Cabletron Systems STHI User Manual

STHI

INTELLIGENT

TOKEN RING STACKABLE HUB

USER’S GUIDE

CABLETRON SYSTEMS, P. O. Box 5005 Rochester, NH 03866-5005

NOTICE

per

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.

© Copyright May, 1995 by:
Cabletron Systems, Inc.
P.O. Box 5005, Rochester, NH 038666-5005

All Rights Reserved

Printed in the United States of America

Order Number: 9031390 May, 1995

SPECTRUM, LANVIEW, Remote LANVIEW

trademarks of Cabletron Systems, Inc.

, and

HubSTACK

, STH, STHI, are

1

i960 is a registered trademark of Intel Corporation.

DEC and VT100

CompuServe

Windows

are trademarks of Digital Equipment Corporation.

is a registered trademark of CompuServe, Inc.

is a registered trademark of Microsoft Corporation.

Printed On

Recycled Pa

iii

NOTICE

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.

2

3

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.

iv

4

NOTICE

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.
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.

You may not reverse engineer, decompile, or

EXCLUSION OF WARRANTY

AND DISCLAIMER OF LIABILITY

1. EXCLUSION OF WARRANTY.
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 EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO IMPLIED WARRANTIES
OF MERCHANTABLITY 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
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
WARRANTEES IN SOME INSTANCES THE ABOVE LIMITATIONS AND
EXCLUSIONS MAY NOT APPLY TO YOU.

Except as may be specifically provided by

. IN NO EVENT

5

6

v

NOTICE

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 03866

7

vi

CONTENTS

CHAPTER 1 Introduction

1.1 Contents of This Manual. . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1

1.2 STHI Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-1

1.2.1 LANVIEW LEDs . . . . . . . . . . . . . . . . . . . . . . . . . .1-2

1.2.2 TCU Ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-3

1.2.3 RI & RO Ports. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4

1.2.4 Hub-By-Hub Bypass Control . . . . . . . . . . . . . . . . . 1-5

1.2.5 Automatic Beacon Recovery Process. . . . . . . . . . .1-5

1.2.6 Support for Passive MAU Workgroups . . . . . . . . .1-5

1.2.7 Flash Downloads. . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6

1.2.8 IP Address Discovery . . . . . . . . . . . . . . . . . . . . . . . 1-6

1.2.9 Local Management . . . . . . . . . . . . . . . . . . . . . . . . .1-8

1.2.10 Remote Network Management Capabilities. . . . . .1-8

1.3 Related Manuals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-8

1.4 Getting Help . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-8

CHAPTER 2 Requirements & Specifications

2.1 General Networking Considerations. . . . . . . . . . . . . . . . . .2-1

2.2 Operating Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . .2-3

2.2.1 Hubstack Interconnect Cables. . . . . . . . . . . . . . . . .2-3

2.2.2 TCU and COM Ports . . . . . . . . . . . . . . . . . . . . . . . 2-3

2.2.3 Supported MIB Groups. . . . . . . . . . . . . . . . . . . . . .2-5

2.2.4 Ring Speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5

2.2.5 Ring Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-6

2.2.6 Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-6

2.2.7 Computing Hardware . . . . . . . . . . . . . . . . . . . . . . .2-7

2.2.8 Environmental Requirements . . . . . . . . . . . . . . . . .2-7

2.2.9 Physical Specifications . . . . . . . . . . . . . . . . . . . . . .2-7

CHAPTER 3 Installation

3.1 Installing the STHI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1

3.1.1 Unpacking the STHI. . . . . . . . . . . . . . . . . . . . . . . .3-1

3.1.2 Stacking the STHI. . . . . . . . . . . . . . . . . . . . . . . . . .3-2

3.1.3 Attaching the Strain Relief Bracket . . . . . . . . . . . .3-2

vii

CONTENTS

3.1.4 Rack-Mounting the STHI . . . . . . . . . . . . . . . . . . . . 3-2

3.1.5 Wall-Mounting the STHI . . . . . . . . . . . . . . . . . . . .3-3

3.1.6 Free-Standing Installations . . . . . . . . . . . . . . . . . . .3-5

3.1.7 Connecting the STHI to the Power Source. . . . . . . 3-6

3.2 TPIM Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-6

3.3 Finishing the Installation. . . . . . . . . . . . . . . . . . . . . . . . . . .3-6

CHAPTER 4 Troubleshooting

4.1 LANVIEW LED Signals . . . . . . . . . . . . . . . . . . . . . . . . . .4-1

4.2 Trouble Resolution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-2

4.3 The Reset Button. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-3

4.4 NVRAM Reset Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4

CHAPTER 5 Local Management

5.1 Accessing LM. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1

5.1.1 Dumb Terminal Configuration . . . . . . . . . . . . . . . . 5-2

5.1.2 Console Cable Configuration . . . . . . . . . . . . . . . . . 5-3

5.1.3 Entering LM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-3

5.2 Using LM Screens. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-4

5.2.1 Working with LM Screens . . . . . . . . . . . . . . . . . . .5-4

5.2.2 Screen Hierarchy. . . . . . . . . . . . . . . . . . . . . . . . . . . 5-6

5.2.3 Screen Introductions . . . . . . . . . . . . . . . . . . . . . . . .5-6

5.3 The System Level Screen . . . . . . . . . . . . . . . . . . . . . . . . . .5-8

5.3.1 System Date and System Time. . . . . . . . . . . . . . . .5-8

5.3.2 IP Address. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-8

5.3.3 Subnet Mask . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-9

5.3.4 Enable IP Address Discovery . . . . . . . . . . . . . . . . .5-9

5.3.5 Enable Beacon Recovery . . . . . . . . . . . . . . . . . . .5-10

5.3.6 MAC Address . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-11

5.3.7 Locally Administered Address . . . . . . . . . . . . . . . 5-11

5.4 The SNMP Community Names Screen . . . . . . . . . . . . . .5-11

5.4.1 Community Name. . . . . . . . . . . . . . . . . . . . . . . . .5-12

5.4.2 Access Policy . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-12

5.5 The SNMP Traps Screen . . . . . . . . . . . . . . . . . . . . . . . . . 5-13

viii

CONTENTS

5.5.1 Trap Destination . . . . . . . . . . . . . . . . . . . . . . . . . .5-13

5.5.2 Trap Community Name . . . . . . . . . . . . . . . . . . . .5-13

5.5.3 Enable Traps . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-13

5.6 The Chassis Status View Screen. . . . . . . . . . . . . . . . . . . .5-14

5.6.1 The Screen Mode Screen Command. . . . . . . . . . .5-14

5.6.2 Multiplexer Configuration Fields . . . . . . . . . . . . . 5-15

5.6.3 Port Configuration Fields . . . . . . . . . . . . . . . . . . . 5-16

5.6.4 NEXT and PREVIOUS. . . . . . . . . . . . . . . . . . . . .5-20

5.6.5 ENABLE ALL PORTS. . . . . . . . . . . . . . . . . . . . .5-20

5.6.6 REFRESH. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-20

5.7 The Component Status Screen . . . . . . . . . . . . . . . . . . . . . 5-20

5.8 The Device Statistics Screen. . . . . . . . . . . . . . . . . . . . . . . 5-21

5.8.1 Screen Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-22

5.8.2 REFRESH 3SEC. . . . . . . . . . . . . . . . . . . . . . . . . . 5-22

5.8.3 General Counter Fields (Group 1) . . . . . . . . . . . .5-23

5.8.4 Ring Information Fields (Group 2). . . . . . . . . . . . 5-23

5.8.5 Isolating Errors Fields (Group 3) . . . . . . . . . . . . .5-25

5.8.6 Non-Isolating Errors (Group 4) . . . . . . . . . . . . . . 5-26

5.9 The SNMP Tool Screen . . . . . . . . . . . . . . . . . . . . . . . . . . 5-27

5.9.1 Community Name. . . . . . . . . . . . . . . . . . . . . . . . .5-28

5.9.2 OID Prepend . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-28

5.9.3 GET. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-28

5.9.4 GETNEXT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-29

5.9.5 STEP. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-29

5.9.6 WALK. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-30

5.9.7 CYCLES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-30

5.9.8 RECALL-OID. . . . . . . . . . . . . . . . . . . . . . . . . . . .5-30

5.9.9 SET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-30

5.9.10 REPEAT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-31

5.9.11 Firmware Image Downloads. . . . . . . . . . . . . . . . .5-31

Appendix A TPIM Specifications

A.1 Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1

A.2 Twisted Pair TPIM Pinouts. . . . . . . . . . . . . . . . . . . . . . . . A-1

A.3 Fiber Optic TPIM Specifications . . . . . . . . . . . . . . . . . . . A-2

ix

CONTENTS

A.3.1 TPIM-F2 for Multimode Fiber . . . . . . . . . . . . . . . A-3

A.3.2 TPIM-F3 for Single Mode Fiber. . . . . . . . . . . . . . A-4

Appendix B Media Specifications

B.1 Unshielded Twisted Pair (UTP) . . . . . . . . . . . . . . . . . . . . .B-1

B.1.1 UTP Cable Categories. . . . . . . . . . . . . . . . . . . . . . .B-1

B.1.2 UTP Lobe Lengths . . . . . . . . . . . . . . . . . . . . . . . . .B-2

B.2 Shielded Twisted Pair (STP). . . . . . . . . . . . . . . . . . . . . . . .B-3

B.2.1 STP Cable Categories. . . . . . . . . . . . . . . . . . . . . . .B-3

B.2.2 STP Lobe Lengths. . . . . . . . . . . . . . . . . . . . . . . . . .B-4

B.2.3 Mixed STP Cable Types. . . . . . . . . . . . . . . . . . . . .B-4

B.3 Single Mode and Multimode Fiber Optic Cabling . . . . . . .B-5

x

CHAPTER 1

Introduction

Welcome to the Cabletron Systems

Ring Hub User’s Guide

understanding of the features and capabilities of the STHI. A general
knowledge of IEEE 802.5 Token Ring communications networks and their
physical layer components will be helpful.

. Please read through this manual to gain an

STHI Intelligent Stackable Token

1.1 Contents of This Manual

Chapter 1,
STHI features, and offers leads to further information.

Chapter 2,
requirements, network guidelines, and STHI operating specifications.

Chapter 3,
making network connections.

Chapter 4,
system to troubleshoot network problems.

Chapter 5,
Management application.

Introduction

Requirements & Specifications

Installation

Troubleshooting

Local Management

, outlines the contents of this manual, describes

, contains instructions for installing the STHI and

, describes how to use the LANVIEW LED

, describes how to use the Local

, describes installation

1.2 STHI Overview

The STHI is an SNMP compliant intelligent hub that provides basic
management functionality including port and station control, statistical
error and trap tracking, and enhanced beacon recovery for a Token Ring
LAN. Its front panel TCU (Trunk Connector Unit) ports allow for network
connections to either active stations or passive Multi-Station Access Units
(MAUs) while its TPIM (Token Ring Port Interface Module) ports allow
for ring expansions across a variety of media. Its rear panel HubSTACK
ports provide for ring expansion through connections to multiple STH
non-intelligent hubs. See Figure 1-1.

Page 1-1

STHI Overview

WITH

WITH

LANVIEW®

LANVIEW

CPU

16 Mb/s

®

24X 23X 22X 21X 20X 19X

ACT

MGMT

RO

12X 11X 10X 9X 8X 7X

18X 17X 16X 15X 14X 13X

6X 5X 4X 3X 2X 1X

STACK 3STACK 2 STACK 5STACK 4

RI

HubSTACK

STHI-24

16M4M

SPEED

STHI-24

TOKEN RING HUB

SUPPORTING 100 OHM UTP CABLE

RESET

COM

TOKEN RING HUB

Figure 1-1. Front and Back Views of the STHI-24

The STHI may be installed as a fully managed stand-alone device, or it
may be stacked with up to four STH hubs, each of which adds 12 or 24
TCU ports to the LAN, bringing the total count to a maximum of 120
managed TCU ports in the stack. The STHI serves as the logical “top” of
the stack and provides full frame and error statistics for the managed ring.

The STHI fully conforms to IEEE 802.5 Token Ring specifications for
connectivity to Token Ring equipment and offers the following Token
Ring enhancement features:

• Local Management, a user interface for management control;

• Cabletron Systems’ Automatic Beacon Recovery Process (ABRP);

• Multiple Ring Out connectivity for Passive MAU workgroups;

• automatic speed fault protection;

• active filtering,

equalizing, and amplify

ing circuitry;

• and LANVIEW LEDs for “at-a-glance” diagnostic monitoring.

1.2.1 LANVIEW LEDs

Cabletron Systems’ LANVIEW status monitoring and diagnostics system
is an array of LEDs which helps users to diagnose power failures,
beaconing conditions, cable faults, and connection problems. Refer to
Section 4.1,

Page 1-2

LANVIEW LED Signals

, for more detail.

STHI Overview

1.2.2 TCU Ports

The four STHI models are functionally identical with the exception of the
number and type of network ports they offer:

Table 1-1. TCUs and Media Types per Model

STHI-22 12 unshielded RJ45 ports
STHI-24 24 unshielded RJ45 ports
STHI-42 12 shielded RJ45 ports
STHI-44 24 shielded RJ45 ports

Each STHI is equipped with TCU ports fitted with female RJ45 modular
connector jacks to support the attachment of either STP (shielded twisted
pair) or UTP (unshielded twisted pair) cabling with RJ45 connector plugs.
Models that support STP cabling use RJ45 connectors that provide a
grounded connection for the cabling shield. See Section 2.2.2,

COM Ports

, for pinouts.

TCU and

Lobe Port and Multiple Ring Out Port Configurations

Each TCU port on the STHI is internally defaulted to operate as a lobe
interface to support the insertion of a Token Ring station into a ring.
However, each TCU port may also be reconfigured via the Local
Management (LM) application (see Section 5.6.3,

Fields

) to function as a Ring Out port which will support connections to

Port Configuration

non-intelligent, passive MAU (Multi-Station Access Unit) workgroups.

Refer also to Section 1.2.6,

Support for Passive MAU Workgroups

.

Ring Speed Fault Protection

STHI hubs also provide Ring Speed Fault Protection on each TCU port to
protect against beaconing conditions caused by stations inserting at the
wrong ring speed. If a ring speed mismatch is detected, the STHI blocks
the port to keep the misconfigured station isolated from the ring and
provides a simple visible LED signal (blinking red at the port’s LED) to
indicate that Ring Speed Fault Protection is blocking the port. The port
remains blocked until the ring speed mismatch condition is removed or
resolved.

Page 1-3

1

2

STHI Overview

Active Circuitry

On each TCU port, STHI hubs provide active circuitry which filters,
equalizes, and amplifies all received signals before transmitting them to
the next point on the ring. The result is enhanced signal integrity and
extended maximum station lobe cable distances.

Daughter Board Upgrade Kit

The following daughter board upgrade kits may be used to expand STHI
hubs from 12 to 24 TCU ports:

• TR-UTP-UGKT for STHI-22.

• TR-STP-UGKT for STHI-42.

1.2.3 RI & RO Ports

The STHI incorporates a pair of RI/RO port sockets for Token Ring Port
Interface Modules (TPIMs). This Ring In / Ring Out port pair allows for
the expansion of the main ring to other hubs. Refer to Section 5.6.3,

Configuration Fields

, Subsection

RING OUT ENABLE Mode

Port

, for the

procedure to enable RI/RO ports.

Essentially, TPIMs are media adapters which enable their host modules to
expand their network connections to other media types. The TPIM models
listed in Table 1-2 are produced by Cabletron Systems and may be
installed in the RI/RO port sockets on the STHI. Refer to Section 3.1,

Installing the STHI

, for installation instructions.

3

4

Table 1-2. TPIMs, Supported Media, and Connectors

TPIM Media Type Connector

TPIM-T1 Shielded Twisted Pair DB9
TPIM-T2 Unshielded Twisted Pair RJ45
TPIM-T4 Shielded Twisted Pair RJ45
TPIM-F2 Multimode Fiber ST
TPIM-F3 Single Mode Fiber ST

Page 1-4

STHI Overview

1.2.4 Hub-By-Hub Bypass Control

Unless otherwise configured by a user, all hubs in an STH/STHI stack are
interconnected to form a continuous Token Ring. Through Local
Management, however, each hub may be individually bypassed from the
continuous ring to form its own isolated ring which does not exchange
data with the other hubs.

If an STH is bypassed from the main ring, the STH module will not receive
data-dependent services such as statistical tracking and beacon recovery,
but other physical control functions such as port configuration remain
unaffected. If the STHI is bypassed, only its TCUs are actually bypassed
from the stack’s common ring: TPIM Ring ports and management systems
maintain their connection to the stack’s common ring.

Refer to Section 5.6.2,

Multiplexer Configuration Fields

, for instructions

regarding bypass control.

1.2.5 Automatic Beacon Recovery Process

To guard the network against operational interruptions due to beaconing
conditions, the STHI protects itself and its attached STH hubs with
Cabletron Systems’ advanced Automatic Beacon Recovery Process. ABRP
engages more quickly and is able to treat conditions beyond the scope of
the IEEE standard beacon recovery process. The STHI automatically
partitions problematic lobes from the ring, allowing the rest of the ring to
continue operating. The hub checks partitioned Ring In/Out ports
periodically and re-enables them automatically if they have recovered;
partitioned TCU ports remain disabled until re-enabled by a user.

1.2.6 Support for Passive MAU Workgroups

By default, each TCU port is configured to its STN (station) setting to
support lobe connections to stations. Whereas a station signals a TCU to
open its interface by providing phantom current down its lobe cable, a
passive Multi-Station Access Unit cannot provide phantom current. To
allow for MAU connections, the user may reconfigure TCU ports via Local
Management to function in Ring Out mode. A TCU port in Ring Out mode
looks for the presence of data bits, rather than phantom current, to
determine link status. Refer to Section 5.6.3,
Subsection

RING OUT ENABLE Mode

Port Configuration Fields

, for configuration instructions.

,

Page 1-5

STHI Overview

Improved Protection from Beaconing

By utilizing multiple Ring Out TCU ports, users can provide enhanced
reliability for existing networks which use passive MAUs because Ring
Out TCU ports allow for the separate attachment of each MAU. Rather
than daisy-chaining MAUs together as a single entity and risking their
collective isolation in case of beaconing, the user can now attach each
MAU individually, reducing the number of MAU ports that are at risk;
ABRP is able to bypass individual Ring Out-to-MAU connections on an
individual basis, leaving other workgroups unaffected. See Figure 1-2.

NOTE

The Ring Out TCU configuration does not provide for the
MAU’s redundant connection to the ring. To achieve dual
attachment to a MAU, use the Ring In and Ring Out TPIM
ports.

1.2.7 Flash Downloads

New and updated firmware may be downloaded into the STHI hub’s
Flash EPROMs. This process may be executed by Cabletron’s Remote
LANVIEW/Windows, version 3.0 or later, or by any device using BOOTP
or TFTP protocols. Refer to Section 5.9.11,

Firmware Image Downloads

for download instructions.

1.2.8 IP Address Discovery

1

,

The STHI supports IP Address Discovery. Through a BootP server (a
network device that holds a user-defined list of MAC addresses and
corresponding IP addresses), network managers may attribute an IP
address to any known MAC address. When the STHI is powered up
without an IP address and IP Address Discovery is enabled, it issues
BootP requests at user-set intervals, essentially asking “does anybody
know my name?” If the BootP server recognizes the MAC address, it tells
the STHI what IP address has been attributed to it. If no BootP sever
responds after 500 request cycles, the STHI automatically boots from its
own FLASH memory and remains without an IP address until a user
provides one through the Local Management interface.

Each STHI has on its backplate a sticker which indicates its MAC address.

Page 1-6

STHI Overview

g
t

g
t

g
t

g
t

DAISY-CHAIN MAU CONFIGURATION

When MAUs are daisy-chained,

they are connected as single collective entity.

The entire chain must be bypassed

to isolate the hub from a single beaconing station.

All stations lose connection if beaconing occurs on any station.

Ring

Out

Ring

In

Hub with

Ring

Ring

Ring

Access Units

Multi-Station

Ring

In

In

In

In

(8 Stations)

(8 Stations)

(8 Stations)

(8 Stations)

Ring In / Ring Out

RING OUT TCU MAU CONFIGURATION

When each MAU is individually connected to the STHi hub,

only one MAU must be bypassed

to isolate the hub from a beaconing MAU station.

The stations on that MAU still go down,

but the remaining MAUs and their stations stay operational.

Ring

Out

Ring

Out

Ring

Out

Ring

Out

STHi TCUs

Ring

Ring

Ring

Ring

In

In

In

In

(8 Stations)

(8 Stations)

(8 Stations)

(8 Stations)

Rin
Ou

Rin
Ou

Rin
Ou

Rin
Ou

Access Units

Multi-Station

Figure 1-2. Improved Beacon Recovery Resolution for MAUs

Page 1-7

Related Manuals

1.2.9 Local Management

The STHI hub’s Local Management application displays packet and error
statistics for the entire stack, for each individual device, or for individual
ports, and enables the user to provide management support for the STHI
and all its attached segments.

Users with actual or emulated VT100 dumb terminals may access Local
Management out-of-band via the RJ45 COM port. Refer to Section 5.1 for
connection instructions.

1.2.10 Remote Network Management Capabilities

The STHI may be managed remotely by a variety of SNMP network
management systems including the following from Cabletron Systems:

• Cabletron Systems SPECTRUM

• Cabletron Systems Remote LANVIEW/Windows





• Cabletron Systems Remote LANVIEW for SunNet Manager

1.3 Related Manuals

Use the Cabletron Systems

STH-22/24 /42/44 User’s Guide

to supplement
the procedures and other technical data provided in this manual. The
procedures contained therein are referenced where appropriate, but are
not repeated in this manual.

1.4 Getting Help

To present any questions, comments, or suggestions concerning this
manual or any Cabletron Systems Product, please contact Cabletron
Systems Technical Support:

By phone [phone]

Monday-Friday; 8am - 8pm EST

By CompuServe

By Internet mail [e-mail]

Page 1-8



GO CTRON from any ! prompt

By Fax: [phone]

By BBS: [phone]

By FTP ctron.com (134.141.197.25)

Login:
Password:

anonymous

your email address

By United States Cabletron Systems, Inc.

Postal Service P.O. Box 5005

Rochester, NH 03866-5005

Getting Help

Page 1-9

CHAPTER 2

Requirements & Specifications

This chapter describes network guidelines, power requirements, and
operating specifications for the STHI. Before performing the installation,
read this chapter and confirm that the network meets the requirements
and conditions specified herein. Failure to follow these guidelines may
result in poor network performance.

Refer to Appendix A,

Refer to Appendix B,

TPIM Specifications

Media Specifications

, for TPIM specifications.

, for cable specifications.

2.1 General Networking Considerations

Take care in planning and preparing the cabling and connections for the
network. The susceptibility of the LAN’s cables to crosstalk and noise
determines the network’s error rate, and thus, the efficiency of data
propagation on the network. The quality of the connections, the length of
cables and other conditions of the installation are critical factors in
determining the quality of the network.

All devices connected to the STHI must meet IEEE 802.5 Token Ring
specifications.

Maximum Number of Stations on a Ring

The maximum stack composed of four 24-port STH hubs and one 24-port
STHI offers a total of 120 TCU ports, but the number of ports available on
the LAN may be increased by the use of passive Multi-Station Access
Units (see to Section 1.2.6,
TPIM Ring In / Ring Out connections to other devices (see Section 1.2.3,

RI & RO Ports).

Support for Passive MAU Workgroups) and

1

While there is no recommended limit to the number of TCU ports to be
made available in a stack, the recommended maximum number of stations
to be inserted simultaneously into a single ring is 255 when using STP lobe
cabling and 150 when using UTP cabling anywhere on the ring. If the ring
has been extended through RI/RO connections, consider the number of
ports on ring extensions as well as those in the stack itself.

Page 2-1

General Networking Considerations

Crosstalk 2

Crosstalk is interference caused by signal coupling between different cable
pairs contained within a multi-pair cable bundle. Multi-pair cables should
not be used for UTP lobe cabling. Avoid mixing Token Ring signals with
other applications (voice, etc.) within the same cable.

Noise 3

Noise can be caused by either crosstalk or externally induced impulses.
Outside systems (motors, switching equipment, fluorescent lighting, high
amperage equipment) may produce electrical interference causing noise.
The number and quality of cable connections also contribute considerably
to noise levels. To reduce noise induced errors, it may be necessary to
re-route cabling away from potential noise sources, or to ensure that the
electrical wiring in the area is properly wired and grounded, or to replace
connectors along affected segments.

Temperature

Signal attenuation varies significantly with temperature when
PVC-insulated cable is used. In areas where temperatures exceed 40˚C, it
is strongly recommended that plenum-rated cables be used instead to
ensure that signal attenuation remains within specifications.

Installation Recommendations 5

In addition to complying with the cable specifications presented in
Appendix A, TPIM Specifications, the cabling installation should comply
with the following recommendations to obtain optimum performance
from the network:

• UTP cabling should be free of splices, stubs, or bridged taps.

• Metal troughs, ducts, etc. carrying Token Ring signals should be

properly grounded.

• Cables should be routed away from sources of electrical noise, such as

power lines, fluorescent lights, electric motors, radio interference, and
heavy machinery.

• Token Ring signals should not be routed through UTP cables that exit

a building or which are adjacent to cables either exiting a building or
exposed to lightning strikes and power surges.

4

Page 2-2

Operating Specifications

• UTP cables that contain Token Ring signals should not be
simultaneously used for applications which may impress high
voltages (greater than 5 volts) with sharp rise or fall times, since the
noise coupling from such signals could directly cause errors on the
Token Ring network.

• Where practical, dedicated cable should be used for Token Ring
signals.

• Work area wall plates and outlets used for the Token Ring network
should be clearly labeled as Token Ring network lobe connections.

2.2 Operating Specifications

Cabletron Systems reserves the right to change these specifications
without notice.

2.2.1 Hubstack Interconnect Cables

Cabletron’s HubSTACK Interconnect cables (Part Number 9380141) must
be used when interconnecting STH devices with the STHI.

2.2.2 TCU and COM Ports

The STHI hub’s network ports are female RJ45 connectors. The pinouts
shown in Figure 2-1 are common to all STHI and STH TCU ports.

Cable Shield*

TX+

8

RX-

RX+

7
6
5
4
3
2
1

MALE

RJ45

*Cable Shield
not used
with UTP cabling

TX-

Cable Shield*

Figure 2-1. TCU pinouts

On STHI models -42/-44, each RJ45 connector is encased in a metallic
shield which provides a means of connection for the STP cable shield.

Page 2-3

Operating Specifications

dy

Shield continuity is maintained by contacts within the female RJ45 that
contact the metallic casing of the male RJ45 on the STP lobe cable.

The COM port is a female RJ45 connector supporting EIA RS232C
connections via cables with pinout configurations as specified in Figure
2-2 or Figure 2-3.

RJ45 Plug

18

Female 25 Pin D-Shell

113

25 14

Transmit......Pin 1 .......to ......Pin 3 ......Receive

Receive......Pin 4....... to......Pin 2...... Transmit

Signal Ground......Pin 5....... to......Pin 7...... Signal Ground

Data Carrier Detect......Pin 2....... to......Pin 20......Data Terminal Rea

Data Terminal Ready......Pin 6....... to......Pin 5...... Clear to Send

Figure 2-2. RJ45 to DB25 Connector Pinout

RJ45 Plug

18

Female DB-9

15

96

Transmit..... Pin 1 .......to ......Pin 2 ........Receive

Receive..... Pin 4....... to......Pin 3........ Transmit

Signal Ground..... Pin 5....... to......Pin 5........ Signal Ground

Request to Send..... Pin 7....... to......Pin 7........Ready to Send

Clear to Send..... Pin 8....... to......Pin 8........Clear to Send

Figure 2-3. RJ45 to DB9 Connector Pinout

Page 2-4

Operating Specifications

2.2.3 Supported MIB Groups

The STHI provides access to the following Management Information Base
groups and their respective functionality:

Standard MIBs 1

• MIB-2 (RFC 1231)

Cabletron Enterprise MIBs 2

• Download

• MIB-II Extensions

• Token Ring FNB (Flexible Network Bus)

• DOT 5 Physical & Logical

• Token Ring Station Assignment

• Device

• PIC MIB (Product Information Chip MIB)

• Chassis MIB

2.2.4 Ring Speed

The operating ring speed for the STHI may be set via the Ring Speed
Switch on the front face of the STHI or by MIB commands via the SNMP
Tool screen in Local Management.

The STHI hub’s Ring Speed switch setting is read only at power-up. In
order to change the ring speed via the Ring Speed switch, the user must
first change the switch setting and then reset the STHI (see Section 4.3, The
Reset Button).

MIB commands override the Ring Speed switch setting. Once the switch
setting has been overridden, the MIB command ring speed setting will
remain in effect at all subsequent power-ups as long as the switch setting
is not changed. MIB commands are accessible through the MIB Navigator
screen on the intelligent hub’s Local Management application and
through other SNMP network management software packages including
Cabletron Systems’ Remote LANVIEW

®

/Windows.

The user may cancel the MIB override and regain switch control over the
STHI hub’s ring speed by changing the current switch position and
resetting the STH by the reset button.

Page 2-5

Operating Specifications

NOTE

When cancelling a MIB override, the user may have to reset
twice (as described in the steps below) to actually change
the STHI hub’s ring speed by the switch.

To return to switch control from a MIB-overridden Ring Speed setting:

1. Regain switch control. Regardless of the actual desired ring speed,
the user must toggle the switch out of its current position and then
reset the STHI to put a switch-position change into effect, cancelling
the MIB override.

2. Select the desired ring speed. If the Ring Speed switch setting is not
yet the desired setting (it may now be the same as the setting dictated
by the MIB command), the user must again change the switch setting
and reset the STH to complete the change from the MIB-commanded
speed setting to the desired switch-set speed setting,

2.2.5 Ring Sequence

The ring sequence for the stations on the ring (the order in which stations
are logically arranged on the ring) is determined by the physical location
of each TCU connection, progressing in ascending stack number and port
number order. The sequence is changed each time a station is inserted or
de-inserted from a ring.

To determine the ring sequence, consider only those ports inserted into the
ring. Beginning at the STHI hub’s lowest numbered inserted port, list in
ascending numerical order the number of each inserted port. If STH hubs
have been stacked to the STHI, then continue by listing those inserted in
the STH hub numbered lowest in the stack. Repeatedly move to each next
STH and list the inserted ports in numerical order until all ports inserted
into the ring have been listed. The order is continuous, wrapping directly
from the stack’s last inserted port to the first—from the bottom of the list,
right back to the top.

Hubs that are bypassed from the stack’s common ring must

TIP

not be counted in the common ring sequence; they comprise
their own separate rings with separate ring sequences.

2.2.6 Safety

This equipment is designed in accordance with UL478, UL910, NEC
725-2(b), CSA, IEC, TUV, VDE Class A, and meets FCC Part 15, Class A
limits.

Page 2-6