3com CoreBuilder 5000 FastModule User Guide

CoreBuilder™5000

FastModule User Guide

http://www.3com.com

Document Number 17-00875-4 Published May 1997

3Com Corporation 5400 Bayfront Plaza Santa Clara, California 95052-8145

©3Com Corporation, 1997 (1996). All rights reserved. No part of this documentation may be reproduced in any form or by any means or used to make any derivative work (such as translation, transformation, or adaptation) without permission from 3Com Corporation. Portions of this product are based upon copyrighted materials of third parties.

3Com Corporation reserves the right to revise this documentation and to make changes in content from time to time without obligation on the part of 3Com Corporation to provide notification of such revision or change.

3Com Corporation provides this documentation without warranty of any kind, either implied or expressed, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose. 3Com may make improvements or changes in the products or programs described in this documentation at any time.

UNITED STATES GOVERNMENT LEGENDS:

If you are a United States government agency, then this documentation and the software described herein are provided to you subject to the following restricted rights:

For units of the Department of Defense:

Restricted Rights Legend: Use, duplication, or disclosure by the Government is subject to restrictions as set forth in subparagraph (c) (1) (ii) for Restricted Rights in Technical Data and Computer Software Clause at 48 C.F.R. 52.227-7013.

For civilian agencies:

Restricted Rights Legend: Use, reproduction, or disclosure is subject to restrictions set forth in subparagraph (a) through (d) of the Commercial Computer Software – Restricted Rights Clause at 48 C.F.R. 52.227-19 and the limitations set forth in the 3Com Corporation standard commercial agreement for the software. Unpublished rights reserved under the copyright laws of the United States.

If there is any software on removable media described in this documentation, it is furnished under a license agreement included with the product as a separate document, in the hardcopy documentation, or on the removable media in a directory file named LICENSE.TXT. If you are unable to locate a copy, contact 3Com and a copy will be sent to you.

Federal Communications Commission Notice

This equipment was tested and found to comply with the limits for a Class A digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference when the equipment is operated in a commercial environment. This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used in accordance with the instruction manual, may cause harmful interference to radio communications. Operation of this equipment in a residential area is likely to cause harmful interference, in which case you must correct the interference at your own expense.

Canadian Emissions Requirements

This Class A digital apparatus meets all requirements of the Canadian Interference-Causing Equipment Regulations.

Cet appareil numérique de la classe A respecte toutes les exigences du Règlement sur le matériel brouilleur du Canada.

EMC Directive Compliance

This equipment was tested and conforms to the Council Directive 89/336/EEC for electromagnetic compatibility. Conformity with this directive is based upon compliance with the following harmonized standards:

EN 55022 – Limits and Methods of Measurement of Radio Interference EN 50082-1 – Electromagnetic Compatibility Generic Immunity Standard: Residential, Commercial, and

Light Industry Warning: This is a Class A product. In a domestic environment, this product may cause radio interference, in

which case you may be required to take adequate measures. Compliance with this directive depends on the use of shielded cables.

Low Voltage Directive Compliance

This equipment was tested and conforms to the Council Directive 72/23/EEC for safety of electrical equipment. Conformity with this directive is based upon compliance with the following harmonized standard:

EN 60950 – Safety of Information Technology Equipment

VCCI Class 1 Compliance

This equipment is in the 1st Class category (information equipment to be used in commercial or industrial areas) and conforms to the standards set by the Voluntary Control Council for Interference by Information Technology Equipment aimed at preventing radio interference in commercial or industrial areas.

Consequently, when the equipment is used in a residential area or in an adjacent area, radio interference may be caused to radio and TV receivers, and so on.

Read the instructions for correct handling.

Fiber Cable Classification Notice

Use this equipment only with fiber cable classified by Underwriters Laboratories as to fire and smoke characteristics in accordance with Section 770-2(b) and Section 725-2(b) of the National Electrical Code.

UK General Approval Statement

The CoreBuilder 5000 Integrated System Hub and ONline System Concentrator are manufactured to the International Safety Standard EN 60950 and are approved in the U.K. under the General Approval Number NS/G/12345/J/100003 for indirect connection to the public telecommunication network.

Trademarks

Unless otherwise indicated, 3Com registered trademarks are registered in the United States and may or may not be registered in other countries.

3Com, LANsentry, Transcend, and TriChannel are registered trademarks of 3Com Corporation. CoreBuilder and 3TECH are trademarks of 3Com Corporation. 3ComFacts and Ask3Com are service marks of 3Com Corporation. The 3Com Multichannel Architecture Communications System is registered under U.S. Patent

Number 5,301,303. CompuServe is a registered trademark of CompuServe, Inc. VT100 and the Digital logo are trademarks of Digital Equipment Corporation. OpenView is a registered trademark of Hewlett-Packard Company. IBM is a registered trademark of International Business Machines, Incorporated. Microsoft and Windows are registered trademarks of Microsoft Corp. NETBIOS is a trademark of Micro Computer Systems, Inc. IPX is a trademark of Novell, Incorporated. Solaris, SunNet Manager, and SunOS are trademarks of Sun Microsystems, Inc. UNIX is a registered trademark in the United States and other countries, licensed exclusively through

X/Open Company, Ltd. Other brand and product names may be registered trademarks or trademarks of their respective holders.

iii

ABOUT THIS GUIDE

Audience 1 How to Use This Guide 1 Conventions 2 Related Documents 3

3Com Documents 3 Reference Documents 4

1 INTRODUCTION

FastModule Overview 1-2

WorkGroup Solutions 1-2

FastEthernet Solutions 1-2 FastModule Names 1-3 FastModule Features 1-3

Scalable Performance 1-4

Packet-Forwarding Modes 1-4

Outlet Port 1-5

Intelligent Flow Management 1-6

Full Duplex Support 1-6

Security 1-7

Resilient Links 1-7

Virtual LANs (VLANs) 1-7

PACE Technology 1-8

Spanning Tree Protocol 1-8

VLAN Server 1-8 Comparing FastModules to Bridges 1-9 FastModule Descriptions 1-9

24-Port FastModule 1-10

24-Port FastModule with FX Downlink 1-11

7-Port FX/TX FastModule 1-12

7-Port TX FastModule 1-13

Aggregator/Downlink FastModule 1-14 FastModule Backplane Connections 1-15

2 FASTMODULE MANAGEMENT OVERVIEW AND SETUP

FastModule Management Functions 2-2 Basic Management Tools 2-2

Using the FastModule Management Agent 2-2

Using the Distributed Management Module 2-2 Using Advanced Management Tools 2-3

Transcend Enterprise Manager for UNIX 2-3

Transcend Enterprise Manager for Windows 2-4

Third-Party SNMP-Based Tools 2-4 Setting Up Access for Basic Management 2-5

Setting Up FMA Access 2-5

Setting Up Direct Terminal Access to the FMA 2-5 Setting Up TELNET Access to the FMA 2-6

Connecting the FastModule to the Backplane 2-6

Assigning a Backplane Port to a Backplane Channel 2-7 Isolating a Backplane Port 2-8

Setting Up DMM Access 2-8

Setting Up Direct Terminal Access to the DMM 2-8 Configuring TELNET Access to the DMM 2-8

Configuring FMA for Management 2-11

Logging On 2-12

Assigning a Security Level 2-13

Keyboard Shortcuts 2-14 Using the FMA Management Setup Screen 2-14 Logging Off 2-16 Auto Logoff 2-17

Setting Up FMA Users 2-18

Creating a New User 2-19 Deleting a User 2-20 Editing User Details 2-21 Viewing Users 2-22 Assigning Local Security 2-22

3 BASIC FASTMODULE CONFIGURATION

Basic Configuration Guidelines 3-2

Basic Configuration Examples 3-2 Startup Defaults 3-4 Configuration Rules 3-5

CoreBuilder 5000 Slotting Considerations 3-6 Fast Ethernet Considerations 3-6 Full Duplex Considerations 3-6

Server Considerations 3-7 Configuring General Switch Parameters 3-7 Choosing a Switch Management Level 3-8 Setting Up the FastModule 3-11 Setting Up FastModule Ports 3-15

Specifying the Outlet Port 3-19

Switch Database (SDB) Description 3-19

Trap Notification 3-20 Adding Entries to the SDB 3-20 Configuring the Switch Database 3-21 Searching the Switch Database 3-22

Searching by MAC Address 3-22

Searching by Port 3-23

Adding an Entry Into the SDB 3-23 Deleting an Entry From the SDB 3-23

Setting Up Resilient Links 3-23

Rules for Setting Up Resilient Links 3-24 Viewing Resilient Link Setup 3-24 Configuring Resilient Links 3-26 Creating a Resilient Link 3-28

Deleting a Resilient Link 3-28 Setting Up Traps 3-29 Setting Up the Serial Port 3-30

vii

4 ADVANCED CONFIGURATION

VLAN Overview 4-2

VLAN Benefits 4-2 VLAN Example 4-3

Using VLANs With CoreBuilder 5000 FastModules 4-4

Understanding the Default VLAN 4-4 Connecting VLANs to a Router 4-4 Connecting Common VLANs Between FastModules 4-4

Sharing VLT Bandwidth 4-5 Using AutoSelect VLAN Mode 4-5 Using Non-Routable Protocols 4-6 Connecting Multiple Network Adapters to a FastModule 4-6

VLAN Configurations 4-7

Example 1 4-7 Example 2 4-8 Example 3 4-9

Setting Up VLANs 4-11

Assigning a Port to a VLAN 4-13 Specifying an Outlet Port 4-13 Specifying an Outlet Port as Part of a VLT 4-13 Setting Up VLANs Using AutoSelect VLAN Mode 4-14

Specifying Information About the VLAN Server 4-14 Specifying AutoSelect VLAN Mode 4-15

Spanning Tree Protocol Overview 4-16

STP Description 4-16 STP Operation 4-18

STP Initialization 4-18 STP Stabilization 4-19

STP Reconfiguration 4-20 Typical STP Configuration 4-21 Example STP Configurations 4-23

Setting Up Spanning Tree Protocol 4-25

Configuring VLAN STP Parameters 4-25 Configuring Port STP Parameters 4-28 Enabling STP on the FastModule 4-30

viii

5 STATUS MONITORING AND STATISTICS

Using the FastModule Management Agent 5-2

Viewing Summary Statistics 5-2

Changing Statistic Types 5-3

Clearing Statistics 5-4 Viewing Port Statistics 5-4 Viewing Port Traffic Statistics 5-6 Conducting Port Error Analysis 5-9 Monitoring Status 5-11 Viewing the Fault Log 5-12 Remote Polling 5-13

Using DMM Commands 5-14

Using the SHOW MODULE Command 5-14 Using the SHOW PORT Command 5-15

Using Graphical Interface Tools 5-16

Using Transcend LANsentry Software 5-16 Using CoreBuilder 5000 Manager 5-17 Using Device Management for Hubs 5-17

6 TROUBLESHOOTING

Troubleshooting Using LEDs 6-2

Verifying LED Operation 6-2 Reading the LEDs 6-2 Troubleshooting Module and Switch Status LEDs 6-3 Troubleshooting Port Status and Packet Activity LEDs 6-4

Resetting the FastModule 6-4

Saving the CoreBuilder 5000 Configuration 6-5 Using the Reset Button 6-5 Using the FastModule Management Agent 6-6 Using the DMM 6-6

Initializing the FastModule 6-7 Upgrading Software 6-8

Using the FMA Software Upgrade Screen 6-8 Using the Software Upgrade Configuration Utility 6-10

Troubleshooting Management Problems 6-11 Obtaining Technical Assistance 6-13

A SPECIFICATIONS

Mechanical Specifications A-2 Power Specifications A-2 Environmental Specifications A-3 Cable Specifications A-3 Cable Pinouts A-3

9-Pin to 25-Pin Crossover Cable A-4 9-Pin to 9-Pin Crossover Cable A-4 Modem Cable A-5 RJ-45 Pin Assignments A-5 Telco Pin Assignments A-6

B TECHNICAL SUPPORT

Online Technical Services B-1

World Wide Web Site B-2 3Com Bulletin Board Service B-2

Access by Analog Modem B-2

Access by Digital Modem B-2 3ComFacts Automated Fax Service B-3 3ComForum on CompuServe Online Service B-3

Support From Your Network Supplier B-4 Support From 3Com Corporation B-5 Returning Products for Repair B-6 Accessing the 3Com MIB B-6 Contacting 3Com Technical Publications B-7

INDEX

3COM CORPORATION LIMITED WARRANTY

FIGURES

1-1 24-Port FastModule 1-10 1-2 24-Port FastModule with FX Downlink 1-11 1-3 7-Port FX/TX FastModule 1-12 1-4 7-Port TX FastModule 1-13 1-5 Aggregator/Downlink FastModule 1-14 1-6 FastModule Backplane Connections 1-15 1-7 Aggregator/Downlink FastModule Backplane Connections 1-16 2-1 TEM/UNIX Tools for Configuring FastModules 2-3 2-2 TEM/Windows Tools for Configuring FastModules 2-4 2-3 FMA Screen Map 2-11 2-4 FMA Logon Screen 2-12 2-5 FMA Main Menu 2-13 2-6 Help Screen 2-14 2-7 Switch Management Setup Screen 2-15 2-8 Auto Logout Screen 2-17

2-9 User Access Levels screen 2-18 2-10 Create User Screen 2-19 2-11 Delete Users Screen 2-20 2-12 Edit User Screen 2-21 2-13 Switch Local Security Screen 2-22

3-1 Configuration Example 1 3-2

3-2 Configuration Example 2 3-3

3-3 Switch Management Screen – Port Level 3-8

3-4 Switch Management Screen – Unit Level 3-9

3-5 Switch Management Screen – VLAN Level 3-9

3-6 Switch Unit Setup Screen 3-11

3-7 Switch Port Setup Screen 3-15

3-8 Switch Unit Database View Screen 3-21

3-9 Unit Resilience Summary Screen 3-25 3-10 Port Resilience Screen 3-26 3-11 Trap Setup Screen 3-29 3-12 Serial Port Setup Screen 3-30

4-1 Example VLAN 4-3 4-2 VLAN Configuration With a Single FastModule 4-7 4-3 VLAN Configuration With Two 24-Port FastModules 4-8 4-4 VLAN Configuration With a 7-Port FX/TX FastModule 4-10 4-5 VLAN Setup Screen 4-11 4-6 VLAN Server Screen 4-14 4-7 Network With an Illegal Topology 4-16 4-8 STP Sends Traffic Flow Through Bridges C and A 4-17

4-9 STP Reroutes Traffic Flow Through Bridge B 4-18 4-10 Port Costs in a Network 4-21 4-11 STP Redundancy for Fast Ethernet Links 4-23 4-12 STP Redundancy for Cabling Error 4-24 4-13 VLAN STP ID Screen 4-25 4-14 VLAN STP Screen 4-26 4-15 Port STP Screen 4-28 4-16 Unit Setup Screen 4-30

5-1 Switch Summary Statistics Screen 5-2

5-2 Switch Port Statistics Screen 5-4

5-3 Port Traffic Statistics Screen 5-6

5-4 Port Error Analysis Screen 5-9

5-5 Switch Status Screen 5-11

5-6 Fault Log Screen 5-12

5-7 Switch Remote Poll Screen 5-13

6-1 Reset Screen 6-6

6-2 Initialization Screen 6-7

6-3 Software Upgrade Screen 6-9

A-1 9-Pin to RS-232 25-Pin Cable Pinouts A-4 A-2 9-Pin to 9-Pin Cable Pinouts A-4 A-3 9-Pin to RS-232 25-Pin Modem Cable Pinouts A-5

xii

TABLES

1-1 FastModule Names and Model Numbers 1-3 1-2 FastModule Packet Forwarding Process 1-5 1-3 Comparison of FastModules to Bridges 1-9 1-4 CoreBuilder 5000 Backplane Configurations 1-15 1-5 FastModule Backplane Port Assignments 1-16 1-6 Aggregator/Downlink FastModule Backplane Port Assignments 1-17 2-1 Backplane Port Connections 2-7 2-2 Default Users 2-12 3-1 Startup Default Settings 3-4 3-2 FastChannel Assignment Effect on Backplane Channels 3-6 3-3 FastModule Port IDs 3-10 4-1 Default Root Path Costs 4-19 6-1 Module and Backplane Status LED Troubleshooting 6-3 6-2 Port Status and Packet Activity LED Troubleshooting 6-4 6-3 Software Upgrade Configuration Utility Commands 6-10

6-4 FastModule Management Problems 6-11 A-1 CoreBuilder 5000 FastModule Mechanical Specifications A-2 A-2 CoreBuilder 5000 FastModule Power Specifications A-2 A-3 CoreBuilder 5000 FastModule Fuse Specifications A-2 A-4 CoreBuilder 5000 FastModule Environmental Specifications A-3 A-5 Required Cable Type and Maximum Segment Length A-3 A-6 Pin Assignments for Ports Configured as MDI A-5 A-7 Pin Assignments for Ports Configured as MDIX A-6 A-8 Pin Assignments for Telco Ports 1 to 12 A-6 A-9 Pin Assignments for Telco Ports 13 to 24 A-7

xiii

ABOUT THIS GUIDE

3Com CoreBuilder™ 5000 FastModules are high-performance LAN-switching modules for the 3Com

CoreBuilder 5000 Integrated

System Hub.

This guide describes how to install, configure, and manage 3Com CoreBuilder 5000 FastModules.

If the information in the release notes shipped with your product differs from the information in this guide, follow the release note instructions.

Audience This guide is intended for the following people at your site:

■ Network manager or administrator

■ Trained hardware installer or service personnel

How to Use This

The following table shows the location of specific information.

Guide

If you are looking for: Turn to:

FastModule features and general descriptions Chapter 1 Information on setting up FastModule management Chapter 2 Information on configuring FastModules Chapter 3 VLAN overview and configuration information Chapter 4 Information on monitoring FastModule operation Chapter 5 Information on troubleshooting FastModule LEDs, management

problems, and resetting FastModules Detailed FastModule specifications and cable pinouts Appendix A 3Com technical support information Appendix B

Chapter 6

2 About This Guide

Conventions The following tables list conventions used throughout this guide:

Icon Notice Type Alerts you to...

Information note Important features or instructions

Caution Risk of personal safety, system damage, or loss

of data

Warning Risk of severe personal injury

Convention Description

Syntax Syntax means you must evaluate the syntax provided and

supply the appropriate values. Placeholders for values you must supply appear in angle brackets. Example:

Enable RIPIP by using the following syntax:

SETDef ault !<por t> -RIPIP CONTrol = Listen

In this example, you must supply a port number for <port>.

Commands Command means you must enter the command exactly as

Screen displays This font represents information as it appears on the

The words enter and type

shown in text and press the Return or Enter key. Example:

To remove the IP address, enter the following command:

SETDef ault !0 -IP NETaddr = 0. 0.0.0

This guide always gives the full form of a command in uppercase and lowercase letters. However, you can abbreviate commands by entering only the uppercase letters and the appropriate value. Commands are not case-sensitive.

screen. Enter means type something, and then press the Return or

Enter key. Do not press the Return or Enter key when an instruction says type.

INTRODUCTION

This chapter describes the features and components of 3Com CoreBuilder chapter contains the following sections:

■ FastModule Overview

■ FastModule Names

■ FastModule Features

■ Comparing FastModules to Bridges

■ FastModule Descriptions

■ FastModule Backplane Connections



5000 FastModules and their principles of operation. This

1-2 CHAPTER 1: INTRODUCTION

FastModule Overview

CoreBuilder 5000 FastModules are high-performance LAN-switching modules for the 3Com

CoreBuilder 5000 Integrated System Hub. Based on the BRASICA Application Specific Integrated Circuit (ASIC), the FastModule family extends switching from the backbone, enabling you to provide your users with greater bandwidth, faster throughput, and high-speed connections.

WorkGroup Solutions The 24-Port 10BASE-T FastModule provides switched 10BASE-T

connectivity to the workgroup and allows for one switched connection to one of four CoreBuilder 5000 FastChannel backplane networks.

The 24-Port 10BASE-T FastModule with FX Downlink provides the same switched 10BASE-T connectivity to the workgroup with an additional 100BASE-FX port for connection to Fast Ethernet backbone networks.

FastEthernet

Solutions

Support for collapsed Fast Ethernet backbones and large central server farms is provided by the following FastModules:

■ 7-Port 100BASE-FX/TX FastModule – Provides five FX-port and two

TX-port switched Fast Ethernet connections to any one of four CoreBuilder 5000 FastChannel backplane networks. When used in conjunction with other CoreBuilder 5000 FastModules, this FastModule lets you create backbone and floor configurations based on shared and switched Fast Ethernet and Ethernet.

■ 7-Port 100BASE-TX FastModule – Provides seven TX-port switched

Fast Ethernet connections to any one of four CoreBuilder 5000 FastChannel backplane networks.

■ Aggregator/Downlink FastModule (with an optional FX, TX, or ATM

downlink port) – Consolidates traffic from up to four CoreBuilder 5000 FastChannel backplane networks and three Ethernet backplane segments within a single CoreBuilder 5000 hub. The 100BASE-FX front panel port provides a downlink connection into a switched Fast Ethernet backbone network. Three daughter card options are available, providing one additional downlink port using 100BASE-FX, 100BASE-TX, or 155 Mbps ATM technology.

FastModule Names 1-3

FastModule Names Table 1-1 correlates each type of FastModule with its model number

and maps the full product name to the shortened name used throughout this document:

Table 1-1 FastModule Names and Model Numbers

FastModule Name Model Number Shortened Name

CoreBuilder 5000 24-Port 10BASE-T FastModule

CoreBuilder 5000 24-Port 10BASE-T FastModule with FX Downlink

CoreBuilder 5000 7-Port 100BASE-FX/TX FastModule

CoreBuilder 5000 7-Port 100BASE-TX FastModule

CoreBuilder 5000 Aggregator/Downlink FastModule

3C96524M-TP 24-Port

FastModule

3C96525M-TPFX 24-Port

FastModule with FX Downlink

3C96507M-FXTX 7-Port FX/TX

FastModule

3C96507M-TX 7-Port TX

FastModule

3C96501M-BFX Downlink

FastModule

FastModule Features

For more information about Downlink FastModule option cards, refer to the installation document that accompanies the option card.

FastModule features are described in the sections below:

■ Scalable Performance

■ Packet-Forwarding Modes

■ Outlet Port

■ Intelligent Flow Management

■ Full Duplex Support

■ Security

■ Resilient Links

■ Virtual LANs (VLANs)

■ PACE Technology

■ Spanning Tree Protocol

■ VLAN Server

1-4 CHAPTER 1: INTRODUCTION

Scalable Performance Each FastModule is equipped with its own high performance switching

Application Specific Integrated Circuit (ASIC). 3Com BRASICA ASIC technology provides scalable performance for switching on each port.

Packet-Forwarding

Modes

The 10 Mbps front panel ports on the 24-Port FastModule and 24-Port FastModule with FX Downlink can operate in any of the following forwarding modes:

■ Fast Forward – Frames are forwarded as soon as the destination

address is received and verified.

■ Fragment Free – A minimum of 64 bytes of the received frame is

buffered before the frame is forwarded.

■ Store and Forward – Received packets are buffered in their entirety

before forwarding. This ensures that only good frames are passed to their destination.

■ Intelligent – The FastModule monitors the amount of error traffic

on the network and changes the forwarding mode accordingly.

Error traffic is defined as:

■ alignment errors

■ CRC errors

■ long frame errors

■ short events

■ collisions

If the FastModule detects:

■ less than 18 errors per second, it will operate in FastForward

mode.

■ more than 18 errors per second, it will operate in Store and

Forward mode until the number of errors returns to 0.

The 7-Port FX/TX FastModule, 7-Port TX FastModule, and Downlink FastModule operate in Store and Forward mode only.

FastModule Features 1-5

Outlet Port In the 24-Port FastModule only, you can designate any port to act as an

outlet port. The outlet port serves as an exit path for any packet that arrives at a FastModule with an unknown destination address. By default, the backplane port on the 24-Port FastModule (port 25) is designated as the outlet port.

For more information about designating a outlet port, refer to Setting

Up VLANs on page 4-11.

Table 1-2

shows how a packet is processed when it arrives at the FastModule, and delineates the difference between the action performed by the 24-Port FastModule versus all other FastModules.

Table 1-2 FastModule Packet Forwarding Process

24-Port FastModule With

Packet Source

Any port EXCEPT outlet port (Unicast packet)

Any port EXCEPT outlet port (Multi/Broadcast packet)

Outlet port (Unicast packet)

Outlet port (Multi/Broadcast packet)

Destination Address

Unknown Forward to outlet port only Flood to all ports Flood to all ports

Same port as source address

Another port (not outlet port)

Not applicable Flood to all ports within

Unknown Filter (discard) N/A (no outlet port

Known on a port (not outlet port)

Not applicable Flood to all ports within

Bridging Mode Set to Forward to Outlet

Filter (discard) Filter (discard) Filter (discard)

Forward to specific port only

same VLAN as source port

Forward to specific port only

specific VLAN

Action

24-Port FastModule With Bridging Mode Set to Forward to All

Forward to specific port only

Flood to all ports within same VLAN as source port

designation) N/A (no outlet port

designation)

N/A (no outlet port designation)

All Other FastModules

Forward to specific port only

Flood to all ports within same VLAN as source port

N/A (no outlet port designation)

1-6 CHAPTER 1: INTRODUCTION

Intelligent Flow

Management

Intelligent Flow Management (IFM) is a congestion control mechanism built into the FastModule. Congestion is caused by one or more devices sending traffic to a FastModule port that is already busy.

IFM is available only on the FastModule front panel ports.

The FastModule contains both input and output packet buffers. While congestion is rare, IFM is designed to alleviate problems when packet buffers in the FastModule are full. IFM prevents packet loss by preventing the transmitting device from sending any further packets until the port is no longer congested.

If a packet arrives at a conventional switch that does not operate IFM, and that port is congested (resulting in packet loss), the transmitting device is unaware of this. The originating station may retransmit the packets, effectively wasting bandwidth.

A FastModule using IFM senses congestion, and prevents packet loss by inhibiting the transmitting device from transmitting the packet in the first place. It does this by forcing the device to retransmit the packet later. This “back-off” and retransmission occurs quickly (typically less than 1 second) and is much faster than waiting for the transmitting device to time-out.

There are two benefits:

■ The packet is transmitted quickly and successfully

■ The packet is only transmitted once, saving bandwidth

If the FastModule is connected to a repeated segment with local traffic, and the FastModule invokes IFM on the repeated segment, the FastModule would not only inhibit the devices transmitting to the congested port, but also inhibit devices on the segment transmitting to each other.

IFM does not operate in Full Duplex mode.

Full Duplex Support The FastModule provides full duplex capability on all front panel Fast

Ethernet ports. Full duplex capability allows frames to be transmitted and received simultaneously, in effect doubling bandwidth available on a link. Full duplex capability also supports 100BASE-FX cable runs of up to 2 km.

FastModule Features 1-7

Security Security is available on the 10 Mbps front panel ports of the 24-Port

FastModule and 24-Port FastModule with FX Downlink. FastModule security prevents users from connecting unauthorized stations to the network through the front panel ports. You enable security using the FastModule Management Agent. When security is enabled on a port, that port enters into a single address learning mode. This port is then permitted to learn just a single Ethernet address. After that address is learned, if the FastModule sees a different address on that port, the port will be disabled. Until security is disabled, no other address can be learned.

Resilient Links You can set up resilient links on FastModule front panel ports only.

Resilient links enable you to protect critical links and prevent wasteful network downtime if the link fails. If a main communication link fails, a standby duplicate link automatically takes over the task of the main link. Each main and standby link pair is referred to as a resilient link pair. The main and standby links must be set up on the same FastModule.

Virtual LANs (VLANs) The Virtual LAN (VLAN) feature allows you to build your network

segments without being restricted by physical connections. A VLAN is defined as a group of location- and topology-independent devices that communicate as if they are on the same physical LAN.

Implementing VLANs on your network has three advantages:

■ When you move a workstation, minimal physical intervention is

required. Within the VLAN setup, you can configure a group of devices on different floors in a building into a common communications group. For example, if you move a workstation from VLAN 1 to VLAN 2, you only need to know address information for that device. The physical location of the port is irrelevant.

■ Use of network resources becomes much more efficient. You can set

up each VLAN to contain only those devices which need to communicate with each other.

■ Network security is enhanced. Devices within the same VLAN can

only communicate with member devices in the same VLAN. For example, if a device in VLAN 1 needs to communicate with devices in VLAN 2, you configure the device to cross the router between VLAN 1 and VLAN 2.

1-8 CHAPTER 1: INTRODUCTION

PACE Technology 3Com PACE Technology allows you to carry multimedia applications

using voice and video traffic over standard Ethernet and Fast Ethernet LANs. PACE Technology provides the quality of service that these applications require, reducing latency to a minimum and prioritizing the multimedia traffic.

Both multimedia and data traffic are improved considerably by:

■ Introducing an Ethernet switch into the LAN

■ Attaching each end-station to its own dedicated 10 Mbps switch

port

This removes any contention between different end-stations for the Ethernet bandwidth. However, when 2-way traffic passes between an end-station and the switch port, access to the bandwidth can still be unfairly allocated to traffic in one direction, resulting in poor quality video display. PACE Technology allocates the available bandwidth fairly to traffic in each direction. You can use existing Ethernet adapters and cabling to run high-quality multimedia sessions across the LAN.

You can enable PACE Technology to operate on the same CoreBuilder 5000 backplane FastChannel between a maximum of two FastModules installed in the same hub.

Spanning Tree

Protocol

Spanning Tree Protocol (STP) is part of the IEEE 802.1D bridging specification that provides a system of allowing parallel paths for network traffic while allowing:

■ A redundant path is disabled when a parallel main path is

operational

■ A redundant path is enabled if a parallel main path fails

Refer to Spanning Tree Protocol Overview in Chapter 2 for more information.

VLAN Server The VLAN Server function allows you to create a VLAN Server database

from which you can set FastModule ports to automatically receive assignment to a VLAN.

Refer to Using AutoSelect VLAN Mode

in Chapter 4.

Comparing FastModules to Bridges 1-9

Comparing FastModules to Bridges

Table 1-3 shows FastModule operation compared to that of an IEEE

802.1D bridge.

ways except for those shown in Table 1-3

Table 1-3 Comparison of FastModules to Bridges

Feature

Address Learning

Forwarding Mode

Operation when packet buffers full

Spanning Tree

Action on Unknown Destination Address

Database size

Bridge and FastModule operation is identical in all

IEEE

802.1D Bridge

All ports All ports (except

Store and forward

Discard packets

Supported Supported Supported Supported

Flood all ports

Variable 500 addresses 4080 addresses 4080 addresses

24-Port FastModule

outlet when Bridging Mode = Forward to Outlet)

Fast Forward, Fragment Free, Store and Forward, or Intelligent

If enabled, IFM is invoked to suppress transmissions at source.

Forward to outlet port only (when Bridging Mode = Forward to Outlet)

24-Port FastModule w/ FX Downlink

All ports All ports

Fast Forward, Fragment Free, Store and Forward, or Intelligent

If enabled, IFM is invoked to suppress transmissions at source.

Flood all ports Flood all ports

All Other FastModules

Store and forward only

If enabled, IFM is invoked to suppress transmissions at source.

FastModule Descriptions

This section describes the following FastModules:

■ 24-Port FastModule

■ 24-Port FastModule with FX Downlink

■ 7-Port FX/TX FastModule

■ 7-Port TX FastModule

■ Aggregator/Downlink FastModule

1-10 CHAPTER 1: INTRODUCTION

24-Port FastModule The CoreBuilder 5000 24-Port FastModule provides 24 switched

Ethernet ports for connecting network devices to any of four available CoreBuilder 5000 FastChannel backplanes using shielded or unshielded twisted-pair cabling. The 24 10BASE-T-compliant ports are provided through two Telco connectors on the FastModule front panel.

10BASE-T ports 1 to 12

10BASE-T ports 13 to 24

Figure 1-1

24-Port FastModule

Out-of-band console port connection

shows the 24-Port FastModule.

SWITCH-STAT

Reset button

CoreBuilder 5000 FastChannel Backplane

Backplane port 25

1 3 5 7 9 11 13 15 17 19 21 23

MOD-STAT

RESET

1X-12X

13X-24X

Module Status/

2 4 6

8 10 12 14 16 18 20 22 24

Switch Status LEDs

Port Status LEDs

Telco connector (ports 1 to 12)

Telco connector (ports 13 to 24)

Figure 1-1 24-Port FastModule

CONSOLE

Console port

6524M-TP

FastModule Descriptions 1-11

24-Port FastModule

with FX Downlink

10BASE-T ports 1 to 12

10BASE-T ports 13 to 24

100BASE-FX port 26

The 24-Port FastModule with FX Downlink is similar to the 24-Port FastModule, and includes an additional switched 100BASE-FX downlink port using an SC connector to connect to Fast Ethernet backbone networks.

Figure 1-2

24-Port FastModule with FX Downlink

shows the 24-Port FastModule with FX Downlink front panel.

SWITCH-STAT

Reset button

CoreBuilder 5000 FastChannel Backplane

MOD-STAT

RESET

8 10

9 11

1X-12X

13X-24X

Module Status/ Switch Status LEDs

Port Status LEDs

Telco connector (ports 1 to 12)

Telco connector (ports 13 to 24)

Out-of-band console port connection

Backplane port 25

100BASE-FX port 26

CONSOLE

Console port

6525M-TPFX

Figure 1-2 24-Port FastModule with FX Downlink

Using a 90° Telco connector cable on the bottom Telco port physically prevents access to the 100BASE-FX port. Use either a 180° or 45° cable. You can order a 45° cable through 3Com. Refer to Appendix A for details.

1-12 CHAPTER 1: INTRODUCTION

7-Port FX/TX

FastModule

100BASE-FX ports 1 to 5

The CoreBuilder 5000 7-Port FX/TX FastModule provides:

■ Five 100BASE-FX ports using SC connectors which can be used as

downlink connections to the data center

■ Two 100BASE-TX ports using RJ-45 connectors which can be used

to provide dedicated 100 Mbps connections to workgroup servers

Figure 1-3

7-Port FX/TX FastModule

shows the 7-Port FX/TX FastModule front panel.

SWITCH-STAT

Reset button

CoreBuilder 5000 FastChannel Backplane

PACKET

MOD-STAT

RESET

STATUS

1 2 3 4 5 6 7

Module Status/ Switch Status LEDs

Packet Activity/ Port Status LEDs

100BASE-FX ports 1 to 5

100BASE-TX ports 6 to 7

Out-of-band console port

Backplane port 8

connection

Figure 1-3 7-Port FX/TX FastModule

100BASE-TX ports 6 to 7

CONSOLE

Console port

6507M-TXFX

+ 148 hidden pages

3com CoreBuilder 5000 FastModule User Guide

Specifications and Main Features

Frequently Asked Questions

User Manual

CONTENTS

FIGURES

TABLES

ABOUT THIS GUIDE

Audience This guide is intended for the following people at your site:

Conventions The following tables list conventions used throughout this guide:

Related Documents 3

■ 3Com Documents

Reference Documents The following documents supply related background information:

INTRODUCTION

FastModule Overview

WorkGroup Solutions The 24-Port 10BASE-T FastModule provides switched 10BASE-T

FastModule Names 1-3

FastModule Features

Scalable Performance Each FastModule is equipped with its own high performance switching

Outlet Port In the 24-Port FastModule only, you can designate any port to act as an

Full Duplex Support The FastModule provides full duplex capability on all front panel Fast

Security Security is available on the 10 Mbps front panel ports of the 24-Port

Resilient Links You can set up resilient links on FastModule front panel ports only.

Virtual LANs (VLANs) The Virtual LAN (VLAN) feature allows you to build your network

PACE Technology 3Com PACE Technology allows you to carry multimedia applications

VLAN Server The VLAN Server function allows you to create a VLAN Server database

Comparing FastModules to Bridges

FastModule Descriptions

24-Port FastModule

24-Port FastModule with FX Downlink

7-Port FX/TX FastModule