Cabletron Systems FAST NETWORK 100 User manual

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FAST NETWORK 100

USER GUIDE

Fast Network 100 User Guide i

NOTICE

Cabletron Systems reserves the right to make changes in speciﬁcations and other information

contained in this document without prior notice. The reader should in all cases consult Cabletron

Systems to determine whether any such changes have been made.

The hardware, ﬁrmware, or software described in this manual is subject to change without notice.

IN NO EVENT SHALL CABLETRON SYSTEMS BE LIABLE FOR ANY INCIDENTAL,

INDIRECT, SPECIAL, OR CONSEQUENTIAL DAMAGES WHATSOEVER (INCLUDING BUT

NOT LIMITED TO LOST PROFITS) ARISING OUT OF OR RELATED TO THIS MANUAL OR

THE INFORMATION CONTAINED IN IT, EVEN IF CABLETRON SYSTEMS HAS BEEN

ADVISED OF, KNOWN, OR SHOULD HAVE KNOWN, THE POSSIBILITY OF SUCH

DAMAGES.



Printed in the United States of America

Order Number: 9031866-01 May 1996

All product names mentioned in this manual may be trademarks or registered trademarks of their

respective companies.

Printed on Recycled Paper

Notice

ii Fast Network 100 User Guide

FCC NOTICE

This device complies with Part 15 of the FCC rules. Operation is subject to the following two

conditions: (1) this device may not cause harmful interference, and (2) this device must accept any

interference received, including interference that may cause undesired operation.

NOTE:

This equipment has been 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 uses, generates, and can radiate radio frequency energy and if not installed in

accordance with the operator’s manual, may cause harmful interference to radio communications.

Operation of this equipment in a residential area is likely to cause interference in which case the user

will be required to correct the interference at his own expense.

WARNING:

Changes or modifications made to this device which are not expressly approved by the

party responsible for compliance could void the user’s authority to operate the equipment.

DOC NOTICE

This digital apparatus does not exceed the Class A limits for radio noise emissions from digital

apparatus set out in the Radio Interference Regulations of the Canadian Department of

Communications.

Le présent appareil numérique n’émet pas de bruits radioélectriques dépassant les limites applicables

aux appareils numériques de la class A prescrites dans le Règlement sur le brouillage radioélectrique

édicté par le ministère des Communications du Canada.

VCCI NOTICE

This equipment is in the 1st Class Category (information equipment to be used in commercial and/or

industrial areas) and conforms to the standards set by the Voluntary Control Council for Interference

by Information Technology Equipment (VCCI) aimed at preventing radio interference in commercial

and/or industrial areas.

Consequently, when used in a residential area or in an adjacent area thereto, radio interference may be

caused to radios and TV receivers, etc.

Read the instructions for correct handling.

Notice

Fast Network 100 User Guide iii

CABLETRON SYSTEMS, INC. PROGRAM LICENSE AGREEMENT

IMPORTANT:

Before utilizing this product, carefully read this License Agreement.

This document is an agreement between you, the end user, and Cabletron Systems, Inc. (“Cabletron”)

that sets forth your rights and obligations with respect to the Cabletron software program (the

“Program”) contained in this package. The Program may be contained in ﬁrmware, chips or other

media. BY UTILIZING THE ENCLOSED PRODUCT, YOU ARE AGREEING TO BECOME

BOUND BY THE TERMS OF THIS AGREEMENT, WHICH INCLUDES THE LICENSE AND

THE LIMITATION OF WARRANTY AND DISCLAIMER OF LIABILITY. IF YOU DO NOT

AGREE TO THE TERMS OF THIS AGREEMENT, PROMPTLY RETURN THE UNUSED

PRODUCT TO THE PLACE OF PURCHASE FOR A FULL REFUND.

CABLETRON SOFTWARE PROGRAM LICENSE

1. LICENSE

. You have the right to use only the one (1) copy of the Program provided in this

package subject to the terms and conditions of this License Agreement.

You may not copy, reproduce or transmit any part of the Program except as permitted by the

Copyright Act of the United States or as authorized in writing by Cabletron.

2. OTHER RESTRICTIONS. You may not reverse engineer, decompile, or disassemble the

Program.

3. APPLICABLE LAW. This License Agreement shall be interpreted and governed under the laws

and in the state and federal courts of New Hampshire. You accept the personal jurisdiction and

venue of the New Hampshire courts.

EXCLUSION OF WARRANTY AND DISCLAIMER OF LIABILITY

1. EXCLUSION OF

WARRANTY. Except as may be specifically provided by Cabletron in

writing, Cabletron makes no warranty, expressed or implied, concerning the Program (including

its documentation and media).

CABLETRON DISCLAIMS ALL WARRANTIES, OTHER THAN THOSE SUPPLIED TO

YOU BY CABLETRON IN WRITING, EITHER EXPRESSED OR IMPLIED, INCLUDING

BUT NOT LIMITED TO IMPLIED WARRANTIES OF MERCHANTABILITY AND

FITNESS FOR A PARTICULAR PURPOSE, WITH RESPECT TO THE PROGRAM, THE

ACCOMPANYING WRITTEN MATERIALS, AND ANY ACCOMPANYING HARDWARE.

2. NO LIABILITY FOR CONSEQUENTIAL DAMAGES. IN NO EVENT SHALL

CABLETRON OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER

(INCLUDING, WITHOUT LIMITATION, DAMAGES FOR LOSS OF BUSINESS,

PROFITS, BUSINESS INTERRUPTION, LOSS OF BUSINESS INFORMATION, SPECIAL,

INCIDENTAL, CONSEQUENTIAL, OR RELIANCE DAMAGES, OR OTHER LOSS)

ARISING OUT OF THE USE OR INABILITY TO USE THIS CABLETRON PRODUCT,

EVEN IF CABLETRON HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH

DAMAGES. BECAUSE SOME STATES DO NOT ALLOW THE EXCLUSION OR

LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES, OR

ON THE DURATION OR LIMITATION OF IMPLIED WARRANTIES, IN SOME

INSTANCES THE ABOVE LIMITATIONS AND EXCLUSIONS MAY NOT APPLY TO

YOU.

Notice

iv Fast Network 100 User Guide

UNITED STATES GOVERNMENT RESTRICTED RIGHTS

The enclosed product (a) was developed solely at private expense; (b) contains “restricted computer

software” submitted with restricted rights in accordance with Section 52227-19 (a) through (d) of the

Commercial Computer Software - Restricted Rights Clause and its successors, and (c) in all respects

is proprietary data belonging to Cabletron and/or its suppliers.

For Department of Defense units, the product is licensed with “Restricted Rights” as deﬁned in the

DoD Supplement to the Federal Acquisition Regulations, Section 52.227-7013 (c) (1) (ii) and its

successors, and use, duplication, disclosure by the Government is subject to restrictions as set forth in

subparagraph (c) (1) (ii) of the Rights in Technical Data and Computer Software clause at 252.227-

7013. Cabletron Systems, Inc., 35 Industrial Way, Rochester, New Hampshire 03867-0505.

Fast Network 100 User Guide v

CONTENTS

CHAPTER 1 INTRODUCTION

1.1 Getting Help.................................................................................1-2

1.2 Document Conventions...............................................................1-2

1.3 Related Documentation...............................................................1-3

1.4 Overview......................................................................................1-4

1.4.1 OSI Compliance..............................................................1-7

1.5 FN100 Architecture......................................................................1-8

1.5.1 Store and Forward Switching..........................................1-8

1.5.2 Spanning Tree Algorithm................................................1-9

1.5.3 FN100 Bridge Address Table .........................................1-9

1.6 FN100 Applications ...................................................................1-11

1.6.1 Server Farms................................................................1-11

1.6.2 High-Performance Workgroups ....................................1-12

1.6.3 Backbones....................................................................1-13

1.7 FN100 Configurations................................................................1-13

1.7.1 Trunking Configurations................................................1-14

1.7.1.1 Trunking Configuration Examples................1-15

1.7.2 Virtual Switch Configurations........................................1-16

1.7.2.1 Virtual Switch Configuration Examples ........1-17

1.7.3 Workgroups ..................................................................1-18

1.7.3.1 Workgroup Configuration Example ..............1-18

CHAPTER 2 UNPACKING AND INSTALLING THE FN100

2.1 FN100 Panels..............................................................................2-1

2.2 Power Switch...............................................................................2-2

2.3 Installing the FN100.....................................................................2-2

2.3.1 Table-Mounting the FN100.............................................2-2

2.3.2 Rack-Mounting the FN100..............................................2-3

2.3.3 Checking the Power-up Diagnostics Sequence..............2-4

2.4 Connecting the Local Console Manager .....................................2-5

Contents

vi Fast Network 100 User Guide

2.5 Local Console Manager Overview...............................................2-6

2.6 Command Syntax Conventions ...................................................2-6

2.6.1 Basic LCM Commands....................................................2-7

2.6.1.1 help.................................................................2-8

2.6.1.2 erase...............................................................2-8

2.6.1.3 exit ..................................................................2-8

2.6.1.4 logout..............................................................2-8

2.7 Connecting the FN100 to the Network.........................................2-9

2.7.1 Punch-Down Block and Patch Panel Connections..........2-9

2.7.2 Direct Device Connections..............................................2-9

2.7.3 Wiring Considerations...................................................2-10

CHAPTER 3 CONFIGURING THE FN100

3.1 Assigning IP Addresses...............................................................3-2

3.1.1 Displaying IP Addresses .................................................3-3

3.1.2 Deleting an IP Address....................................................3-3

3.1.3 Changing a Subnet Mask................................................3-4

3.2 Setting Port Speed.......................................................................3-4

3.3 Enabling Bridging.........................................................................3-5

3.4 Disabling Bridging........................................................................3-6

3.5 Displaying Bridging Functions......................................................3-6

3.6 Trunking.......................................................................................3-6

3.7 Disabling Trunking .......................................................................3-8

3.8 Displaying Trunking Status ..........................................................3-8

3.9 Defining and Deleting Virtual Switches......................................3-10

3.9.1 Displaying Virtual Switch Information............................3-11

3.9.2 Creating and Modifying Virtual Switches.......................3-11

3.10 Defining and Deleting Workgroups ............................................3-12

3.11 Local Address Filtering ..............................................................3-14

3.12 Assigning a Community Name...................................................3-15

3.13 Configuring Multicast Storm Protection......................................3-16

3.14 Modifying MIB Variables ............................................................3-17

3.14.1 System Contact.............................................................3-17

3.14.2 System Name................................................................3-18

3.14.3 System Location............................................................3-18

3.14.4 Authentication Password...............................................3-18

3.14.4.1 Set Password................................................3-18

3.14.4.2 Get Password ...............................................3-19

3.14.5 Aging Parameter ...........................................................3-19

Contents

Fast Network 100 User Guide vii

CHAPTER 4 MONITORING AND MANAGING THE FN100

4.1 FN100 Management Tools..........................................................4-1

4.2 FN100 Statistics ..........................................................................4-2

4.2.1 Gathering Statistics.........................................................4-2

4.2.2 System Statistics ............................................................4-3

4.2.3 Ethernet Port Statistics ...................................................4-3

4.2.4 SNMP Statistics..............................................................4-5

4.3 Using LCM to Check FN100 Status.............................................4-6

4.3.1 Displaying Status............................................................4-6

4.3.2 Displaying MAC Addresses ............................................4-8

4.3.3 Displaying Manufacturing Information ..........................4-11

4.4 Using LCM to Manage the FN100.............................................4-12

4.4.1 Disabling a Port ............................................................4-12

4.4.2 Enabling a Port .............................................................4-13

4.4.2.1 NoRIP Option...............................................4-13

4.4.3 Changing a Subnet Mask .............................................4-14

4.4.4 Changing a Community Name......................................4-14

4.4.5 Setting the Baud Rate...................................................4-15

4.4.6 Setting a Reboot Time..................................................4-16

CHAPTER 5 FN100 DIAGNOSTICS AND TROUBLESHOOTING

5.1 Power-up Diagnostics..................................................................5-1

5.1.1 Power-Up LED Sequence...............................................5-1

5.1.2 Specific Power-Up Tests ................................................5-2

5.1.3 Software Checksum Comparison ...................................5-2

5.1.4 Power-Up Diagnostics Results .......................................5-3

5.2 Responses to Failures at Power Up............................................5-3

5.3 Status and Activity Indicators ......................................................5-3

5.4 Troubleshooting...........................................................................5-5

5.4.1 FN100 Does Not Power Up ............................................5-5

5.4.2 Power Supply Fuse.........................................................5-6

5.4.3 Connectivity Problems....................................................5-6

5.4.4 FN100 Has Rebooted.....................................................5-7

5.4.5 FN100 Does Not Respond to NMS.................................5-7

Contents

viii Fast Network 100 User Guide

APPENDIX A TECHNICAL SPECIFICATIONS

A.1 FN100 Specifications.................................................................. A-1

A.2 Types/Connectors.......................................................................A-3

A.3 Cable Specifications ...................................................................A-3

A.3.1 10BASE-T Cable Specifications.....................................A-3

A.3.2 100BASE-TX Cable Specifications................................. A-4

A.3.3 100BASE-FX Cable Specifications................................. A-4

A.4 Management Cable Pin Assignments.........................................A-5

A.5 10BASE-T and 100BASE-TX Pin Assignments..........................A-5

A.5.1 Connectors .....................................................................A-6

A.6 Straight-Through Wiring..............................................................A-7

A.7 Crossover Wiring ........................................................................A-7

A.8 Limitations and Restrictions........................................................ A-7

APPENDIX B GLOSSARY

INDEX

Fast Network 100 User Guide Page 1-1

CHAPTER 1

INTRODUCTION

This manual is for system administrators responsible for installing,

conﬁguring, monitoring, and maintaining the Cabletron Systems Fast

Network 100 (FN100) switch. You should have a familiarity with

networking concepts and principles. In addition, a basic understanding of

Simple Network Management Protocol (SNMP) is helpful.

This manual provides instructions for using the FN100’s internal Local

Console Manager (LCM) to set basic conﬁguration parameters. When it is

not possible to use LCM, general instructions and guidelines applicable to

most Network Management Software (NMS) systems are provided.

The contents of each chapter are described below.

• Chapter 1,

Introduction

, describes the available conﬁgurations of the

FN100, the features and functions of the FN100, and introduces

Cabletron Systems’ Local Console Manager (LCM) for managing the

FN100.

• Chapter 2,

Unpacking and Installing the FN100

, describes the

FN100 front panels, how to install the FN100, how to initiate an LCM

session, and how to connect the FN100 to the network.

• Chapter 3,

Configuring the FN100

, provides instructions for

conﬁguring the FN100 using LCM. It also provides some common

Management Information Base (MIB) variables that you may decide

to change through your NMS.

• Chapter 4,

Monitoring and Managing the FN100

, describes how to

monitor FN100 status and statistics. It also describes how to manage

the FN100 ports using LCM.

• Chapter 5,

FN100 Diagnostics and Troubleshooting

, describes the

FN100 diagnostics and provides information on troubleshooting

common problems.

Chapter 1:

Introduction

Page 1-2 Fast Network 100 User Guide

• Appendix A,

Technical Specifications

, provides the FN100

speciﬁcations and basic 10BASE-T and 100BASE-TX cabling pin

assignments.

• Appendix B,

Glossary

, provides a glossary of terms both speciﬁc to

the FN100 and common to the networking ﬁeld.

1.1 GETTING HELP

If you need additional support related to this device, or if you have any

questions, comments, or suggestions concerning this manual, contact

Cabletron Systems Technical Support:

By phone (603) 332-9400

Monday – Friday; 8

A

.

M

. – 8

P

.

M

. Eastern Time

By CompuServe GO CTRON from any ! prompt

By Internet mail [email protected]

By FTP ctron.com (134.141.197.25)

Login

anonymous

Password

your email address

1.2 DOCUMENT CONVENTIONS

The following conventions are used throughout this document:

LCM commands, prompts, and information displayed by the computer

appear in Courier typeface, for example:

Current Number of Learned Addresses: 133

Information that you enter appears in Courier bold typeface, for example:

FN100 >

status

Information that you need to enter with a command is represented in

capital letters and enclosed in angle brackets < >. For example, you must

enter a port number and an IP address to execute the

ipaddr

<PORT#>

command:

FN100 >

ipaddr 6 192.138.217.40

Field value options appear in bold typeface. For example, FN100 bridging

options include

off

,

on

, and

noBPDU

.

Related Documentation

Fast Network 100 User Guide Page 1-3

1.3 RELATED DOCUMENTATION

You may need to refer to the following documentation:

•

Fast Network 100 MIB

Reference Guide

– contains the

enterprise MIB.

If you need internetworking reference material, you may ﬁnd the

following books helpful:

•

Interconnections, Bridges and Routers,

Radia Perlman, Addison

•

Internetworking with TCP/IP: Principles, Protocols, and Architecture

•

The Simple Book, An Introduction to Management of TCP/IP-based

internets

, Marshall T. Rose, Prentice Hall © Second Edition, 1994.

1.4 OVERVIEW

The FN100 is an intelligent Fast Ethernet switch that supports 10 Mbps or

100 Mbps connectivity on up to 16 ports over Category 5 Unshielded

Twisted Pair (UTP), and 100 Mbps over 62.5/125 micron Multimode

NOTE

Note

symbol. Calls the reader’s attention to any item of

information that may be of special importance.

TIP

Tip

symbol. Conveys helpful hints concerning procedures or

actions.

!

CAUTION

Caution

symbol. Contains information essential to avoid

damage to the equipment.

Warning

symbol. Warns against an action that could result in

equipment damage, personal injury or death.

Chapter 1:

Introduction

Page 1-4 Fast Network 100 User Guide

(MM) ﬁber. The FN100 is available in the four conﬁgurations shown

below.

Figure 1-1 8 TX Ports and 1 Redundant FX (Fiber Optic) Port (FN100-8)

Figure 1-2 16 TX Ports and 2 Redundant FX Ports (FN100-16)

Figure 1-3 8 FX Ports (FN100-8FX)

Figure 1-4 16 FX Ports (FN100-16FX)

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Overview

Fast Network 100 User Guide Page 1-5

The FN100 features the following:

• Supports 10BASE-T, 100BASE-TX, and 100BASE-FX standards.

• Supports IEEE 802.3u Auto-Negotiation for 10BASE-T and

100BASE-TX connections.

• Provides full store and forward switching functionality.

• Supports trunking for combining up to 8 links for a total bandwidth of

800 Mbps.

• Lets you deﬁne virtual workgroups to optimize network trafﬁc.

• Allows you to conﬁgure the FN100 into four virtual switches.

• Supports 48-bit IEEE 802 MAC addressing.

• Maintains a learning database of up to 8192 MAC-address entries.

• Implements the Spanning Tree protocol (802.1d).

• Comes with factory-set defaults for plug-and-play capability.

In addition, the FN100 offers features that can help you manage and

maintain your network, such as:

• Conﬁguration and management using the Simple Network

Management Protocol (SNMP) with either an in-band or out-of-band

connection.

• Cabletron Systems Local Console Manager (LCM).

• Protection against multicast storms.

The FN100 contains full store-and-forward functionality and is protocol

transparent. This allows the FN100 to bridge different types of network

trafﬁc, regardless of the network protocol. The FN100 supports over 8000

MAC addresses, with constant learning and aging of the entries associated

with each port.

The FN100 supports IEEE 802.1(d) Spanning Tree that allows the design

of fully redundant Fast Ethernet topologies. In addition, the FN100

supports Cabletron Systems port trunking feature allowing a number of

parallel links to provide a higher aggregate bandwidth.

Chapter 1:

Introduction

Page 1-6 Fast Network 100 User Guide

To dynamically arbitrate between 10 Mbps and 100 Mbps on each port,

the FN100 employs IEEE 802.3u Auto-Negotiation. Auto-Negotiation

allows each 10BASE-T/100BASE-TX port on the FN100 to

self-conﬁgure to 100 Mbps when the device on the other end of the wire is

also capable of self-conﬁguration to 100 Mbps. This is performed

automatically via information exchanged between devices sharing the

same link without management intervention. The FN100 also provides the

ability to disable Auto-Negotiation if desired, locally or through remote

management.The FN100 is fully SNMP compliant for comprehensive

monitoring and control by all popular network management systems.

Finally, the FN100 has LEDs for each port indicating link, transmit

activity, receive activity, collisions, and port speeds (10/100 Mbps).

1.4.1 OSI Compliance

The Open System Interconnection (OSI) Reference Model, developed by

the International Standards Organization (ISO), identiﬁes the levels of

functionality inherent in each of its seven layers. The FN100 operates at

the Media Access Control (MAC) sub-layer of the Data Link layer.

Figure 1-5 shows the OSI Reference Model.

Figure 1-5 OSI Reference Model

Because the FN100 does not process any Network Layer information, it

provides a high level of performance in terms of packet throughput. In

addition, the FN100 does not need to learn network topology, requiring

less programming and conﬁguration time.

6

Presentation

7

5

4

3

2

1

Application

Session

Transport

Network

Data Link

Physical

FN100 operates at Layer 2

FN100 Architecture

Fast Network 100 User Guide Page 1-7

1.5 FN100 ARCHITECTURE

The FN100 is based on an architecture that utilizes a high speed switch

engine coupled with an AMD 29200 RISC processor for management

functions. This architecture provides an efﬁcient mix of optimal

performance and intelligence.

The non-blocking design of the FN100 provides wire-speed ﬁltering and

forwarding rates for all Fast Ethernet ports, allowing the device to keep up

with incoming packets even when the packet rates on all LANs are at the

maximum possible rate.

The high speed scalable switch fabric at the core of the FN100 allows

packets to be forwarded through the FN100 at very high rates with

minimal latency. The switch fabric in the FN100 supports data rates up to

2.56 Gbps - more than enough for sixteen 100 Mbps ports.

The Address Database Engine is used by the FN100 to make ﬁltering and

forwarding decisions. Each time a packet is received, it is placed into

packet memory, analyzed for errors, compared against the MAC address

and ﬁltering entries in the database, and sent to the appropriate destination

port.

1.5.1 Store and Forward Switching

The FN100 is an intelligent Fast Ethernet switch that uses full store and

forward switching. Store and forward switching allows the FN100 to

temporarily store packets until network resources, typically an unused

link, are available for forwarding. This allows for complete error

checking, and limits the amount of time between when a device requests

access to the network and when it is granted permission to transmit. In

addition, full store and forward switching ensures data integrity and

prevents error conditions from being generated throughout the network.

Chapter 1:

Introduction

Page 1-8 Fast Network 100 User Guide

1.5.2 Spanning Tree Algorithm

The FN100 supports the IEEE 802.1d Spanning Tree algorithm. The

Spanning Tree algorithm converts multiple LANs into a “spanning tree”

of networks that prevents bridging loops. This standard deﬁnes a logical

(not physical) network conﬁguration consisting of one extended LAN

without active duplicate paths between spanning tree bridges.

The FN100, along with other IEEE 802.1d Spanning Tree compliant

bridges or switches in the network, dynamically conﬁgure the network

topology into a single Spanning Tree by exchanging Bridge Protocol Data

Units (BPDUs). Typically, each LAN segment is sent one BPDU every

two seconds.

When there are multiple FN100 switches connecting LANs in a loop, the

Spanning Tree algorithm determines which FN100 should forward

packets to the LAN. If there is a cable break or a port failure, the network

topology is automatically reconﬁgured by the Spanning Tree protocol to

create an alternate path to the LAN.

1.5.3 FN100 Bridge Address Table

The FN100 creates and maintains a dynamic database of addresses called

the Bridge Address Table. The FN100 examines every packet to

determine its source address and LAN segment origin. It then compares

the source address and segment information to the entries in the Bridge

Address Table.

If a packet’s address is not already stored in the Bridge Address Table, the

FN100 adds general information including learned address, associated

segment number, trunk group information, and virtual switch information.

Consequently, the FN100 knows the address and associated segment

number the next time it sees that address. By using the information stored

in the Bridge Address Table, the FN100 is able to quickly forward each

packet to the correct LAN segment.

FN100 Architecture

Fast Network 100 User Guide Page 1-9

The FN100 learns addresses from all packets, including data

transmissions and “keep alive” packets (packets sent by an idle station to

let other stations know it is present and functional). When devices are

added to the network, removed from it, or relocated, you do not have to

reconﬁgure the FN100. The FN100 automatically learns new device

addresses, and recognizes when a previously used address is missing, or

when a device has been moved to a new LAN segment.

An address stored in the Bridge Address Table is discarded if there is no

subsequent activity from that address after a conﬁgured length of time

(ﬁve minutes by default). This aging process ensures that the Bridge

Address Table is continually updated.

Each dynamic entry includes:

• An Ethernet MAC address

• A single port number of the LAN on which the address resides

• Trunk group information

• Virtual switch information

The FN100 stores over 8,000 dynamic (learned) entries in its Bridge

Address Table.

Chapter 1:

Introduction

Page 1-10 Fast Network 100 User Guide

1.6 FN100 APPLICATIONS

The FN100 provides the network designer with complete ﬂexibility and

has many applications including:

• Server farms

• High-performance workgroups

• Backbones

1.6.1 Server Farms

Figure 1-6 Using the FN100 to Create Server Farms

As shown in Figure 1-6, the FN100 replaces conventional Ethernet

10BASE-T hubs and switches to provide each ﬁleserver a dedicated 100

Mbps pipe. The increased bandwidth of switched Fast Ethernet allows the

FN100 to instantly multiply the available bandwidth, virtually eliminating

all collisions and providing a means of dramatically increasing the

bandwidth where needed most - at the ﬁleservers.

Fast Ethernet

Server Farm

FN100

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Cabletron Systems FAST NETWORK 100, FN100, FN100-16, FN100-16FX, FN100-8, FN100-8FX User manual

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