSP_MSG_RCVD

574657.978

CMAC_LOG_WATCHDOG_TIMER

574664.094

CMAC_LOG_RNG_REQ_TRANSMITTED

574664.096

CMAC_LOG_RNG_RSP_MSG_RCVD

574674.164

CMAC_LOG_RNG_REQ_TRANSMITTED

574674.166

CMAC_LOG_RNG_RSP_MSG_RCVD

uBR924# no

debug cable mac log verbose

Cable Modem mac log debugging is off

uBR924#

 

574684.234

CMAC_LOG_RNG_REQ_TRANSMITTED

574684.238

CMAC_LOG_RNG_RSP_MSG_RCVD

Example 3

The following example shows display output for the debug cable mac messages command. This command causes received cable MAC management messages to be displayed in a verbose format. The messages that are displayed are shown below:

uBR924# debugcable-modemmac messages ?

dynsrv

dynamic service mac messages

map

map messages received

reg-req

reg-req

messages transmitted

reg-rsp

reg-rspmessages received

rng-req

rng-req

messages transmitted

rng-rsp

rng-rspmessages received

sync

Sync messages received

ucc-req

ucc-reqmessages received

ucc-rsp

ucc-rspmessages transmitted

ucd

UCD messages received

<cr>

 

 

The dynsrv keyword displays Dynamic Service Add or Dynamic Service Delete messages during theoff-hook/on-hooktransitions of a phone connected to the Cisco uBR900 series.

Configuring the Cisco uBR900 Series Cable Access Routers 129

debug cable-modemmac

In addition, transmitted REG-REQsare displayed in hex dump format. The output from this command is very verbose and is usually not needed for normal interface debugging. The command is most useful when attempting to attach a Cisco uBR900 series cable access router to a CMTS that is notDOCSIS-qualified.

For a description of the displayed fields of each message, refer to the DOCSIS Radio Frequency Interface Specification, v1.0 (SP-RFI-I04-980724).

uBR924#

debug cable mac messages

 

 

 

*Mar

7

01:44:06:

 

 

 

 

*Mar

7

01:44:06: UCD MESSAGE

 

 

 

*Mar

7

01:44:06: -----------

 

 

 

*Mar

7

01:44:06:

FRAME HEADER

 

 

 

*Mar

7

01:44:06:

FC

-

0xC2 == MAC Management

*Mar

7

01:44:06:

MAC_PARM

-

0x00

*Mar

7

01:44:06:

LEN

-

0xD3

*Mar

7

01:44:06:

MAC MANAGEMENT MESSAGE HEADER

 

 

*Mar

7

01:44:06:

DA

-

01E0.2F00.0001

*Mar

7

01:44:06:

SA

-

00E0.1EA5.BB60

*Mar

7

01:44:06:

msg LEN

-

C1

 

*Mar

7

01:44:06:

DSAP

-

0

 

*Mar

7

01:44:06:

SSAP

-

0

 

*Mar

7

01:44:06:

control

-

03

 

*Mar

7

01:44:06:

version

-

01

 

*Mar

7

01:44:06:

type

-

02 == UCD

*Mar

7

01:44:06:

RSVD

-

0

 

*Mar

7

01:44:06:

US Channel ID

-

1

 

*Mar

7

01:44:06:

Configuration Change Count

-

4

 

*Mar

7

01:44:06:

Mini-SlotSize

-

8

 

*Mar

7

01:44:06:

DS Channel ID

-

1

 

*Mar

7

01:44:06:

Symbol Rate

-

8

 

*Mar

7

01:44:06:

Frequency

-

20000000

*Mar

7

01:44:06:

Preamble Pattern

-

CC CC CC CC CC CC CC CC CC CC CC CC CC CC 0D 0D

*Mar

7

01:44:06:

Burst Descriptor 0

 

 

 

*Mar

7

01:44:06:

Interval Usage Code

-

1

 

*Mar

7

01:44:06:

Modulation Type

-

1

== QPSK

*Mar

7

01:44:06:

Differential Encoding

-

2

== OFF

*Mar

7

01:44:06:

Preamble Length

-

64

 

*Mar

7

01:44:06:

Preamble Value Offset

-

56

 

*Mar

7

01:44:06:

FEC Error Correction

-

0

 

*Mar

7

01:44:06:

FEC Codeword Info Bytes

-

16

 

*Mar

7

01:44:06:

Scrambler Seed

-

0x0152

*Mar

7

01:44:06:

Maximum Burst Size

-

1

 

*Mar

7

01:44:06:

Guard Time Size

-

8

 

*Mar

7

01:44:06:

Last Codeword Length

-

1

== FIXED

*Mar

7

01:44:06:

Scrambler on/off

-

1

== ON

*Mar

7

01:44:06:

Burst Descriptor 1

 

 

 

*Mar

7

01:44:06:

Interval Usage Code

-

3

 

*Mar

7

01:44:06:

Modulation Type

-

1

== QPSK

*Mar

7

01:44:06:

Differential Encoding

-

2

== OFF

*Mar

7

01:44:06:

Preamble Length

-

128

*Mar

7

01:44:06:

Preamble Value Offset

-

0

 

*Mar

7

01:44:06:

FEC Error Correction

-

5

 

*Mar

7

01:44:06:

FEC Codeword Info Bytes

-

34

 

*Mar

7

01:44:06:

Scrambler Seed

-

0x0152

*Mar

7

01:44:06:

Maximum Burst Size

-

0

 

*Mar

7

01:44:06:

Guard Time Size

-

48

 

*Mar

7

01:44:06:

Last Codeword Length

-

1

== FIXED

*Mar

7

01:44:06:

Scrambler on/off

-

1

== ON

*Mar

7

01:44:06:

Burst Descriptor 2

 

 

 

*Mar

7

01:44:06:

Interval Usage Code

-

4

 

*Mar

7

01:44:06:

Modulation Type

-

1

== QPSK

*Mar

7

01:44:06:

Differential Encoding

-

2

== OFF

*Mar

7

01:44:06:

Preamble Length

-

128

130 Cisco IOS Release 12.0(7)T

debug cable-modemmac

*Mar

7

01:44:06:

Preamble Value Offset

-

0

 

*Mar

7

01:44:06:

FEC Error Correction

-

5

 

*Mar

7

01:44:06:

FEC Codeword Info Bytes

-

34

 

*Mar

7

01:44:06:

Scrambler Seed

 

-

0x0152

*Mar

7

01:44:06:

Maximum Burst Size

-

0

 

*Mar

7

01:44:06:

Guard Time Size

 

-

48

 

*Mar

7

01:44:06:

Last Codeword Length

-

1 ==

FIXED

*Mar

7

01:44:06:

Scrambler on/off

-

1 ==

ON

*Mar

7

01:44:06:

Burst Descriptor 3

 

 

 

*Mar

7

01:44:06:

Interval Usage Code

-

5

 

*Mar

7

01:44:06:

Modulation Type

 

-

1 ==

QPSK

*Mar

7

01:44:06:

Differential Encoding

-

2 ==

OFF

*Mar

7

01:44:06:

Preamble Length

 

-

72

 

*Mar

7

01:44:06:

Preamble Value Offset

-

48

 

*Mar

7

01:44:06:

FEC Error Correction

-

5

 

*Mar

7

01:44:06:

FEC Codeword Info Bytes

-

75

 

*Mar

7

01:44:06:

Scrambler Seed

 

-

0x0152

*Mar

7

01:44:06:

Maximum Burst Size

-

0

 

*Mar

7

01:44:06:

Guard Time Size

 

-

8

 

*Mar

7

01:44:06:

Last Codeword Length

-

1 ==

FIXED

*Mar

7

01:44:06:

Scrambler on/off

-

1 ==

ON

*Mar

7

01:44:06:

 

 

 

 

 

 

*Mar

7

01:44:06:

 

 

 

 

 

 

*Mar

7

01:44:06: MAP MESSAGE

 

 

 

 

*Mar

7

01:44:06: -----------

 

 

 

 

*Mar

7

01:44:06:

FRAME HEADER

 

 

 

 

*Mar

7

01:44:06:

FC

 

 

-

0xC3

== MAC Management with Extended Header

*Mar

7

01:44:06:

MAC_PARM

 

-

0x02

 

*Mar

7

01:44:06:

LEN

 

 

-

0x42

 

*Mar

7

01:44:06:

EHDR

 

 

-

0x00

0x00

*Mar

7

01:44:06:

MAC MANAGEMENT MESSAGE HEADER

 

 

*Mar

7

01:44:06:

DA

 

 

-

01E0.2F00.0001

.

 

 

 

 

 

 

 

 

*Mar

7

01:44:17: RNG-RSPMESSAGE

 

 

 

 

*Mar

7

01:44:17: ---------------

 

 

 

 

*Mar

7

01:44:17:

FRAME HEADER

 

 

 

 

*Mar

7

01:44:17:

FC

 

 

-

0xC2

== MAC Management

*Mar

7

01:44:17:

MAC_PARM

 

-

0x00

 

*Mar

7

01:44:17:

LEN

 

 

-

0x2B

 

*Mar

7

01:44:17:

MAC MANAGEMENT MESSAGE HEADER

 

 

*Mar

7

01:44:17:

DA

 

 

-

00F0.1EB2.BB61

.

 

 

 

 

 

 

 

 

*Mar

7

01:44:20: REG-REQMESSAGE

 

 

 

 

*Mar

7

01:44:20: ---------------

 

 

 

 

*Mar

7

01:44:20: C20000A5 000000E0

1EA5BB60 00F01EB2

 

*Mar

7

01:44:20: BB610093

00000301

06000004

03010104

 

*Mar

7

01:44:20:

1F010101

0204003D

09000304

001E8480

 

*Mar

7

01:44:20:

04010705

04000186

A0060200

0C070101

 

*Mar

7

01:44:20:

080300F0

1E112A01

04000000

0A020400

 

*Mar

7

01:44:20:

00000A03

04000002

58040400

00000105

 

*Mar

7

01:44:20:

04000000

01060400

00025807

04000000

 

*Mar

7

01:44:20: 3C2B0563

6973636F

06105E4F

C908C655

 

*Mar

7

01:44:20: 61086FD5

5C9D756F

7B730710

434D5453

 

*Mar

7

01:44:20: 204D4943 202D2D2D

2D2D2D2D 0C040000

 

*Mar

7

01:44:20: 00000503 010100

 

 

 

 

*Mar

7

01:44:20:

 

 

 

 

 

 

*Mar

7

01:44:20:

 

 

 

 

 

 

*Mar

7

01:44:20: REG-RSPMESSAGE

 

 

 

 

*Mar

7

01:44:20: ---------------

 

 

 

 

*Mar

7

01:44:20:

FRAME HEADER

 

 

 

 

*Mar

7

01:44:20:

FC

 

 

-

0xC2

== MAC Management

*Mar

7

01:44:20:

MAC_PARM

 

-

0x00

 

*Mar

7

01:44:20:

LEN

 

 

-

0x29

 

*Mar

7

01:44:20:

MAC MANAGEMENT MESSAGE HEADER

 

 

*Mar

7

01:44:20:

DA

 

 

-

00F0.1EB2.BB61

Configuring the Cisco uBR900 Series Cable Access Routers 131

debug cable-modemmac

Related Commands

Command

Description

 

 

debug cable-modem bpkm

Debugs baseline privacy information on a Cisco uBR900 series.

 

 

debug cable-modem bridge

Debugs bridge filter processing information on a Cisco uBR900

 

series.

 

 

debug cable-modem error

Enables debugging messages for the cable interface driver on a

 

Cisco uBR900 series.

 

 

debug cable-modem interrupts

Debugs Cisco uBR900 series interrupts.

 

 

debug cable-modem map

Displays the timing from MAP messages to sync messages and

 

the timing between MAP messages.

 

 

132 Cisco IOS Release 12.0(7)T

debug cable-modemmap

debug cable-modemmap

To display the timing from MAP messages to sync messages and the timing between MAP messages on a Cisco uBR900 series cable access router, use the debug cable-modem map command in privileged EXEC mode. To turn the debugging messages off, use theno form of this command.

[no] debugcable-modemmap

Syntax Description

This command has no keywords or arguments.

Defaults

No default behavior or values.

Command Modes

Privileged EXEC

Command History

Release

Modification

11.3 NA

This command was introduced.

 

 

Examples

The following example shows display output for the debug cable-modem map privileged EXEC command.

uBR924#

debug cable-modemmap

Cable

Modem MAP debugging is on

uBR924#

 

*Mar

7

20:12:08: 595322.942: Min MAP to sync=72

*Mar

7

20:12:08: 595322.944: Max map to map time is 40

*Mar

7

20:12:08: 595322.982: Min MAP to sync=63

*Mar

7

20:12:08: 595323.110: Max map to map time is 41

*Mar

7

20:12:08: 595323.262: Min MAP to sync=59

*Mar

7

20:12:08: 595323.440: Max map to map time is 46

*Mar

7

20:12:09: 595323.872: Min MAP to sync=58

Configuring the Cisco uBR900 Series Cable Access Routers 133

debug cable-modemmap

Related Commands

Command

Description

 

 

debug cable-modem bpkm

Debugs baseline privacy information on a Cisco uBR900 series.

 

 

debug cable-modem bridge

Debugs bridge filter processing information on a Cisco uBR900

 

series.

 

 

debug cable-modem error

Enables debugging messages for the cable interface driver on a

 

Cisco uBR900 series.

 

 

debug cable-modem interrupts

Debugs Cisco uBR900 series interrupts.

 

 

debug cable-modem mac

Troubleshoots the Cisco uBR900 series MAC layer.

 

 

134 Cisco IOS Release 12.0(7)T

Glossary

Glossary

broadband—Transmissionsystem that combines multiple independent signals onto one cable. In the cable industry, broadband refers to thefrequency-divisionmultiplexing of many signals in a wide bandwidth of RF frequencies using a hybridfiber-coaxial(HFC) network.

CATV—Originallystood for Community Antenna Television. Now refers to any coaxial or fibercable-basedsystem that provides television services.

cable modem (CM)—Amodulator-demodulatordevice that is placed at subscriber locations to convey data communications on a cable television system. The Cisco uBR900 series cable access router is also a cable modem.

Cable Modem Termination System (CMTS)—Atermination system located at the cable television system headend or distribution hub which provides complementary functionality to the cable modems, enabling data connectivity to awide-arenetwork.

cable router—Amodularchassis-basedrouter optimized fordata-over-CATVhybridfiber-coaxial(HFC) applications.

carrier—Asignal on which another,lower-frequencysignal is modulated in order to transport thelower-frequencysignal to another location.

Carrier-to-Noise—C/N(also CNR). The difference in amplitude between the desired RF carrier and the noise in a portion of the spectrum.

channel—Aspecific frequency allocation and bandwidth. Downstream channels used for television are 6 MHz wide in the United States; 8 MHz wide in Europe.

CM—cablemodem.

CMTS—CableModem Termination System.

coaxial cable—Theprincipal physical media over which CATV systems are built.

CPE—CustomerPremises Equipment

dB—Decibel.A measure of the relative strength of two signals.

dBm—Decibelswith respect to one milliwatt. A unit of RF signal strength used in satellite work and other communications applications.

dBmV—Decibelswith respect to one millivolt in a75-ohmsystem. The unit of RF power used in CATV work in North America.

DHCP—DynamicHost Configuration Protocol. This protocol provides a mechanism for allocating IP addresses dynamically so that addresses can be reused when hosts no longer need them.

DOCSIS—DataOver Cable Service Interface Specification. Defines technical specifications for equipment at both subscriber locations and cable operators’ headends.

downstream—Theset of frequencies used to send data from a headend to a subscriber.

FDM—FrequencyDivision Multiplexing. A data transmission method in which a number of transmitters share a transmission medium, each occupying a different frequency.

FEC—ForwardError Correction. In data transmission, a process by which additional data is added that is derived from the payload by an assigned algorithm. It allows the receiver to determine if certain classes of errors have occurred in transmission and, in some cases, allows other classes of errors to be corrected.

Configuring the Cisco uBR900 Series Cable Access Routers 135

Glossary

headend—Centraldistribution point for a CATV system. Video signals are received here from satellite (eitherco-locatedor remote), frequency converted to the appropriate channels, combined with locally originated signals, and rebroadcast onto the HFC plant. For a CATV data system, the headend is the typical place to create a link between the HFC system and any external data networks.

HFC—Hybridfiber-coaxial(cable network). Older CATV systems were provisioned using only coaxial cable. Modern systems use fiber transport from the headend to an optical node located in the neighborhood to reduce system noise. Coaxial cable runs from the node to the subscriber. The fiber plant is generally a star configuration with all optical node fibers terminating at a headend. The coaxial cable part of the system is generally atrunk-and-branchconfiguration.

host—Anyend-usercomputer system that connects to a network. In this document, the term host refers to the computer system connected to the LAN interface of the cable access router.

ingress noise—Over-the-airsignals that are inadvertently coupled into the nominally closed coaxial cable distribution system. Ingress noise is difficult to track down and intermittent in nature.

MAC layer—MediaAccess Control sublayer. Controls access by the cable access router to the CMTS and to the upstream data slots.

MCNS—MultimediaCable Network System Partners Ltd. A consortium of cable companies providing service to the majority of homes in the United States and Canada. This consortium has decided to drive a standard with the goal of having interoperable cable access routers.

MSO—MultipleSystem Operator. A cable service provider that operates in more than one geographic area, thus having multiple headend facilities.

narrowband—Asingle RF frequency.

NTSC—NationalTelevision Systems Committee. A United States TV technical standard, named after the organization that created the standard in 1941. Specifies a 6MHz-widemodulated signal.

PAL—PhaseAlternating Line. The TV system used in most of Europe, in which the color carrier phase definition changes in alternate scan lines. Utilizes an 8MHz-widemodulated signal.

QAM—QuadratureAmplitude Modulation. A method of modulating digital signals onto aradio-frequencycarrier signal in which the value of a symbol consisting of multiple bits is represented by amplitude and phase states of the carrier. QAM is a modulation scheme mostly used in the downstream direction(64-QAM,256-QAM).16-QAMis expected to be usable in the upstream direction. Numbers indicate number of code points per symbol. The QAM rate or the number of points in the QAM constellation can be computed by 2 raised to the power of <number of bits/symbol>. For example,16-QAMhas 4 bits per symbol,64-QAMhas 6 bits per symbol, and256-QAMhas 8 bits per symbol.

QPSK—QuadraturePhase-ShiftKeying. A digital modulation method in which there are 2 data bits represented with each baud symbol.

ranging—Theprocess of acquiring the correct timing offset such that the transmissions of a cable access router are aligned with the correctmini-slotboundary.

RF—Radiofrequency. The portion of the electromagnetic frequency spectrum from 5 MHz to approximately 860 MHz.

SECAM—TVsystem used in France and elsewhere, utilizing an 8MHz-widemodulated signal.

SID (Service ID)—Anumber that defines (at the MAC sublayer) a particular mapping between a cable access router (CM) and the CMTS. The SID is used for the purpose of upstream bandwidth allocation andclass-of-servicemanagement.

Signal-to-Noise—S/N(also SNR). The difference in amplitude between a baseband signal and the noise in a portion of the spectrum.

136 Cisco IOS Release 12.0(7)T

Glossary

spectrum reuse—CATV’smost fundamental concept. Historically, theover-the-airspectrum has been assigned to many purposes other than that of carrying TV signals. This has resulted in an inadequate supply of spectrum to serve the needs of viewers. Cable can reuse spectrum that is sealed in its aluminum tubes.

subscriber unit (SU)—Analternate term for cable access router. Seecable access router.

upstream—Theset of frequencies used to send data from a subscriber to the headend.

Configuring the Cisco uBR900 Series Cable Access Routers 137

Glossary

138 Cisco IOS Release 12.0(7)T