Digital Equipment VAXstation 2000 Installation and maintenance instructions

Workstations
and Micro VAX 2000
Network Guide
Order Number EK-NETAB-UG-002
digital equipment corporation
maynard, massachusetts

December 1986
October 1987
The information in this document is subject to change without notice and should not be construed as a
commitment by Digital Equipment Corporation.
Digital EquipmentCorporationassumesno responsibility for any errors that may appear in this document.
The software, ifany, described in this document is furnished undera license and maybe usedor copied only
in accordance with the terms of such license. No responsibility is assumedforthe use or reliabUity ofsoftware
or equipment that is not supplied by Digital Equipment Corporation or its affiliatedcompanies.
Copyright ©1986, 1987 by Digital Equipment Corporation.
All Rights Reserved.
The READER'S COMMENTS form on th^ last page of this document requests the user's critital evaluation to
assist in preparing future documentation.
The following are trademarks of Digital Equipment Corporation:
DEBET
MicroVAX UNIBUS
DEC
Microns
ULTRIX-32
DECconnect
PDP ULTRIX-32m
DECmate
P/OS
VAX
DECUS
Professional
VAXcluster
DECwriter Rainbow VAXstation
DEQNA
RSTS
VMS
DEUNA RSX VT
DIBOL
RT
Work Processor
MASSBUS
ThinWire
SDSBDSD
TM
ML-S754

^ Contents
Preface vu
Chapter 1 Overview
What Makes a Network? 1-1
Standard Ethernet 1-1
ThinWire Ethernet 1-1
Unshielded Twisted-Pair Ethernet 1-2
DECnet 1-3
Networking Capabilities of ULTRIX 1-3
Local Area VAXclusters 1-4
Chapter 2 Setting Up the Network
Standard Ethernet 2-1
Basic ThinWire Components 2-2
ThinWire Ethernet Cable 2-3
Connectors and Terminators 2-5
Additional Equipment 2-6
DIGITAL ThinWire Ethernet Multiport Repeater (DEMPR) . . . 2-6
DIGITAL ThinWire Ethernet Station Adapter (DESTA) 2-7
DEBETs — The Ethernet Bridge 2-8
ThinWire Configurations 2-8
DECconnect Approach 2-9
Daisy-chain Approach 2-10
Combined Daisy-chain and DECconnect Approach 2-10
Single Segment Configuration 2-11
Multisegment ThinWire Configuration 2-13
ThinWire Ethernet Rules 2-14
Configurations Symbols 2-14
III

Single Segment ThinWire Ethernet 2-15
Stand-alone DEMPR
2-17 ^
Combined Standard/ThinWire Ethernet LAN 2-18
Stand-alone Cascading DEMPRs
2-19
Stand-alone DELNI with DEMPRs 2-20
Local Bridge 2-21
Disconnecting Stations from ThinWire Ethernet 2-22
Local Area VAXcluster Configuration 2-23
Chapter 3 Installing ThinWire Hardware
Before You Start 3-1
Determining Your Needs 3-1
ThinWire Ethernet Cable 3-1
Connectors 3-1
Barrel Connectors and T-Connectors 3-2
DESTA and Transceiver Cable 3-2
Terminators 3-2
DEMPR 3-2
Estimating Your Needs 3-2
Planning the ThinWire Segment 3-3
Setting the Switch for ThinWire Ethernet 3-4
Connecting to a ThinWire Ethernet Segment 3-4
Connecting VAXstation 2000, Micro VAX 2000, or VAXmate .... 3-5
Connecting a Station with a Transceiver Cable 3-8
Connecting to an Existing ThinWire Network 3-12
How to Install a DEMPR 3-12
Stand-alone DEMPR 3-13
Connecting the DEMPR to Standard Ethernet 3-16
How to Lengthen a ThinWire Segment 3-16
How to Verify Network Installation for a VAXstation 2000 or
MicroVAX 2000 3-17
How to Verify Installation for a VAXmate 3-18
Troubleshooting the ThinWire Segment 3-18
Troubleshooting the DEMPR 3-19
Troubleshooting the DESTA 3-19
IV

Troubleshooting Network Software 3-19
Appendix A Associated Documents
Glossary
Index
Figures
2-1 Settingthe Switch for StandardEthernet 2-1
2-2 Connecting the Intermediary Cable 2-2
2-3 ThinWire Ethernet Cable 2-4
2-4 Connectors 2-5
2-5 DIGITAL ThinWire Ethernet Multiport Repeater (DEMPR). . . 2-6
2-6 DIGITAL ThinWire Ethernet Station Adapter (DESTA) 2-7
2-7 Symbols for Cables 2-8
2-8 DECconnect Method of Wiring 2-9
2-9 Single SegmentConfiguration 2-11
2-10 Connecting
ThinWire Ethernet to Standard Ethernet 2-12
2-11 Multisegment
ThinWire Configuration 2-13
2-12 Symbols for Configurations 2-14
2-13 Single Segment ThinWire Configuration 2-16
2-14 Stand-alone DEMPR with ThinWire Cables 2-17
2-15 DEMPR on Standard Ethernet 2-18
2-16 Stand-alone Cascading DEMPRs 2-19
2-17 Stand-alone DELNI with DEMPRs 2-20
2-18 Local Bridge 2-21
2-19 Disconnecting a Station from
ThinWire Ethernet 2-22
_2-20 Local Area VAXcluster 2-24
3-1 Settingthe Switch for ThinWire Ethernet 3-4
3-2 Connectingthe T-connector to ThinWire 3-5
3-3 Connectinga Terminator to the T-connector 3-6
3-4 Adding a Segment to the T-connector 3-6

3-5 Connecting the T-connector to VAXstation 2000 3-7 _
3-6 Connecting the T-connector to ThinWire 3-8
3-7 Connecting a Terminator to the T-connector 3-9
3-8 Adding a Segment to the T-connector 3-9
3-9 Attaching the T-connector to the DESTA 3-10
3-10
Attaching the Transceiver Cable to the DESTA 3-11
3-11 ThinWire Cables Connected to the DEMPR 3-13
3-12 Attaching aTerminator to a ThinWire Segment 3-14
3-13 Terminator Connected to the DEMPR 3-15
3-14 Connecting Two ThinWire Sections 3-16
Tables
2-1 Ordering Information for ThinWire Ethernet Cables 2-4
3-1 Formto Order ThinWire Equipment 3-3
VI

Preface
This manual describes how to configure and install some simple ThinWire
Ethernet networks for VAXstation 2000, MicroVAX2000, or VAXmate systems.
It doesnot describe all possible configurations, but outlinesthe rulesto follow
when configuring your network with ThinWireEthernet.
Recommended Reading Path
1. VAXstation 2000 Hardware Installation Guide, MicroVAX 2000 Hardware
Installation Guide, or VAXmate System Handbook. You should install your
VAXstation 2000, or VAXmate system before installing ThinWireEthernet.
2. Workstations and MicroVAX 2000 Network Guide, Chapter 2. This chapter
tells you how to configure your network.
3. Workstations and MicroVAX 2000Network Guide, Chapter 3. This chapter
describes how to install ThinWire Ethernet hardware on your system.
A glossary at the end ofthe book explains technical terms usedin this book.
Conventions
The following notices appear throughout this guide:
• Notes — Contain general or supplemental information about a topic.
• Caution — Contain information to prevent disruption of the network.
Convention
Meaning
Bold
Notes, cautions, and warnings are bolded.
Italics
Terms defined in the glossary are italicized the first
time the word appears in the text.
VII

Document Structure
This manual consists of three chapters and an appendix.
•Chapter 1 gives an overview of ThinWire Ethernet, defines networks, and
describes DECnet, ULTRIX networks, and VAXclusters.
• Chapter 2 describes the basic components you will need, some simple
configurations, and the rules for connecting to ThinWire Ethernet.
•Chapter 3 describes how to determine your needs and how to install and
troubleshoot a Thin Wire Ethernet network.
• Theappendixlistsassociated documents that mightbe helpfulin planning
your network.
VIII

^ Chapter 1
Overview
Networks are useful to people who need to work together and share
information but still want the attractive features of their own workstation.
People working cooperatively on a project may need to communicate and
exchange information, share common data bases, share files, or use a mail
system, and yet keep their workstation independent. Networks also allow
you to share devices, suchas laser printers or line printers.
What Makes a Network?
A network is a group of computers connected by communications lines to
share information and resources. You need special network hardware and
software to connect your network. DECnet software enables computers to
form a network.
Standard Ethernet
Ethernet is the DIGITAL local area network. Ethernetnetworks provide rapid
access to data in remote locations, and the high data rate supported by
DIGITAL'S DECnet software makes file transfers practical.
In baseband Ethernet (Standard or ThinWire), a single network cable replaces
the numerous interconnecting cables in traditional data networks. Standard
Ethernet cable is recommended for commimications between floors and
buildings. ThinWire cable is recommended for communications between
workstations, personal computers, and low-end systems in local work areas
on a floor.
ThinWire Ethernet
ThinWire is a networking cabling system and set of products that deliver 10
megabits-per-second Ethernet to the desk, work area, and local area systems
for connection of personal computers, workstations, network servers, and
low-end computing devices. All DIGITAL Ethernet products can connect to
ThinWire offering an alternative wiring approach for low-end, mid-range.
Overview 1—1

and high-end systems and Ethernet servers without any change in network
performance. , ^
ThinWire Ethernet is used in any size environment. It is ideal for a small
stand-alone network in which personal computer and workstation users
share resources, such as prmters and storage devices.
ThmWire works
well as a small- to medium-sized stand-alone local area network (LAN)
in a small business or in a department of a larger organization where
personal computer and workstation users need local resource sharing and
more powerful computing resources. A LAN isa high-speed communications
network that covers a limited geographical area, such as a section of a
building, an entire building, or a cluster of buildings.
Unshielded Twisted-Pair Ethernet
The Unshielded Twisted-Pair Ethernet Adapter delivers 10 megabits-per-
second Ethernet performance to the desktop, work area, and local system
over unshielded twisted-pair building cable.
Unshielded tvdsted-pair adapters connect a single device,
• DESTA with Micro VAX attached
• VAXmate
• VAXstation 2000
•Personal computer with DEPCA, DELUA, or DELQA Ethernet controllers
to the Ethernet network by means of the DIGITAL ThinWire Ethernet
Multiport Repeater (DEMPR). Small stand-alone local area networks, where a
personal computer and workstation usershare limited local resources (printers,
storage devices), can be connected as a subnetwork to large local area and
wide area networks.
Functionally, the office adapter and wiring closet/SER adapter work as a
pair to match the 50-ohm impedance on a ThinWire Ethernet coaxial cable
to the impedance on an unshielded twisted-pair cable. Thus, unshielded
tv«sted-pair building wiring can be used, in addition to ThinWire cable, to
run Ethernet to the desktop.
Unshielded Twisted-PairEthernet Adapters are compatiblewith the ThinWire
Ethernet products and IEEE 802.3 specificationsfor "Medium Attachment Unit
and Baseband Medium Specifications for Type 10 Base 2."
1 —2 Workstations and MicroVAX 2Q00 Network Guide