Cabletron Systems DMS-100 User Manual

DMS-100 Family

Ethernet Interface Unit

User Guide

TELECOM12 Standard 03.01 August 1999

297-8991-910

DMS-100 Family

Ethernet Interface Unit

User Guide

Document number: 297-8991-910
Product release: TELECOM12
Document release: Standard 03.01
Date: August 1999

© 1998 Northern Telecom
All rights reserved
Printed in the United States of America

NORTHERN TELECOM CONFIDENTIAL: The information contained in this document is the property of

Northern Telecom. Except as specifically authorized in writing by Northern Telecom, the holder of this document shall keep the
information contained herein confidential and shall protect same in whole or in part from disclosure and dissemination to third
parties and use same for evaluation, operation, and maintenance purposes only.

Information is subject to change without notice.

DataSPAN, DMS, DMS-100, DMS-100/200, DMS-200, MAP, Meridian, Nortel, SuperNode, and SuperNode Data Manager are
trademarks of Northern Telecom. Ethernet is a trademark of Xerox Corporation. MacIntosh is a trademark of Apple Corp. Sun is a
trademark of Sun Microsystems. HP is a trademark of Hewlett-Packard Ltd.

iv

297-8991-910 Standard 03.01 August 1999

Publication history

August 1999

TELECOM12 Standard 03.01 Updated Chapter 2 and Appendix C in response
to Feature 59010371, FTP Extended Functionality.

May 1999

TELECOM09 Standard 02.02 Implemented design comments.

March 1999

TL09 Standard 02.01 Updated table IPNETWRK with correct datafill.
Implemented design review comments.

TL08 Standard 02.01 References to file transport access manager (FTAM)
deleted.

TL07

February 1998

TL07 Standard 01.01 First standard release of this document.

v

DMS-100 Family EIU User Guide TELECOM12

vi Publication history

297-8991-910 Standard 03.01 August 1999

Contents

About this document xv

When to use this document xv
How to check the version and issue of this document xv
References in this document xv

What precautionary messages mean xvii
How commands, parameters, and responses are represented xviii

Chapter 1: Introduction to the EIU 21

Overview of the EIU 22
System architecture 23

Hardware description 28

Capabilities, limitations, and restrictions 33

Feature packaging 38
EIU provisioning requirements 39

Billing 42
Service orders 42
User interface characteristics 42
Logs, alarms, and OMs 43

vii

Internet request for comment documents xvi

Input prompt (>) xviii
Commands and fixed parameters xix
Variables xix
Responses xix

DMS-bus interface and expansion 24
Inter-message switch links required with LPP 25
Data communications interface architecture 25

Ethernet interface card (NT9X84) 31
Ethernet physical interfaces 32
Grounding requirements 33

EIU hardware capabilities and limitations 34
System-wide limitations 36
Limitations associated with maintenance 36
Limitations associated with protocols 37

DMS-bus inter-MS provisioning 39
DMS-bus external MS provisioning 40
EIU provisioning 41
EIU sparing and redundancy 41

Log reports 43
Alarms 43

DMS-100 Family EIU User Guide TELECOM12

viii Contents

Operational measurements 43

Chapter 2: EIU messaging protocols 45

Software architecture 46

Supported protocols 49
Addressing 54

Protocol engineering 61

IP throttling 61
TCP connection management 61
FTP session control 63
Protocol buffer engineering 63

IP throttling 65

IP throttling for LPP 65
IP throttling for SSLPP 66

Chapter 3: EIU datafill 67

Interdependency and auto-configuration 68
Table LIUINV 68

Datafill sequence and implications 69
Table LIUINV datafill 69
EIU MAC addresses 72
IP addresses 73
Sample datafill for table LIUINV 73

Table IPNETWRK 73

Datafill sequence and implications 74
Datafill for table IPNETWRK 74
Sample datafill for table IPNETWRK 77
Supplementary information 78

Table IPROUTER 78

Datafill sequence and implications 79
Datafill 79
Sample datafill for table IPROUTER 80

Table IPHOST 80

Datafill sequence and implications 81
Datafill 81
Sample datafill for table IPHOST 89

Table IPTHRON 89

Datafill sequence and implications 91
Datafill 91
Sample datafill for table IPTHRON 93

Table IPPROTO 93

Datafill sequence and implications 94
Datafill 94
Sample datafill for table IPPROTO 94

Table ENSITES 95

Datafill sequence and implications 95
Datafill 95
Sample datafill for table ENSITES 95

Table ENTYPES 95

Datafill sequence and implications 95

297-8991-910 Standard 03.01 August 1999

Contents ix

Datafill 95
Sample datafill for table ENTYPES 96

Table EXNDINV 96

Datafill sequence and implications 97
Datafill 98
Sample datafill for table EXNDINV 102

Chapter 4: EIU maintenance 103

EIU MAP level 104

Manual busy state 104
In-service state 104

EIU diagnostics 104

Out-of-service diagnostics 104
In-service diagnostics 105
In-service leaky bucket audit 105

EIU overload control 106
EIU sparing requirements 107
Automated system maintenance 108
Manual system maintenance 109
Logs relevant to EIU OA&M 110
OMs relevant to EIU OA&M 110

Appendix A: EIU installation checklist 111
Appendix B: EIU troubleshooting 113

Tools 114
Troubleshooting checklist 114

Appendix C: Using FTP 117

What is FTP? 118

Automatic Record Length Detection 118

Volume listing 120

FTP cookbook 120

FTP on the DMS-100 switch 120

Obtaining the IP address of the SuperNode host 122
Tutorial: basic FTP operations 123
Tutorial: moving files 126
Tutorial: advanced operations 131
FTP operations reference 135

Appendix D: Using telnet 141

Telnet access to a switch 142

Appendix E: Understanding IP and IP addressing 145

What is internetworking? 145
What is routing? 146
Routing and routed protocols 146
Planning overview 147
Mapping the network 147
Choosing IP addresses 149

DMS-100 Family EIU User Guide TELECOM12

x Contents

IP addresses 150

Address masks 157

Network numbering example 158
Firewalls and network security 159
Variable-width subnetworks 160
Protocols related to Internet Protocol 160

Internet Protocol 160

Internet control message protocol 161

Transmission control protocol 161

User datagram protocol 161

Address resolution protocol 161

Reverse ARP 162

Proxy ARP 162

Inverse ARP 162

Bootstrap Protocol 162

File transfer protocol 163

Open shortest path first 163

Routing information protocol 163

Telnet 163

Appendix F: EIU supported configurations 165
Appendix G: IP network number requests 171

Overview 171
Considerations for obtaining IP addresses 171
NIC IP network number request form 172

Appendix H: ASU background information 177

Application-specific units and supported services 177

Link interface unit 177

Ethernet interface unit 177

Frame relay interface unit 178

X.25/X.75 link interface unit 178

Network interface unit 179

Voice processor unit and ADAS 179

ASUs and Cellular digital packet data 179

External routers 180
Platforms 180

Link peripheral processor 180

Single-shelf link peripheral processor 182

SuperNode SE link interface shelf 183

Appendix I: Obtaining a MAC address 185

Overview 185
MAC address format 185
How to get the MAC address for an EIU 187

List of terms 189

297-8991-910 Standard 03.01 August 1999

List of figures

Figure 1 Overall architecture of enhanced SuperNode system 24
Figure 2 Ethernet interface data flow 26
Figure 3 EIU mapping to lower levels of the OSI communications model 28
Figure 4 Link interface shelf, with 2-slot EIU locations 29
Figure 5 SSLPP, with 2-slot EIU locations 30
Figure 6 DMS SuperNode switch LPP with an EIU 30
Figure 7 DMS SuperNode FLIS with an EIU 31
Figure 8 Ethernet interface architecture 32
Figure 9 Example of DMS-bus intermessage switch configuration 40
Figure 10 MAP display level hierarchy 42
Figure 11 SuperNode TCP/ IP protocol stack 47
Figure 12 SuperNode TCP/IP message flow 48
Figure 13 Typical configuration for LAN and SuperNode subnets 56
Figure 14 An example SuperNode Ethernet 59
Figure 15 Datafill example for table LIUINV 73
Figure 16 Datafill examples for table IPNETWRK 77
Figure 17 Datafill example for table IPROUTER 80
Figure 18 Datafill example for table IPHOST 89
Figure 19 Datafill example for table IPTHRON 93
Figure 20 Datafill example for table IPPROTO 94
Figure 21 Datafill example for table ENSITES 95
Figure 22 Datafill example for table ENTYPES 96
Figure 23 Table EXNDINV filters IP packets 97
Figure 24 Datafill example for table EXNDINV 102
Figure 25 EIU redundant configuration 108
Figure 26 Simple network map 148
Figure 27 Detailed network diagram 149
Figure 28 IP address structure 150
Figure 29 IP addressing: class A 152
Figure 30 Subnet mask: class A 153
Figure 31 IP addressing: class B 154
Figure 32 Subnet mask: class B 155
Figure 33 IP addressing: class C 156

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DMS-100 Family EIU User Guide TELECOM12

xii

Figure 34 Subnet mask: class C 156
Figure 35 IP addressing: class D 157
Figure 36 IP addressing: class E 157
Figure 37 Address mask example 158
Figure 38 Simple network numbering 159
Figure 39 Host configuration 166
Figure 40 Router configurations 167
Figure 41 Host and router configuration 168
Figure 42 Interface configuration part 1 169
Figure 43 Interface Configuration part 2 170
Figure 44 LPP architecture 181
Figure 45 SSLPP architecture 183
Figure 46 SNSE-LIS architecture 184
Figure 47 EIU MAC address format 186

297-8991-910 Standard 03.01 August 1999

List of tables

Table 1 DMS-Core feature packages 38
Table 2 DMS-bus port engineering requirements for peripherals 41
Table 3 IP routing table 60
Table 4 IP route list table 60
Table 5 TCP connection limits by SuperNode subsystem 62
Table 6 UDP connection limits by SuperNode subsystem 62
Table 7 Buffer allocation per end point 64
Table 8 IP throttling values for LPP 65
Table 9 IP throttling values for SSLPP 66
Table 10 Summary of data schema tables required for EIU provisioning 67
Table 11 Field descriptions for table LIUINV for EIU datafill 69
Table 12 Field descriptions for table IPNETWRK for EIU datafill 75
Table 13 Field descriptions for table IPROUTER for EIU datafill 79
Table 14 Field descriptions for table IPHOST for EIU datafill 81
Table 15 Field descriptions for conditional datafill for NODENAME = AP 83
Table 16 Field descriptions for conditional datafill for NODENAME = APU 84
Table 17 Field descriptions for conditional data for NODENAME = CM 85
Table 18 Field descriptions for conditional datafill for NODENAME = EIU 86
Table 19 Field descriptions for conditional datafill for NODENAME = ELIU 87
Table 20 Field descriptions for conditional datafill for NODENAME = FP 88
Table 21 Field descriptions for conditional datafill for NODENAME = MS 89
Table 22 Field descriptions for table IPTHRON for EIU datafill 91
Table 23 Field descriptions for table IPPROTO for EIU datafill 94
Table 24 Field descriptions for table ENSITES for EIU datafill 95
Table 25 Field descriptions for table ENTYPE for EIU datafill 96
Table 26 Field descriptions for table EXNDINV for EIU datafill 98
Table 27 EIU LAN fault leaky bucket parameters 106
Table 28 EIU installation checklist 112
Table 29 Tools for EIU troubleshooting 114
Table 30 EIU troubleshooting checklist 114
Table 31 Examples of filenames with record length in their extension 119
Table 32 Examples of filenames without record length in their extension 119
Table 33 FTP commands on the DMS-100 switch 121

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DMS-100 Family EIU User Guide TELECOM12

xiv

Table 34 FTP operations reference: workstation to DMS 136
Table 35 FTP operations reference: DMS to workstation 138
Table 36 IP address classes 150
Table 37 NIC IP address request form 172

297-8991-910 Standard 03.01 August 1999

About this document

This document is a source of information for the Ethernet interface unit (EIU)
product. The document provides the following information:

• hardware description

• protocol descriptions

• datafill requirements

• maintenance

• background information supporting the main chapters

When to use this document

Use this document for understanding the installation of the EIU, and for
operating and maintaining the EIU.

How to check the version and issue of this document

The version and issue of the document are indicated by numbers, for example,

01.01.

xv

The first two digits indicate the version. The version number increases each
time the document is updated to support a new software release. For example,
the first release of a document is 01.01. In the next software release cycle, the
first release of the same document is 02.01.

The second two digits indicate the issue. The issue number increases each time
the document is revised but rereleased in the same software release cycle. For
example, the second release of a document in the same software release cycle
is 01.02.

To determine which version of this document applies to the software in your
office and how documentation for your product is organized, consult the
release information in “Publication history” on page v of this document.

References in this document

The following documents can be consulted for additional information or are
referred to in this document:

DMS-100 Family EIU User Guide TELECOM12

xvi

• Commands Reference Manual, 297-1001-822

• DMS SuperNode DataSPAN Frame Relay Service Maintenance Guide,
297-5111-501

• DMS SuperNode SCP II Maintenance Guide, 297-5131-541

• Link Interface Unit (LIU7) Memory Calculation, System Engineering
Bulletin SEB 92-01-001

• Link Interface Unit (LIU7) Memory Calculation for an End Office, System
Engineering Bulletin SEB 92-03-004

• Link Interface Unit (LIU7) Memory Calculation for an Integrated Node,
System Engineering Bulletin SEB 92-03-005

• LPP/ELPP/LIU7/DLIU Performance, Throughput, and Capacity, System
Engineering Bulletin SEB 92-12-001

• DMS-100 Alarm Clearing and Performance Monitoring Procedures,
297-xxxx-543

• DMS-100 Card Replacement Procedures, 297-xxxx-547

• DMS-100 Log Reports Reference Manual, 297-xxxx-840

• DMS-100 Office Parameters Reference Manual,
297-xxxx-855

• DMS-100 Operational Measurements Reference Manual, 297-xxxx-814

• DMS-100 PM Software Release Document, 297-8981-599

• DMS-100 Recovery Procedures, 297-xxxx-545

• DMS-100 Routine Maintenance Procedures,
297-xxxx-546

• DMS-100 Translations Guide, 297-xxxx-350

• DMS-100 Trouble Locating Procedures, 297-xxxx-544

• Peripheral Modules Maintenance Guide, 297-xxxx-592

• Provisioning Rules for LPP, SSLPP, and SNSE LIS, System Engineering
Bulletin SEB 92-02-001

• SuperNode Data Manager Simplex User Guide, 297-5051-900

Internet request for comment documents

The following documents contain information related to Internet Protocol.
These documents are available from the Internet Network Information Center
servers.

• An Ethernet Address Resolution Protocol, RFC826

• Bootstrap Protocol, RFC951

297-8991-910 Standard 03.01 August 1999

• Clarifications and Extensions for the Bootstrap Protocol, RFC1542

• File Transfer Protocol, RFC959

• Internet Control Message Protocol, RCF792

• Internet Protocol, RFC791

• OSPF Version 2, RFC1583

• Reverse Address Resolution Protocol, RFC903

• Routing Information Protocol, RFC1058

• Telnet Protocol Specifications, RFC495

• Transmission Control Protocol, RFC793

• User Datagram Protocol, RFC768

• Using ARP to Implement Transparent Subnet Gateways, RFC1027

What precautionary messages mean

The types of precautionary messages used in Northern Telecom (Nortel)
documents include attention boxes and danger, warning, and caution
messages.

xvii

An attention box identifies information that is necessary for the proper
performance of a procedure or task or the correct interpretation of information
or data. Danger, warning, and caution messages indicate possible risks.

Examples of the precautionary messages follow.
ATTENTION Information needed to perform a task

ATTENTION

If the unused DS-3 ports are not deprovisioned before a DS-1/VT Mapper
is installed, the DS-1 traffic will not be carried through the DS-1/VT
Mapper, even though the DS-1/VT Mapper is properly provisioned.

CAUTION Possibility of service interruption or degradation

CAUTION
Possible loss of service

Before continuing, confirm that you are removing the card
from the inactive unit of the peripheral module. Subscriber
service will be lost if you remove a card from the active unit.

DMS-100 Family EIU User Guide TELECOM12

xviii

CAUTION Possibility of equipment damage

CAUTION
Damage to the backplane connector pins

Align the card before seating it, to avoid bending the
backplane connector pins. Use light thumb pressure to align
the card with the connectors. Next, use the levers on the card
to seat the card into the connectors

CAUTION Possibility of static electricity damage

CAUTION
Static electricity damage

Wear a static discharge wrist strap connected to the wrist­strap grounding point of a frame supervisory panel (FSP) or
a modular supervisory panel (MSP). This precaution protects
the cards against damage caused by static electricity.

DANGER Possibility of personal injury

DANGER
Risk of personal injury

Handle the card by the edges only. Do not touch the
components on the card. These components reach very high
temperatures, and can burn causing personal injury.

DANGER Possibility of electrocution

DANGER
Risk of electrocution

Do not open the front panel of the inverter unless fuses F1,
F2, and F3 have been removed. The inverter contains high
voltage lines. Until the fuses are removed, the high voltage
lines are active, and you risk being electrocuted.

How commands, parameters, and responses are represented

Commands, parameters, and responses in this document conform to the
following conventions.

Input prompt (>)

An input prompt (>) indicates that the information that follows is a command:

>BSY

297-8991-910 Standard 03.01 August 1999

Commands and fixed parameters

Commands and fixed parameters that are entered at a MAP terminal are shown
in uppercase letters:

>BSY CTRL ctrl_no

Variables

Variables are shown in lowercase letters:

>BSY CTRL ctrl_no

The letters or numbers that the variable represents must be entered. Each
variable is explained in a list that follows the command string.

Responses

Responses correspond to the MAP display and are shown in a different
typeface:

FP 3 Busy CTRL 0: Command request has been submitted.
FP 3 Busy CTRL 0: Command passed.

The following excerpt from a procedure shows the command syntax used in
this document:

xix

Step Action
1 Start the FTP tool by typing

>ftp nnn.nnn.nnn.nnn

and pressing the Enter key.

where

nnn is the portion of the IP address that identifies the node

Example:

>ftp 47.187.112.215

Example of a MAP response:

Allocated a Session ID Successfully 220 bcaryfc6 FTP
server
(Version $Revision: 1.21 $ $Date: 88/12/21 10:19:25 $) r

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297-8991-910 Standard 03.01 August 1999

Chapter 1: Introduction to the EIU

This chapter describes the Ethernet interface unit (EIU).

CAUTION
Possible loss of network security

Using the EIU and a telnet or file transfer protocol (FTP)
session to establish a maintenance and administration
position (MAP) session can introduce a security risk to both
the DMS node and its subtending network.

When establishing and operating a MAP session in this way,
there is limited security for clear text (user identification and
passwords) and for Internet Protocol (IP) addresses for
screening. This limited security makes an open local area
network (LAN) vulnerable to entry by unauthorized persons.

Nortel recommends that the operating company, as a
minimal precaution, integrate intermediate security servers
with encryption to avoid unauthorized access to the switch.
For alternative approaches, contact your Nortel
representative to discuss state-of-the-art secure OA&M data
communications equipment products.

21

By using the EIU, telnet, and FTP software, the operating
company assumes any and all risks associated with the
implementation and use of this hardware and software.

Topics in the chapter include the following:

• overview of the EIU

• system architecture

• hardware description

• limitations and restrictions

• feature packaging

DMS-100 Family EIU User Guide TELECOM12

22 Chapter 1: Introduction to the EIU

• EIU provisioning requirements

• billing

• service orders

• user interface characteristics

• logs, alarms, and operational measurements (OM)

Overview of the EIU

The EIU is an application-specific unit (ASU) that supports Ethernet
connectivity on the DMS-100 switch. You can configure the EIU as either an
IP router or an OSI router. The EIU also supports host services.

The EIU is intended primarily as a high-speed interface that provides
connectivity in a co-located environment such as that in a Central Office.
However, if the EIU is deployed in a LAN extending beyond the co-located
environment, you should observe the limitations and network security notes in
the caution above.

The following list summarizes the router and host services that use dedicated
EIUs. For general information on ASUs, refer to “Appendix G: ASU
background information”.

Note: The following applications may not be available in all product lines
or markets. For more information, consult with the specific Product Line
Manager or contact Nortel Networks.

• Automated directory assistance service (ADAS). ADAS provides
assistance to an operator by automatically prompting subscribers for
directory assistance information. ADAS uses the EIU to support
messaging between an ADAS OA&M position and the DMS-100 switch.

• Billing server. Billing server allows the DMS-100 switch to forward
billing and OM information from a DMS file processor (FP) to an external
operating company billing processor. The OM data is sent to the
downstream processor through a different EIU. The system throttles the
billing server traffic at 36 kbyte/sec. Note that this application is only
supported on DMS-250 or combinations with DMS-250 and GSM product
lines.

• Automatic file transfer (AFT). The AFT application lets the operating
company use TCP/IP to transport billing and operational measurement
(OM) data from the DMS-250 IOC (input/output controller) disks to the
downstream processor over an Ethernet LAN. One EIU can support both
billing and OMs. For this application, the recommended number of EIUs
is two: one EIU is dedicated to billing data and the other is to OMs.

AFT is also referred to as Madley AFT. Limited availability.

297-8991-910 Standard 03.01 August 1999

• Cellular digital packet data (CDPD). The CDPD service transports
datagrams between the mobile and private/public data networks.

• Programmable service node (PSN). PSN is a flexible platform that lets
operating companies rapidly deploy advanced services into their network.
Deployment is achieved through a service control unit (SCU). The SCU is
an external computing platform that controls the call processing on the
switch using a high-speed data link.

• Remote management system (RMS). RMS provides telnet and file
transfer protocol (FTP) functionality to the DMS-250 switch. Telnet is a
protocol for remote terminal access.

• Intelligent Call Manager (ICM). ICM provides the protocol support for
Computer Telephony Integration applications (for example, Symposium
Call Center Server, SSCS) in accessing the DMS via TCP/IP protocols.

System architecture

The data communications environment supports data links that are not tied to
the call processing network functions of the switch. These links do not use the
DMS network or line access capabilities. This characteristic is important when
supporting OAM links. These links must become functional in the early stages
of switch initialization and remain functional through all but catastrophic
failures, including call processing failures.

Chapter 1: Introduction to the EIU 23

The EIU is a gateway between the DMS-bus and an Ethernet that supports user
data links. The EIU is a concentration point between remote peripherals
(workstations, terminals, and routers) and the DMS-bus. The remote
peripherals are not terminated on the EIU, but on concentrators. These remote
peripherals allow the network engineers to connect alternate link levels and
asynchronous terminal equipment (MAP terminals, printers, and so on) to the
system. The Ethernet also provides a link between the DMS-100 switch and
the workstations used for processing.

Figure 1 shows an overview of the architecture of the enhanced SuperNode
system.

DMS-100 Family EIU User Guide TELECOM12

24 Chapter 1: Introduction to the EIU

Figure 1 Overall architecture of enhanced SuperNode system

SLM

DMS-core

DMS-bus

Network IOC

SOS UNIXSOS SOS

9-track tape

FP
(flexible
file system)

AP
(provisionable
computing)

Communications server
(flexible data
communications interface)

DMS-bus interface and expansion

T wo methods are used to interface processing engines to the DMS-bus. Direct
links between the processors and the DMS-bus is the primary method for
establishing this connection. A secondary method involves the LPP, which is
used to fan out the message switch (MS). By having two methods, the DMS­100 switch has the flexibility for provisioning software functions to processors
based on price, performance, and packaging criteria.

AP
(provisionable
computing)

Ethernet

X.25

EIU

Workstation

The LPP extends the MS fanout within a single cabinet. This fanout is
accomplished by using a second-level MS pair to provide switching, and by
extending the messaging capability through an extended messaging bus. These

297-8991-910 Standard 03.01 August 1999

Chapter 1: Introduction to the EIU 25

second-level message switches are referred to as local message switches
(LMS).

The frame transport bus (F-bus) is a 32-Mbit/s messaging bus that resembles
the MS in its protocol. The use of a narrower data path allows access to two
buses through a single backplane. This feature lets a single processor card
connect to both planes of the LMS and to survive faults on one plane. Links
interconnecting planes of the LMSs are provided to allow transparent message
rerouting in the case of single faults.

Note: Because the interconnecting F-bus is a wire bus, it is limited to a
single cabinet.

Inter-message switch links required with LPP

Inter-message switch links (IML) between the MS planes are also required to
improve robustness. For example, two peripherals (such as an applications
processor and an EIU) can lose communication with each other if they
message through different planes of the MS. In this scenario, assume that one
peripheral is messaging through plane 0 only because of a failure. If the second
peripheral loses its link to plane 0, the two peripherals cannot communicate
even though they can communicate to the DMS-core for maintenance
purposes.

For this reason, there is a pair of IMLs in integrated service node (ISN)
switches. These IMLs are DS512 links that operate at 1024 Kbit/s. Other
improvements to the MS hardware are also required to conform with the ISN
maintenance strategies.

Data communications interface architecture

The overall architecture of the data communications subsystem is based
partially on the premise that the processing and the access method for these
entities must be separate.

For this reason, application processors (AP) have the intelligence to drive the
link protocols. This arrangement allows freedom to change access methods
and allows flexibility in satisfying the processing requirements for each
protocol. The emphasis is on providing locally attached, nonswitched
connections primarily for OAM interfaces. An example of the overall data
flow for the data communications environment is shown in figure 2.

DMS-100 Family EIU User Guide TELECOM12

26 Chapter 1: Introduction to the EIU

Figure 2 Ethernet interface data flow

DMS-bus

Messaging path

User AP
(protocol
processing, for
example, termi­nal drivers)

Given the cost of the SuperNode cabinet infrastructure, providing the standard
hard connection interfaces in this mechanical environment is not possible. For
this reason, interfaces are placed outside the boundaries of these cabinets.
Engineering approaches to LANs also address a similar problem. In LANs, it
is not economic to provide all types of data interfaces at each node on the LAN.
The communications server provides a range of communications services to all
users on the LAN and may be located anywhere on the LAN.

Another major functional requirement that the EIU satisfies is providing
connectivity to commercially available workstations for value-added services.
This requirement is provided through a standard interconnect media. The
majority of these workstations support an Ethernet interface for local area
networking. The EIU also supports this protocol.

Data
communications
processor
(transport
interface)

Ethernet

LAN

Workstations

Communications
server

Data

Terminals

links

The EIU supports packet communication into a LAN. The standards for its
physical implementation are defined in IEEE 802.3. The EIU supports a
10 Mbit/s base band bus type of LAN for broadcast. The LAN uses a carrier
sense multiple access with collision detection (CSMA/CD) method for
arbitrating access to the communications channel.

Lastly, the EIU also provides a protocol gateway into the DMS-100
environment.

297-8991-910 Standard 03.01 August 1999

Chapter 1: Introduction to the EIU 27

The Ethernet interface takes advantage of commercially supported peripherals
and functions. These interface devices are selected and qualified for
applications in the DMS-100 switch, with particular attention to hardware
compliance, maintainability, and the protocol set provided. The following
devices are commercially available:

• LAN repeaters to locally extend the range of the LAN

• LAN gateways to extend the range of the LAN to a metropolitan-area
network (MAN) or a wide-area network (WAN)

• asynchronous terminals and printers through communications servers at up
to 19.2 Kbit/s

• synchronous data links through communications servers at up to 56 Kbit/s

• IBM mainframe access through channel interconnect units

• workstations (for example, Sun, HP, IBM), Macintoshs, and PCs

• servers

The EIU is a simplex engine. A simplex engine is sufficient for the EIU
because the facilities that are connected through the EIU are not critical to the
operation of the switch (that is, for call processing). Sets of EIUs may be used
with one or more EIUs available as a warm standby spare. The mapping of the
EIU architecture to the OSI reference model is shown in figure 3 on page 28.

For more information on EIU sparing, refer to “EIU sparing and redundancy”
on page 41.

DMS-100 Family EIU User Guide TELECOM12

28 Chapter 1: Introduction to the EIU

Figure 3 EIU mapping to lower levels of the OSI communications model

OSI reference model layers

Data link Layer

Physical Layer

Hardware description

The EIU is based on hardware originally developed for the signaling transfer
point (STP). One of the main components of the STP is the LPP, which is a
frame that can hold up to 36 two-slot ASUs. An LPP containing an EIU is
deployed in a DMS SuperNode switch to establish Ethernet connectivity.

Logical link control
Media access control
Physical signaling

Attachment
unit interface

Attachment
unit interface

Media access unit

Transmission medium

EIU partitioning

EIU software

Ethernet interface hardware

AUI PB

15-conductor
connectorized
cable

External
equipment

RG-58 coaxial
cable

UTP PB

4-wire twisted
pair, LAN hub

Figure 4 on page 29 shows where the EIU is provisionable on the link interface
shelf (LIS). Figure 5 on page 30 shows where the EIU is provisionable on the
single-shelf link peripheral processor (SSLPP).

The EIU consists of three cards provisioned in two slots, as shown in figure 4
and figure 5:

• NT9X84AA, Ethernet interface card (EIC). This processor board
implements most of the media access control (MAC) layer on a single chip.
It has 384 kbyte of high-speed buffer for holding Ethernet packets.

• NT9X85AA, Ethernet interface paddle board (EIP). This paddle board
provides the physical link to the local area network (LAN). The paddle
board implements an unshielded twisted-pair attachment unit interface
(AUI).

• NTEX22BA/BB, Integrated processor and F-bus card (IPF). This
processor board contains a Motorola M68020 processor and 8 Mbyte of

297-8991-910 Standard 03.01 August 1999

RAM. The NTEX22CA provides 32 Mbyte of RAM and higher
throughput performance.

NTEX22 also contains a peripheral bus (P-bus) to F-bus interface. The P­bus to F-bus interface connects the processor bus with the frame bus, which
in turn is connected to the local message switch (LMS) through the rate
adaptor.

The IPF card is a common processor card used by almost all ASUs and
runs the Support Operating System (SOS).

Figure 4 Link interface shelf, with 2-slot EIU locations

Top view of LIS shelf

Chapter 1: Introduction to the EIU 29

2-slot ASU

Rear paddle boards Front cards

2-slot EIU

NT9X84NT9X85 Ethernet AUI PB
NTEX22 Integrated processor and F-bus card

DMS-100 Family EIU User Guide TELECOM12

Ethernet interface card

30 Chapter 1: Introduction to the EIU

Figure 5 SSLPP, with 2-slot EIU locations

Top view of SSLPP shelf

2-slot ASU

Rear paddle boards Front cards

Ethernet interface card

2-slot EIU

NT9X84NT9X85 Ethernet AUI PB
NTEX22 Integrated processor and F-bus card

Figure 6 shows the placement of an LPP provisioned with an EIU on a DMS
SuperNode switch.

Figure 6 DMS SuperNode switch LPP with an EIU

LMS
plane 0

LMS
plane1

MS 0

MS 1

DS30 links

Figure 7 shows EIU links to the MS on the fiberized link interface shelf (FLIS).

F-bus 0

F-bus 1

EIU

EIU

Ethernet

EIU

297-8991-910 Standard 03.01 August 1999