Cisco Systems BC-281 User Manual

Configuring Data-Link Switching Plus

This chapter describes how to configure data-link switching plus (DLSw+), Cisco’s implementation of the DLSw standard for Systems Network Architecture (SNA) and NetBIOS de vices. Refer to the DLSw+ Design and Implementation Guide for more complex configuration instructions. For a complete description of the DLSw+ commands mentioned in this chapter, refer to the “DLSw+ Commands” chapter of the Cisco IOS Bridging and IBM Networking Command Reference (Volume 1 of 2). To locate documentation of other commands that appear in this chapter, use the command reference master index or search online.

This chapter contains the following sections:

• Technology Overview, page 281

• DLSw+ Configuration Task List, page 288

• Verifying DLSw+, page 310

• Monitoring and Maintaining the DLSw+ Network, page 311

• DLSw+ Configuration Examples, page 312

To identify the hardware platform or software image information associated with a feature, use the Feature Navigator on Cisco.com to search for information about the feature or refer to the software release notes for a specific release. For more information, see the “Identifying Platform Support for Cisco IOS Software Features” section on page lv in the “Using Cisco IOS Software” chapter.

Technology Overview

DLSw+ is a method of transporting SNA and Net BIOS. It complies with the DLSw standard documented in RFC 1795 and the DLSw Version 2 standard. DLSw+ is an alternative to RSRB that addresses several inherent problems that exist in RSRB, such as:

• SRB hop-count limits (SRB’s limit is seven)

• Broadcast traffic (including SRB explorer frames or NetBIOS name queries)

• Unnecessary traffic (acknowledgments and keepalives)

• Data-link control timeouts

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Technology Overview

DLSw Standard

The DLSw standard, documented in RFC 1795, defines the switch-to-switch protocol between DLSw routers. The standard also defines a mechanism to terminate data-link control connections locally and multiplex the traffic from the data-link control connections to a TCP connection. The standard always calls for the transport protocol to be TCP and always requires that data-link control connections be locally terminated (the eq uivalent of Cisco’s local acknowledgment option). The standard also requires that the SRB RIF be terminated at the DLSw router. The standard describes a means for prioritization and flow control and defines error recovery procedures that ensure data-link control connections are appropriately disabled if any part of their associated circuits breaks.

The DLSw standard does not specify when to establish TCP connections. The capabilities exchange allows compliance to the standard, bu t at different levels of support. The standard does not specify how to cache learned information about MAC addresses, RIFs, or NetBIOS names. It also does not describe how to track either capable or preferred DLSw partners for either backup or load-balancing purposes. The standard does not provide the specifics of media conversion, but leaves the details up to the implementation. It does not define how to map switch congestion to the flow control for data-link control. Finally, the MIB is documented under a separate RFC.

Configuring Data-Link Switching Plus

DLSw Version 2 Standard

In the Version 1 standard, a network design requires fully meshed connectivity so that all peers were connect to every other peer. This design creates unnecessary broadcast traffic because an explorer propagates to every peer for every broadcast.

The Version 2 standard is documented in RFC 2166. It includes RFC 1795 and adds the following enhancements:

• IP Multicast, page 282

• UDP Unicast, page 283

• Enhanced Peer-on-Demand Routing Feature, page 283

• Expedited TCP Connection, page 283

Users implement DLSw Version 2 for scalability if they are using multivend or DLSw de vices with an IP multicast network. DLSw Version 2 requires complex planning because it involves configuration changes across an IP network.

IP Multicast

Multicast service avoids duplication and excessive bandwidth of broadcast traffic because it replicates and propagates messages to its multicast members only as necessary. It re duces the amount of network overhead in the following ways:

• A v oids the need to maintain TCP Switch-to-Switch Protocol (SSP) connections between two DLSw

peers when no circuits are available

• Ensures that each broadcast results in only a single explorer over every link

DLSw Version 2 is for customers who run a multicast IP network and do not need the advantages of border peering.

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UDP Unicast

DLSw Version 2 uses UDP unicast in response to an IP multicast. When address resolution packets (CANUREACH_EX, NETBIOS_NQ_ex, NETBIOS_ANQ, and DATAFRAME) are sent to multiple destinations (IP multicast service), DLSw Version 2 sends the response frames (ICANREACH_ex and NAME_RECOGNIZED_ex) via UDP unicast.

UDP unicast uses UDP source port 0. Howe ver , some fire wall products treat packets th at use UDP source port 0 as security violations, discarding the pa ckets and preventing DLSw connections. To avoid this situation, use one of the following procedures:

• Configure the firewall to allow UDP packets to use UDP source port 0.

• Use the dlsw udp-disable command to disable UDP unicast and send address resolution packets in

the existing TCP session.

Enhanced Peer-on-Demand Routing Feature

DLSw V ersion 2 establishes TCP connections only when necessary and the TCP connections are brought down when there are no circuits to a DLSw peer for a specified amount of time. This method, known as peer-on-demand routing, was recently introduced in DLSw Version 2, but has been implemented in Cisco DLSw+ border peer technology since Cisco IOS Release 10.3.

Technology Overview

Expedited TCP Connection

DLSw Version 2 efficiently establishes TCP connections. Prev iously, DLSw created two unidirectional TCP connections and then disconnected one after the capabilities exchange took place. With DLSw Version 2, a single bidirectional TCP connection establishes if the peer is brought up as a result of an IP multicast/UDP unicast information exchange.

DLSw+ Features

DLSw+ is Cisco’s version of DLSw and it supports several additional features and enhancements. DLSw+ is a means of transporting SNA and NetBIOS traffic over a campus or WAN. The end systems can attach to the network over T ok en Ring, Ethernet, Synchronous Data Link Control (SDLC) Protocol, Qualified Logical Link Control (QLLC), or Fiber Distributed Data Interface (FDDI). See the DLSw+ Design and Implementation Guide Appendix B, “DLSw+ Support Matrix,” for details. DLSw+ switches between diverse media and locally terminates the data links, keeping acknowl edgments, k eep ali v es, and polling off the WAN. Local termination of data links also eliminates data-link control timeouts that can occur during transient network congestion or when rerouting around failed links. Finally, DLSw+ provides a mechanism for dynamically searching a network for SNA or NetBIOS resources and includes caching algorithms that minimize broadcast traffic.

DLSw+ is fully compatible with any vendor’ s RFC 1795 implementation and the following features are available when both peers are using DLSw+:

• Peer groups and border peers

• Backup peers

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• Promiscuous and on-demand peers

• Explorer firewalls and location learning

• NetBIOS dial-on-demand routing feature support

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Configuring Data-Link Switching Plus

• UDP unicast support

• Load balancing

• Support for LLC1 circuits

• Support for multiple bridge groups

• Support for RIF Passthrough

• SNA type of service feature support

• Local acknowledgment for Ethernet-attached devices and media conversion for SNA PU 2.1 and

PU 2.0 devices

• Conversion between LLC2 to SDLC between PU 4 devices

• Local or remote media conversion between LANs and either SDLC Protocol or QLLC

• SNA View, Blue Maps, and Internetwork Status Monitor (ISM) support

MIB enhancements that allow DLSw+ features to be managed by the CiscoWorks Blue products, SNA Maps, and SNA V ie w. Also, new traps alert network management stations of peer or circuit failures. For more information, refer to the current Cisco IOS release note for the location of the Cisco MIB website.

Local Acknowledgment

When you have LANs separated by wide geographic distances, and you want to avoid sending data multiple times, and the loss of user sessions that can occur with time delays, encapsulate the source-route bridged traffic inside IP datagrams passed over a TCP connection between two routers with local acknowledgment enabled.

Logical Link Control, type 2 (LLC2) is an ISO st andard dat a-link level protocol used in Token Ring networks. LLC2 was designed to provide reliable sending of data across LAN media and to cause minimal or at least predictable time delays. However, DLSw+ and WAN backbones created LANs that are separated by wide, geographic distances-spanning countries and continents. As a result, LANs have time delays that are longer than LLC2 allows for bidirectional communication between hosts. Local acknowledgment addresses the problem of unpredictable time delays, multiple sendings, and lo ss of user sessions.

In a typical LLC2 session, when one host sends a frame to another host, the sending host expects the receiving host to respon d positi ve ly or ne gati v ely in a pred ef ined period of time commonly called th e T1 time. If the sending host does not receive an acknowledgment of the frame it sent within the T1 time, it retries a few times (normally 8 to 10). If there is still no response, the sending host drops the session.

Figure 127 illustrates an LLC2 session in which a 37x5 on a LAN segment communicates with a 3x74

on a different LAN segment separated via a wide-area backbone network. Frames are transported between Router A and Router B by means of DLSw+. However, the LLC2 session between the 37x5 and the 3x74 is still end-to-end; that is, every frame generated by the 37 x5 traverses the backbone ne twork to the 3x74, and the 3x74, on receipt of the frame, acknowledges it.

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SNA session

Figure 127 LLC2 Session without Local Acknowledgment

Technology Overview

Router B

Token

Ring

3x74

S1106a

37x5

Token

Ring

Router A

WAN

LLC2 session

SNA session

On backbone networks consisting of slow serial lin ks, the T1 timer on end hosts could e xpire before th e frames reach the remote hosts, causing the end host to resend . Resending results in duplicate frames reaching the remote host at the same time as the first frame reaches the remote host. Such frame duplication breaks the LLC2 protocol, resulting in the loss of sessions between the two IBM machines.

One way to solve this time delay is to increase the timeout value on the end nodes to account for the maximum transit time between the two end machines. However, in networks consisting of hundreds or even thousands of nodes, every machine would need to be reconfigured with new values. With local acknowledgment for LLC2 enabled, the LLC2 session between the two end nodes would not be not end-to-end, but instead, would terminate at two local routers. Figure 128 shows the LLC2 session with the 37x5 ending at Router A and the LLC2 session with the 3x7 4 ending at Router B. Bot h Router A and Router B execute the full LLC2 protocol as part of local acknowledgment for LLC2.

Figure 128 LLC2 Session with Local Acknowledgment

TCP session

7x5

Token

Ring

Router A

LLC2 session LLC2 session

WAN

Router B

Token

Ring

3x74

S1107a

With local ackno wledgment for LLC2 enabled in both routers, Router A ackno wledges frames received from the 37x5. The 37x5 still operates as if the acknowledgments it receives are from the 3x74. Router A looks like the 3x74 to the 37x5. Similarly, Router B acknowledges frames received from the 3x74. The 3x74 operates as if the acknowledgments it receives are from the 37x5. Router B looks like the 3x74 to 37x5. Because the frames do not have to travel the WAN backbone networks to be acknowledged, but are locally acknowledged by routers, the end machines do not time out, resulting in no loss of sessions.

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Technology Overview

Enabling local acknowledgment for LLC2 has the following advantages:

• Local acknowledgment for LLC2 solves the T1 timer problem without having to change any

configuration on the end nodes. The end nodes are unaware that the sessions are locally acknowledged. In networks consisting of hun dreds or even thousands of machines, this is a definite advantage. All the frames acknowledged by the Cisco IOS software appear to the end hosts to be coming from the remote IBM machine. In fact, by looking at a trace from a protocol analyzer, one cannot say whether a frame was acknowled ged by the l ocal router or by a remote IBM machin e. The MAC addresses and the RIFs generated by the Cisco IOS software are identical to those generated by the remote IBM machine. The only way to f ind out whet her a session is locally ack nowledged is to use either a show local-ack command or a show sourc e-bridge command on the router.

• All the supervisory (RR, RNR, REJ) frames that are locally acknowledged go no farther than the

router. Without local acknowledgment for LLC2, every frame traverses the backbone. With local acknowledgment, only data (I-frames) traverse the backbone, resulting in less traffic on

the backbone network. For installations in which customers pay for the amount of traffic passing through the backbone, this could be a de finite cost-saving measure. A simple p rotocol exists between the two peers to bring up or down a TCP session.

Notes on Using LLC2 Local Acknowledgment

Configuring Data-Link Switching Plus

LLC2 local acknowledgment is enabled with TCP and DLSw+ Lite remote peers. If the LLC2 session between the loca l host and the router terminates in either router, the other will be

informed to terminate its connection to its local host. If the TCP queue length of the connection between the two routers reaches the high-water mark, the

routers sends Receiver -Not- Ready (RNR) messages to the local hosts un ti l the queue limit is r educed to below this limit. It is possible, ho we ver, to prevent the RNR messages from being sent by using the dlsw llc2 nornr command.

The configuration of the LLC2 parameters for the local Token Ring interfaces can affect overall performance. Refer to the chapter “Configuring LLC2 and SDLC Pa rameters” in this manual for more details about fine-tuning your network through the LLC2 parameters.

The routers at each end of the LLC2 session execute the full LLC2 protocol, which could result in significant router overhead. The decision to use local acknowledgment for LLC2 should be based on the speed of the backbone network in relation to the Token Ring speed. For LAN segments separated by slow-speed serial links (for example, 56 kbps), the T1 timer problem could occur more frequently. In such cases, it might be wise to turn on local acknowledgment for LLC2. For LAN segments separated by a T1, backbone delays will be minimal; in such cases, DLSw+, FST or direct encapsulation should be considered in order to disable local acknowledgement. Speed mismatch between the LAN segments and the backbone network is one criterion to help you decide to use local acknowledgment for LLC2.

There are some situations (such as the receiving host failing between the time the sending host sends data and the time the receiving ho st recei ves it), i n which the sending host would determine, at the LLC2 layer, that data was recei ved when it actually was not. This error occurs because the router ackno wledges that it received data from the sending host before it determines that the receiving host can actually receive the data. But because both NetBIOS and SNA have error recovery in situations where an end device goes down, these higher-level protocols will resend any missing or lost data. Because these transaction request/confirmation prot ocols exist above LLC2, they are not affected by tight timers, as is LLC2. They also are transparent to local acknowledgment.

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If you are using NetBIOS applications, note that there are two NetBIOS timers—one at the link level and one at the next high er lev el. Local acknow ledgment for LLC2 is designed to solv e link timeouts only . If you are experiencing NetBIOS session timeouts, you have two options:

• Experiment with increasing your NetBIOS timers and decreasing your maximum NetBIOS frame

size.

• Avoid using NetBIOS applications on slow serial lines.

Note By default, the Cisco IOS software translates Token Ring LLC2 to Ethernet 802.3 LLC2. To

configure the router to translat e Token Ring LLC2 frames into Ethernet 0x80d5 format frames, refer to the section “Enable T ok en Ring LLC2-to-Ethernet Con v ersion” in the “Conf iguring Source-Ro ute Bridging” chapter of the Cisco IOS Bridging and IBM Networking Command Reference (Volume 1 of 2).

DLSw+ Support for Other SNA Features

DLSw+ can be used as a transport for SNA features such as LNM, DSPU, SNA service point, and SNA Switching Services (SNASw) through a Cisco IOS feature called virtual data-link control (VDLC).

LNM over DLSw+ allows DLSw+ to be used i n Token Ring networks that are managed by IBM’s LNM software. Using this feature, LNM can be used to manage Token Ring LANs, control access units, and Token Ring attached devices over a DLSw+ network. All management functions continue to operate as they would in a source-route bridged network or an RSRB network.

DSPU over DLSw+ allows Cisco’s DSPU feature to operate in conjunction with DLSw+ in the same router. DLSw+ can be used either upstream (toward the mainframe) or downstream (away from the mainframe) of DSPU. DSPU concentration consolidates the appearance of multiple PUs into a single PU appearance to VTAM , minimizing memory and cycles in central site resources (VTAM, NCP, and routers) and speeding network startup.

Technology Overview

SNA service point over DLSw+ allo ws Cisco’s SNA service point feature to be used in conjunction with DLSw+ in the same router. Using this feature, SNA service point can be configured in remote routers, and DLSw+ can provide the path for the remote service point PU to communicate with NetView. This allows full management visibility of resou rces from a NetView 390 console, while concurrently of fering the value-added features of DLSw+ in an SNA network.

SNASw ov er DLSw+ allows Cisco’ s APPN Branch Extender functionality to be used in conjunction with DLSw+ in the same router. With this feature, DLSw+ can be used to access SNASw in the data center. DLSw+ can also be used as a transport for SNASw upstream connectivity, providing nondisruptive recovery from failures.

Using DLSw+ as a transport for other Cisco IOS SNA features requires a feature called VDLC. Cisco I OS data-link users (such as LNM, DSPU, SNA service point, and SNASw) write to a virtual data-link control interface. DLSw+ then reads from this interface and sends out the traffic. Similarly, DLSw+ can receive traffic destined for one of these data-link users and write it to the virtual data-link control interface, from which the appropriate data-link user will read it.

In Figure 129, SNASw and DLSw+ use Token Ring and Ethernet, respectively, as “real” data-link controls, and use virtual data-link control to communicate between themselves. When one of the high-layer protocols passes data to the virtual data-link control, the virtual data-link control must pass it to a higher-layer protocol; nothing leaves the virtual data-link control without going through a data-link user.

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DLSw+ Configuration Task List

Figure 129 VDLC Interaction with Higher-Layer Protocols

Configuring Data-Link Switching Plus

DLSw+ Data-link users

Token Ring

SNASw

VDLC

The higher-layer protocols make no distinction between the VDLC and any other data-link control, but they do identify the VDLC as a destination. In the example shown in Figure 129, SNASw has two ports: a physical port for Token Ring and a virtual port for the VDLC. When you define the SNASw VDLC port, you can specify the MA C addr ess assigned to it. D ata transpor t from SNASw to DLSw+ by way of the VDLC is directed to the VDLC MAC address. The type of higher-layer protocol you use determines how the VDLC MAC address is assigned.

DLSw+ Configuration Task List

DLSw+ supports local or remote media conversion between LANs and SDLC or QLLC. To configure DLSw+, complete the tasks in the following sections:

• Defining a DLSw+ Local Peer for the Router, page 288

• Defining a DLSw+ Remote Peer, page 289

Ethernet

CLSI

Data-link contro

1909

• Mapping DLSw+ to a Local Data-Link Control, page 292

• Configuring Advanced Features, page 295

• Configuring DLSw+ Timers, page 310

See the “DLSw+ Configuration Examples” section on page 312 for examples.

Defining a DLSw+ Local Peer for the Router

Defining a DLSw+ local peer for a router enables DLSw+. Specify all local DLSw+ parameters as part of the local peer definition. To define a local peer, use the following command in global configuration mode:

Command Purpose

Router(config)# dlsw local peer [peer-id

ip-address] [group group] [border] [cluster cluster-id] [cost cost] [lf size] [keepalive seconds] [passive] [promiscuous] [init-pacing-window size] [max-pacing-window size] [biu-segment]

The following is a sample dlsw local peer statement:

dlsw local peer peer-id 10.2.34.3

Defines the DLSw+ local peer.

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Defining a DLSw+ Remote Peer

Defining a remote peer in DLSw+ is opti onal, ho we ver , usually at least one side o f a peer connection has a dlsw remote-peer statement. If you omit the dlsw remote-peer command from a DLSw+ peer configuration, then you must configure the promiscuous keyword on the dlsw local-peer statement. Promiscuous routers will accept any peer connection requests from other routers that are not preconfigured. To define a remote peer, use the dlsw remote-peer command in global configuration mode.

One of the options in the remote peer statement is to specify an encapsulation type. Configure one of the following types of encapsulations with the dlsw remote-peer statement:

• TCP Encapsulation, page 289

• TCP/IP with RIF Passthrough Encapsulation, page 290

• FST Encapsulation, page 290

• Direct Encapsulation, page 291

• DLSw Lite Encapsulation, page 291

Which encapsulation type you choose depends on several factors, including whether you want to terminate the LLC flows. TCP and DLSw+ Lite terminate the LLC, but the other encapsulation types do not. For details on each encapsulation type, see the DLSw+ Design and Implementation Guide. See the “Local Acknowledgement” section in the acknowledgement.

DLSw+ Configuration Task List

overview chapter of this publication for a discussion on local

TCP Encapsulation

To configure TCP encapsulation on a remote peer, use the following command in global configuration mode:

Command Purpose

Router(config)# dlsw remote-peer list-number tcp ip-address [ [ip-address | frame-relay interface serial number dlci-number | interface name]]

[bytes-netbios-out bytes-list-name] [circuit-weight weight] [cluster cluster-id] [cost cost] [dest-mac mac-address] [dmac-output-list access-list-number] [host-netbios-out host-list-name] [inactivity] [dynamic] [keepalive seconds] [lf size] [linger

minutes] [lsap-output-list list] [no-llc minutes] [passive] [priority] [rif-passthru

virtual-ring-number] [tcp-queue-max size] [timeout seconds]

The following command specifies a dlsw remote peer with TCP encapsulation:

dlsw remote-peer 0 tcp 10.23.4.5

Defines a remote peer with TCP encapsulation.

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DLSw+ Configuration Task List

TCP/IP with RIF Passthrough Encapsulation

To configure TCP/IP with RIF Passthrough encapsulation, use the following command in global configuration mode:

Command Purpose

Router(config)# dlsw remote-peer list-number tcp ip-address [backup-peer [ip-address | frame-relay interface serial number dlci-number

interface name]] [bytes-netbios-out

bytes-list-name] [circuit-weight weight] [cost cost] [dest-mac mac-address] [dmac-output-list access-list-number] [host-netbios-out host-list-name] [inactivity] [dynamic]

[keepalive seconds] [lf size] [linger minutes] [lsap-output-list list] [no-llc minutes] [passive] [priority] [rif-passthru virtual-ring-number] [tcp-queue-max size] [timeout seconds]

The following command specifies a remote peer with TCP/IP with RIF Passthrough encapsulation:

dlsw remote-peer 0 tcp 10.2.23.5 rif-passthru 100

Defines a remote peer with TCP/IP with RIF Passthrough encapsulation.

Configuring Data-Link Switching Plus

FST Encapsulation

To configure FST encapsulation on a remote peer, use the following command in global configuration mode:

Command Purpose

Router(config)# dlsw remote-peer list-number fst ip-address [backup-peer [ip-address |

frame-relay interface serial number dlci-number | interface name]] [bytes-netbios-out bytes-list-name] [circuit-weight weight] [cost cost] [dest-mac

mac-address] [dmac-output-list access-list-number] [host-netbios-out host-list-name] [keepalive seconds] [lf size] [linger minutes] [lsap-output-list list]

The following command specifies a DLSw remote peer with FST encapsulation:

dlsw remote-peer 0 fst 10.2.23.5

Defines a remote peer with FST encapsulation.

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Direct Encapsulation

To configure direct encapsulation, use the following command in global configuration mode:

Command Purpose

Router(config)# dlsw remote-peer list-number frame-relay interface serial number dlci-number [backup-peer [ip-address | frame-relay interface serial number dlci-number | interface name]]

[bytes-netbios-out bytes-list-name] [circuit-weight weight] [cost cost] [dest-mac

mac-address] [dmac-output-list access-list-number] [host-netbios-out

host-list-name] [keepalive seconds] [lf size] [linger minutes] [lsap-output-list list]

pass-thru

Direct encapsulation is supported over High-Level Data Link Control (HDLC) and Frame Relay. The following command specifies a DLSw remote peer with direct encapsulation over HDLC:

dlsw remote-peer 0 interface serial 01

Defines a remote peer with direct encapsulation.

DLSw+ Configuration Task List

Direct encapsulation over Frame Relay comes in two forms: DLSw Li te (LLC2 encap sulatio n) and Passthrough. Specifying the pass-thru option con figures the router so that the traffic will not be locally acknowledged. (DLSw+ normally locally acknowledges traffic to keep traffic on the WAN to a minimum.)

The following command specifies a DLSw remote peer with Direct encapsulation with pass-thru over Frame Relay:

dlsw remote-peer 0 frame-relay interface serial 01 pass-thru

DLSw+ Lite is described in the “DLSw Lite Encapsulation” section on page 291.

DLSw Lite Encapsulation

To configure DLSw Lite encapsulation, use the following command in global configuration mode:

Command Purpose

Router(config)# dlsw remote-peer list-number frame-relay interface serial number dlci-number [backup-peer [ip-address | frame-relay interface serial number dlci-number | interface name]]

[bytes-netbios-out bytes-list-name] [circuit-weight weight] [cost cost] [dest-mac

mac-address] [dmac-output-list access-list-number] [host-netbios-out host-list-name] [keepalive seconds] [lf size]

[linger minutes] [lsap-output-list list] pass-thru

Defines a remote peer with DLSw Lite encapsula tion.

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The following command specifies a DLSw remote peer with DLSw Lite encapsulation over Frame Relay:

dlsw remote-peer 0 frame-relay interface serial 01

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DLSw+ Configuration Task List

Mapping DLSw+ to a Local Data-Link Control

In addition to configuring local and remote peers, you must map one of the following local data-link controls to DLSw+:

• Token Ring, page 292

• Ethernet, page 293

• SDLC, page 293

• QLLC, page 294

• FDDI, page 295

Token Ring

Traffic that originates from Token Ring is source-route bridged from the local ring onto a source-bridge ring group and then picked up b y DLSw+. You must include a sour ce-bridge ring-gr oup command that specifies a virtual ring number when configuring Token Ring with DLSw+. In addition, you must configure the source-bridge command that tells the DLSw+ router to bridge from the physical Token Ring to the virtual ring.

Configuring Data-Link Switching Plus

To specify a virtual ring number, use the following command in global configuration mode:

Command Purpose

Router(config)# source-bridge ring-group ring-group [virtual-mac-address]

Defines a virtual ring.

To enable DLSw+ to bridge from the physical Token Ring ring to the virtual ring, use the following command in interface mode:

Command Purpose

Router(config-if)# source-bridge source-ring-number bridge-number

target-ring-number

Defines SRB on interface.

To enable single-route explorers, use the following command in interface mode:

Command Purpose

Router(config-if)# source-bridge spanning

Enables single-route explorers.

Configuring the source-bridge spanning command is required because DLSw+ uses single-route explorers by default.

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The following command configures a source-bridge ring-group and a virtual ring with a value of 100toDLSw+:

source-bridge ring-group 100 int T0

source-bridge 1 1 100 source-bridge spanning

The ring-group number specified in the source-bridge command must be the number of a defined source-bridge ring-group or DLSw+ will not see this interface.

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Ethernet

Traffic that originates from Ethernet is picked up from the local Ethernet interface bridge group and transported across the DLSw+ network. Therefore, you must map a specific Ethernet bridge group to DLSw+.

To map an Ethernet bridge group to DLSw+, use the following command in global configuration mode:

Command Purpose

Router(config)# dlsw bridge-group group-number [llc2 [N2 number] [ack-delay-time milliseconds] [ack-max number] [idle-time milliseconds] [local-window number] [t1-time milliseconds] [tbusy-time milliseconds] [tpf-time milliseconds] [trej-time milliseconds] [txq-max number] [xid-neg-val-time milliseconds] [xid-retry-time milliseconds]] [locaddr-priority

lu address priority list number] [sap-priority priority list number]

T o assign the Ethernet interface to a bridg e group, use the follo wing command in i nterface conf iguration mode:

Links DLSw+ to the bridge group of the Ethernet LAN.

DLSw+ Configuration Task List

Command Purpose

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

Assigns the Ethernet interface to a bridge group.

The following command maps bridge-group 1 to DLSw+:

dlsw bridge-group 1 int E1

bridge-group 1

bridge 1 protocol ieee

SDLC

Configuring SDLC devices is more complicated than configuring Ethernet and Token Ring. There are several considerations that affect which interface commands are configured. See the DLSw+ Design and Implementation Guide for more details.

To establish devices as SDLC stations, use the following commands in interface configuration mode:

Command Purpose

Step 1

Step 2

Step 3

Step 4

Step 5

Router(config-if)# encapsulation sdlc

Router(config-if)# sdlc role {none | primary | secondary | prim-xid-poll}

Router(config-if)# sdlc vmac

mac-address

Router(config-if)# sdlc address hexbyte [echo]

Router(config-if)# sdlc partner

mac-address sdlc-address {inbound | outbound}

Sets the encapsulation type of the serial interface to SDLC.

Establishes the role of the in terface.

Configures a MAC address for the serial interface.

Assigns a set of secondary stations attached to the serial link.

Specifies the destination address with which an LLC session is established for the SDLC station .

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Command Purpose

Step 6

Step 7

Router(config-if)# sdlc xid

Router(config-if)# sdlc dlsw {sdlc-address | default | partner mac-address [inbound | outbound]}

1. The last byte of the MAC address must be 00.

Configuring Data-Link Switching Plus

Specifies an XID value appropriate for the designated SDLC station associated with this serial interface.

Enables DLSw+ on an SDLC interface.

Use the default option if you have more than 10 SDLC devices to attach to the DLSw+ network. To configure an SDLC multidrop line downstream, you configure the SDLC role as either primary or

prim-xid-poll. SDLC role primary specifies that any PU without the xid-poll parameter in the sdlc address command is a PU 2.0 device. SDLC role prim-xid-poll specifies that e very PU is ty pe 2.1.

We recommend that you specify sdlc role primary if all SDLC devices are type PU 2.0 or a mix of PU 2.0 and PU 2.1. Specify sdlc role prim-xid-poll if all devices are type PU 2.1.

To configure DLSw+ to support LLC2-to-SDLC conversion for PU 4 or PU 5 devices, specify the echo option in the sdlc address command. A PU 4-to-PU 4 configuration requires that none be specified in the sdlc role command.

Refer to the “DLSw+ with SDLC Multidrop Support Configuration Examples” section on page 318 and the “DLSw+ with LLC2-to-SDLC Conversion Between PU 4-to-PU 4 Communication Example” section

on page 319 for sample configurations.

The following configuration shows a DLSw+ router configured for SDLC:

dlsw local-peer peer-id 10.2.2.2 dlsw remote-peer 0 tcp 10.1.1.1 interface Serial1 mtu 6000 no ip address encapsulation sdlc no keepalive nrzi-encoding clockrate 9600 sdlc vmac 4000.3745.0000 sdlc N1 48016 sdlc address 04 echo sdlc partner 4000.1111.0020 04 sdlc dlsw 4

QLLC

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SNA devices use QLLC when connecting to X.25 networks. QLLC essentially emulates SDLC over x.25. Therefore, configuring QLLC devices is also complicated. There are several considerations that affect which interface commands are configured. See the DLSw+ Design and Implementation Guide for details.

You can configure DLSw+ for QLLC connectivity, which enables both of the following scenarios:

• Remote LAN-attached devices (physical units) or SDLC-attached devices can access an FEP or an

AS/400 over an X.25 network. Our QLLC support allows remote X.25-attached SNA devices to access an FEP with out requiring

X.25 NCP Packet Switching Interface (NPSI) in the FEP. This may eliminate the requirement for NPSI (if GATE and DATE are not required), thereby eliminating the recurring license cost. In addition, because the QLLC attached devices appear to be Token Ring-attached to the Network Control Program (NCP), they require no preconf iguration in the FEP. Remote X.25-attached SNA devices can also connect to an AS/400 over Token Ring using this suppo rt.

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• Remote X.25-attached SNA devices can access an FEP or an AS/400 over a Token Ring or over

T o enable QLLC connectivity for DLSw+, use the follo wing commands in interf ace conf iguration mo de:

Command Purpose

Step 1

Step 2

Step 3

Step 4

Router(config-if)# encapsulation x 25

Router(config-if)# x25 address subaddress

Router(config-if)# x25 map qllc virtual-mac-addr x121-addr

[cud cud-value] [x25-map-options]

Router(config-if)# qllc dlsw {subaddress subaddress | pvc pvc-low [pvc-high]} [vmac vmacaddr [poolsize]] [partner partner-macaddr] [sap ssap dsap] [xid xidstring] [npsi-poll]

DLSw+ Configuration Task List

SDLC. For environments just beginning to migrate to LANs, our QLLC support allows deployment of

LANs in remote sites while maintaining access to the FEP over existing NPSI links. Remote LAN-attached devices (physical units) or SDLC-attached devices can access a FEP over an X.25 network without requiring X.25 hardware or software in the LAN-attached devices. The Cisco IOS software supports direct attachment to the FEP over X.25 without the need for routers at the data center for SNA traffic.

Specifies an interface as an X.25 device.

Activates X.25 subaddresses.

Associates a virtual MAC address with the X.121 address of the remot e X.25 device.

Enables DLSw+ over QLLC.

The following configuration enables QLLC connectivity for DLSw+:

dlsw local-peer peer-id 10.3.12.7 dlsw remote-peer 0 tcp 10.3.1.4 interface S0

encapsulation x25 x25 address 3110212011 x25 map qllc 1000.0000.0001 3 1104150101 qllc dlsw partner 4000.1151.1234

FDDI

Configure an FDDI interface the same as a Token Ring or Ethernet interface, depending on whether you are configuring SRB or Transparent Bridging. If you are configuring the router for SRB, configure the FDDI interface for T ok en Ring. If you are conf iguring the router for T ransparent Br idging, configur e the FDDI interface for Ethernet.

Configuring Advanced Features

DLSw+ goes beyond the standard to include additional functionality in the following areas:

• Scalability , page 296⎯Constructs IBM internetworks in a way that reduces the amount of broadcast

traffic, which enhances their scalability.

• Availability, page 303⎯Dynamically finds alternate paths and, optionally, load-balances across

multiple active peers, ports, and channel gateways.

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Scalability

Configuring Data-Link Switching Plus

• Modes of Operation, page 306⎯Dynamically detects the capabilities of the peer router and operates

according to those capabilities.

• Network Management, page 307—Works with enhanced network management tools such as

CiscoW orks Blue Maps, CiscoWorks SNA V iew, and CiscoWorks Blue Internetw ork Status Monitor (ISM).

• Traffic Bandwidth and Queueing Management, page 307—Offers several bandwidth management

and queueing features to enhance the overall performance of your DLSw+ network. Controls different types of explorer traffic using multiple queues, each with a wide range of depth settings.

• Access Control, page 307—Provides access control to various resources throughout a network.

One significant factor that limits the size of Token Ring internet works is the amount of explorer traffic that traverses the WAN. DLSw+ includes the following features to reduce the number of explorers:

• Peer Groups and Border Peers, page 296

• Explorer Firewalls, page 300

• NetBIOS Dial-on-Demand Routing, page 300

• SNA Dial-on-Demand Routing, page 301

• UDP Unicast Feature, page 301

• LLC1 Circuits, page 302

• Dynamic Peers, page 302

• Promiscuous Peer Defaults, page 302

Peer Groups and Border Peers

Perhaps the most significant optimization in DLSw+ is a feature kn own as peer groups. Peer groups are designed to address the broadcast replication that occurs in a fully meshed network. When any-to-any communication is required (for example, for NetBIOS or Advanced Peer-to-Peer Networking [APPN] environments), RSRB or standard DLSw implementations require peer connections between every pair of routers. This setup is not only difficult to configure, but it results in branch access routers having to replicate search requests for each peer connection. This setup wastes bandwidth and router cycles. A better concept is to group routers into cl usters and designate a focal router t o be responsible for broadcast replication. This capability is included in DLSw+.

With DLSw+, a cluster of routers in a region or a division of a company can be combined into a peer group. Within a peer group, one or more of the ro uters is d esignated to be th e border peer. Inst ea d of all routers peering to one another, each router within a group peers to the border peer; and border peers establish peer connections with each other. When a DLSw+ router receives a TEST frame or NetBIOS NAME-QUERY, it sends a single explorer frame to its border peer. The DLSw+ border peer router checks its local, remote and group cache for any reachability information before forwarding the explorer . If no match is found, the border peer forwards the explorer on behalf of the peer group member. If a match is found, the border peer sends the explorer to the appropriate peer or border peer. This setup eliminates duplicate explorers on the access links and minimizes the processing required in access routers.

You can further segment DLSw+ routers within the same border peer group that are serving the same LANs into a peer cluster. This segmentation reduces explorers because the border peer recognizes that it only has to forward an explorer to one member within a peer cluster. Only TCP encapsulation can be used with the DLSw+ Peer Clusters feature.

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The DLSw+ Peer Clusters feature is configured locally on the member peer or on a border peer . Although both options can be configured, we recommend that the cluster-id of a particular peer is defined in either the border peer or on the member peer, but not both because of potential configuration confusion.

DLSw+ Configuration Task List

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DLSw+ Configuration Task List

To define peer groups, configure border peers and assign the local peer to a peer cluster, use the following command in global configuration mode:

Command Purpose

Router(config)# dlsw local-peer [peer-id ip-address] [group group] [border] [cost cost] [cluster cluster-id] [lf size] [keepalive seconds] [passive] [promiscuous] [biu-segment] [init-pacing-window size] [max-pacing-window size]

Use the group keyword to define a peer group, the border keyword to define a border peer and the cluster keyword to assign the local peer to a peer cluster. When the user defines the cluster option in

the dlsw local-peer command on the member peer router, the cluster information is exchanged with the border peer during the capabilities exchange as the peers become active. The border peer uses this information to make explorer replication and forwarding decisions.

The following command configures the router as the Border peer that is a member of group 2:

dlsw local-peer peer-id 10.2.13.4 group 2 border

Enables peer groups and border peers.

Configuring Data-Link Switching Plus

Configure the cluster option in the dlsw remote-peer command on a border peer to enable the DLSw+ Peer Clusters feature without forcing every DLSw+ router in the network to upgrade their software. To enable the DLSw+ Peer Clusters feature on a Border Peer, use the following command in global configuration mode:

Command Purpose

Router(config)# dlsw remote-peer list-number tcp ip-address [backup-peer [ip-address | frame-relay interface serial number dlci-number

interface name]] [bytes-netbios-out

bytes-list-name] [circuit-weight weight] [cluster cluster-id] [cost cost] [dest-mac mac-address] [dmac-output-list access-list-number] [host-netbios-out host-list-name] [inactivity] [dynamic]

[keepalive seconds] [lf size] [linger minutes] [lsap-output-list list] [no-llc minutes] [passive] [priority] [rif-passthru virtual-ring-number] [tcp-queue-max size] [timeout seconds]

Defines the border peer router as part of a particular cluster and enables the DLSw+ Peer Clusters feature.

The following command configures a border router as a member of cluster 5:

dlsw remote-peer tcp 10.2.13.5 cluster 5

A peer-on-demand peer is a non-configured remote-peer that was connected because of an LLC2 session established through a border peer DLSw+ network. On-demand peers greatly reduce the number of peers that must be configured. You can use on-demand peers to establish an end-to-end ci rcuit e ven though the DLSw+ routers servicing the end systems have no specific configuration information about the peers. This configuration permits casual, any-to-any connection without the burden of configuring the connection in advance. It also allows an y-to -an y switching in large internetworks where pers is te nt TCP connections would not be possible.

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To configure peer-on-demand defaults, use the following command in global configuration mode:

Command Purpose

Router(config)# dlsw peer-on-demand-defaults [fst] [bytes-netbios-out bytes-list-name] [cost cost] [dest-mac destination mac-address] [dmac-output-list access-list-number] [host-netbios-out host-list-name] [inactivity minutes] [keepalive seconds] [lf size] [lsap-output-list list] [port-list port-list-number] [priority] [tcp-queue-max]

To define the maximum entries maintained in a border peer’s group cache, use the following command in global configuration mode:

Command Purpose

Router(config)# dlsw group-cache max-entries

number

Configures peer-on-demand defaults.

Defines the maximum entries in a group cache.

DLSw+ Configuration Task List

To remove all entries from the DLSw+ reachability cache, use the following command in privileged EXEC mode:

Command Purpose

Router# clear dlsw reachability

Removes all entries from the DLSw+ reachability cache.

To reset to zero the number of frames that have been processed in the local, remote and group caches, use the following command in privileged EXEC mode:

Command Purpose

Router# clear dlsw statistics

Resets to zero the number of frames that have been processed in the local, remote, and group caches.

To disable the border peer caching feature, use the following command in global configuration mode:

Command Purpose

Router(config-if)# dlsw group-cache disable

Disables the border peer caching feature.

To verify that the peer cluster feature is enabled or that the border peer is configured, issue the show dlsw capabilities command on the router . To verify the cluster id number of which the peer is a member, issue the show dlsw capabilities local command on the local router.

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To display the contents of the reachability caches, use the following command in privileged EXEC command mode:

Command Purpose

Router# show dlsw reachability [[group [value] | local | remote] | [mac-address [address] [netbios-names [name]

Use the group keyword to display the reachability information for the border peer.

Explorer Firewalls

An explorer fire wall permits only a single expl orer for a particular destination MA C address or NetBIOS name to be sent across the WAN. While an explorer is outstanding and awaiting a response from the destination, subsequent explorers for that MAC address or NetBIOS name are merely stored. When the explorer response is received at the originating DLSw+, all explorers receive an immediate local response. This eliminates the start-of-day explorer storm that many networks experience. Configure the dlsw timer command to enable explorer firewalls. See the “Configuring DLSw+ Timers” section on

page 310 for details of the command.

Displays content of group, local and remote caches.

Configuring Data-Link Switching Plus

To enable explorer firewalls, use the following command in global configuration mode:

Command Purpose

Router(config)# dlsw timer {icannotreach-block-time | netbios-cache-timeout | netbios-explorer-timeout | netbios-group-cache | netbios-retry-interval |

netbios-verify-interval | sna-cache-timeout | explorer-delay-time | sna-explorer-timeout | explorer-wait-time | sna-group-cache | sna-retry-interval | sna-verify-interval} time

Tunes an existing configuration parameter.

NetBIOS Dial-on-Demand Routing

This feature allows you to transport NetBIOS in a dial-on-demand routing (DDR) environment by filtering NetBIOS Session Alive packets from the WAN. NetBIOS periodically sends Session Alive packets as LLC2 I-frames. These packets do not require a response and are superfluous to the function of proper data flow. Furthermore, these packets keep dial-on-demand interfaces up and this up time causes unwanted per-packet charges in DDR networks. By filtering these NetBIOS Session Alive packets, you reduce traffic on the WAN and you reduce some costs that are associated with dial-on-demand routing.

To enable NetBIOS DDR, use the following command in global configuration mode:

Command Purpose

Router(config)# dlsw netbios keepalive-filter

Enables NetBIOS DDR.

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The following command enables NetBIOS DDR:

dlsw netbios keepalive-filter

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SNA Dial-on-Demand Routing

This feature allows you to run DLSw+ over a switched line and have the Cisco IOS software take the switched line down dynamically when it is not in use. Utilizing this feature gives the IP Routing table more time to converge when a network problem hinders a remote peer connection. In small networks with good IP convergence time and ISDN lines that start quickly, it is not as necessary to use the keepalive option. To use this feat ure, you must set th e keepalive value to zero, and you may need to use a lower value for the timeout option than the default, which is 90 seconds.

To configure SNA DDR, use the following command in global configuration mode:

Command Purpose

Router(config)# dlsw remote-peer list-number tcp ip-address [backup-peer [ip-address | frame-relay interface serial number dlci-number

interface name]] [bytes-netbios-out

bytes-list-name] [circuit-weight weight] [cluster cluster-id] [cost cost] [dest-mac mac-address] [dmac-output-list access-list-number] [host-netbios-out host-list-name] [inactivity] [dynamic]

[keepalive seconds] [lf size] [linger minutes] [lsap-output-list list] [no-llc minutes] [passive] [priority] [rif-passthru virtual-ring-number] [tcp-queue-max size] [timeout seconds]

Configures SNA DDR.

DLSw+ Configuration Task List

The following command configures the SNA DDR feature:

dlsw remote-peer 0 tcp 10.2.13.4 keepalive 0

UDP Unicast Feature

The UDP Unicast feature sends the SSP address resolution packets via UDP unicast service rather than TCP. (SSP packets include: CANUREACH_EX, NETBIOS_NQ_ex, NETBIOS_ANQ, and DAT AFRAME.) The UDP unicast feature allows DLSw+ to better control address resolution packets and unnumbered information frames during periods of congestion. Previously, these frames were carried over TCP. TCP resends frames that get lost or delayed in transit, and hence aggravate congestion. Because address resolution packets and unnumbered information frames are not sent on a reliable transport on the LAN, sending them reliably over the WAN is unnecessary. By using UDP for these frames, DLSw+ minimizes network congestion.

Note UDP unicast enhancement has no affect on DLSw+ FST or direct peer encapsulation.

This feature is enabled by default. To disable User Datagram Protocol (UDP) Unicast, use the following command in global configuration mode:

Command Purpose

Router(config)# dlsw udp-disable

Disables UDP Unicast.

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DLSw+ Configuration Task List

LLC1 Circuits

Support for LLC1 circuits more efficiently transports LLC1 UI traffic across a DLSw+ cloud. With LLC1 circuit support, the LLC1 unnumbered information frames (UI) are no longer subject to input queueing and are guaranteed to traverse the same path for the duration of the flo w . This featur e improv es transportation of LLC1 UI traffic because there is no longer the chance of having a specifically routed LLC1 UI frame broadcast to all remote peers. The circuit establishment process has not changed except that the circuit is established as soon as the specifically routed LLC1 UI frame is received and the DLSw+ knows of reachability for the destination MAC address. Furthermore, the connection remains in the CIRCUIT_EST ABLISHED state (rather than proceeding to the CONNECT state) until there is no UI frame flow for a MAC/SAP pair for 10 minutes.

This feature is enabled by default.

Dynamic Peers

In TCP encapsulation, the dynamic option and its suboptions no-llc and inactivity allo w you to specify and control the activation of dynamic peers, which are configured peers that are activated only when required. Dynamic peer connections are established only when there is DLSw+ data to send. The dynamic peer connections are taken down when th e last LLC2 connection using them terminates and the time period specified in the no-llc option expires. You can also use the inactivity option to take down dynamic peers when the circuits using them are inactive for a specified number of minutes.

Configuring Data-Link Switching Plus

Note Because the inactivity option may cause active LLC2 sessions to be term inated, you should not use

this option unless you want active LLC2 sessions to be terminated.

To configure a dynamic peer, use the following command in global configuration mode:

Command Purpose

Router(config)# dlsw remote-peer list-number tcp ip-address [backup-peer [ip-address | frame-relay interface serial number dlci-number

| interface name]] [bytes-netbios-out bytes-list-name] [circuit-weight weight] [cluster cluster-id] [cost cost] [dest-mac mac-address] [dmac-output-list access-list-number] [host-netbios-out host-list-name] [inactivity] [dynamic]

[keepalive seconds] [lf size] [linger minutes] [lsap-output-list list] [no-llc minutes] [passive] [priority] [rif-passthru virtual-ring-number] [tcp-queue-max size] [timeout seconds]

Configures a dynamic peer.

The following command specifies a dynamic peer with TCP encapsulation:

dlsw remote-peer 0 tcp 10.23.4.5 dynamic

Promiscuous Peer Defaults

If you do not configure a dlsw remote-peer statement on the DLSw+ router, then you must specify the promiscuous keyword on the dlsw local-peer statement. The promiscuous keyword enables the router to accept peer connection requests from those routers that are not preconfigured. Setting the dlsw prom-peer-defaults command allows the user to determine various settings for the promiscuous

transport.

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To configure promiscuous peer defaults, use the following command in global configuration mode :

Command Purpose

Router(config)# dlsw prom-peer-defaults [bytes-netbios-out bytes-list-name] [cost cost] [dest-mac destination-mac-address] [dmac-output-list access-list-number] [host-netbios-out host-list-name] [keepalive seconds] [lf size] [lsap-output-list list] [tcp-queue-max size]

Configures promiscuous peer defaults.

Availability

DLSw+ supports the following features that allow it to dynamically finds alternate paths quickly and optionally load balances across multiple active peers, ports, and channel gateways:

• Load Balancing, page 303

• Ethernet Redundancy, page 305

• Backup Peers, page 305

DLSw+ Configuration Task List

Load Balancing

DLSw+ offers enhanced availability by caching multiple paths to a given MAC address or NetBIOS name (where a path is either a remote peer or a local port). Maint aining mul tiple paths per destination is especially attractive in SNA networks. A common technique used in the hierarchical SNA environment is assigning the same MAC address to different Token Ring interface couplers (TICs) on the IBM FEPs. DLSw+ ensures that duplicate TIC addresses are found, and, if multiple DLSw+ peers can be used to reach the FEPs, they are cached.

The way that multiple capable peers are handled with DLSw+ can be configured to meet either of the following network needs:

• Fault tolerance—To rapidly reconnect if a data-link connection is lost. If load balancing is not

enabled, the Cisco IOS software, by default, maintains a preferred path and one or more capable paths to each destination. The preferred path is either the peer or port that responds first to an explorer frame or the peer with the least cost. If the preferred path to a given destination is unavailable, the next available capable path is promoted to the new preferred path. No additional broadcasts are required, and recovery through an alternate peer is immediate. Maintaining multip le cache entries facilitates a timely reconnection after session outages.

A peer with the least cost can also be the preferred path. Y ou can specify cost in either the dlsw local peer or dlsw remote peer commands. See the DLSw+ Design and Impl ementation Guide for details on how cost can be applied to control which path sessions use.

• Load balancing—To distribute the network traffic over multiple DLSw+ peers in the network.

Alternately, when there are duplicate paths to the destination end system, you can configure load balancing. DLSw+ alternates new circuit requests in either a ro und-robin or enhanced load balancing fashion through the list of capable peers o r ports. If round-robin is configured, the router distributes the new circuit in a round-robin fashion, basing it’s decision on which peer or port established the last circuit. If enhanced load balancing is configured, the router distributes new circuits based on existing loads and the desired ratio. It detects the path that is underloaded in comparison to the other capable peers and wil l assign ne w ci rcuits to that path until the d esired ratio is achieved.

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DLSw+ Configuration Task List

For multiple peer connections, peer costs must be applied. The DLSw+ Enhanced Load Balancing feature works only with the lowest (or equal) cost peers. For e xample, if the user specif ies dlswrt r1, dlswrtr2 and dlswrtr3 with costs of 4, 3, and 3 respectively, DLSw+ establishes new circuits with only dlswrtr 2 and dlswrtr3.

T o enab le the DLSw+ Enha nced Load Ba lancing fea ture on the lo cal router, use the following command in global configuration mode:

Command Purpose

Router(config)# dlsw load-balance [round-robin | circuit count circuit-weight]

To adjust the circuit weight for a remote peer with TCP encapsulation, use the following command in global configuration mode:

Command Purpose

Router(config)# dlsw remote-peer tcp [circuit-weight value]

Configures the DLSw+ Enhanced Load Balancing feature on the local router.

Adjusts the circuit weight on the remote peer.

Configuring Data-Link Switching Plus

To adjust the circuit weight for a remote peer with DLSw+ Lite encapsulation, use the following command in global configuration mode:

Command Purpose

Router(config)# dlsw remote-peer frame-relay interface serial number dlci number [circuit-weight value]

Adjusts the circuit weight on the remote peer.

The circuit-weight of a remote peer controls the number of circuits that peer can take. If multiple, equally low-cost peers can reach a remote source, the circuits to that remote source are distributed among the remote peers based on the ratio of thei r configured circuit-weights. The peer with the highest circuit-weight takes more circuits.

Because a DLSw+ peer selects its new circuit paths from within its reachability cache, the user must configure the dlsw timer explorer-wait-time command with enough time to allow for all the explorer responses to be received. If the new DLSw+ Enhanced Load Balancing Feature is enabled, a messag e is displayed on the console to alert the user if the timer is not set.

To configure the amount of time needed for all the explorer responses to be received, use the following command in global configuration mode:

Command Purpose

Router(config)# dlsw timer {explorer-wait-time}

Sets the time to wait for all stations to respond to explorers.

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See the DLSw+ Design and Implementation Guide for details on how to configure load balancing in DLSw+. Refer to the “DLSw+ with Enhanced Load Balanc ing Configuratio n Example” sec tion on

page 327 for a sample configuration.

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Ethernet Redundancy

The DLSw+ Ethernet Redundancy feature, introduced in Cisco IOS Release 12.0(5)T, provides redundancy and load balancing between multiple DLSw+ peers in an Ethernet environment. It enables DLSw+ to support parallel paths between two points in an Ethernet environment, ensuring resiliency in the case of a router failure and pro viding load balancing for traf fic load. The feature also enables DLSw+ to support multiple DLSw+ routers on the same transparent bridged domain that can reach the same MAC address in a switched environment

To enable the DLSw+ Ethernet Redundancy feature, issue the following command in interface configuration mode:

Command Purpose

Router(config-if)# dlsw transparent redundancy-enable

Configures transparent redundancy.

To enable the DLSw+ Ethernet Redundancy feature in a switched environment, enter the following commands in interface configuration mode:

DLSw+ Configuration Task List

Step 1

Step 2

Command Purpose

Router(config-if)# dlsw transparent switch-support

Router(config-if)# dlsw transparent map local mac mac address remote mac mac address neighbor mac address

Enables DLSw+ Ethernet Redundancy feature when using a switch device.

Configures a single destination MAC address to which multiple MAC addresses on a transparent bridged are mapped.

The Ethernet Redundancy feature is a complex feature. See the DLSw+ Design and Implementation Guide for more details. Refer to the “DLSw+ with Ethernet Redundancy Configuration Example”

section on page 331 and the “DLSw+ with Ethernet Redundancy Enabled for Switch Support Configuration Example” section on page 332 for sample configurations.

Backup Peers

The backup-peer option is common to all encapsulation types on a remote peer and specifies that this remote peer is a backup peer for the router with the specified IP-address, Frame Relay Data-Link Control Identifier (DLCI) number, or interface name. When the primary peer fails, all circuits ov er this peer are disconnected and the user can start a new session via their backup peer. Prior to Cisco IOS Release 11.2(6)F, you could configure backup peers only for primary FST and TCP.

Also, when you specify the backup-peer option in a dlsw remote-peer tcp command, the backup peer is activated only when the primary peer becomes unreachable. Once the primary peer is reactivated, all new sessions use the primary peer and the backup peer remains active only as long as there are LLC2 connections using it. You can use the linger option to specify a period (in mi nutes) that t he backu p peer remains connected after the connection to the primary peer is reestablished. When the linger period expires, the backup peer connection is taken down.

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DLSw+ Configuration Task List

Note If the linger keyword is set to 0, all existing sessions on the backup router immediately drop when

the primary recovers. If the linger keyword is omitted, all existing sessions on the backup router remain active (as long as the session is active) when the primary recovers, ho wever, all new sessions establish via the primary peer. If the linger keyword is set to x minutes, all existing sessions on the backup router remain active for x minutes once the primary recovers, howev er, all ne w sessions establish via the primary peer. Once x minutes expire, all existing sessions on the backup router drop and the backup peer connection is terminated. The linger keyword can be used to minimize line costs if the backup peer is accessed over dial lines, but can be set high enough to allow an operator warning to be sent to all the SNA end users. It will not, however, pass explorers and will not create any new circuits while the primary is up.

To configure a backup peer, use the following command in global configuration mode:

Command Purpose

Router(config)# dlsw remote peer backup-peer

ip-address

Configures a backup peer.

Configuring Data-Link Switching Plus

Modes of Operation

It is sometimes necessary for DLSw+ and RSRB to coexist in the same network and in the same router (for example, during migration from RSRB to DLSw+). Cisco DLSw+ supports this environment. In addition, DLSw+ must also interoperate with other vendor s’ implementations that are based upon other DLSw RFC standards, such as DLSw Version 1 and Version 2.

Cisco routers, implementing Cisco DLSw+, automatically supports three different modes of operation:

Note DLSw+ does not interoperate with the DLSw RFC 1434 standard.

Some enhanced DLSw+ features are also available when a Cisco router is operating in standards compliance mode with another vendor’s router. In particular, enhancements that are locally controlled options on a router can be accessed even though the remote router does not have DLSw+. These include reachability caching, explorer firewalls and media conversion.

• Dual mode⎯A Cisco router can communicate with so me remote peers using RSRB and with others

using DLSw+, providing a smooth migration path from RSRB to DLSw+; in dual mode, RSRB and DLSw+ coexist on the same box; the local peer must be config ured for both RSRB and DLSw+; and the remote peers must be configured for either RSRB or DLSw, but not both.

• Standards compliance mode⎯DLSw+ can detect automatically (via the DLSw capabilities

exchange) if the participating router is manufactured by another vendor, therefore operating in DLSw standard mode (DLSw Version 1 RFC 1795 and DLSw Version 2 RFC 2166).

• Enhanced mode⎯DLSw+ can detect automatically that the participating router is another DLSw+

router, therefore operating in enhanced mode, making all of the features of DLSw+ available to the SNA and NetBIOS end systems.

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Network Management

There are several network management tools available to the user to help them more easily manage and troubleshoot their DLSw+ network. CiscoWorks Blue Maps provides a logical view of the portion of your router network relevant to DLSw+ (there is a similar tool for RSRB and APPN). CiscoWorks Blue SNA V iew ad ds to the information provided by Maps b y correlating SNA PU and LU names with DLSw+ circuits and DLSw+ peers. CiscoWorks Blue Internetwork Status Monitor (ISM) support allows you to manage your router network from the mainframe console using IBM’s NetView or Sterling’s SOLVE:Netmaster. See the DLSw+ Design and Implementation Guide “Using CiscoWorks Blue: Maps, SNA View, and Internetwork Status Monitor” chapter for more details.

Traffic Bandwidth and Queueing Management

Cisco offers several bandwidth management and queueing features (such as DLSw+ RSVP) to enhance the overall performance of your DLSw+ net work. The queueing and bandwidth management f eatures are described in detail in the DLSw Design and Implementation Guide “Ban dwidth Management Queu eing” chapter.

Access Control

DLSw+ Configuration Task List

DLSw+ offers the following features that allow it to control access to various resources throughout a network:

• DLSw+ Ring List or Port List, page 307

• DLSw+ Bridge Group List, page 308

• Static Paths, page 309

• Static Resources Capabilities Exchange, page 309

• Filter Lists in the Remote-Peer Command, page 309

DLSw+ Ring List or Port List

DLSw+ ring lists map traffic on specific local rings to remote peers. You can create a ring list of local ring numbers and apply the list to remote peer definitions. Traffic received from a remote peer is only forwarded to the rings specified i n the ring list. Traffic received from a local interf ace is only for ward ed to peers if the input ring number appears in the ring list applied to the remote peer definition. The definition of a ring list is optional. If you want all peers and all rings to receive all traffic, you do not have to define a ring list. Simply specify 0 for the list number in the remote peer statement.

To define a ring list, use the following command in global configuration mode:

Command Purpose

Router(config)# dlsw ring-list list-number rings ring-number

Defines a ring list.

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DLSw+ port lists map traffic on a local interface (either Token Ring or serial) to remote peer s. Port lists do not work with Ethernet interfaces, or any other interface types connected to DLSw+ by means of a bridge group. You can create a port list of local ports and apply the list to remote peer definitions. Traff ic received from a remote peer is only forwarded to peers if the input port number appears in the port list applied to the remote peer definition. The por t list comman d pro vides a si ngle command t o specify b oth serial and Token Ring interfaces. Figure 130 shows how port lists are used to map traffic.

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DLSw+ Configuration Task List

Figure 130 Mapping Traffic Using Port Lists

Configuring Data-Link Switching Plus

Token

Ring

Token

Ring

Port list 2

Peer A

Token

Ring

Port list 1

Peer B: Port list 1 Peer C: Port list 2

The definition of a port list is optional. If you want all peers and all interfaces to receive all traffic, you do not have to define a port list. Simply specify 0 for the list number in the remote peer statement.

To define a port list, use the following command in global configuration mode:

Command Purpose

Router(config)# dlsw port-list list-number type number

Defines a port list.

Peer B

Peer C

Explorer

Token

Ring

51860

Note Either the ring list or the port list command can be used to associate rings with a given ring list. The

ring list command is easier to type in if you have a large number of rings to define.

DLSw+ Bridge Group List

DLSw+ bridge group lists map traffic on the local Ethernet bridge group interface to remote peers. You can create a bridge group list and apply the list to remote peer definitions. T raff ic recei ved from a remote peer is only forwarded to the bridge group specified in the bridge group list. T raf fic recei ved from a local interface is only forwarded to peers if the input bridge group number appears in the bridge group list applied to the remote peer definition. The definition of a bridge group list is optional. Because each remote peer has a single list number associated with it, if you want traffic to go to a bridge group and to either a ring list or port list, you should specify the same list number in each definition

To define a bridge-group list, use the following command in global configuration mode:

Command Purpose

Router(config)# dlsw bgroup-list list-number bgroups number

Defines a ring list.

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Static Paths

Static path definitions allow a router to setup circuits without sending explorers. The path specifies the peer to use to access a MAC address or NetBIOS name.

To configure static paths to minimize explorer traffic originating in this peer, use one of the following commands in global configuration mode, as needed:

Command Purpose

Router(config)# dlsw mac-addr mac-addr {ring ring number | remote-peer {interface serial number | ip-address ip-address} | rif rif string | group group}

Configures the location or path of a static MAC address.

DLSw+ Configuration Task List

Router(config)# dlsw netbios-name netbios-name {ring ring number | remote-peer {interface

serial number | ip-address ip-address} | rif rif string | group group}

Configures a static NetBIOS name.

Static Resources Capabilities Exchange

T o reduce explorer traff ic destined for this peer , the peer can send other peers a list of resources for which it has information (icanreach) or does not have information (icannotreach). This information is exchanged as part of a capabilities exchange.To configure static resources that will be exchanged as part of a capabilities exch ange, use one of the fo llowing commands in global configuration mode, as needed:

Command Purpose

Router(config)# dlsw icannotreach saps sap

[sap...]

Router(config)# dlsw icanreach {mac-exclusive | netbios-exclusive | mac-address mac-addr [mask mask] | netbios-name name |

saps}

Configures a resource not locally reachable by the router.

or Configures a resource locally reachable by the router.

Filter Lists in the Remote-Peer Command

The dest-mac and dmac-output-list options allow you to specify filter lists as part of the dlsw remote-peer command to control access to remote peers. For static peers in direct, FST, or TCP

encapsulation, these filters control which explorers are sent to remote peers. For dynamic peers in TCP encapsulation, these filters also control the activ ation of the dynamic peer. For example, you can specify at a branch office that a remote peer is activated only when there is an explorer frame destined for the Media Access Control (MAC) address of an FEP.

The dest-mac option permits the connection to be established only when there is an explorer frame destined for the specified MAC address. The dmac-output-list option permits the connection to be established only when the explorer frame passes the specified access list. To permit access to a single MAC address, use the dest-mac option, because it is a configuration “shortcut” compared to the dmac-output-list option.

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Configuring DLSw+ Timers

To configure DLSw+ timers, use the following command in global configuration mode:

Command Purpose

Router(config)# dlsw timer {icannotreach-block-time | netbios-cache-timeout | netbios-explorer-timeout | netbios-group-cache |netbios-retry-interval |

netbios-verify-interval |sna-cache-timeout | sna-explorer-timeout | sna-group-cache | sna-retry-interval | sna-verify-interval} time

Configures DLSw+ timers.

See the DLSw+ Design and Implementation Guide “Customization” chapter and the Cisco IOS Bridging and IBM Networking Command Reference (Volume 1 of 2) for command details.

Verifying DLSw+

Configuring Data-Link Switching Plus

T o verify th at DLSw+ is configured on the ro uter , use the followin g command in privile ged EXEC mode:

Command Purpose

Router# show dlsw capabilities local

Displays the DLSw+ configuration of a specific peer.

The following sample shows that DLSw+ is configured on router milan:

milan#show dlsw capabilities local DLSw:Capabilities for peer 1.1.1.6(2065) vendor id (OUI) :'00C' (cisco)

version number :1 release number :0 init pacing window :20 unsupported saps :none num of tcp sessions :1 loop prevent support :no icanreach mac-exclusive :no icanreach netbios-excl. :no reachable mac addresses :none reachable netbios names :none cisco version number :1 peer group number :0 border peer capable :no peer cost :3 biu-segment configured :no UDP Unicast support :yes local-ack configured :yes

priority configured :no Cisco Internetwork Operating System Software IOS GS Software (GS7-K-M), Experimental Version 11.1(10956) [sbales 139] Copyright (c) 1986-1996 by cisco Systems, Inc. Compiled Thu 30-May-96 09:12 by sbales8

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If only a command prompt appears, then DLSw+ is not configured for the router.

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Alternately, to verify that DLSw+ is configured, issue the following command in privileged EXEC mode:

Command Purpose

Router# show running configuration

The global DLSw+ configuration statements, including the dlsw local-peer statement, appear in the output before the interface configuration statements. The following sample shows that DLSw+ is configured on router milan:

milan# show run version 12.0 ! hostname Sample ! source-bridge ring-group 110 dlsw local-peer peer-id 10.1.1.1 promiscuous ! interface TokenRing0/0 no ip address ring-speed 16 source-bridge 222 1 110 source-bridge spanning !

Displays the running configuration of a device.

Monitoring and Maintaining the DLSw+ Network

To monitor and maintain activity on the DLSw+ network, use one of the following commands in privileged EXEC mode, as needed:

Command Purpose

Router# show dlsw capabilities interface type number

Router# show dlsw capabilities ip-address

ip-address

Router# show dlsw capabilities local

Router# show dlsw circuits

Router# show dlsw fastcache

Router# show dlsw local-circuit

Router# show dlsw peers

Router# show dlsw reachability

Router# dlsw disable

Router# show dlsw statistics [border-peers]

Router# clear dlsw circuit

1. Issuing the clear dlsw circuits command will cause the loss of any associated LLC2 sessions.

Displays capabilities of a direct-encapsulated remote peer.

Displays capabilities of a TCP/FST remote peer.

Displays capabilities of the local peer. Displays DLSw+ circuit information. Displays the fast cache for FST and direct-encapsulated peers. Displays DLSw+ circuit information when doing local

conversion. Displays DLSw+ peer information. Displays DLSw+ reachability information. Disables and re-enable DLSw+ without altering the conf iguration. Displays the number of frames that have been processed in the

local, remote, and group caches. Closes all the DLSw+ circuits1. Also used to reset to zero the

number of frames that have been processed in the local, remote, and group cache.

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DLSw+ Configuration Examples

See the DLSw+ Design and Implementation Guide “Using Sho w and Debug Commands” chapter and the Cisco IOS Bridging and IBM Networking Command Reference (Volume 1 of 2) for details of the

commands.

DLSw+ Configuration Examples

The following sections provide DLSw+ configuration examples:

• DLSw+ Using TCP Encapsulation and LLC2 Local Acknowledgment—Basic Configuration

Example, page 312

• DLSw+ Using TCP Encapsulation with Local Acknowledgment—Peer Group Configuration

Example 1, page 314

• DLSw+ Using TCP Encapsulation with Local Acknowledgment—Peer Group Configuration

Example 2, page 316

• DLSw+ with SDLC Multidrop Support Configuration Examples, page 318

• DLSw+ with LLC2-to-SDLC Conversion Between PU 4-to-PU 4 Communication Example,

page 319

• DLSw+ Translation Between Ethernet and Token Ring Configuration Example, page 320

Configuring Data-Link Switching Plus

• DLSw+ Translation Between FDDI and Token Ring Configuration Example, page 321

• DLSw+ Translation Between SDLC and Token Ring Media Example, page 322

• DLSw+ over Frame Relay Configuration Example, page 324

• DLSw+ over QLLC Configuration Examples, page 325

• DLSw+ with RIF Passthrough Configuration Example, page 326

• DLSw+ with Enhanced Load Balanc ing Configuration Exam ple, page 327

• DLSw+ Peer Cluster Feature Configuration Example, page 328

• DLSW+ RSVP Bandwidth Reservation Feature Configuratio n Example, pa ge 329

• DLSw+ RSVP Bandwidth Reservation Feature with Border Peers Conf iguration Example, page 330

• DLSw+ with Ethernet Redundancy Configuration Example, page 331

• DLSw+ with Ethernet Redundancy Enabled for Switch Support Configuration Example, page 332

DLSw+ Using TCP Encapsulation and LLC2 Local Acknowledgment—Basic Configuration Example

This sample configuration requires the following tasks, which are described in earlier sections of this document:

• Define a Source-Bridge Ring Group for DLSw+

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• Define a DLSw+ Local Peer for the Router

• Define DLSw+ Remote Peers

• Assign DLSw+ to a local data-link control

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Figure 131 illustrates a DLSw+ configuration with local acknowledgment. Because the RIF is

terminated, the ring group numbers do not have to be the same.

Figure 131 DLSw+ with Local Acknowledgment—Simple Configuration

DLSw+ Configuration Examples

Ring Group

7x5

Token

Ring

Router A

10.2.25.1 10.2.5.2

Router A

source-bridge ring-group 10 ! dlsw local-peer peer-id 10.2.25.1 dlsw remote-peer 0 tcp 10.2.5.2

interface loopback 0

ip address 10.2.25.1 255.255.255.0 ! interface tokenring 0

no ip address

ring-speed 16

source-bridge 25 1 10

source-bridge spanning

Router B

source-bridge ring-group 12 dlsw local-peer peer-id 10.2.5.2 dlsw remote-peer 0 tcp 10.2.25.1

interface loopback 0

ip address 10.2.5.2 255.255.255.0 ! interface tokenring 0

no ip address

ring-speed 16

source-bridge 5 1 12

source-bridge spanning

Ring Group

Router B

Token

Ring

S3241

3x74

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DLSw+ Configuration Examples

DLSw+ Using TCP Encapsulation with Local Acknowledgment—Peer Group Configuration Example 1

Figure 132 illustrates border peers with TCP encapsula tion. Router A is configured to operate in

promiscuous mode, and border peers Rout ers B and C fo rward broadcasts. Th is configuration reduces processing requirements in Router A (the access router) and still supports any-to-any networks. Configure Border peer B and C so that they peer to each other.

Figure 132 DLSw+ with Peer Groups Specified (Example 1)

Token

Ring

Router B

Router C

IP cloud

t3/0

t3/1

Token

Ring

Token

Ring

200

Router A

128.207.152.5

128.207.150.8

etBIOS

server

Group 70 Group 69

border

Router A

hostname Router A ! source-bridge ring group 31 dlsw local-peer peer-id 128.207.152.5 group 70 promiscuous dlsw remote peer 0 tcp 128.207.150.8 interface loopback 0 ip address 128.207.152.5 255.255.255.0 ! interface serial 0

ip unnumbered tokenring

clockrate 56000 ! interface tokenring 0

ip address 128.207.152.5 255.255.255.0

ring-speed 16

source-bridge 200 13 31

source-bridge spanning ! router igrp 777 network 128.207.0.0

128.207.169.3 border

NetBIOS

requester

3242

Router B

hostname Router B ! source-bridge ring-group 31 dlsw local-peer peer-id 128.207.150.8 group 70 border promiscuous dlsw remote-peer 0 tcp 128.207.169.3 interface loopback 0 ip address 128.207.150.8 255.255.255.0

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! interface serial 0

ip unnumbered tokenring 0

bandwidth 56 ! interface tokenring 0

ip address 128.207.150.8 255.255.255.0

ring-speed 16 source-bridge 3 14 31

source-bridge spanning ! router igrp 777 network 128.207.0.0

Router C

hostname Router C ! source-bridge ring-group 69 dlsw local-peer peer-id 128.207.169.3 group 69 border promiscuous dlsw remote-peer 0 tcp 128.207.150.8 interface loopback 0 ip address 128.207.169.3 255.255.255.0 ! interface tokenring 3/0 description fixed to flashnet

ip address 128.207.2.152 255.255.255.0

ring-speed 16

multiring all ! interface tokenring 3/1

ip address 128.207.169.3 255.255.255.0

ring-speed 16 source-bridge 33 2 69

source-bridge spanning ! router igrp 777 network 128.207.0.0

DLSw+ Configuration Examples

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DLSw+ Configuration Examples

DLSw+ Using TCP Encapsulation with Local Acknowledgment—Peer Group Configuration Example 2

Figure 133 illustrates a peer group configuration that allows any-to-an y connection except for Router B.

Router B has no connectivity to anything except router C because the promiscuous keyword is omitted.

Figure 133 DLSw+ with Peer Groups Specified (Example 2)

Router A

150.150.99.1

Token

Ring

Token

Ring

500

SDLC “01”

controller

FEPMainframe

Group 2

Token

Ring

Router C

150.150.100.1 S9

Router B

150.150.98.1

S1/0

Router D

Router A

hostname Router A ! source-bridge ring-group 2000 dlsw local-peer peer-id 150.150.99.1 group 2 promiscuous dlsw remote-peer 0 tcp 150.150.100.1 ! interface loopback 0

ip address 150.150.99.1 255.255.255.192 ! interface tokenring 0

no ip address

ring-speed 16 source-bridge 99 1 2000

source-bridge spanning ! router eigrp 202 network 150.150.0.0

T0/0

Token

Ring

S1/1

Token

Ring

Group 1

Token

Ring

T0/1

T0/2

150.150.96.1

150.150.97.1

Router E

Token

Ring

1861

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Router B

hostname Router B ! source-bridge ring-group 2000

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dlsw local-peer peer-id 150.150.98.1 group 2 dlsw remote-peer 0 tcp 150.150.100.1 ! interface loopback 0

ip address 150.150.98.1 255.255.255.192 ! interface serial 1

no ip address

encapsulation sdlc

no keepalive

clockrate 9600

sdlc role primary

sdlc vmac 4000.8888.0100

sdlc address 01

sdlc xid 01 05d20006

sdlc partner 4000.1020.1000 01

sdlc dlsw 1 ! interface tokenring 0

no ip address

ring-speed 16 source-bridge 98 1 2000

source-bridge spanning ! router eigrp 202 network 150.150.0.0

DLSw+ Configuration Examples

Router C

hostname Router C ! source-bridge ring-group 2000 dlsw local-peer peer-id 150.150.100.1 group 2 border promiscuous dlsw remote-peer 0 tcp 150.150.96.1 ! interface loopback 0

ip address 150.150.100.1 255.255.255.192 interface tokenring 0

no ip address

ring-speed 16

source-bridge 500 1 2000

source-bridge spanning ! router eigrp 202 network 150.150.0.0

Router D

hostname Router D ! source-bridge ring-group 2000 dlsw local-peer peer-id 150.150.96.1 group 1 border promiscuous dlsw remote-peer 0 tcp 150.150.100.1 ! interface loopback 0

ip address 150.150.96.1 255.255.255.192 ! interface tokenring 0/0

no ip address

ring-speed 16

source-bridge 96 1 2000

source-bridge spanning ! interface tokenring 0/1

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DLSw+ Configuration Examples

no ip address ring-speed 16 source-bridge 92 1 2000

source-bridge spanning ! .interface tokenring 0/2

no ip address

ring-speed 16

source-bridge 93 1 2000

source-bridge spanning ! router eigrp 202 network 150.150.0.0

Router E

hostname Router E ! source-bridge ring-group 2000 dlsw local-peer peer-id 150.150.97.1 group 1 promiscuous dlsw remote-peer 0 tcp 150.150.96.1 ! interface loopback 0

ip address 150.150.97.1 255.255.255.192 ! interface tokenring 0

no ip address

ring-speed 16

source-bridge 97 1 2000

source-bridge spanning ! router eigrp 202 network 150.150.0.0

Configuring Data-Link Switching Plus

DLSw+ with SDLC Multidrop Support Configuration Examples

In the following example, all devices are type PU 2.0:

interface serial 2 mtu 4400 no ip address encapsulation sdlc no keepalive clockrate 19200 sdlc role primary sdlc vmac 4000.1234.5600 sdlc address C1 sdlc xid C1 05DCCCC1 sdlc partner 4001.3745.1088 C1 sdlc address C2 sdlc xid C2 05DCCCC2 sdlc partner 4001.3745.1088 C2 sdlc dlsw C1 C2

The following example sho ws mixed PU 2.0 (device using address C1) and PU 2.1 (device using address C2) devices:

interface serial 2 mtu 4400 no ip address encapsulation sdlc no keepalive

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S6283

clockrate 19200 sdlc role primary sdlc vmac 4000.1234.5600 sdlc address C1 sdlc xid C1 05DCCCC1 sdlc partner 4001.3745.1088 C1 sdlc address C2 xid-poll

sdlc partner 4001.3745.1088 C2

sdlc dlsw C1 C2

In the following example, all devices are type PU 2.1 (Method 1):

interface serial 2 mtu 4400 no ip address encapsulation sdlc no keepalive clockrate 19200 sdlc role primary sdlc vmac 4000.1234.5600 sdlc address C1 xid-poll

sdlc partner 4001.3745.1088 C1

sdlc address C2 xid-poll

sdlc partner 4001.3745.1088 C2

sdlc dlsw C1 C2

DLSw+ Configuration Examples

In the following example, all devices are type PU 2.1 (Method 2):

interface serial 2 mtu 4400 no ip address encapsulation sdlc no keepalive clockrate 19200 sdlc role prim-xid-poll sdlc vmac 4000.1234.5600 sdlc address C1

sdlc partner 4001.3745.1088 C1 sdlc address C2 sdlc partner 4001.3745.1088 C2 sdlc dlsw C1 C2

DLSw+ with LLC2-to-SDLC Conversion Between PU 4-to-PU 4 Communication Example

The following example is a sample configuration for LLC2-to-SDLC conversion for PU 4-to-PU 4 communication as shown in Figure 134:

Figure 134 LLC2-to-SDLC Conversion for PU 4-to-PU 4 Communication

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Token

Ring

Frame Relay

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DLSw+ Configuration Examples

S3584

Router A

source-bridge ring-group 1111 dlsw local-peer peer-id 10.2.2.2 dlsw remote-peer 0 tcp 10.1.1.1 interface loopback 0 ip address 10.2.2.2 255.255.255.0 interface TokenRing 0

no ip address

ring-speed 16 source-bridge 2 1111 source-bridge spanning

Router B

dlsw local-peer peer-id 10.1.1.1 dlsw remote-peer 0 tcp 10.2.2.2 interface loopback 0 ip address 10.1.1.1 255.255.255.0 interface serial 0

mtu 4096

no ip address

encapsulation sdlc

no keepalive

nzri-encoding

clockrate 9600

sdlc vmac 4000.3745.0000

sdlc N1 48016

sdlc address 04 echo

sdlc partner 4000.1111.0020 04

sdlc dlsw 4

Configuring Data-Link Switching Plus

DLSw+ Translation Between Ethernet and Token Ring Configuration Example

DLSw+ also supports Ethernet media. The configuration is similar to other DLSw+ configurations, except for configuring for a specific media. The following example shows Ethernet media (see

Figure 135).

Figure 135 DLSw+ Translation Between Ethernet and Token Ring

Router A

128.207.111.1

Router A

hostname Router A ! dlsw local-peer peer-id 128.207.111.1 dlsw remote-peer 0 tcp 128.207.1.145

Router B

e1/2

128.207.1.145

Token

Ring

AS/400

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H6565

dlsw bridge-group 5 ! interface loopback 0 ip address 128.207.111.1 255.255.255.0 interface Ethernet 0 no ip address

bridge-group 5 ! bridge 5 protocol ieee

Router B

hostname Router B ! source-bridge transparent 500 1000 1 5 dlsw local-peer peer-id 128.207.1.145 dlsw remote-peer 0 tcp 128.207.111.1 dlsw bridge-group 5 ! interface loopback 0 ip address 128.207.1.145 255.255.255.0 interface ethernet 1/2 no ip address

bridge-group 5 ! interface tokenring 2/0

no ip address

ring-speed 16

source-bridge 7 1 500

source-bridge spanning ! bridge 5 protocol ieee

DLSw+ Configuration Examples

Because DLSw+ does not do local translation between different LAN types, Router B must be configured for SR/TLB by issuing the source-bridge transparent command. Also, note that the bridge groups are configured on the ethernet interfaces.

DLSw+ Translation Between FDDI and Token Ring Configuration Example

DLSw+ also supports FDDI media. The configuration is similar to other DLSw+ configurations except for configuring for a specific media type. The following example shows FDDI media (see Figure 136).

Figure 136 DLSw+ Translation Between FDDI and Token Ring

FDDI

DLSw+

Router A Router B

In the following configuration, an FDDI ring on Router A is connected to a Token Ring on Router B across a DLSw+ link.

Router A

source-bridge ring-group 10 dlsw local-peer peer-id 132.11.11.2 dlsw remote-peer 0 tcp 132.11.11.3 interface loopback 0 ip address 132.11.11.2 255.255.255.0

Token

Ring

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1000.5aed.1F53

DLSw+ Configuration Examples

interface fddi 0

no ip address source-bridge 26 1 10 source-bridge spanning

Router B

source-bridge ring-group 10 dlsw local peer peer-id 132.11.11.3 dlsw remote-peer 0 tcp 132.11.11.2 interface loopback 0 ip address 132.11.11.3 255.255.255.0 interface tokenring 0

no ip address source-bridge 25 1 10 source-bridge spanning

DLSw+ Translation Between SDLC and Token Ring Media Example

DLSw+ provides media conversion between local or remote LANs and SDLC. For additional information about configuring SDLC parameters, refer to the chapter “Configuring LLC2 and SDLC Parameters.”

Figure 137 illustrates DLSw+ with SDLC encapsulation. For this example, 4000.1020.1000 is the MAC

address of the FEP host (PU 4.0). The MAC address of the AS/400 host is 1000.5aed.1f53, which is defined as Node Type 2.1. Router B serves as the primary station for the remote secondary station 01. Router B can serve as either primary station or secondary station to remote station D2.

Figure 137 DLSw+ Translation Between SDLC and Token Ring Media

AS/400

Router B

S2 S1

PU type 2.0

sdlc address

Token

Ring

400

Token

Ring

100

51863

FEP

4000.1020.1000

Token

Ring

500

Router A

PU type 2.1

sdlc address

Router A

hostname Router A ! source-bridge ring-group 2000 dlsw local-peer peer-id 150.150.10.2 dlsw remote-peer 0 tcp 150.150.10.1

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! interface loopback 0 ip address 150.150.10.2 255.255.255.0 interface serial 8

ip address 150.150.11.2 255.255.255.192

clockrate 56000

! interface tokenring 0

no ip address

ring-speed 16

source-bridge 500 1 2000

source-bridge spanning ! router eigrp 202

network 150.150.0.0

Router B

hostname Router B ! source-bridge ring-group 2000 dlsw local-peer peer-id 150.150.10.1 dlsw remote-peer 0 tcp 150.150.10.2 ! interface loopback 0 ip address 150.150.10.1 255.255.255.0 interface serial 0

ip address 150.150.11.1 255.255.255.192 ! interface serial 1

description PU2 with SDLC station role set to secondary

no ip address

encapsulation sdlc

no keepalive

clockrate 9600

sdlc role primary

sdlc vmac 4000.9999.0100

sdlc address 01

sdlc xid 01 05d20006

sdlc partner 4000.1020.1000 01

sdlc dlsw 1 ! interface serial 2

description Node Type 2.1 with SDLC station role set to negotiable or primary

encapsulation sdlc

sdlc role prim-xid-poll

sdlc vmac 1234.3174.0000

sdlc address d2

sdlc partner 1000.5aed.1f53 d2

sdlc dlsw d2

DLSw+ Configuration Examples

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! interface tokenring 0

no ip address

ring-speed 16

source-bridge 100 1 2000

source-bridge spanning ! interface tokenring 1

no ip address

ring-speed 16

source-bridge 400 1 2000

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source-bridge spanning ! router eigrp 202

network 150.150.0.0

DLSw+ over Frame Relay Configuration Example

Frame Relay support extends the DLSw+ capabilities to include Frame Relay in direct mode. Frame Relay support includes permanent virtua l circuit c apability. DLSw+ runs over Frame Relay with or without local acknowledgement. It supports the Token Ring-to-Token Ring connections similar to FST and other direct data link controls. Figure 138 illustrates a DLSw+ configuration over Frame Relay with RIF Passthrough.

Figure 138 DLSw+ over Frame Relay

Configuring Data-Link Switching Plus

End station End statio

Token

Ring

Router A Router B

Frame Relay

Network

Frame Relay

Session

Direct Session

Token

Ring

The following configuration examples are based on Figure 139. The Token Rings in the illustration are in Ring 2.

Router A

source-bridge ring-group 100 dlsw local-peer 10.2.23.1 dlsw remote-peer 0 frame-relay interface serial 0 30 passthru interface loopback 0 ip address 10.2.23.1 255.255.255.0

interface tokenring 0

ring-speed 16

source-bridge spanning 1 1 100 ! interface serial 0

mtu 3000

no ip address

encapsulation frame-relay

frame-relay lmi-type ansi

frame-relay map dlsw 30

BC-324

Router B

source-bridge ring-group 100 dlsw local-peer 10.2.23.2 dlsw remote-peer 0 frame-relay interface serial 0 30 passthru interface loopback 0 ip address 10.2.23.2 255.255.255.0

interface tokenring 0

ring-speed 16

source-bridge spanning 2 1 100 !

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interface serial 0

mtu 3000 no ip address encapsulation frame-relay frame-relay lmi-type ansi frame-relay map dlsw 30

DLSw+ over QLLC Configuration Examples

The following three examples describe QLLC support for DLSw+.

Example 1

In this configuration, DLSw+ is used to allow remote devices to connect to a DLSw+ network over an X.25 public packet-switched network.

In this example, all QLLC traff ic is addressed to destination addr ess 4000.1161.1234, which is the MA C address of the FEP.

The remote X.25-attached IBM 3174 cluster controller is given a virtual MAC address of

1000.0000.0001. This virtual MAC address is mapped to the X.121 address of the 3174 (31104150101) in the X.25 attached router.

interface serial 0

encapsulation x25 x25 address 3110212011 x25 map qllc 1000.0000.0001 31104150101 qllc dlsw partner 4000.1611.1234

DLSw+ Configuration Examples

Example 2

In this configuration, a single IBM 3174 cluster controller needs to communicate with both an AS/400 and a FEP. The FEP is associated with subaddress 150101 and the AS/400 is associated with subaddress

151102. If an X.25 call comes in for 33204150101, the call is mapped to th e FEP and fo rwarded to MAC address

4000.1161.1234. The IBM 3174 appears to the FEP as a Token Ring-attached resource with MAC address 1000.0000.0001. The IBM 3174 uses a source SAP of 04 when communicating with the FEP, and a source SAP of 08 when communicating with the AS/400.

interface serial 0

encapsulation x25 x25 address 31102 x25 map qllc 1000.0000.0001 33204 qllc dlsw subaddress 150101 partner 4000.1161.1234 qllc dlsw subaddress 150102 partner 4000.2034.5678 sap 04 08

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Example 3

In this example, two different X.25 resources want to communicate over X.25 to the same FEP. In the router attached to the X.25 network, every X.25 connection request for X.121 address

31102150101 is directed to DLSw+. The first SVC to be established will be mapped to virtual MAC address 1000.0000.0001. The second SVC to be established will be mapped to virtual MAC address

1000.0000.0002.

interface serial 0

encapsulation x25

x25 address 31102

x25 map qllc 33204

x25 map qllc 35765

qllc dlsw subaddress 150101 vmacaddr 1000.0000.0001 2 partner 4000.1611.1234

DLSw+ with RIF Passthrough Configuration Example

Figure 139 is a sample configuration for DLSw+ us ing the RIF Passthrough feature.

Figure 139 Network Configuration with RIF Passthrough

Configuring Data-Link Switching Plus

3745

VR 100

A 10.1.12.1

TCP/IP

100

B 10.1.14.2

Router A

source-bridge ring-group 100 dlsw local-peer peer id 10.1.12.1 dlsw remote-peer 0 tcp 10.1.14.2 rif-passthru 100 interface loopback 0 ip address 10.1.12.1 255.255.255.0

interface tokenring 0

ring-speed 16 source-bridge 25 1 100 source-bridge spanning

Router B

source-bridge ring-group 100 dlsw local-peer peer id 10.1.14.2 dlsw remote-peer 0 tcp 10.1.12.1 rif-passthru 100 interface loopback 0 ip address 10.1.14.2 255.255.255.0

3745

10633

BC-326

interface tokenring 0

ring-speed 16 source-bridge 51 1 100 source-bridge spanning

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DLSw+ Configuration Examples

DLSw+ with Enhanced Load Balancing Configuration Example

Figure 140 shows DLSw+ with the Enha nced Load B alancing fe ature.

Figure 140 DLSw+ with Enhanced Load Balancing

Token

Ring

RTR B

Token

Ring

RTR A

RTR C

RTR D

Token

Ring

51972

Router A is configured for the DLSw+ Enhanced Load Balancing feature to load balance traffic among the DLSw+ remote peers B, C, and D .

Router A

dlsw local-peer 10.2.19.1 dlsw remote-peer 0 tcp 10.2 24.2 circuit-weight 10 dlsw remote-peer 0 tcp 10.2.19.5 circuit-weight 6 dlsw remote-peer 0 tcp 10.2.20.1 circuit-weight 20 dlsw load-balance circuit-count dlsw timer explorer-wait-time 100

Router B

dlsw local-peer 10.2.24.2 cost 1 promiscuous

Router C

dlsw local-peer 10.2.19.5 cost 1 promiscuous

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Router D

dlsw local-peer 10.2.20.1 cost 1 promiscuous

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DLSw+ Configuration Examples

Peer group 1 Peer group 2

DLSw+ Peer Cluster Feature Configuration Example

Figure 141 shows a DLSw+ network configured with the DLSw+ Peer Clusters feature.

Figure 141 DLSw+ Peer Cluster Feature

Peer cluster

ID 5

Configuring Data-Link Switching Plus

BP1

MPA

BP2

Token

Ring

MPB

17268

Because BP2 is configured as the border peer with the DLSw+ Peer Clusters feature, it does not forward explorers to both MPA and MPB since they are part of the same peer cluster.

BP2

source-bridge ring-group 310 dlsw local-peer 10.1.1.3 border group 2 promiscuous

MPA

source-bridge ring-group 310 dlsw local-peer 10.1.1.1 group 2 promiscuous cluster 5 dlsw remote-peer 0 tcp 10.1.1.3

MPB

source-bridge ring-group 310 dlsw local-peer 10.1.1.2 group 2 promiscuous cluster 5 dlsw remote-peer tcp 0 10.1.1.3

MPC

dlsw local-peer 10.1.1.4 group 2 promiscuous dlsw remote-peer tcp 0 10.1.1.3

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Workstation 3

Workstation 4

51973

DLSw+ Configuration Examples

DLSW+ RSVP Bandwidth Reservation Feature Configuration Example

Figure 142 shows a DLSw+ network with the DLSw+ RSVP Bandwidth Reservation feature conf igured.

Figure 142 DLSw+ RSVP Bandwidth Reservation Feature Con fig ured

Token

Ring

orkstation 1

DLSW RTR 1

10.2.17.1

DLSWRTR 1 and DLSWRTR 2 are configured for the DLSw+ RSVP Bandwidth Reservation feature with an average bit rate of 40 and a maximum-burst rate of 10.

DLSWRTR 1

dlsw local-peer peer id 10.2.17.1 dlsw remote-peer 0 tcp 10.2.24.3 dlsw rsvp 40 10

DLSWRTR2

dlsw local-peer peer id 10.2.24.3 dlsw remote-peer 0 tcp 10.2.17.1 dlsw rsvp 40 10

IP RTR 1 IP RTR 2 DLSW RTR 2

10.1.15.2

10.1.16.2

10.2.24.3

Workstation

The following output of the show ip rsvp sender command on the DLSWRTR2 verifies that PATH messages are being sent from DLSWRTR2:

DLSWRTR2#show ip rsvp sender To From Pro DPort Sport Prev Hop I/F BPS Bytes

10.2.17.1 10.2.24.3 TCP 2065 11003 10K 28K

10.2.24.3 10.2.17.1 TCP 11003 2065 10.2.17.1 Et1/1 10K 28K

The following output of the show ip rsvp req command on the DLSWRTR2 verifies that RESV messages are being sent from DLSWRTR2:

DLSWRTR2#show ip rsvp req To From Pro DPort Sport Next Hop I/F Fi Serv BPS Bytes

10.2.24.3 10.2.17.1 TCP 11003 2065 10.2.17.1 Et1/1 FF RATE 10K 28K

If the IP cloud is able to guarantee the bandwidth requested and the show ip rsvp sender and show ip rsvp req commands are successful, issue the show ip rsvp res command to verify that a reservation was

made from DLSWRTR1 to DLSWRTR2:

DLSWRTR2#show ip rsvp rese To From Pro DPort Sport Next Hop I/F Fi Serv BPS Bytes

10.2.17.1 10.2.24.3 TCP 2065 11003 10.2.17.1 Et1/1 FF RATE 10K 28K

10.2.24.3 10.2.17.1 TCP 11003 2065 FF RATE 10K 28K

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51974

Group 1 Group 2

DLSw+ Configuration Examples

DLSw+ RSVP Bandwidth Reservation Feature with Border Peers Configuration Example

Figure 143 shows a DLSw+ border peer network configured with DLSw+ RSVP.

Figure 143 DLSw+ RSVP Bandwidth Reservation Feature in a Border Peer Network

DLSW RTR 1

Token

Ring

10.2.17.1

Workstation 1

IP RTR 1 IP RTR 2 DLSW RTR 2

10.3.15.2

10.3.16.2

10.14.25.2

Token

Ring

Workstation 2

The following example conf ig ures DLSWRTR1 to send PATH messages at rates of 40 kbps and 10 kbps and DLSWRTR2 to send PATH messages at rates of 10.

DLSWRTR1

dlsw local-peer peer-id 10.2.17.1 group 1 promiscuous dlsw rsvp default dlsw remote-peer 0 tcp 10.3.15.2 dlsw peer-on-demand-defaults rsvp 40 10

IPRTR1

dlsw local-peer peer-id 10.3.15.2 group 1 border promiscuous dlsw remote-peer 0 tcp 10.3.16.2

BC-330

IPRTR2

dlsw local-peer peer-id 10.3.16.2 group 2 border promiscuous dlsw remote-peer 0 tcp 10.3.15.2

DLSWRTR2

dlsw local-peer peer-id 10.14.25.2 group 2 promiscuous dlsw rsvp default dlsw remote-peer 0 tcp 10.3.16.2

The following output of the sho w ip rsvp sender command on DLSWR TR2 verifies t hat P ATH messages are being sent from DLSWRTR2:

DLSWRT2#show ip rsvp sender To From Pro DPort Sport Prev Hop I/F BPS Bytes

10.2.17.1 10.14.25.2 TCP 2065 11003 10K 28K

10.14.25.2 10.2.17.1 TCP 11003 2065 10.2.17.1 Et1/1 10K 28K

The following output of the show ip rsvp request command on DLSWRTR2 verifies that RESV messages are being sent from DLSWRTR 2:

DLSWRT2#show ip rsvp req To From Pro DPort Sport Next Hop I/F Fi Serv BPS Bytes

10.14.25.2 10.2.17.1 TCP 11003 2065 10.2.17.1 Et1/1 FF RATE 10K 28K

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Router D

The following output of the show ip rsvp res command on the DLSWRTR1 verifies that the RSVP reservation was successful:

DLSWRTR1#show ip rsvp rese To From Pro DPort Sport Next Hop I/F Fi Serv BPS Bytes

10.2.17.1 10.14.25.2 TCP 2065 11003 10.14.25.2 Et1/1 FF RATE 10K 28K

10.14.25.2 10.2.17.1 TCP 11003 2065 FF RATE 10K 28K

DLSw+ with Ethernet Redundancy Configuration Example

Figure 144 shows that Router A, Router B, and Router C advertise their presence on the Ethernet via

their Ethernet interfaces to the multicast MA C address 999 9.9999.999 9. Because Router B is the master router, it keeps a database of all circuits handled within the domain and grants or denies permission for new circuit requests for Router A and Router C. There is no special configuration required for the end stations or for the remote peer. Only the DLSw+ devices on the LAN need the extra configuration. Master Router B waits 1.5 seconds after it receives the first IWANTIT primitive before assigning t he new SNA circuit to one of its ethernet redundancy peers because of the dlsw transparent timers sna 1500 command.

DLSw+ Configuration Examples

Figure 144 DLSw+ with Ethernet Redundancy

Workstation X

outer A

Router B Router C

Router A

dlsw local-peer peer id 10.2.24.2 dlsw remote-peer 0 tcp 10.2.17.1 interface loopback 0 ip address 10.2.24.2 255.255.255.0

17955

int e1

ip address 150.150.2.1 255.255.255.0 dlsw transparent redundancy-enable 9999.9999.9999

Router B

dlsw local-peer peer-id 10.2.24.3

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DLSw+ Configuration Examples

17956

dlsw remote-peer 0 tcp 10.1.17.1 interface loopback 0 ip address 10.2.24.3 255.255.255.0

int e1

ip address 150.150.2.2 255.255.255.0

dlsw transparent redundancy-enable 9999.9999.9999 master priority 1

dlsw transparent timers sna 1500

Router C

dlsw local-peer peer-id 10.2.24.4 dlsw remote-peer 0 tcp 10.2.17.1 interface loopback 0 ip address 10.2.24.4 255.255.255.0

int e1

ip address 150.150.2.3 255.255.255.0

dlsw transparent redundancy-enable 9999.9999.9999

Router D

dlsw local-peer peer-id 10.2.17.1 promiscuous

Configuring Data-Link Switching Plus

DLSw+ with Ethernet Redundancy Enabled for Switch Support Configuration Example

Figure 145 is a sample configuration of the DLSw+ Ethernet Redundancy feature in a switched

environmen t. The ethernet switch sees the device with MAC address 4000.0010.0001 one port at a time because Router A and Router B have mapped dif ferent MA C addresses to it. This conf iguration is kno wn as MAC-address mapping. Router A is configured so that MAC address 4000.0001.0000 maps to the actual device with MAC address 4000.0010.0001. Router B is configured so that MAC address

4000.0201.0001 maps to the actual device with MAC address 4000.0010.0001. Router A and B backup one another. Router A is configured as the master with a default priority of 100. Master Router A waits

1.5 seconds after it receives the f irst IWANTIT primitive before assigning the new SN A circuit to one of its ethernet redundancy peers because of the dlsw transparent timers sna 1500 command.

Figure 145 DLSw+ with Ethernet Redundancy in a Switched Environment

Workstation

orkstation X

Router A

4000.0010.0001

orkstation Y

BC-332

Cisco IOS Bridging and IBM Networking Configuration Guide

Ethernet switch

Router B

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Router A

dlsw local peer peer-id 10.2.17.1 dlsw remote-peer 0 tcp 10.3.2.1 dlsw transparent switch-support interface loopback 0 ip address 10.2.17.1 255.255.255.0

int e 0

mac-address 4000.0000.0001 ip address 150.150.2.1 255.255.255.0 dlsw transparent redundancy-enable 9999.9999.9999 master-priority dlsw transparent map local-mac 4000.0001.0000 remote-mac 4000.0010.0001 neighbor 4000.0000.0011 dlsw transparent timers sna 1500

Router B

dlsw local peer peer-id 10.2.17.2 dlsw remote-peer 0 tcp 10.3.2.1 dlsw transport switch-support interface loopback 0 ip address 10.2.17.2 255.255.255.0

int e 1 mac-address 4000.0000.0011 ip address 150.150.3.1 255.255.255.0 dlsw transparent redundancy-enable 9999.9999.9999 dlsw transparent map local-mac 4000.0201.0001 remote-mac 4000.0010.0001 neighbor 4000.0000.0001

DLSw+ Configuration Examples

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DLSw+ Configuration Examples

Configuring Data-Link Switching Plus

BC-334

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Cisco Systems BC-281 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

Technology Overview

DLSw Standard

DLSw Version 2 Standard

IP Multicast

UDP Unicast

Enhanced Peer-on-Demand Routing Feature

Expedited TCP Connection

DLSw+ Features

Local Acknowledgment

Notes on Using LLC2 Local Acknowledgment

DLSw+ Support for Other SNA Features

DLSw+ Configuration Task List

Defining a DLSw+ Local Peer for the Router

Defining a DLSw+ Remote Peer

TCP Encapsulation

TCP/IP with RIF Passthrough Encapsulation

FST Encapsulation

Direct Encapsulation

DLSw Lite Encapsulation

Mapping DLSw+ to a Local Data-Link Control

Token Ring

Ethernet

SDLC

QLLC

FDDI

Configuring Advanced Features

Scalability

Availability

Modes of Operation

Network Management

Traffic Bandwidth and Queueing Management

Access Control

Verifying DLSw+

Configuring DLSw+ Timers

Monitoring and Maintaining the DLSw+ Network

DLSw+ Configuration Examples

DLSw+ with SDLC Multidrop Support Configuration Examples

DLSw+ with LLC2-to-SDLC Conversion Between PU 4-to-PU 4 Communication Example

DLSw+ Translation Between Ethernet and Token Ring Configuration Example

DLSw+ Translation Between FDDI and Token Ring Configuration Example

DLSw+ Translation Between SDLC and Token Ring Media Example

DLSw+ over Frame Relay Configuration Example

DLSw+ over QLLC Configuration Examples

DLSw+ with RIF Passthrough Configuration Example

DLSw+ with Enhanced Load Balancing Configuration Example

DLSw+ Peer Cluster Feature Configuration Example

DLSW+ RSVP Bandwidth Reservation Feature Configuration Example

DLSw+ RSVP Bandwidth Reservation Feature with Border Peers Configuration Example

DLSw+ with Ethernet Redundancy Configuration Example

DLSw+ with Ethernet Redundancy Enabled for Switch Support Configuration Example