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Document:	Ethernet Installation Guide Site Survey and Configuration Planning Volume 1
Order Number:	EK-ETHV1-IN
Revision:	003
Pages:	100
Original Filename:

OCR Text

Networks ¢ Communication

Ethernet
Installation Guide
Site Survey and Configuration Planning
Volume
1
Installation and Testing

Volume 2

EK-ETHV1-IN-003

Networks « Communication

Ethernet
Installation Guide

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Site“flé

Digital Equipment Corporation

1st Edition, August 1983
2nd Edition (Rev), November 1984

3rd Edition (Rev), October 1985

The information in this document is subject to change without notice and should not be
construed as a commitment by Digital Equipment Corporation. Digital Equipment

Corporation assumes no responsibility for any errors that may appear in this document.
S

Printed in U.S.A.
S

This document was set on a DIGITAL DECset Integrated Publishing System.
I

Class A Computing Devices:
ARG

Notice: This equipment generates, uses, and may emit radio frequency energy. The
equipment has been type tested and found to comply with the limits for a Class A

computing device pursuant to Subpart J of Part 15 of FCC Rules, which are designed to
provide reasonable protection against such radio frequency interference when operated

in a commercial environment. Operation of this equipment in a residential area may
cause interference in which case the user at his own expense may be required to take
measures to correct the interference.

The following are trademarks of Digital Equipment Corporation:

flflfllflfl
d
L

DEREP
DEUNA

DEC

DECmate
DECnet
DECUS

|
|

Rainbow
RSTS

DIGITAL

RSX

ETHERJACK
LA

UNIBUS
VAX

MASSBUS

DECwriter

VMS

PDP

DELNI

P/OS

Work Processor

Professional

CONTENTS
PREFACE

Yool
vk,

DI DI e

INTRODUCTION

SYSTEM OVERVIEW ..ottt
eeeveeeseetesstessseesssstassaasessasssasanassaans 1-1
PHYSICAL CHANNEL COMPONENTS .................. eteeeeteeeereessreenntera————a——————————_ 1-2
Components and Station EQuipment ...........ccccciiiiiiiiie 1-3
Component Descriptions..................... sueisenssessnasasniatesetennastsnsnnnnnsensisasasestssnsnannanas 1-4

Juol

Soisionnl;

CHAPTER 1

CHAPTER 2

SITE SURVEY

INTRODUCTION ... e eeerrreetbrerabt—————————————— 2-1
MEASUREMENT CONVENTIONS.................. ettt reeeeeeaeeieaeaaen———an———ataaeaaaaaaaanns 2-1
TYPES OF INSTALLATIONS ..ottt ietetieebteaatbeeebeeeeneeeesseeeeraseesiseansranns 2-1
Site Occupancy and SErUCLUTE .......ccoviiieiriieiiieiiie e 2-1
SURVEY PREPARATION ....oooiiiiitiiiiieitieet
ettt easveteeetaestvaeseeseeseaesssseaessssssseannssnes 2-2
Survey Personnel.........coccoeieieniiiiiicniceene e,e,e 2-2
Locating Physical Channel Components...........ccccooeiiiiiiiiiiiiiiiiiiiiceiic
s 2-3
Survey Tools........cc.occ.....e.et e—————e eeeerstasnsinnsessraseasasteeererannnannnne e 2-8
THE SURVEY ..ottt et teretteen———————a———————————————— 2-8
Floor Plan Layout PrOCEAUTE ... vveoeeseoeeeeoeeeeeee e et —————————— 2-9
Survey Considerations ..........cooocveeeerriiiiieeeriiiiiiee
e
aaea e e 2-9
Environmental AIFSPACE .......cooiiiiiiiiiiiiiiiiiee
e e eeereeeeiee e
e s e e e en v aaeaaaans 2-10
Transceiver LOCAtION .....oovvuuieiiiiiiieee
e
e e e e 2-13

Transceiver Drop €Cable ..........ooeiiiiiiiiiiiii e 2-13
Fiber-Optic Cable (BNE25B-XX) ...cooiiiiiiiiiiiiiiiiiciee
e 2-14
SYSTEM GROUND (NETWORK EARTH REFERENCE)...........c..cccccooi 2-16
Measuring Earth Reference (Ground) Characteristics ..........cooceviiiiiininnnnnn. 2-18
System Ground Test TOOIS......cc.occoiiiiriiiiiiiiii
e, e 2-18
Ground Test ProCedUIes.........cceiiiiieiiiiiiiiceiie e 2-20

CONFIGURATION PLANNING
INT RODUCI ION...................................................................................................... 3-1
-

PLLLLLWWNNDNDNN
=

CHAPTER 3

oW
N -

Planmn Guldelmes
Recorded Information
[ransceiver Dro
able Targetin
Coaxial Cable Path Layout
Plan Iteration
1

RAED R I ARRE R AN EER R A BT E R A DD R RET G P A SRRSO

AR DN F N RS NN BB RS A BRI F OB EEE RO

NS BB

TR RO RN LTI SR ERe

vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv R

T R
L R

nnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnn

AAEHE
BB R E RN A BRI BT B AR

odaxla
ables
[ransceivers
lra sceiver Drop Cables
DELNI Configuration
Repeater Configuration
l;lbfif*o tic Cable
*

E TR R ERR AR

H NI FREFREO S NN E B

E B

RR DI RSB R R TEP PRI RO R RN BRI RS E ISR RSB

Bk B RA

B BN

MBl 22 65

n e

28 B0 s 48 6B E 886420

3-5
3-5
3-6
3-7
3-8

3-8
3-11
3-12
3-15
3-15
3-16

T ey R
A A
N
BRB
B
E
S

uuuuuuuu T

BB EFERBR

AN EE SR A

BHE AR E BB N AR DR

RN EA BB R EARE B O TR AR

EF R RD B R E RIS RERABR R B AR SRS A RBE BT RS

AR RN E SR RRE R ELEE R R E DA DR E R

R DEE IR P I EA BB RS AR OB PR AR

DN RSN

R AT BN R AR B DRI RGBT NSRS G

wwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwwww Rl
e R
]

T L
R R R
R

111

RS R R

BHR

R R AR EER

CONTENTS (Cont)
3.4.1
3.4.2

3.5

ingle-Point Groundin
*

Multipoint

fififififififififififififififififififififififi LA AR

SRR

3-18

‘.
.

Groundin

-18
ETHERNET NETWORK SCHEMATICS ..., 3-18

......................................................................

.................

APPENDIX A

ETHERNET PHYSICAL CHANNEL COMPONENTS

ETHERNET PHYSICAL CHANNEL COMPONENTS ..o A-1
COAXIAL CABLE COMPONENTS Lo A-1
Ethernet Coaxial Cables........ooouoiiiiiee e A-1
CONNECLOTS oo
e eettt
aa e A-1
Ethernet HA000 TransCeIVET .....cooeene et A-2
Transceiver Drop Cable ........ccooeveiviiiiiiiiiiiiiieieeeeee, eeeeeeeeeeee
—— A-3
FIBER-OPTIC CABLES .......ccoovveeeeenn.., et
ettt et — e A-4

A.2.1

A22
A.23
A2.4
A3

APPENDIX B
B.1
B.2

B.3

INTRODUCGTION ...ttt B-1
SITE SURVEY PROCEDURES ..........ootieeeeeeeeeeeee
e B-1
CONFIGURATION PLANNING PROCEDURES .........c.ooooiiiioeieeeeeee. B-2

APPENDIX C

SAMPLE NETWORK LOG

APPENDIX D

BLANK SURVEY PLANNING FORM

D.1

D.2

APPENDIX E

DELNI LOCAL NETWORK INTERCONNECT

E.l

INTRODUCGCTION ..o
e e e e et
e e e ee s E-1
GLOBAL MODE ... e ett
aeeee e eera————————a————— E-1
LOCAL MODKE. ..ot et
ee e e e ———————— e E-1

E.2
E.3

~SN

Figure No.

Title

Page

Ethernet Physical Channel Components........... et
ettt aeeeeaa—aaeertr
e aeti———————n———_ 1-3
Coaxial Cable Connectors, Barrel Connectors, and Terminators ..........cccoveveeeeennnn.... 1-5
H4000 Transceiver ........ccocceeeeeviniiieeeeccniieeeee, et
a et e e e e e e e e e nan 1-6
Transceiver Drop Cable Connectors and Etherjack Connection Box (DEXJK)....... 1-7
DIGITAL Local Network Interconnect (DELNI)......ccootvmiiimieieeeeeeeeeeeeeeeeeeeeen, 1-8
Ethernet Repeater (DEREP-AA) ....cooooiiomeeeeeeeeeeeee
eeeeeeeeeeeeeeeee e, 1-9
Typical DEUNA Host Installation ...............ooiviiiiiiooiie e 1-11

FIGURES (Cont)

2-1

2-2
2-3

—

—
—

2-5
2-6
2-7
2-8

2-9

2-10

2-12
2-13

—

€ADIE RACK .. ettt
s e e e e e e ee e e e e et e aan st e e et e e e e s rban e s e e e a s e anrrnes 2-4
Raised-Floor Installation of an Ethernet Physncai Channel Component ................... 2-5
Ethernet Suspended Ceiling Installation .........ccccccciviiiiiiiiiiii 2-6
Transceiver Drop Cable Routed to an Above-Served Station in a
Suspended-Ceiling Installation ............ccccccoiviiiiii 2-7
Typical Above-Ceiling Environmental Axrspace ...................................................... 2-12
Typical Above-Ceiling Nonenvironmental Airspace............coooienininiin. 2-12
Transceiver Drop Cable Length Measurements............cccooeiiiiiiiiii, 2-15
Network Earth Reference System Components..........ooceeiiviiiiiiiiiiiiniinniinnnn, 2-16

2-4

—
£
—

Typical Installation of an Ethernet Physical Channel Component in an Exposed

Model of Multibuilding Ground Loop Current Flow.............. et ———————————————————— 2-19

Test Setup for the Single-Building Network Earth Reference Connection
e 2-21
iieiiite
et
(Voltage and ReESIStANCE) ........oeeiuiiiiriiiiiiiiicii
- Smgle-Bufld1ng Resistances and
Network Earth Reference System

2-11

CondUCtOrs MOGEL........ooiiiiiiiiiieeeee et

3-1

3-2
3-3
3-4
3-5
3-6
3-7
3-8
B-1
B-2
B-3
B-4
B-5

C-1
E-1
E-2

eeeeeeeeees e 2-21

Test Setup for the Actual Multibuilding Gmund Potential Difference .................. 2-22
Network Earth Reference System— Multibuilding Resistances and
Conductors Model........oovieiiiiiiiiiee
e e e ——————— 2-22
Proposed Ethernet Cable Layout in a Typxcal Plant....ccooooeeiiiiiii
e 3-2
Ethernet Component Layout............ccccccciiini.. e teetteeeraeeesaeeeeeeeeesennreennnnans 3-3
Large-Scale Ethernet Configuration............ccccoeiiiiiiininiiiniis v....3-4
Coaxial Cable Installation Bands............coeiieiiiiiiiiiiiiiiiieeeeeee
e, 3-12
Multiple Station Transceiver Drop Cable Adjustment................o.ccoooi, 3-15
Excess Coaxial Cable Coiled to Minimize the Length of the Earthmg
CONMAUCTOT .ttt
aaeeaasaesnesssnnsesanesssssmsssesessmnsetsmseeasesennnes e 3-19
Ethernet Floor Plan Symbols................... SRe
eeeeeeeee ittt aeaeeernn—aaaaes 3-20
Sample Ethernet Schematic ...........ccoocoiiiiiiiiiiii 3-21
Surveyor’s Marked-Up Floor Plan ..., B-4
Initial Station Targeting .................. eeeeeeeeerea———eaeaaeterar——————a eereeeee e ————aaeaaan B-5
Final Station TarEtiNg.......c.occoveereeiiieeieeeieerreerseeeeeereeeseeesieesseeeee
e s B-6
Plotting the Coaxial Cable Pathway and Hardware Locations .......................... B-7
Second Floor Plan Showing Stations, Transceivers, and Transceiver Drop
CABIES. oottt
et e a ettt ea ettt ettt et e e n et e e eneen e s eene e ennens -8
Sample €Cable Tags .....cooveiiiiiiiiiiee e C-3
DELNI Local Network Interconnect (Local Mode).......cccooeivviiiiiiiiieeniiiiiiiiciiieeenn
E-2
Cascaded Standalone DELNI Local Network Interconnect (Local Mode) .............. E-3

SRS

TABLES

—
N—
Aot

— N

> > > > P

———

Title

Page

Ethernet Coaxial Cable Lengths ................... et eaeeeereeeeeeeeeeeraraay——————————eeteeeaenana 1-4
Coaxial Cable CONNECLOT SIZES ......ccvveeriiiiiiieiieceee
e
e e
eee 1-5
Cable Lengths vs Building Application.....................e
———e ———— 3-10
Transceiver Drop Cable APPCAtions.............ooouiiiiiieiieeee
eeeeeeeeeeeee
eeeeeee e, 3-14
Ethernet Coaxial Cable Lengths ...........ccocviiiiiiiiiiiiiiiiee
e
e
eeee A-1
Coaxial Cable ConneCtor SIZES .........ccc.iieeiuiiiiiieieeeeeieeeeee
e
e e e eeeee s A-2
Transceiver Drop Cable Lengths............oooiuiiiiiiiiiiiiie
e, A-3
Dimensions of Drop Cable Connector Heads ............cccoveeiiiiiemeeeiiieeeiieeeeeeeeeeeeannn, A-4

SR,

PREFACE

MANUAL OVERVIEW

The Ethernet Installation Guide provides DIGITAL Field Service personnel, DIGITAL customers,
and/or designated subcontractors with the necessary technical information and surveying and planning
procedures to successfully install and test an Ethernet Local Area Network (LAN).
This guide consists of two volumes:

Volume I Site Survey and Configuration Planning

Chapter 1 — Overview of the system including a discussion of the physical channel components.

Chapter 2 - Survey criteria including measurement conventions, types of installations, survey
tools, and procedures.

Chapter 3 — Planning component and cable routing.
Appendices A through E - Additional information about the physical channel components and
various forms that must be completed during the survey and planning process.
Volume II Installation and Testing

Chapter 1 — Overview of the installation and test procedures.

Chapter 2 - Installation of the Ethernet physical channel components (procedures and
guidelines).

Chapter 3 — Testing procedures to ensure that installed components function as specified.
Chapter 4 - Repair of cables after damage, correction of transceiver taps, and
repair/replacement of transceiver drop cables.

Chapter 5 - Discussion of cable installations in high-rise buildings, and conduit and nonconduit
installation of fiber-optic cables.
ORDERING INFORMATION

The Ethernet Installation Guide is packaged as a two volume set. When ordering, use order number EKETHER-IN.

Vil

RELATED DOCUMENTS

The following is a list of Ethernet documents that should be referred to during
installation, acceptance
testing, and repair of the Ethernet cabling system.

—

EK-DELNI-IN

DELNI Installation/Owner’s Manual

—

EK-DELNI-TD

DELNI Technical Description

EK-DEREP-TM

DEREP Ethernet Repeater Technical Manual

EK-DEREP-IN

DEREP-AA Loca) Ethernet Repeater Installation/ Ou%ner’s

Manual

EK-DERRP-IN

DEREP-RA Remote Ethernet Repeater Installation/Owner’s

EK-ETHER-RM

Ethernet Reference Manual

EK-H4000-TM

H4000 Digital Ethernet Transceiver Technical Manual

EK-H4000-IN

- H4000 Digital Ethernet Transceiver Installation Manual

MP-01369

H4000 Field Maintenance Print Set

EB-22714-18

Introduction to Local ‘Area Networks

DEUNA User’s Guide

EK-DECNA-IN

DECNA Installation Guide

EK-DEQNA-UG

DEQNA User’s Guide

—

EK-DECSA-SP

The Ethernet Communications Server Site Preparation and
Planning Guide
~

)
B

EK-DECSA-IN

The Ethernet Communications Server Installation Guide

AA-XO19A-TK

The DECnet Router Server Installation and Operations Guide

AA-X020A-TK

Terminal Server Installation and Operations Guide

AA-X021A-TK

The User’s Reference Card

Manual

EK-DEUNA-UG

viii

CHAPTER 1
INTRODUCTION

1.1

SYSTEM OVERVIEW

The Ethernet Local Area Network is a data communications system offering optimized, high-speed
communications channels for connecting various information processing equipment. Typically, the area
served by the Ethernet network is limited to a section of a building, an entire building, or a cluster of
buildings.

The Ethernet Local Area Network enables users to share expensive peripheral devices and data bases that
are connected to a single, logical network cable. This eliminates the need for several inter-connecting
cables as found in the more traditional point-to-point networks. In addition, this network may be easily
upgradfid as new systems and additional capabilities are added without disturbing the operation of the
network.

The following list summarizes the Ethernet specifications.

Item

Description

Topology

Branching bus

Medium

Shielded coaxial cable, Manchester encoded digital base-

Data Rate

10 million bits per second (bits/s)

Maximum Separation of Nodes

2.8 km (1.74 mi)

Maximum Number of Nodes
Network Access

Access Control
Data Packet
Preamble

band signaling

1024
Multiaccess — Fairly distributed to all nodes

Carrier Sense, Multiple Access with Collision Detect

(CSMA/CD)

Packet lengths from 64 to 1518 bytes (includes a variable

length data field of 46 to 1500 bytes)

8 bytes (64 bits)

1-1

Rules for configuring the Ethernet network are derived from limits imposed on cable distances between
connections and the number of components connected. To ensure optimum network performance, the
following conditions should be followed.

(Coaxial cable segment

—

Maximum of 500 m (1640.5 ft) in length

499 ohm () terminators

—

Maximum of 100 transceiver connections accepted

Transceivers

SRR

—

Transceivers are attached to the coaxial cable at black bands that occur every 2.5 m (8.2
|
ft)

—

Transceiver drop cables to station length equals 50 m (164.0 ft) maximum (see Note 1)

iy,

Repeaters

A \W‘WM,'

Maximum of two repeaters (DEREP) (see Note 2) allowed between any two nodes

Distance between any two nodes is a maximum of 2800 m (9186.8 ft)

Network cannot exceed 1024 nodes

NOTES
Station controller assemblies such as the
DEUNA controller, provided by Digital Equipment Corporation, use an internal cabinet cable
that produces a loss equivalent to 10 m (32.8 ft)
of transceiver drop cable. In this case, the max-

imum transceiver drop cable length is limited to
40 m (131.2 f¢).

The DEREP repeater has no internal cable
and, therefore, falls within the 50 m (164.0 ft)
maximum distance limitation for interconnections of multiple segments.
SRR,

1.2 PHYSICAL CHANNEL COMPONENTS
During the planning and design phases of the layout, familiarization with Ethernet physical channel
components and configuration specifications is necessary. A description of these components, along with
procedures for assembling them into an integrated network, is covered in the following sections. Ethernet
physical channel components are illustrated in Figure 1-1.
|

(MAX. SEGMENT LENGTH: 500 METERS 1640.5 FT)

(1) BNE2A/B OR BNE2X

(3) H4000 DIGITAL
ETHERNET
TRANSCEIVER

oty
fi?

bet

)

49.9 OHM

TERMINATOR

SECTION

NOTE 1

(TYPICAL)

ETHERNET
COAXIAL CABLE

ittt
B

iSnratateteteletatoto g
i

ETHERJACK

(3) BARREL
TERMINATOR

'CONNECTOR

CONNECTOR

BNE3 ETHERNET

DROP CABLE 6

TRANSCEIVER
osT

TRANSCEIVER

BNE3 ETHERNET

DROP CABLE

(NOTE 2)

NE7
~7N

SYSTEM

ETHERNET

REPEATER

O ererner
gg“"_fi"”“'c“‘“ows

NTROLLER DISTRIBUTION

TO ANOTHER
SEGRENT

PANEL

(DEUNA, DEQNA, OR DECNA)

—

NOTE

THE CIRCLED NUMBERS ARE KEYED TO PARAGRAPHS ON THE FOLLOWING
PAGES

THERE ARE EIGHT PORTS AVAILABLE THAT CAN CONNECT UP TO EIGHT
ADDITIONAL CONTROLLERS

Figure 1-1

Ethernet Physical Channel Components

1.2.1 Components and Station Equipment
Ethernet communications systems consist of:

r
“

Physical channel components — Physical channel components refer to the coaxial cable and the

hardware that directly attaches to it. These components consist of:

—

FEthernet coaxial cables with preinstalled male type N connectors (DIGITAL model
BNE2A for FEP type cables, and BNE2B for PVC type cables).

—

Double-female type N coaxial barrel connectors (DIGITAL model 12-19817-01).
1-3

Female type N coaxial 49.9 Q connector terminators, (DIGITAL model 12-19816-01).

Transceiver (DIGITAL model H4000 transceiver).

—

Transceiver drop cables (BNE3A or BNE3B for PVC type cables, and BNE3C or

BNE3D for FEP type cables. BNE4A and BNE4B
for office cables).

Etherjack connection box (DEXJK).

Digital Equipment Corporation’s Local Network Interconnect (DIGITAL model
DELNI-AA for U.S. version, and DELNI-AB for non-U.S. versions).

—

Ethernet repeaters (DIGITAL model DEREP-AA (Local) or DEREP-RA (Remote) for
U.S. version) and (DEREP-AB (Local) or DEREP-RB (Remote) for non-U.S versions).

Fiber-optic cable (BN25B).

Station equipment — Station equipment refers to DIGITAL computer systems and other devices
that use the Ethernet Communications System.
1.2.2

Component Descriptions

Coaxial Cable - Digital Equipment Corporation’s Ethernet coaxial cable, BNE2A and BNE2B,

are the main transmission medium for the Ethernet Local Area Network (LAN). These cables
are shielded to provide very low signal loss. One or more shorter lengths of cable, called

sections, can be joined together with a coaxial cable barrel connector to make up a cable
segment. Each open end of the coaxial cable segment must be fitted with a 49.9 Q terminator.

The coaxial cable is supplied in four standard lengths that minimize signal reflections. These
lengths are listed in Table 1-1.
Table 1-1

Lengths
Meters/Feet
- 23.4 m (76.8 ft)
70.2 m (230.3 ft)
117.0 m (383.9 ft)

500.0 m (1640.5 ft)

Ethernet Coaxial Cable Lengths

DIGITAL Part Number
FEP
PVC
BNE2A-MA
BNE2A-MB
BNE2A-MC

BNE2B-MA
BNE2B-MB
BNE2B-MC

BNE2A-ME

BNE2B-ME
.

The model BNE2A coaxial cable contains a Teflon® FEP (fluoridated ethylene propylene
copolymer) fluorocarbon insulation and jacket covering. This material is “classified as fire and
smoke only” in accordance with the National Electrical Code (NEC) Article 725-2(b).

The model BNE2B coaxial cable is made with polyvinyl chloride (PVC) insulation and jacket
covering. PVC cables are not approved for installation in environmental airspaces per the
requirements of NEC article 725-2(b).
e

Teflon is a registered trademark of Dupont de Nemours & Co., Inc.

1-4

Annular rings referred to as black bands, are imprinted on the coaxial cable every 2.5 m (8.2

Additional information on the Ethernet coaxial cables may be found in Appendix A.

goom

ft). These black bands indicate where the Ethernet transceivers may be mounted.

is H4056. Dimensions are listed in Table 1-2.

Coaxial Cable Connectors (Figure 1-2) - All coaxial cable sections are prefitted with male type
N connectors crimped onto the cable at each end. Replacement part number for the connectors
Barrel Connectors (12-19817-01) (Figure 1-2) — Used to join various lengths of coaxial cable.
Barrel connectors are double-female type N connectors. Dimensions are listed in Table 1-2.

@ Terminators (12-19816-01) (Figure 1-2) - Incorporates a 49.9 () resistive element. This 49.9

element has been designed to match the average characteristic impedance of the Ethernet
coaxial cable segments to prevent signal reflections from the ends of the cable. A terminator is
required at each end of the cable. Dimensions are listed in Table 1-2.

CONNECTOR

BARREL

END CONNECTOR

(EACH END),

TERMINATOR

COAXIAL CABLE

CONNECTOR

END

CONNECTOR

(EACH END)

(SECTION

TYPICAL)

MKV84-1693

Figure 1-2

Coaxial Cable Connectors, Barrel Connectors, and Terminators
Table 1-2

Coaxial Cable Connector Sizes

Type

Outside

End Connector

2.1 cm (0.83 in)

Terminator

1.9

Connector
Barrel Connector

Diameter
1.9 cm (0.75 in)

Maximum

Length

4.1 cm (1.61 in)

4.6 cm (1.81 in)

3.6 cm (1.41 in)

cm (0.75 in)

physical and electrical
(5) Transceiver - The DIGITAL H4000 Ethernet transceiver provides the (host
systems, servers,
—

interface between the Ethernet coaxial cable and the Ethernet station
repeaters), and Digital Equipment Corporation’s Local Network Interconnect (DELNI). The
transceiver connects directly to the coaxial cable (refer to Figure 1-3). It consists of a small,

addition, the transceiver provides electrical isolation between the coaxial cable and transceiver

rugged, plastic housing that contains the electronics to send and receive encoded signals. In

cables.

1-5

Length
Width
Height
Weight

|
|

27.7 cm
9.5 cm
9.0 cm
1.4 kg

(10.9 in)
(3.7 in)
(3.5 in)
(3.0 lbs)

A maximum of 100 transceivers may be attached to an Ethernet coaxial cable

segment. These

transceivers are installed on the black attachment bands located every 2.5 m (8.2 ft) on the

cable. Installation requires the use of a special DIGITAL transceiver installation kit.

The transceiver is UL approved for installation in environmental airspaces per requiremen
ts of
NEC Article 725-2(b).

[

TRANSCEIVER DROP

CABLE CONNECTOR

MKV85-2715

Figure 1-3

(®

H4000 Transceiver

Transceiver Drop Cable - Each transceiver requires its own transceiver drop cable. This cable

connects the transceiver to the host, system server, repeater, or DELNI interconnect. Station
transceiver drop cable lengths generally do not exceed 40 m (131.2 ft). This cable is also used to
connect hosts and servers to a DELNI interconnect, or to connect DELNI interconnects when

they are cascaded.

There are three types of transceiver drop cables provided by Digital Equipment Corporation.
These cables may be ordered in various lengths and with either straight or right-angle connectors (refer to Figure 1-4). BNE3A, BNE3C, and BNE4A cables have straight connectors;
BNE3B, BNE3D, and BNE4B cables have right-angle connectors. Refer to Appendix A, Table
A-3 for lengths of transceiver drop cables.
A description of the transceiver drop cables is as follows.

BNE3A or BNE3B - This type of cable is made with polyvinyl chloride (PVC) insulation,

These cables are not approved for installation in environmental airspaces as defined by
NEC Article 300-22(c).

BNE3C or BNE3D - This type of cable is made with fluoridated ethylene propylene
copolymer (FEP) insulation. These cables are approved by UL for installation in environmental airspaces and meet the requirements of NEC Article 725-2(b), “classified as fire
and smoke only”.

BNE4A or BNE4B - This type of cable is made with polyvinyl chloride (PVC) insulation.
These cables are not approved for installation in environmental airspaces as defined by
NEC Article 300-22(c). This type of cable is smaller and more flexible and better suited
for the office environment.

NOTE

For planning purposes, 1 m (3.3 ft) of office cable
(BNE4A/B produces the same attenuation as 4 m
(13.1 ft) of BNE3 cable.

ETHERJACK

CONNECTOR
BOX
DEXJK

STRAIGHT

CONNECTOR

TRANSCEIVER
DROP CABLE

RIGHT-ANGLED

CONNECTOR

TRANSCEIVER

CA"

DROP CABLE

CLAMP

TRANSCEIVER DROP

CABLE
MKV84-1695

Figure 1-4

Transceiver Drop Cable Connectors and Etherjack Connection Box (DEXJK)

1-7

DIGITAL Etherjack Connection Box (DEXJK) - A device for mounting cable connectors. It
can be used to:
®
¢

Secure cables along the base of a wall, keeping the cable from the office floor area.
Cover connectors at cable connection points within the office area.

DIGITAL Local Network Interconnect (DELNI) - An eight-station clustering device that is
logically a short piece of coaxial cable and eight H4000 transceivers in a single box. The
DELNI interconnect can connect any device having an Ethernet communications controller
(DEUNA, DEQNA, or DECNA controllers), including the Ethernet communications servers.
Network performance is the same, whether the devices (controllers or servers) connect to a
DELNI interconnect or directly to an H4000 transceiver.
The DELNI interconnect is housed in a small system box (refer to Figure 1-5) and has a selfcontained power supply. The connector panel has eight device ports and a ninth port for
connection to the H4000 transceiver, or another DELNI interconnect when configured in a
cascaded, standalone mode. A switch permits selection of either Local or Global Mode.

The DELNI interconnect has the following dimensions:

Length

43.2 cm

Width
Height

(17.0 in)

17.8 cm
6.4 cm

(7.0 in)
(2.5 in)

The DELNI interconnect requires an ac power source and comes with a 190.5 cm (75.0 in)
power cord.

GLOBAL TRANSCEIVER
PORT (FEMALE

CONNECTOR)

LOCAL DEVICE

PORTS (MALE

MODE SWITCH

CONNECTOR)
MKV84-1696

Figure 1-5

DIGITAL Local Network Interconnect (DELNI)

1-8

Repeater (DEREP-AA/RA) - A standalone, tabletop device used to expand the Ethernet
network to multiple coaxial cable segments. Each repeater can add a branch segment of coaxial
cable up to 500 m (1640.5 ft) long on which an additional 99 transceivers may be installed (one
transceiver is used to make the DEREP connection).

Digital Equipment Corporation has two types of repeaters.

e
e

Local Repeater (DEREP-AA) - Used Within buildings to connect two coaxial cable

segments that are no more than 100 m (328 ft) apart (refer to Figure 1-6).

Remote Repeater (DEREP-RA) - Consists of two repeater halves connected by a fiber-

optic cable that cannot exceed a length of 1000 m (3281 ft), and connects two coaxial
cable segments. The remote repeater contains a powered systems box at each end of the
fiber-optic cable.

{03331

DEREP

MKV84-1697

Figure 1-6

Ethernet Repeater (DEREP-AA)

Repeaters maintain data integrity by repeating and retiming all signals transmitted between the

two coaxial cables. A repeater requires two H4000 transceivers and two separate transceiver

drop cables for connection to the coaxial cable segments.

Fiber-optic cable is required for the interconnection of two units of a DEREP-RA remote
repeater. Up to 1000 m (3281 ft) of cable may be used. Digital Equipment Corporation
presently supplies preterminated duplex fiber-optic cable (both transmit and receive fibers in a
single jacket) in a number of lengths, BNE25B-x. Fiber-optic cables are suited for use inside
buildings where the cables will not be routed through air plenums. It may also be used in

conduits between buildings where the environmental conditions of temperature and humidity do
no exceed the cable specifications. When polling long lengths of fiber-optic cables, or when
installing fiber-optic cables in conduits, a pulling device is required. Refer to Appendix D for
lengths and part numbers.

The DEREP-AA and DEREP-RA repeaters require an ac power source and each comes with a
190.5 cm (75 in) power cord.

DEUNA, DEQNA, and DECNA Controllers - Digital Equipment Corporation has Ethernet

communication controllers for UNIBUS, Q-BUS, and Professional 350 systems. These

lers implement the Ethernet data link layer function and
connections between nodes. These controllers are:

control-

CSMA /CD protocol to provide
‘

DEUNA - Allows VAX and UNIBUS-based PDP-11 computers to be connected to the
Ethernet network.

DEQNA - Allows Q-BUS systems to be connected to the Ethernet network.

DECNA - Allows the Professional 350 computers to be connected to the Ethernet

network.

These controllers are combinations of hardware module boards, distribution panels, and cabling
that is installed in the host system (refer to Figure 1-7). They connect the host system physically
and electrically through either an H4000 transceiver or a DIGITAL Ethernet Local Network
Interconnect (DELNI) using a transceiver drop cable.

1-10

ETHERNET CONTROLLER

TYPICAL DIGITAL

INSTALLED IN THE

ETHERNET

BACKPLANE

COMMUNICATIONS

CONTROLLER

DISTRIBUTION PANEL

soet

TRANSCEIVER

DROP CABLE

MKV84-1698

Figure 1-7

Typical DEUNA Host Installation

1-11

2.1

INTRODUCTION

Careful planning and design of the physical layout of the Ethernet components is required when the
Ethernet Communications System is installed in an existing building, or a building in the design phase or
under construction. To do this, the surveyor must consider such issues as the type of structure, the type of
occupancy, local building codes, fire codes and restrictions, and the Ethernet configuration specifications.
This chapter addresses these areas.

The objectives of this chapter are to help the site surveyor to:

Gather information on building types, structures, and occupancy,

Investigate and report any particulars of building construction that might affect the installation

Use the proper method for determining distances involved,

Provide the system planner with detailed site measurements,

Locate the stations to be connected on the floor plan,

Suggest appropriate placement for physical channel hardware, and

Ensure that ac power is available for any DELNI interconnects or repeaters used.

2.2

of the Ethernet physical channel components,

MEASUREMENT CONVENTIONS

All measurements given in this guide are in metric dimensions: meters (m), centimeters (cm), millimeters
(mm). English equivalents are given after all metric dimensions, such as, 2.5 m (8.2 ft). Metric measurements should be used when surveying or planning an Ethernet installation to eliminate the need to convert
measurements later.

2.3

TYPES OF INSTALLATIONS

2.3.1

Site Occupancy and Structure

Information gathered during the site survey is dependent upon the type of facility being addressed.

A Network Site Requirement Survey is prepared (refer to Appendix D) to obtain information on the:
Network owner

~ Type buildings
Network size requirements
Target completion date

Information to be recorded about the facility should include the following.
®

Network Owner - Record the name of the network owner, address, name of the facility
manager, and so on.

Type Occupancy - Is the building owned or leased by the customer? If leased, are there any
lease restrictions that prohibit installation of coaxial cable, or restric- tions as to how it is
installed?

Type Structure - Investigate and list the various building characteristics, such as: is the facility
a single-floor or multifloor structure? If station equipment will be located on two or more floors,
special attention must be given to how the floors will be penetrated for cable installation.

Component Location - Locate Ethernet components to comply with local codes, network owner
needs, and aesthetic values. The surveyor must evaluate each site to determine the best location
for these components, including:
-

Suspended-ceiling installation of Ethernet coaxial cables and transceivers where the transceiver drop cable is routed to stations on the floor below.

Suspended-ceiling installation of Ethernet coaxial cables and transceivers where the transceiver drop cable is routed to stations on the floor above.

Raised-floor installation of Ethernet coaxial cables and transceivers where the transceiver
drop cable is routed to stations on the floor above.

A detailed example of a site survey (using sample floor plan layouts) for both suspended-ceiling and raisedfloor installation of Ethernet coaxial cable and H4000 transceivers is presented in Appendix B.

2.4 SURVEY PREPARATION
The following sections discuss the personnel required to conduct the survey and location of physical
channel components, and the type of tools needed for the survey.
2.4.1 Survey Personnel
The system planner is the overall coordinator for the Ethernet installation project. The system planner’s
duties are to define the coaxial cable pathway and to specify the required parts and equipment. The
planner also arranges for the actual installation, verifies that the installation adheres to local building
codes, and verifies network configuration.
The facility manager may be able to provide valuable assistance to the surveyor/ planner in the form of
floor plans and consulting services, as well as, knowledge of the locations of power sources, risers, conduits,
environmental airspaces, firewalls, and so on.
The surveyor should ask the facility manager or plant engineer for assistance in obtaining the services of
the following professionals.
®

HVAC (heating, ventilating, and air conditioning) engineer - An HVAC Engineer can properly
examine the facility’s ventilating system to determine if the proposed Ethernet coaxial cable
installation will be routed through an environmental airspace. Also, it may be necessary to
distinguish between various types of airspaces.

Licensed (or appropriately qualified) electrician — A licensed electrician can survey and locate a
suitable ground (network earth reference) point for the Ethernet Communications System.

sizes and space
Before beginning a site survey, the surveyor should become familiar with the physical
already been
have
ts
componen
These
ts.
componen
requirements of the various Ethernet physical channel
the Ethernet
on
ion
informat
al
Addition
1-7.
discussed in Chapter 1 and are shown in Figures 1-1 through
physical channel components may be obtained from Appendix A.

2.4.2 Locating Physical Channel Components

The surveyor should review the various locations that are available for the placement of the Ethernet
physical channel components, with particular emphasis placed on locating and servicing the coaxial cable,
transceivers, and their drop cables.

Installations, in order of preference, are as follows.

In exposed cable racks, where many computers are installed in a laboratory-type environment
(refer to Figure 2-1). Exposed cable racks offer the greatest ease of installation, while at the
same time, providing the greatest support for the coaxial cables and transceivers.

Underneath raised floors, as found in many computer rooms. In many cases, other cabling
already exists in the space beneath the floor. In this type of installation, the transceiver drop
cables are installed through openings in the floor (refer to Figure 2-2).

In suspended ceilings, the coaxial cable and transceivers are located above the ceiling (refer to
Figure 2-3).

If it is necessary to penetrate a firewall, it should be noted on the floor plans.

When Ethernet coaxial cables and transceivers are installed above suspended ceilings, the transceiver drop
cable can be routed either down to the floor below, or up to the floor above.

When the transceiver drop cable is routed down, the cable may be encased in a drop pole to the work floor.

When the transceiver drop cable is routed up, the cable is routed through a hole drilled in the floor above,
and then through a floor service fitting (refer to Figure 2-4).

The coaxial cable and transceiver should be supported every 3 m (9.8 ft) in a suspended ceiling installation.
There are two methods that can be used to suspend the cable and transceivers.
e

The cable and transceiver can be secured to the ceiling rail support hangers.

The cable and transceivers may be supported by “J” hooks.

Figure 2-4 shows the latter method of securing the equipment.

Floor conduits are wireways located within a poured concrete floor. Due to the limited size of these
conduits [typically 10 cm (4 in)], there may not be sufficient clearance for either the coaxial cable or the
transceivers. In addition, the minimum bend radius requirement [20 cm (8 in)] may often be violated. If
this type of installation is undertaken, place the H4000 transceivers external to the conduit for easy access,
and use a DELNI interconnect to connect up to eight stations.

H4000 TRANSCEIVER,

COAXIAL CABLE

_ TRANSCEIVER
DROP CABLE

MKV85-2716

Figure 2-1

Typical Installation of an Ethernet Physical Channel Compo

nent in an Exposed Cable Rack

2-4

CONTROLLER
_ DISTRIBUTION

R
oo

BE5S8eee8e e

a8 R

B e 8 a8

PANEL

H4000 TRANSCEIVER

COAXIAL CABLE
MKV85-2717

Figure 2-2

Raised-Floor Installation of an Ethernet Physical Channel Component

CABLE TIES

J-HOOKS

NOTE

TRANSCEIVERS AND COAXIAL CABLE ARE SUSPENDED O 3 M (1
-

FT) ABOVE CEILING BY J-HOOKS.

h .20pom -L o ?

e.L $omt=Q o s=w 2 gLo @) ‘D

MKV85-2718

218 = o = o
&n oo =14

FLOOR SERVICE
FLOOR SLAB

TRANSCEIVER

|
|

I
|

]

(SECOND FLOOR)

J-HOOKS
(TYPICAL

DROP CABLE

| H4000

| TRANSCEIVER

COAXIAL
CABLE

SUSPENDED
CEILING
(FIRST FLOOR)

MKV85-2719

Figure 2-4 Transceiver Drop Cable Routed to an Above-Served Station in a Suspended-Ceiling
Installation

2-7

2.4.3

Survey Tools

The surveyor should consider using the following tools when conducting a site survey.

RECORDING TOOLS
°

Floor Plans

The facility manager, architect, plant engineer or other source
should be able to provide the floor plans of the site being surveyed. These floor plans should be reproducible (vellum, sepia, or
mylar). These plans are used to locate all Ethernet physical channel components and to record the various cable runs.

Standard Symbols

Ethernet standard symbols, used to mark the floor plan, are
shown in Figure 3-7.
Y,

Worksheets

- Two worksheets are provided to record site data (refer to Appen-

dix D). These worksheets are:

Network Site Requirements Worksheet — Used to record general
site information; that is, location, size of building, construction,
and so on. One sheet should be made out for each floor.

Station Transceiver Drop Cable Worksheet — Used to record
specific information on cable lengths needed in the area of each
installed station.
MEASURING TOOLS
®

Tape Measure

Primary measuring tool. Most measurements will be less than 10
m (32.8 ft).

Measuring Wheel

Used to take measurements on floors as the surveyor walks the
proposed cable route.
NOTE
Metric measuring tools should be used whenever
possible as DIGITAL Ethernet coaxial cables and

transceiver drop cables are supplied in metric

lengths only.

TAPE RECORDING UNIT

A pocket dictation unit can be helpful for noting details of building construction without pausing to make

written notes. These tapes can later be transcribed.

2.5

THE SURVEY

The purpose of the site survey is to provide the system planner with information to help in the selectidn of
the proper Ethernet physical channel components for the proposed network. This is done by:

Determining the type of building construction,

Locating the stations to ensure that they are appropriate for the installation of the various
components, and

Measuring the actual distances at the site.

These measurements and other data are recorded on the floor plans and worksheets.
-

[he following sections discuss the actual procedure for laying out the Ethernet host systems on the floor

plans.

2.5.1 Floor Plan Layout Procedure
This phase deals with the actual layout of the Ethernet physical channel on the floor plan. This floor plan
layout procedure is as follows.

Obtain a scaled floor plan from an appropriate source.

Locate and identify all known components on the floor plan, along with stations, entry points,

risers, building obstructions, and wall penetrations. Use the appropriate symbols (refer to Figure
3-7 to make the correct identifications). Also, include any planned future station locations.

Entry points are where transceiver drop cables enter an area from a concealed location (ceiling
or floor). In suspended ceiling cable installations, the entry point is the nearest riser pole. In
subfloor cable installations, the entry point is a floor service fitting (if minimum bend radius can
be maintained) or a cable access hole in the raised floor itself.
WARNING

Exercise caution when routing coaxial or transceiver

drop cables in environmental airspaces (refer to Sec-

tion 2.5.3).

Environmental airspaces are enclosed areas that

carry ventilating air for building occupants. Only

material approved for installation in such environ-

mental airspaces is to be used.

Fill out the Station Transceiver Drop Cable Worksheet (Appendix D). Use one worksheet space
per station. Measure the riser length and floor run for each station, and record these measurements on the worksheet.

Identify ac power sources for both the DELNI interconnects and repeaters.

Identify the proposed network earth reference point(s) on the floor plan. Only a qualified
electrician should perform the qualification tests as described in Section 2.6. Record the results
of this test on the Network Site Requirements Worksheet (Appendix D).

Submit the marked-up floor plan(s), Station Transceiver Drop Cable Worksheet(s), the Network Site Requirements Worksheet, and estimates for components and contractor services to
the system planner for approval.

2.5.2

Survey Considerations

When a potential coaxial cable pathway is being surveyed, the following should be considered.
-

The proposed pathway should be accessible so that the installer can physically position the cable
and other physical channel components (refer to Section 2.5.4 for transceiver space
requirements).

When surveying
the proposed pathway through several rooms, note all interior walls and any
obstructions encountered. Note especially where the cable penetrates through these walls.

2-9

WA,

NOTE
Information that cannot be noted on the floor plans
or worksheets should be entered in a separate
notebook. This notebook should then be given to the
system planner.
®

If the coaxial cable penetrates a fire-rated wall or floor, note this on a separate sheet of paper
and give it to the system planner. The system planner is responsible for providing any necessary
fire-rated collars.
T—

Record the locations where the coaxial cable can be secured every 3 m to 5 m (9.8 ft to 16.4 ft).

Record on the floor plans any areas where accessibility is inadequate. This information enables
the system planner to avoid locating any transceivers in this area.

Indicate (by shading or cross-hatching) on the floor plan those areas that are considered exposed

pr—

to extreme temperatures, above 50°C (122°F) or below 5°C (41°F), or high humidity (con-

densing atmosphere).
®

Should the proposed coaxial cable installation be in environmental airspaces, this fact must also
be noted on the floor plans by outlining the area in red. Note if the cable installation varies from
room to room.

If the installation of the proposed coaxial cable pathway involves more than one floor of a
building, the following measurements are to be taken and noted on the floor plan.
A5

—

Measure and record the distance between each floor.

—

Record the location(s) of all interfloor risers on the floor plans.

If using conduits, troughs, or cable raceways, make sure that adequate space for the cable and
pulling apparatus is available within the conduit, trough, or cable raceway. Visual inspection of
the location may be necessary.

If the installation of the coaxial cable pathway involves more than one building, the following
measurements are to be taken and noted on the floor plan.

—

Measure and record the actual conduit length between buildings.

—

Indicate on the floor plans the conduit entry points for each building.

2.5.3 Environmental Airspace
Recent changes in the National Electrical Code (NEC) requires that “remoteTM and “signal” cables being

installed inside environmental airspaces unprotected (without using a metal conduit) be approved (listed)
for such installations by a licensed authority or Underwriters’ Laboratories (UL).
As defined by the NEC, Ethernet physical channel cables, both coaxial and transceiver drop cables, are

- considered “signal” cables.

2-10

50558y

NOTE

The NEC is a set of recommendations that many,
but not all, government agencies adopt intact with
the force of law. However, some agencies adopt
stricter requirements, and these requirements supersede the NEC. A local building inspector or licensed
professional engineer can advise the site surveyor on
local codes.

In some Ethernet physical channel cable installations, the coaxial cable, transceiver, and transceiver drop
cables are installed in the space above a suspended ceiling (refer to Figure 2-3). In many such installations,
this above-ceiling space is an environmental airspace that acts as a warm-air return for a building’s airconditioning system. Figure 2-5 shows an above-ceiling environmental airspace, and Figure 2-6 shows an
above-ceiling nonenvironmental airspace.

These warm-air return openings feed into a duct work (plenum) above the suspended ceiling. If there is no
such duct work, then the entire space above the ceiling tiles (of the suspended ceiling) is the environmental
airspace (refer to Figures 2-5 and 2-6). See NEC Article 300-22(c) for a detailed definition.

UL approved cables may be installed in air carrying spaces that are designated as “other environmental
airspaces” (such as the space above suspended ceilings when such spaces are used to carry ventilating air,
heating, and cooling, without the use of ducts).

NOTE

Only UL listed cables and components, tested and
rated specifically for flame and smoke production
[per NEC Article 725-2(b)], can be installed in an
environmental airspace. These NEC guidelines are
subject to approval by local codes.
The following DIGITAL Ethernet components are

UL-listed for installation in environmental airspaces
where local codes permit.

FEthernet FEP coaxial cable, P/N BNE2A-XX

Ethernet FEP transceiver drop cable, P/N

Ethernet transceiver, P/N H4000

BNE3C-XX

BNE3D-XX

DIGITAL PVC transceiver drop cables (ENE3A and BNE3B, BNE4A and BNE4B) and PVC coaxial

cables (BNE2B), are not UL-listed for installation in environmental airspaces. However, they may be used
in nonenvironmental airspace applications. Office or laboratory nonenclosed areas are considered to be
nonenvironmental airspaces.

2-11

ENVIRONMENTAL AIRSPACE

SUPPLY AIR

DUCT

/l/

! i

ENVIRONMENTAL AIRSPACE
SUSPENDED

\ CEILING 7
DIFFUSE
—
R
/
SUPPLY AIRFLOW

B
RETURN

g AIR GRILL

RETURN AIRFLOW

OCCUPIED AREA
TK-10050

Figure 2-5

Typical Above-Ceiling Environmental Airspace

—_

NON ENVIRONMENTAL AIRSPACE

NONENVIRONMENTAL

RETURN AIR

bUCT

AIRSPACE

SUSPENDED 7

)
L)

>7J>

CEILING
o0

[»]

DIFFUSER —

SUPPLY AIRFLOW

—
°

RETURN AIRFLOW

OCCUPIED AREA
TK-10049

Figure 2-6

Typical Above-Ceiling Nonenvironmental Airspace

—

2-12
S AR

Transceiver Location

2.5.4

An H4000 transceiver is attached to the coaxial cable in the vicinity of the proposed station. Certain
conditions must be observed when surveying for the installation of the H4000 transceiver. These conditions

are:

Temperature

The proposed transceiver installation area should be maintained at a

Support Structure

The structure that supports the coaxial cable must also be able to support

temperature of between 5°C and 50°C (41°F to 122°F) in a noncondensing atmosphere.

the transceiver. Each transceiver weighs about 1.36 kg (3.0 lbs). If the

structure cannot support this additional weight, record this information
for the system planner. It may be that cable racks or other supports will be

|
B
-

required.

Clearance
|

Each proposed H4000 transceiver location must have sufficient clearance
to permit transceiver installation. The following clearances are suggested
as minimum clearances for transceiver installation.
.

Length 20 cm (7.9 in) either side of the black attachment bands.

Width 15 cm (5.9 in) on either side of the coaxial cable.

Height 30 cm (11.8 in) above and below the coaxial cable.

‘

2.5.5

If adequate clearance does not exist near the station to be served,

note any areas within 30 m (98.4 ft) that do have the required

clearances. Record this information for the system planner.
Transceiver Drop Cable

|
-

Each transceiver requires its own drop cable that connects the transceiver to the host system, server,
repeater, or DELNI interconnect. Transceiver drop cable lengths generally do not exceed 40 m (131.2 ft).

When surveying for the transceiver drop cable path, the surveyor should check for:

|
-

Adequate pulling clearances to allow the connector head (D-connector) of the transceiver drop

cable to clear various openings, such as the entry point of the riser.

Adequate packing clearances (room for additional cables) within the riser to permit more than
one transceiver drop cable to be installed. Each cable is about 1 cm (0.4 in) in diameter.

Minimum practical bend radius [10 cm (4.0 in)]. Any bend or corner that might require a
sharper bend should be noted on the floor plans for the system planner.

The ability to secure the transceiver drop cable to the Ethernet coaxial cable within 15 cm (6 in)

of the connector on the transceiver. This is to provide strain relief.

The following measurements and notations should be made on the Station Transceiver Drop Cable

Worksheet (refer to Appendix D).
e

Record each station name and number.

2-13

Measure and record the riser length. This is the vertical path length needed to reach from the
station floor to the level plane of the coaxial cable and transceivers.

For suspended ceilings, this is the drop pole length.
For subfloor installation, this is the floor to subfloor distance.
®

Measure and record the riser floor run. This is the horizontal distance that the transceiver drop
cable needs to reach the station after it has left the riser.
I

Measure the possible paths the cable will follow along the floor, including all corners and bends.

Allow approximately 1 m (3.281 ft) for slack.

An example of riser length, riser floor run, and coaxial cable entry point distance is shown in Figure 2-7.

Record on the floor plan:

Station location including the station name and number used on the worksheet.

—

Location of the nearest riser/drop pole with adequate room for the transceiver drop
cable(s).

2.5.6 Fiber-Optic Cable (BNE25B-XX)
It 1s important that the surveyor understand the unique characteristics of the fiber-optic cable, and to

adhere to the fiber-optic cable specifications at all times. If a network owner is to provide their own fiberoptic cable, the specifications will be made available by a DIGITAL Account Manager or the installation
manual that supports the fiber-optic product.

During the site survey, conducting a walk-through (with or without a contractor) or preparing the drawings
for installation, the surveyor should be aware of the following important considerations.
®

Fiber-optic cable is very sensitive to bend radius. Strain relief is difficult to provide for the cable

as it passes through conduits and ducting that are normally suitable for copper cables. Improper
tying of a fiber-optic cable may produce a kink that puts the cable out of specification. Extra
looping is recommended at corners in order to provide for smooth turns, and for inadvertent
pulling of the cable when additional pairs are added to the same conduit.
®

Avoid right-angle bends within a conduit that exceed the fiber-optic cable specifications.

When surveying for vertical cable paths (elevator shafts), ensure that the fiber-optic cable is
accessible and is capable of tie-downs at the interval required in the specification. Free-hanging
cable may result in excessive stress on the fiber-optic elements.

Add 10 mto 20 m (32.8 ft to 65.6 ft) of extra cable at each end of the installation to allow for

the movement of equipment and/or for future maintenance.

2-14

ENTRY
POINT

COAXIAL
CABLE

ENTRY POINT DISTANCE

TRANSCEIVER

pRrop

CABLE

RISER
LENGTH

STATION

RISER FLOOR RUN
MKV85-2720

Figure 2-7

Transceiver Drop Cable Length Measurements

2-15

2.6

SYSTEM GROUND (NETWORK EARTH REFERENCE)

Electrical codes generally require that a system ground be selected and installed to connect the coaxial

cable shield with a reference point for the site’s electrical service system (refer to Figure 2-8). This system
ground consists of:
®

HOBNE,

Network Earth Reference — A metallic connection point, tested and found to be in continuity
with the building’s grounding electrode system.
P

Coaxial Cable Shield Connection Point — A selected barrel connector or terminator used to give
a metallic access to the shield.
Earthing Conductor — A length of wire used to connect the network earth reference to the
coaxial cable shield connection point.

COAXIAL

CABLE
SHIELD

CONNECTION
POINT

—

/- COAXIAL CABLE

GROUND CLAMP

‘

ELECTRICAL

gEmsr\éfrch
EQUIPMENT

EARTHING

METALLIC

ENCLOSURE

CONDUIT

(TYPICAL)

CONDUCTOR

Eé?ggENCE

GROUND

BAR

(TYPICAL)

BONDING

BUSHING

(TYPICAL)

J/
- (q) GP
shigopiuiN:

|[D

GROUNDING
ELECTRODE
SYSTEM

(TYPICAL)

GROUNDING
ELECTRODE

CONDUCTOR

(TYPICAL)

MKV84-1704

Figure 2-8

Network Earth Reference System Components
A

2-16

Additional pieces of hardware (ground clamps, terminals, and so on) may be required to complete the

system ground.

The Ethernet Local Area Network requires a single ground for each coaxial cable segment.

Installation of the Ethernet Local Area Network between two or more buildings using a single coaxial
cable segment requires that a system ground be selected in each building. However, in a multibuilding
installation, it is strongly recommended that remote repeaters be used with fiber-optic cables. In this way,
grounding problems between buildings are avoided.

Use a volt-ohmmeter (VOM) and a long test lead to perform network earth reference qualification tests.
NOTE

A licensed electrician should locate a suitable system
ground (network earth reference) point for each
coaxial cable segment of the Ethernet network. In
certain cases, the ground bus or bar of the electrical
service entrance will be concealed behind an electrical power panel or box.

Where possible, existing earth reference wiring or bonding points should be used. In order of preference
@

these include:

Metallic conduits that are traceable back to the building’s electrical service entrance.

Metallic building structural components that are traceable back to the building’s electrical

service entrance.

In multibuilding configurations, the preferred earth reference point will be the one nearest the interbuild-

ing conduit. A site is considered multibuilding if:

Two structures exist that do not share conductive and structural connections (common structur-

The proposed coaxial cable pathway uses an underground metal conduit to reach stations

al steel).

between the structures.

NOTE

Using a remote repeater (DEREP-RA) with fiberoptic cables simplifies multibuilding installations by
eliminating the possibility of interbuilding grounding
problems.

Ideally, if the interbuilding conduit is a metallic conduit buried in contact with the earth, the ends where
the interbuilding conduit appear back in each building may be selected as the earth reference points within
each building. This selection must be verified by testing.

The network earth reference attaches to the coaxial cable shield at a connector. The surveyor should select
at least two possible network earth reference points in each building to give the system planner flexibility.
Figure 2-8 shows a typical earth reference system.

2-17

2.6.1 Measuring Earth Reference (Ground) Characteristics
The quality of the earth reference should be checked by measuring its electrical

characteristics.

Single Building - Check the continuity of the earth reference to the grounding
electrode

system.

Multibuilding -

Check the continuity of each intrabuilding earth reference. Also, measure
the voltage difference between the two buildings.

These measurements verify that the selected earth reference(s) are at ground potential. In single-buil

ding

installations these tests check that the Ethernet coaxial cable is not placed at
an elevated voltage. In
multibuilding installations these tests ensure that excessive ground loop current
does not flow between
buildings (refer to Figure 2-9).
2.6.2 System Ground Test Tools
Ground system testing requires the following tools.
SINGLE BUILDING

Volt-Ohmmeter - Capable of measuring 0 Vac - 1.0 Vac full scale, with an accuracy of 0.01
Vac (10 mV). Also capable of measuring 3.0 ohms + 0.1 ohm (100 milliohms)
.

Test Lead - The test lead is used to perform the voltage differential
and resistance measurements. The test lead must be capable of extending the network earth reference
to the electrical
service grounding electrode system.

MULTIBUILDING (in addition to the tools needed for single building)
e

Wire, AWG 12 or larger - Stranded wire to be used as a test lead between buildings.

must be able to reach the proposed network earth references in each building

This wire
at the same time.

Clamp-On Style AC Ammeter (Optional) - Capable of measuring 0.1 A (100
milliamps).

2-18

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2-19

2.6.3 Ground Test Procedures
The following are ground test procedures for single-building and multibuilding installations.

SINGLE-BUILDING INSTALLATION
To check the grounding system for a single-building installation, refer to Figures 2-10 and 2-11 and
measure the voltage difference from the proposed network earth reference to the grounding electrode

system.

A voltage of up to 1.0 Vac may be due to RF (radio frequency) pickup on the volt-ohmmeter and is

acceptable.

WARNING
Care should be taken as assumed ground potential
may actually be at dangerously elevated voltages.

If the voltage measured is lower than 1.0 Vac, check continuity using the ohm scale on the volt-ohmmeter.
Be sure to calibrate the meter by shorting the test leads together to zero the meter. The reading should be
less than 2.5 Q.

The 2.5 Q value is based on communications station equipment grounding standards developed by USITA
(United States Independent Telephone Association, Washington, DC).

s—

MULTIBUILDING INSTALLATION

Perform the following steps to check the grounding system for a multibuilding installation (refer to Figures
2-12 and 2-13).
e

First, make intrabuilding voltage and resistance measurements on the selected network earth
references inside each building. Voltage from each proposed network earth reference in each
building must be under 1.0 Vac, and the resistance must be 2.5 Q or less.

RSO

Measure and record the interbuilding voltage once the intrabuilding voltage and resistance are
known.
|

WARNING

Elevated voltages may exist between the two build-

ing earth references. When performing this test,
treat the conductors and probes as if they are at
high voltage.
-

NOTE

There should be no more than a 0.475 Vac difference from the induced reading. Potential differences
in excess of this figure may cause excessive ground
loop current to flow in the coaxial cable shield
between the two buildings (refer to Figure 2-13).

PRI

Excessive interbuilding ground potential difference
- is usually difficult to correct. The advice of a profes-

sional electrical contractor should be sought. A
straightforward alternative is the use of a DEREPRA remote repeater and fiber-optic cable.

2-20

VOLT-OHMMETER

ELECTRICAL

SERVICE ENTRANCE
EQUIPMENT
ENCLOSURE

METALLIC

(TYPICAL)

CONDUIT

(TYPICAL)

" BONDING
BUSHING

(TYPICAL)

‘

—

GROUND
BAR

(TYPICAL)

NETWORK
EARTH

TEST LEAD

;

REFERENCE

GROUND LEAD
-]

GROUNDING

ELECTRODE

ELECTRODE
SYSTEM

CONDUCTOR
(TYPICAL)

(TYPICAL)

MKV84-1705

Figure 2-10 Test Setup for the Single-Building Network Earth Reference Connection (Voltage and
Resistance)

NETWORK

GROUND

CLAMP
RESISTANCE

EARTH

EARTHING

REFERENCE
RESISTANCE

CONDUCTOR
RESISTANCE

GROUNDING

ELECTRODE
RESISTANCE

TEST IS PERFORMED BETWEEN THESE TWO POINTS
(<2.5Q)

Figure 2-11

MKV84-1706

Network Earth Reference System - Single-Building Resistances and Conductors Model

2-21

ity

BUILDING A

BUILDING B
[

NETWORK

”

EARTH

‘

NETWORK
—

EARTH

»1

" REFERENCE

BUILDINGA

LONG

NOTE:

REFERENCE

“*“,‘:ww‘ ~

TEST

LEAD

METER PROBE IS
ATTACHED AT

BUILDING

N S

@3& ,

NOTE: METER PROBE IS AN OPEN
CONNECTION TO NETWORK

BUILDING A.

EARTH REFERENCE

BUILDING B.

Figure 2-12

TK-10072

Test Setup for the Actual Multibuilding Ground Potential Differenc

BUILDING A

BUILDING B

gf‘;%)mc

GROUND

REFERENCE

CLAMP

RESISTANCE

RESISTANCE / RESISTANCE

GROUNDING

EARTHING

ELECTRODE

CONDUCTOR

NETWORK

GROUND
|

INTER-

<@— BUILDING —»
SEGMENT

AN\

EARTH

CLAMP

REFERENCE

RESISTANCE

/ RESISTANCE
EARTHING

GROUNDING

CONDUCTOR

ELECTRODE

RESISTANCE

INTERBUILDING

COAXIAL CABLE

SHIELD
RESISTANCE
TK-10052

Figure 2-13

Network Earth Reference System - Multibuilding Resistances and Conducto

rs Model

2-22

CHAPTER 3

CONFIGURATION PLANNING

3.1 INTRODUCTION
After completing the survey, the next phase is to choose components and plan for installation. This chapter

discusses this phase, called configuration planning, and is organized around four major elements.
Planning the coaxial cable path
Physical channel component configurations
Planning a system ground
Ethernet network schematics

Additional help in this planning phase can be found in Appendix B, where sample floor plans are provided.
At this point in the planning cycle, it is important to consider future expansion of not only the host
network, but the addition of office automation equipment, such as terminal servers and personal computers. When routing coaxial cable, run additional cable through future expansion areas.

Placement of the physical channel components must be carefully planned and marked on a physical

channel floor plan. Two floor plans are required because of the amount of information that needs to be
shown.

The first floor plan should show the placement of the coaxial cable, grounding points, barrel connectors,
and terminators (refer to Figure 3-1). This plan shows the relatively stable backbone components.
The second floor plan should show the placement of H4000 transceivers, transceiver drop cables, DELNI
interconnect, repeaters, and host systems (refer to Figure 3-2).

The first plan, or backbone, is often filed with facility drawings, while the second plan is kept and updated
by the network manager.

The objectives of this chapter are to help the system planner to:
e
e

Incorporate the configuration rules, and
Produce a Network System Plan.

Before determining where to place the various components of the Ethernet physical channel, the system
planner should become familiar with all the hardware and components (refer to Chapter 1 and Appendix
A).

The system planner should
be aware that if all the systems (up to 64 maximum) to be interconnected are

within a 90 m (295.3 ft) radius, then only DELNI interconnects are needed to interconnect the various
systems. This eliminates the need for coaxial cables and transceivers (refer to Appendix E).

The physical channel layout plan starts with the building floor plan. The placement of the coaxial cable,
transceivers, and repeaters are marked on this floor plan along with the placement of the host systems and
SErvers.

3-1

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ETHERNET COAXIAL SEGMENT

374.4 M (1236.0 FT)

COAXIAL CABLE SECTION A

23.4 M

(76.8 FT)

COAXIAL CABLE SECTION B-F

70.2 M

(230.2 FT)

LEGEND:

COAXIAL CABLE

EARTH-NETWORK GROUND =

TERMINATORS ~ ======(T) BARREL CONNECTORS

i
MKV84-1707

Figure 3-1

Proposed Ethernet Cable Layout in a Typical Plant

3-2

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MKV84-1708

Figure 3-2

Ethernet Component Layout

3-3

3.2 PLANNING THE COAXIAL CABLE PATH
The coaxial cable is the backbone of the Ethernet Local Area Network. A coaxial
cable segment can be a
maximum of 500 m (1640.5 ft) long and can consist of shorter cable sections joined by
barrel connectors.
Each segment must have terminators installed at each end, and the overall segment must
connect to the
earth network ground (refer to Figure 3-1). Larger areas can be covered by multiple segments
through the
use of repeaters.

Carefully plan where to run the coaxial cable and where to use repeaters to connect branching
segments
(refer to Figure 3-3).
A

—{]]
SEGMENT 1

N~ooE

[]}—

] REPEATER E:l
LINK 1 f\

(=D

E:
]

J
|

N J

SEGMENT 3

COAXIAL

CABLE

]

—J

REMOTE —>
REPEATER

e B

—

FIBER-OPTIC

POINT-TO-POINT

]
SEGMENT4 [

—
|
LINK 2

]

F—|] SEGMENT
5

I
|-

P
MKV84-1709

Figure 3-3

Large-Scale Ethernet Configuration

The following constraints must be observed when planning the Ethernet Local Area Network.
®

Each coaxial cable segment can have a maximum length of 500 m (1640.5 ft).

A maximum of 100 transceivers can be attached to each coaxial cable segment.

The transceiver drop cable, connecting the transceiver to a station, can be a2 maximum of 40
m (131.2 ft).

3-4

Steps followed for configuring a single segment are repeated for each segment in a multiple
segment mstallatmn

Cable segments separated by up to 100 m (328.1 ft) are genemlly interconnected using local
repeaters. Remote repeaters may be used if special environmental problems exist.
Multiple remote and local repeaters may be used.

For cable segments separated by greater than 100 m (328.1 ft) to 1000 m (3281.0 ft), use
remote repeaters.

If more than one remote repeater is used, the longest total fiber-optic path must not exceed
1000 m (3281.0 ft).

3.2.1

Planning Guidelines

The following general planning guidelines are presentedin the preferred order of executzon
To determine the coaxial cable pathway, the system planner should:
Locate the host systems on the floor plan.

Locate the nearest riser pole or floor access hole to the system.

Draw a 3 m (9.8 ft) radius circle around the riser pole or floor access fitting (refer to
Appendix B).
s

Try and have the coaxial cable path intersect each of these circles (refer to Appendix B).

Using a central hallway, the coaxial cable will be more accessible for future expansion.
3.2.2

Recorded Information

Record the following information on the marked-up floor plans, along with any critical dimensions of

cableways developed during the site survey.

Locations of all planned (current) stations, including servers and personal computers.

Locations of all proposed (expansion) stations, including terminal servers and personal
computers.

‘

Locations of all between-floor risers.

Locations of any hidden obstructions to the coaxial cable path found during the survey.
Location of the environmental airspaces for each room or floor.
Location of the proposed system grounds.
Locations of all riser poles or floor cable service fittings.
Recording of ceiling heights and all interfloor distances.
Location of drop ceilings.
Location of raised floors.

Location of cable troughs and conduits.

3-5

Location of interbuilding cable paths, such as; conduits, cable troughs, and underground
tunnels.

Location of currently used floor-to-floor cable paths.

Recording of floor thickness and type of material if the installation of coaxial cables is to péss
through the floor.
A

3.2.3 Transceiver Drop Cable Targeting
The system planner must first determine where all the existing and planned systems’ or active
systems’

components are located, and where they could be connected to the coaxial cable.

Next, the planner must determine the length of transceiver drop cable that is requited to connect the

planned system or active system components to the H4000 transceiver at the coaxial cable. The

the proposed transceiver drop cable is calculated as follows.
®

Allow I m (3.2 ft) to reach from the system’s (host) connection panel to the floor.

Use the floor plan to measure the distance (floor distance) from the host or active system’s
components, to the nearest entry point (riser pole, floor fitting, or hollow wall).

Add to the sum of these values, the length of transceiver drop cable rise needed to reach the
plane of the coaxial cable. Remember, in an above ceiling installation, the coaxial cable is
typically 0.5 m (1.6 ft) above the suspended ceiling.

length of

Allow an additional 3 m (9.8 ft) to permit the attachment of the transceivers at the appropriate
mounting locations. This is done because the H4000 transceivers are attached to the coaxial

cable only at the installation bands on the coaxial cable.

Choose a standard transceiver drop cable length that is greater than the above sum. Do not
exceed 40 m (131.2 ft) in length overall when connecting to a host or server.

Multiple cables may be joined to obtain the desired length, but single cables are easier to pull
and are more rugged.

An equation to determine the radius of the target circle can now be used.
2 =

Floor Distance + Riser Length + [1 m (3.2 ft)] + [3 m (9.8 ft)]

Target Radius = Cable Length — =

Once the radius has been determined, use the floor plan drawing scale to draw a target circle around the
selected entry point with a radius equal to the radius just calculated. This indicates graphically,
the area
where a connection to the coaxial cable can be made.
The coaxial cable pathway is then drawn on the floor plans connecting each of the target areas. The
proposed Ethernet coaxial cable pathway is then measured. If the coaxial cable path is over 500 m (1640
ft), the planner can readjust the path, or multiple segments can be specified and are connected through the
use of an Ethernet repeater.
The system planner should be aware that if a maximum length of transceiver drop cable is selected, the
radius is maximized. This results in a shorter coaxial cable. If on the other hand a minimum length of
transceiver drop cable is used, the target circles are smaller and this requires that a longer coaxial cable be
specified. Generally, it is more cost effective to minimize transceiver drop cables. When systems are
clustered, consider the use of a DELNI interconnect to reduce transceiver count and cost of drop cables.

3-6

Add an arrow to the circle pointing to the system to be served from that particular riser pole or floor
fitting.

An example of transceiver cable targeting is shown in Appendix B.
3.2.4

Coaxial Cable Path Layout

Three different procedures are discussed: single-floor, multifloor, and multibuilding installations.
SINGLE-FLOOR INSTALLATIONS

For single-floor installations, the following procedure should be used for laying out the coaxial cable path

on the floor plans.

Start near a proposed station location and draw a line on the plan representing the proposed
coaxial cable path.

This path should follow main hallways, where possible, and pass through all target circles. If
possible, the coaxial cable path should cover the building, including floor areas to be served in
any expansion plans.

Extend the coaxial cable so that the ends can be located at or near floor level for access of test
equipment. These cable ends should be concealed to prevent tampering. The cable ends may be
coiled up and placed in the ceiling.

MULTIFLOOR INSTALLATIONS

The same procedures for laying out the cable path for a single-floor installation apply for multifloor
installations as well. In addition, the following steps must also be followed.

Locate a common riser (such as an elevator shaft) that goes between all the floors that are to be
served.

Start the coaxial cable pathway, on each floor, at the common interfloor riser.

Attempt to encircle each floor with the coaxial cable if the building is a high-rise office tower or
other structure that contains a doughnut-shaped floor with a utility core in the center of the site
‘

floor.

MULTIBUILDING INSTALLATIONS

Buildings that are physically connected to each other may use local repeaters to join the individual
Ethernet coaxial cable segments in each building. For short runs, a single coaxial cable segment may
service two buildings.

In cases where buildings are not physically connected, Digital Equipment Corporation recommends that
the system planner specify the use of remote repeaters and fiber-optic cables to connect the individual
networks in each building. Use of remote repeaters and fiber-optic cables:
Eliminates any potential interbuilding grounding problems, and
®

Isolates the between-building links from the individual building coaxial cable. Individual operation of one of the networks is possible should problems arise with one network or with the

between-building link.

3-7

3.2.5 Plan Iteration
If the total path length of any coaxial cable is over 500 m (1640.5 ft), divide the cable into two segments
joined together by repeaters or reduce the cable length. The use of repeaters 1s recommended. There
are
several ways that the cable length can be reduced. Each method involves trading off the length
of the
transceiver drop cable for coaxial cable length. In general, it is more efficient and cost effective
to use
longer coaxial cable and shorter transceiver drop cables. This also has the advantage of providing
greater
coverage for future expansion. Various methods of reducing the length of the coaxial cable are:

Eliminating lengths of coaxial cable path that reach proposed (future) stations. Additional
repeaters and coaxial cable segments can be added later, if required.

Replotting the coaxial cable pathway using target-to-target runs between stations and running
the cable along diagonals instead of following the building hallways.

Using longer transceiver drop cables.

Multiple passes may be needed to achieve a workable coaxial cable pathway layout.
3.3 PHYSICAL CHANNEL COMPONENT CONSIDERATIONS
Various Ethernet physical channel component considerations must be taken into account when planning
the Ethernet Local Area Network. These considerations are discussed in the following sections.

oI,

3.3.1
Coaxial Cables
|
The Ethernet coaxial cable is the main transmission medium of an Ethernet network through which all
Ethernet data traffic flows. The following sections should help the system planner to plan a trouble-free
installation of the coaxial cable.
COAXIAL CABLE RULES
The following rules should be observed.
®

Do not subject the coaxial cable to bends of less than 20 ¢cm (7.9 in) radius. This bend limit
ensures the concentricity of the center conductor and cable shield.

Connect each coaxial cable segment to a network earth reference ground.

Where transceivers are used, install the coaxial cable in an area that remains between 5°C to

50°C (41°F to 122°F) and 10% to 90% humidity (noncondensing).

Ethernet coaxial cables without connectors or H4000 transceivers may be exposed to a temperature range of —18°C to 150°C (0°F to 302°F), and a condensing atmosphere.
FEP COAXIAL CABLE MATERIAL
Digital Equipment Corporation’s BNE2A Ethernet coaxial cable has been manufactured to meet current

electrical code requirements governing the installation of nonconduit cables in environmental airspaces.

The model BNE2A coaxial cable contains a Teflon® FEP (fluoridated ethylene propylene copolymer)

fluorocarbon insulation and jacket covering. This material is ‘“classified as fire and smoke only” in
accordance with the National Electrical Code (NEC) Article 725-2(b) entitled *“Remote-Control, Signaling and Power-Limited Circuits”. This cable is approved as a “low-smoke” cable, and where local
building codes approve, it may be installed in environmental airspaces without a conduit.

S———

—

NOTE

Using FEP insulated coaxial cables does not preclude the need to investigate building code require-

ments for cable installation in environmental airspaces. Although the FEP cable has been approved
by a national authority (Underwriters’ Laboratories), this does not constitute approval by the local
authorities. Always check the local codes before
purchasing cables.

PVC COAXIAL CABLE MATERIAL

The model BNE2B coaxial cable is made with polyvinyl chloride (PVC) insulation and jacket covering.
PVC cables are not approved for installation in environmental airspaces per the requirements of NEC
Article 725-2(b). PVC cables may be used in:
e

e
e

(able troughs in open areas,

Open spaces, such as factory ceilings, or
Beneath raised floors, if not an environmental airspace.

Additional information on the coaxial cables may be found in Appendix A.
COAXIAL CABLE, STANDARD LENGTHS
Digital Equipment Corporation can supply, off-the-shelf, four standard lengths of coaxial cables. These
standard lengths of cable come prefitted with male type N connectors at each end, and require no special

tools when they are joined together with barrel connectors to make one contiguous coaxial cable segment.
- Standard coaxial cable lengths may be joined together in any combination as long as the 500 m (1640.5 ft)
length is not exceeded. Standard lengths of coaxial cable are listed in Table 1-1.
When the total length of the coaxial cable has been calculated, refer to Table 3-1 to select the necessary
cable sections to make up the required coaxial cable segment. Select the cable lengths (sections) necessary
that equal or exceed the total length required.

COAXIAL CABLE TOOLS
If the coaxial cable is to be repaired, the following tools are required for the proper installation of coaxial
connectors.

(Coaxial cable cutter

DIGITAL P/N 29-24667, or

—

Benner-Nawman P/N UP-B76, or equivalent
(Benner-Nawman, Inc., Pleasant Hill, California)

(Coaxial cable stripper

—

DIGITAL P/N 29-24668, or

—

Ideal P/N 445-164, or equivalent
(Ideal Industries, Sycamore, Illinois)

AN,

Table 3-1

Cable Lengths vs Building Application

Length of Installation*

Meters

—

Number of Cable Sections Required
23.4 mi
117.0 mi

Feet

[ - 23

3 - 75

23 - 46+
46 - 70

75
— 151+
151 — 230

70 - 93+
93 - 117

230 - 305+

117- 140

384 — 459

140 - 163+

459 — 535+

163 — 187
187 - 210t

535 - 614

614 — 689+

I
1

210 - 234
234 - 257

689 — 768
768 — 843

257 — 280t

843 — 919+

2
2

280 - 304
304 - 327+
327
- 351 .

351 - 374
374 - 397+

305 — 384

919 — 997
997 — 1073+
1073
= 1152

397 — 421

1152 - 1227
1227 - 1302+
1302 - 1381

421 - 444+
444 — 468
468 — 491

1381 — 1457+
1457 — 1535
1535 — 1611

400 - 500

1311 - 1640

(BNE2A /B-ME)

1
2

3
3
3

3
4

*Lengths are approximates.
fThese lengths are composed of multiple short sections. To minimize the number of connectors
in a
segment, it may be preferable to select the next longer cable (the next line entry in the table)
instead of
using multiple short sections that have many connectors.

SRR,

These specific lengths are selected to minimize the successive in-step buildup (in-phase addition)
of
reflections from connectors.
123.4 m (76.8 ft) DIGITAL P/N BNE2A/B-MA

70.2 m (230.3 ft) DIGITAL P/N BNE2A/B-MB
117.0 m (383.9 ft) DIGITAL P/N BNE2A/B-MC

3-10

Connector crimp tool and die set

—~

DIGITAL tool P/N 29-24662
DIGITAL die set P/N 29-24663

Military P/N MIL-T-22520

—~

Amphenol tool P/N 227-944, or equivalent
Amphenol die set P/N 227-1221-25, or equivalent

(Amphenol North America Division, Bunker Ramo Corporation, Oak Brook, Illinois)

Male N connectors

—

DIGITAL P/N H4056-00 (package of two)

—

Military P/N M39012/01-0502

Amphenol P/N 82-4426, or equivalent

The procedures for installing coaxial cable connectors on coaxial cable are provided in Volume II of this
manual.

Transceivers

3.3.2
the Ethernet
The H4000 transceiver is the interface that connects stations physically and electricallyeetoinstallatio
n of
trouble-fr
a
plan
to
planner
system
the
help
should
coaxial cable. The following sections
drop
r
transceive
the
of
n
connectio
for
connector
D
type
male
a
has
r
the H4000 transceiver. The transceive
cable.

TRANSCEIVER PLACEMENT

n bands
The H4000 transceivers are attached to the coaxial cable at the installation bands. These installatio
These
long.
in)
(0.2
cm
0.5
about
are
bands
The
cable.
coaxial
the
on
rings
appear as dark colored annular
from
reflection
signal
of
effects
the
minimize
to
3-4)
Figure
to
(refer
ft)
bands are spaced every 2.5 m (8.2
transcelivers.

The maximum number of transceivers allowed on a Ethernet coaxial cable segment is 100. This ensures
that all installed transceivers can receive signals broadcast from any other transceivers on the coaxial
cable. At 2.5 m (8.2 ft) spacing, 100 transceivers require about 250 m (820.2 ft) of coaxial cable.
The nominal number of transceiver installation bands per cable section are as follows.
23.4 m (76.8 ft) — 9 transceiver installation bands
70.2 m (230.3 ft) — 27 transceiver installation bands
117.0 m (383.9 ft) — 45 transceiver installation bands
500.0 m (1640.5 ft) — 199 transceiver installation bands
NOTE

Although a 500 m (1640.5 ft) segment has more
than 100 installation bands, the 100 transceiver limit
still applies.

These figures are based on the minimum number of transceiver installation bands that appear along an
length of coaxial cable. On the two longer sections of cable, there may be one or two additional installatio
bands due to manufacturing tolerances.

3-11

Normally, any transceiver installation band on a coaxial cable may be used. Position
the transceivers so
that no interference occurs near the cable end or at the barrel COoNnectors.

Where the placement of H4000 transceivers is especially dense, the system planner should
consider the use
~of a DELNI interconnect that can serve up to eight stations from one H4000
transceiver.
TRANSCEIVER

INSTALLATION

BANDS

SR,

ARy

DIGITAL BNE2A-Mx COAXIAL CABLE
———————

2.5 METERS (8 FEET, 2 INCHES)

J
MKV84-1710

Figure 3-4

Coaxial Cable Installation Bands

3.3.3 Transceiver Drop Cables
To assist the planner, Digital Equipment Corporation can supply three types of
cables; PVC type drop
cables, FEP type drop cables, and office PVC drop cables.
TRANSCEIVER DROP CABLE MATERIALS
|
The model BNE3A (straight connector) and BNE3B (right-angle connector) transceiver
drop cables are
made with polyvinyl chloride (PVC) insulation and jacket covering. PVC cables
are not approved for
installation in environmental airspaces (refer to Figure 2-5) per the requirements
of NEC Article 725-2(b).

NOTE

The BNE3A (straight connector) and BNE3B
(right-angle connector) transceiver drop cables have

a recommended minimum bend radius of 5 cm (2 in).

ey,

The model BNE3C (straight connector) and BNE3D (right-angle connector)
transceiver drop cables

contain a Teflon® FEP (fluoridated ethylene propylene copolymer) fluorocarb
on insulation and jacket
covering. This material is “classified as fire and smoke only” in accordance
with the National Electrical

Code (NEC) Article 725-2(b) entitled “Remote-Control, Signaling and Power-Lim
ited Circuits”. This
cable is approved as a “low-smoke’’ cable, and where local building codes approve, it
may be installed in
environmental airspaces (refer to Figure 2-5) without a conduit.

3-12

NOTE

The BNE3C (straight connector) and BNE3D
(right-angle connector) transceiver drop cables have
a recommended minimum bend radius of 10 cm (4
in).

The model BNE4A (straight connector) and BNE4B (right-angle connector) transceiver drop cables are
made with polyvinyl chloride (PVC) insulation and jacket covering. These cables come in only two short
lengths and are intended for office installations only. These cables would generally be routed from a wallmounted Etherjack connection box to the nearby host system. Their gray color generally blends into the
office decor. These cables are considerably more flexible than the other types of transceiver drop cables.
The maximum cable length rules shown in Table 3-2 must be observed.
TRANSCEIVER DROP CABLE RULES

DIGITAL transceiver drop cables, models BNE3A, BNE3B, BNE4A, and BNE4B PVC insulated
cables, may not be used in environmental airspaces. These cables may be used in applications where
the transceiver drop cable would not be exposed to environmental or building ventilation airflow.

DIGITAL transceiver drop cables, models BNE3C and BNE3D FEP insulated cables, may be used
in any environment where nonconduit cables are permitted.

Both FEP and PVC type cables may be combined in a single run. If this is done, the FEP-insulated
cable would be used within the environmental airspace, and the PVC-insulated cable would be used
outside the environmental airspace. In this configuration, the FEP cable must be joined to the PVC
cable outside the airspace [an Etherjack connection box (DEXJK) may be used for this connection].
s

The transceiver drop cables, all types, should be installed only in environments that range from 5°C to
50°C (41°F to 122°F, noncondensing atmosphere).

TRANSCEIVER DROP CABLES, STANDARD LENGTH

Any combination of drop cable lengths may be connected together to achieve the necessary total length. It
is recommended that no more than two cables be used.

The procedure for installing cable connectors on the transceiver drop cable is provided in Volume II of this
manual.

Digital Equipment Corporation supplies transceiver drop cables as listed in Table 3-2. The table provides a

“cross-reference of application length and recommended cable type.

Transceiver drop cables can be supplied with two different types of connector heads.

Straight Head - Installed on the BNE3A, BNE3C, and BNE4A cables to allow the transceiver

drop cable to be strain-relieved to the coaxial cable at the H4000 transceiver connection.
|

Replacement kit number, H4054.

Right-Angle - Installed on the BNE3B, BNE3D, and BNE4B cables for bulkhead applications

Replacement kit number, H4055.

3-13

Table 3-2

Transceiver Drop Cable Applications

Condition

Cable Types

Maximum Lengths

H4000 transceiver to host or

BNE3 (only)
BNE3 + BNE4-02
BNE3 + BNE4-05
BNE4 (only)

40 m (131.2 ft)

32 m (105.0 ft)
25 m (82.0 ft)
10 m (32.8 ft)

DELNI interconnect to host or

BNE3 (only)

server

BNE3 + BNE4-02
BNE3 + BNE4-05
BNE4 (only)

40 m (131.2 ft)

32 m (105.0 ft)
25 m (82.0 ft)

BNE3 (only)
BNE3 + BNE4-02

40 m (131.2 ft)

BNE3 + BNE4-05
BNE4 (only)

25 m (82.0 ft)

BNE3 (only)
BNE3 + BNE4-02
BNE3 + BNE4-05
BNE4 (only)

50 m (164.1 ft)
42 m (137.8
ft)

BNE3 (only)
BNE3 + BNE4-02
BNE3 + BNE4-05

50 m (164.1 ft)
42 m (137.8 ft)

server

H4000 transceiver to DELNI
interconnect to host or server
(total of both cables)

H4000 transceiver to repeater

DELNI interconnect to DELNI
interconnect (cascaded)

BNE4 (only)

10 m (32.8 ft)

ARG

32 m (105.0 ft)
P

10 m (32.8 ft)

30 m (98.4 ft)
12 m (39.4 ft)

ADJUSTING TRANSCEIVER DROP CABLE LENGTHS
In estimating the transceiver drop cable length, a standard slack length of 3 m (9.8 ft) is used. This length
provides sufficient slack to serve two transceivers from the same entry point. When three transceivers are
served by a single entry point, one of the drop cables must be lengthened to accommodate the spacing of
installation bands on the coaxial cable (refer to Figure 3-5). If more than three transceivers are to be
served by a single entry point, the planner should consider the use of a DELNI interconnect that can serve
up to eight host systems.
|

—

)

Any adjustments made to the transceiver drop cable lengths should be noted on the Station Transceiver
Drop Cable Worksheet (Appendix D) along with the: riser length, floor run, entry point distance, and the

actual total drop cable length for each station.

LOCATING TRANSCEIVER DROP CABLES ON THE FLOOR PLANS
After determining the lengths of the drop cables needed to serve each station, the planner should draw the
cables on the second sheet of the floor plan (refer to Figure 3-2). This floor plan is given to the installer and
shows where each cable goes for each specific system. The planner should also indicate on the floor plan if
there is more than one drop cable being used to serve a station, and also what type material is being
specified.

SO,

3-14

—
|
—

3 M| (9.8 FT) .

Zi';&s%%:ESSDROP
|

POINT

STATION A

STATION C WILL REQUIRE

AT LEAST 2.5 M (8.2 FT)

MORE TRANSCEIVER DROP
CABLE THAN STATIONS

AORB

ENTRY

TRANSCEIVER FOR

A TRANSCEIVER FOR

‘

2.5 M (8.2 FT

TRANSCEIVER FOR

STATION B

TRANSCEIVER

ATTACHMENT
MARK FOR

STATION C

(PROPOSED)
MKV85-2721

Figure 3-5

Multiple Station Transceiver Drop Cable Adjustment

DELNI Configuration

3.3.4

The DELNI Local Network Interconnect is a clustering device that can interconnect up to eight devices
that have an Ethernet communications controller (DEUNA, DEQNA, DECNA). The DELNI interconnect can be used in either the local or global modes of operation (refer to Appendix E).
If a DELNI interconnect is to be used, the planner should consider the following.

The DELNI interconnect requires ac power and comes with a 190.5 cm (75 in) power cord.

For global mode operation, the DELNI interconnect is connected to an H4000 transceiver on a

coaxial cable segment.

When configured for global mode operation, the DELNI interconnect has a maximum total
transceiver drop cable length of 40 m (131.2 ft).

Calculate the total drop cable length by adding together the length of the cable going from the transceiver
to the DELNI interconnect, plus the length of the cable coming from the communications controller to the
DELNI interconnect.

3.3.5

Repeater Configuration

The Ethernet repeater is used to expand a network beyond the 500 m (1640.4 ft) segment limitation. Two
types of repeaters may be specified; a local repeater (DEREP-AA/AB) for connecting two coaxial cable
segments together that are no more than 100 m (328.1 ft) apart, or remote repeaters (DEREP-RA/RB)
which consist of two local repeaters that are a maximum of 1000 m (3281.0 ft) apart and are connected by
fiber-optic cable.

3-15

LOCAL REPEATER DEREP-AA/AB
The local repeater connects to each coaxial cable segment via a transceiver drop cable and an H4000
transceiver.

If a local repeater is to be used, the planner should consider the following.
®
®
®

The local repeater has a transceiver drop cable length limitation of 50 m (164.1 ft).
The local repeater requires ac power and comes with a 190.5 cm (75 in) power cord.
The rear panel contains status LED:s.

REMOTE REPEATERS DEREP-RA/RB
A remote repeater consists of two repeater halves. Each half is similar to the local repeater but includes
additional electronics for the fiber optics.

If a remote repeater is to be used, the planner should consider the following.

Each remote repeater half requires ac power and comes with a 190.5 cm (75 in) power cord.
A

Each remote repeater half connects to a coaxial cable segment through a transceiver drop cable

and an H4000 transceiver.
®

Each transceiver drop cable can be up to a maximum of 50 m (164.1 ft) in length.

Each remote repeater half connects to a duplex fiber-optic cable.

3.3.6 Fiber-Optic Cable
A fiber-optic cable is an optical transmission medium and is required whenever remote repeaters are used
to connect separate segments. The following summarizes the fiber-optic cable specifications.

The remote repeater DEREP-RA/RB is designed to accept 100 micron Corning type 1508TM, graded
index, glass-on-glass fiber.

OPTICAL REQUIREMENTS
e

Bandwidth greater than, or equal to, 300 MHz per kilometer at 850 nm.
S

(Cable attenuation less than, or equal to, 6 dB per kilometer at 850 nm over the operating temperature
range.

CONNECTOR TYPE
Amphenol type 906TM SMA style connector.
TOTAL SYSTEM LOSS
Less than 10 dB to be verified after the installation.
ENVIRONMENTAL
General purpose 0°C to 70°C (32°F to 158°F)

95%, noncondensing

Some cable vendors provide aerial afid plenum cable. Aerial cable may be used to connect two buildings
through the air or in conduit underground. Plenum cable should be selected where the cable path is
through return air plenums.

Corning 1508 is a trademark of Corning Glass Works.

Amphenol 906 is a trademark of Amphenol North America, Division of Bunker Ramo Corp.

3-16

If a fiber-optic cable is to be used, the planner should consider the following.

3.4

A fiber-optic cable connects each of the two remote repeater halves.

The fiber-optic cable has two separate glass elements (Corning 1508TM type fiber).

The maximum fiber-optic cable length is 1000 m (3281.0 ft).

PLANNING A SYSTEM GROUND

Installation of the Ethernet coaxial cable requires that the shield of each coaxial cable segment be
grounded to comply with electrical code requirements (refer to Figure 2-8). The system planner must
select three components when planning the system’s ground.
e
e
e

(Coaxial segment shield connection point.
Network earth reference point.
Earthing conductor (ground wire) length.

The actual location of the network earth reference point is selected by the planner from a list of pretested
alternatives.

The planner specifies a coaxial cable connector near the earth reference point, determines the necessary
hardware (ground clamp, earthing conductor, and mounting hardware) to connect the shield to the ground,
and determines the length of the earthing conductor.

The planner should remember the following points.
e

The shield of each coaxial cable segment should connect to the ground at a coaxial cable
connector.

The length of the earthing conductor should be kept to a maximum 15 m (49.2 ft).

The network earth reference point should be physically wired to a grounding electrode by:
—

A direct separate conductor.

—

A metallic conduit that is connected to the grounding electrode.
NOTE

This is to comply with the ground bonding practices
outlined in Article 250 of the National Electrical
Code.

If the nearest coaxial cable connector is more than 15 m (49.2 ft) from the network earth reference point,
the coaxial cable sections must be repositioned to move one of the connectors nearer to the reference point.
The earthing conductor should be:
e
®

Solid AWG 8 wire
Black insulation
WARNING

DO NOT use a green insulated earthing conductor,
as electrical workers may later confuse this green
wire for a safety ground.

If the network earth reference point is the threaded end of the metallic conduit, use bonding wedges or
other hardware available from an electrical supply house to connect the conductor.
3-17

po——

3.4.1
Single-Point Grounding
Single-point grounding should be used on all Ethernet coaxial cable segments that remain inside the
building. The installer should be supplied with either electrical tape or insulation boots for insulating all

other exposed connectors on the coaxial cable (except the network earth reference connection).

3.4.2 Multipoint Grounding
A coaxial cable that spans the distance between two buildings must be enclosed in a conduit so that the

cable is not exposed to the outside environment (the coaxial cable is not suitable for direct burial
applications).

When multipoint grounding is appropriate, a barrel connector must be located as close as possible to the
coaxial cable entry point in each building to provide a connection for the earthing reference conductor.
Use the shortest length of coaxial cable that spans the distance between the two buildings. A connector

must not be located within the conduit.

NOTE
If the interbuilding conduit is greater than 117 m
(383.9 ft), then a custom length cable has to be used.
Do not pull sections of coaxial cables that are joined
by barrel connectors.
AN

Should the coaxial cable be longer than necessary to reach between buildings, excess cable should be coiled
up close to the building entrance point. This enables the use of a short earthing conductor to reach from
the connector to the ground point (refer to Figure 3-6).
3.5 ETHERNET NETWORK SCHEMATICS
|
A schematic is a simplified diagram of the Ethernet Local Area Network. A schematic cannot show the
detailed placement of the network equipment, but it can provide a functional overview of the system’s
design. A schematic can show the number of coaxial cable sections that make up a segment and their

lengths, barrel connectors, transceivers, transceiver drop cables and their lengths, repeaters, and DELNI
interconnects.

The schematic is created from information on the floor plan and is used to summarize and cross check the
physical channel component Bill of Material. Figure 3-7 shows the Ethernet floor plan symbols and Figure
3-8 shows a sample Ethernet schematic.

3-18

GROUND

‘

CLAMP

?r|

| +— J-HOOK
100

“

INTERBUILDING

4~ CONDUIT

LOOPS OF

FAPT AT

it1] / COAXIAL CABLE

EARTHING
CONDUCTOR

NETWORK EARTH
REFERENCE

METALLIC

CONDUIT \

”..........

- .

MKV84-1711

Figure 3-6

Excess Coaxial Cable Coiled to Minimize the Length of the Earthing Conductor

3-19

COAXIAL CABLE

TERMINATOR

ETHERNET TRANSCEIVER

H4000

STATION/FUTURE STATION

P
‘

LJd

RISER

BARREL CONNECTION

N
N\

ENTRY POINT

DROP POLE OR FLOOR SERVICE
FITTING FOR TRANSCEIVER

CABLE

TRANSCEIVER CABLE
3 SLASHES THROUGH CABLE
AT EACH CONNECTION

15 M (48.2 FT) TRANSCEIVER CABLE

ONE 10 M (32.8 FT) CABLE AND

ONE 5 M (16.4 FT) CABLE

NETWORK SYSTEM GROUNDS

AT BARREL CONNECTOR

hv4
<— GROUND CLAMP
<«——

EARTHING CONDUCTOR

— «— NETWORK EARTH

REFERENCE

® AT TERMINATOR

<+— GROUND CLAMP
4—FEARTHING CONDUCTOR

— «@— NETWORK EARTH
REFERENCE

ENVIRONMENTAL AIRSPACE

RED LINE

OUTLINING AREA
EXTREME TEMPERATURE/HUMIDITY

Z/ZZ"//

MKVB84-1712

Figure 3-7

Ethernet Floor Plan Symbols

3-20

23.4 M (76.8 FT)

p, &

70.2 M (230.3 FT)

117.0 M (383.9 FT)

COAXIAL CABLE COMES IN SECTIONS WITH CONNECTORS AT EACH END.

117.0 M (383.9 FT)

70.2 M (230.3 FT)

MULTIPLE SECTIONS CAN BE CONNECTED USING BARREL CONNECTORS TO MAKE A LENGTH OF CABLE UP TO 500 M (1640.4 FT) LONG.

H4000

p 4

TERMINATORS PLACED AT BOTH ENDS OF EVERY COAXIAL CABLE LENGTH [(500 M (1640.4 FT)] MAKE A COAXIAL CABLE SEGMENT.

H4000

( T )

TRANSCEIVERS ARE ATTACHED TO THE CABLE NEAR STATION LOCATIONS. TRANSCEIVERS CAN BE NO CLOSER

H4000

H4a000

H4000

( v >

TOGETHER THAN 2.5 M (8.2 FT). THE MAXIMUM IS 100 TRANSCEIVERS PER COAXIAL CABLE SEGMENT.

TRANSCEIVER DROP CABLES CONNECTING TRANSCEIVERS TO STATIONS.
MKVB4-1713

Figure 3-8

Sample Ethernet Schematic

3-21

SO,

ORISR

‘s

APPENDIX A

ETHERNET PHYSICAL

CHANNEL COMPONENTS

A.1 ETHERNET PHYSICAL CHANNEL COMPONENTS
DIGITAL Ethernet physical channel components consist of:
Ethernet coaxial cables, barrel connectors, and terminators
H4000 transceivers
Transceiver drop cables
Repeaters (DEREP)
Fiber-optic cables

”

Local area interconnects (DELNI)
A.2 COAXIAL CABLE COMPONENTS
The following sections describe the components that make up the coaxial cable.
A.2.1

Ethernet Coaxial Cables

The Ethernet coaxial cable is the transmission medium for the Ethernet Local Area Network. This coaxial
cable is a round, 1.0 cm (0.4 in) diameter, insulated, shielded coaxial cable. This cable is supplied in four
different lengths shown in Table A-1.

Table A-1

A.2.2

Ethernet Coaxial Cable Lengths

Lengths
Meters/Feet

DIGITAL Part Number
FEP
PVC

23.4 m (76.8 ft)

BNE2A-MA

BNE2B-MA

70.2 m (230.3 ft)
117.0 m (383.9 ft)
500.0 m (1640.5 ft)

BNE2A-MB
BNE2A-MC
BNE2A-ME

BNE2B-MB
BNE2B-MC
BNE2B-ME

Connectors

The Ethernet backbone coaxial cable incorporates three types of connectors.
e
@

(Coaxial cable end connectors
Barrel connectors

Terminators

Table A-2 lists the physical dimensions of these connectors.

Table A-2

Coaxial Cable Connector Sizes

Type

Outside

Connector

End Connector
Barrel Connector
Terminator

Diameter

Maximum
Length

2.1 cm (0.83 in)
1.9 cm (0.75 in)
1.9 cm (0.75 in)

4.1 cm (1.61 in)
4.6 cm (1.81 in)
3.6 cm (1.41 in)

COAXIAL CABLE CONNECTORS
Each Ethernet coaxial cable section has a male type N connector installed at each end that can be ordered
separately (2 per package).
e

(Connector: Male type N, crimp-on connector

DIGITAL P/N: H4056
BARREL CONNECTORS
Barrel connectors are used to join Ethernet coaxial cable sections together to form a coaxial cable segment.
®

Barrel connector: Type N, female-to-female

DIGITAL P/N: 12-19817-01
Assembled connection: 10.5 cm (4.13 in)

—

TERMINATORS
Terminators must be installed at each end of the Ethernet coaxial cable segment to provide a resistive
match to the characteristic impedance of the coaxial cable.

Characteristics: 49.9 Q + 1 percent

DIGITAL P/N: 12-19816-01
GROUND CLAMP
Ground clamps are used for attaching the ground wire to the coaxial cable.

e
A.2.3

DIGITAL P/N: 12-21766-01.

Ethernet H4000 Transceiver

The DIGITAL H4000 transceiver is the interface that connects computer stations physically and electrically to the Ethernet coaxial cable. The transceiver transmits and receives signals to and from connected
stations, while at the same time, it is capable of detecting Ethernet message collisions. The transceiver
provides electrical isolation and high impedance to the coaxial cable.

The H4000 transceiver consists of a small printed circuit board contained in a rugged, compact, plastic
housing. The housing also contains a nonintrusive cable tapping assembly that is used to make physical
contact with the Ethernet coaxial cable.

DIGITAL P/N: H4000
Length
Width

Height

27.7 cm (10.9 in)
9.5 cm (3.7 in)
9.0 cm (3.5 in)

Weight

1.4 kg (3.0 1lbs)

A.2.4

Transceiver Drop Cable

Transceiver drop cable components include the transceiver drop cable and the drop cable connectors.

The transceiver drop cable provides the connection between the H4000 transceiver and the Ethernet
controller mounted in the host system or the DELNI interconnect. Drop cables may be joined together to
meet the required length. However, transceiver drop cable lengths must not exceed the values listed in

—

Table 3-2.

There are three styles of drop cables available.

BNE3A (straight connector) or BNE3B (right-angle connector) - polyvinyl chloride (PVC)
insulation. These cables are not approved for installation in environmental airspaces as defined
by NEC Article 300-22(c).

BNE3C (straight connector) or BNE3D (right-angle connector) - flouridated ethylene propylene copolymer (FEP) insulation. These ‘cables are approved by UL for installation in environmental airspaces and meet the requirements of NEC Article 725-2(b).

BNE4A or BNE4B - a special, short length office cable made with polyvinyl chloride (PVC)
insulation. These cables are not approved for installation in environmental airspaces as defined
by NEC Article 300-22(c).

This 0.6 cm (.24 in) diameter cable is flexible and has molded end connectors. The attenuation

is four times that of the BNE3 cables. When using the BNE4 cables, be sure to refer to Table 32 for maximum transceiver drop cable lengths.

Transceiver drop cables come in various lengths as shown in Table A-3.
Table A-3

|
-

M
m

—

Transceiver Drop Cable Lengths

Lengths

BNE3

BNE4

2 m (6.6 ft)
5 m (16.4 ft)

X
X

40 m (131.2 ft)

10 m (32.8 ft)

~ Transceiver drop cables have a diameter of 1.3 cm (0.5 in) except for the BNE4 cable which is 0.6 cm (0.2
in).

Transceiver drop cable connectors consist of a:
®

]15-pin “D” subminiature type connector.

Female connector with a slide-latch locking assembly (for mounting to the H4000 transceiver).

Male connector with locking posts (for mounting to the station controller).

Straight-head backshell (A or C versions).

Right-angle backshell (B or D versions).

Table A-4 lists the dimensions of the drop cable connector heads.
Table A-4

Dimensions of Drop Cable Connector Heads
e

Length*
Width
Height

Straight Entry
P/N H4054

Right-Angle Entry
P/N H4055

5.4 cm (2.1 in)
4.4 cm (1.7 in)
1.8 cm (0.7 in)

6.0 cm (2.4 in)
3.9 cm (1.5 in)
1.8 cm (0.7 in)

*Length measures the connector body only. Allow 1.9 c¢m (0.7 in) additional length for cable ferrule.
A.3 FIBER-OPTIC CABLES
Digital Equipment Corporation offers a general purpose fiber-optic cable. This cable is suited for use inside
a building where the cable will not be routed through air plenums. It may also be used in conduit, between
buildings where the environmental conditions of temperature and humidity do not exceed the cable
specifications.

Option
Designation
BN25B-60
BN25B-90
BN25B-A5
BN25B-C0
BN25B-E0

BN25B-H5
BN25B-L0

Description

60 m (196.9 ft)
90 m (295.3 ft)
150 m (492.1 ft)
300 m (984.3 ft)
500 m (1640.5 ft)
750 m (2460.8 ft)
1000 m (3281.0 ft)

[

APPENDIX B

SAMPLE FLOOR PLANS
B.1

INTRODUCTION

This appendix shows the sample layout process for a small Ethernet Local Area Network. This appendix is
divided into two distinct areas; Site Survey, and Configuration Planning. In preparing this sample layout
process, the following conditions have been defined.

The installation is a suspended ceiling installation.
The suspended ceiling is 3 m (9.8 ft) high.

The suspended ceiling is an environmental airspace acting as the return air plenum for the airconditioning system.

Local building codes allow the use of authority-approved (UL listed) nonconduit cables in the
environmental airspaces.

Riser poles can accommodate multiple transceiver drop cables.

The Ethernet coaxial cable is being routed to accommodate as many stations as possible.
B.2

SITE SURVEY PROCEDURES

Using a copy of the floor plan (refer to Figure B-1), it is the responsibility of the surveyor to:
Locate all stations and proposed stations on the floor plan and assign a number to each station.
Locate all riser poles, or floor fittings, that can be used to route the transceiver drop cable to
serve each station.

Locate the network earth reference ground. This point is usually near the electrical power
service entrance.

Locate any DELNI interconnects or DEREP repeaters on the floor plans, as required, and
assign a number to each.

Record any pertinent construction details and measurements. In this example, Station 5 is
located in a computer room having a raised floor. Because of this, two riser poles have been
noted; one to serve the station through the raised floor, the other to route the drop cable from
the raised floor to the suspended ceiling.
Mark the floor plan to show construction details, such as, the rear wall being a double-plastered
wall, and that drilling is required to enable the cable to penetrate the wall.
Record the riser length and measure the riser floor run for each station, on the Station
Transceiver Drop Cable Worksheet.
|
Submit the marked-up floor plan along with the Station Transceiver Drop Cable Worksheet to
the system planner.

B-1

B.3 CONFIGURATION PLANNING PROCEDURES
Using the floor plan that the surveyor marked-up, the system planner generates two additional floor plans.

One plan shows the actual routing of the Ethernet coaxial cable, as well as the placement of the
terminators and barrel connectors. The other plan shows the locations of the H4000 transceivers, DELNI

interconnects, repeaters, and stations.

The system planner must perform several different steps to configure the sample Ethernet Local Area
Network.
STATION TARGETING AND COAXIAL CABLE PATH PLANNING
To target the stations, the system planner must:
O

Choose a 20 m (65.6 ft) transceiver drop cable as a first estimate, where 1 m (3.3 ft) is allocated
for the floor-to-host panel rise, and 3 m (9.8 ft) is allocated for the floor-to-ceiling rise. The
remaining 16 m (52.5 ft) is divided between the floor run and the above ceiling run, [8 m (26.2
ft) each].

Draw circles having a radius of 8 m (26.2 ft) around the entry point closest to each station (as
shown in Figure B-2). Dashed lines are used since these circles are tentative. Stations 3 and 4
share a circle since they share a common riser as an entry point. Station 5 is an exception
because it is located in a raised floor laboratory and no riser is needed to reach the coaxial cable.
The station is used as the center of this circle.

NOTE
A 20 m (65.6 ft) cable is the most commonly used
length. Longer or shorter cables may be used to
optimize the design. The longest standard drop cable
available from Digital Equipment Corporation is 40
m (131.2 ft).

USRI

o R

Not all stations are within the initial circles. Stations 2 and 3 require repositioning of their drop
cables or the use of longer cables. Since both stations are quite close to their respective circles,
the planner realizes that by lengthening the floor run to reach the appropriate station, the ceiling
run is shortened by the same amount.
®

Measures (on the floor plan) the distance between the initial circle and any station outside its

circle. Any new circle is drawn for that station with a radius of 8 m (26.2 ft) minus the distance
just measured. This is the area reachable by the reduced ceiling run.
®

Redraw the circles using solid lines when the final target positions are determined (see Figure
B-3).

Draw the coaxial cable path (see Figure B-4). This path should follow hallways and aisles, and

must intersect all target circles. This path must also be located within a reasonable distance of
the network earth reference ground.

In the sample floor plan shown in Figure B-4, the coaxial cable path begins under the raised floor of the
computer room where Station 5 is located. This location allows easy access to the terminator for testing
purposes 1f necessary. It also reduces the length of the transceiver drop cable that serves that station.

BB,

The cable goes up the riser, near Station 5, to the suspended ceiling.
AR

The path continues down the hallways and intersects each target circle. The pathway ends in a small utility
room where the electrical service box is located (refer to Figure B-4).

B-2

Ry,

When the pathway has been drawn on the floor plans, the system planner then:

Measures the total length of the cable pathway. In this example, the length has been determined |

Refers to Table 3-1. From this table the planner determines that a standard coaxial cable of this

to be 172 m (564.3 ft).

length is not available. Therefore, the planner must specify the next longest coaxial cable
combination that meets the installation requirements.

In this example, that is 187 m (614 ft); in two sections, 70.2 m (230.3 ft) and 117 m (383.9 ft).
Using a new floor plan that shows only the coaxial path and station locations, the planner must:

Locate the various hardware components on the floor plan (refer to Figure B-5). This hardware
includes:

—

Terminators (2)

—
—
—

Barrel connector
Grounding components
H4000 transceivers

NOTES
The H4000 transceivers are located as close as pos-

sible to the entry points for their respective stations.

For stations 3 and 4, the transceivers are located on
each side of the riser pole to comply with the 2.5 m
(8.2 ft) spacing rules.

Now that the details of the Ethernet Local Area Network have been entered on the floor plans, the system
planner must record data that is pertinent to the station transceiver drop cable lengths. To record this
information, the planner uses the Station Transceiver Drop Cable Worksheet (a blank worksheet is
provided in Appendix D and may be copied as many times as it is needed).
The surveyor will have already started entering data on this worksheet. This data will consist of:
e
e

Station number
Riser length

Floor run

To this information, the system planner will:

Enter information about the distance from the coaxial cable to the entry points.

Total the transceiver drop cable lengths for each station.

Select the appropriate lengths of drop cables for each station.

Select the type connector heads that are needed for each cable, and specify the type of

insulation that each cable uses.

Determine the number of DELNI interconnects and DEREP repeaters together with H4000

transceivers and transceiver drop cables.

,,, i

giing

DOUBLE

PLASTERBOARD
WALL
(TYPICAL)

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Final Station Targeting

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Figure B-4

Plotting the Coaxial Cable Pathway and Hardware Locations

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Figure B-5

Second Floor Plan Showing Stations, Transceivers, and Transceiver Drop

Cables

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B-8

APPENDIX C
SAMPLE NETWORK LOG

The following Network Log entries are based on the sample floor plan presented in Appendix B. This
Sample Network Log represents only one of many possible ways in which a system planner may document
a proposed Ethernet Local Area Network.

For the purpose of cable identification, the DELNI interconnects and DEREP repeaters are treated as

stations because they require transceiver drop cables.

Included in this Appendix are samples of cable tags (refer to Figure C-1) that should be applied to the ends

of each cable section.

C-1

SAMPLE NETWORK LOG

ETHERNET COAXIAL CABLE SEGMENT

Section No. 1

117.0 m (383.9 ft)

Section No. 2

70.2 m (230.3 ft)

Segment Total

187.2 m (614.2 ft)

H4000 TRANSCEIVERS
Section No. 1

Section No. 2

Segment Total

S
e
f

NETWORK EARTH REFERENCE LOCATION
Electrical service entrance panel box at the rear of the building in the small utility room.

COAXIAL CABLE SECTION NO. 1

—

Length

117.0 m (383.9 ft)

—

Near-End Connection

Terminator

———

Near-End Location

Subfloor, in computer room

—

Far-End Connection

Section No. 2

Far-End Location

In ceiling, 5 m (16.4 ft) southwest of Station 4

H4000 TRANSCEIVER LOCATIONS
—

Station No. 5

—

Station No. 1

35 m (114.8 ft)

—

Station No. 2

50 m (164.0 ft)

—

Station No. 3

95 m (311.7 ft)

Station No. 4

100 m (328.1 ft)

5 m (16.4 ft)

GROUNDING COMPONENTS

—

None this section

COAXIAL CABLE SECTION NO. 2

—

Length

70.2 m (230.3 ft)

——

Near-End Connection

Section No. 1

—

Near-End Location

In suspended ceiling, 5 m (16.4 ft) southwest of Station 4

—

Far-End Connection

‘Terminator

Far-End Location

In ceiling, near electrical service panel box No. 1

H4000 TRANSCEIVER LOCATIONS
P

None this section.

GROUNDING COMPONENTS

Yes

—

Network Earth Reference

Electrical service entrance panel box No. 1

—

Ground Clamp Location

Terminator, at far end of Section No. 2

C-2

Date 12/3/83

COAXIAL CABLE TAG
Segment_1_

Length 70.2 m

This is O NEAR

Section_2_

IX] FAR END

OPPOSITE

END LOCATION: 5 m SW of STATION 4

OPPOSITE END CABLE: Seq.1, Sec.1 117.0 cm
NEAR END CABLE: TERM.

GROUNDING COMPONENTS HERE ?

XY __ N

PEEL-BACK
LABEL

TRANSCEIVER CABLE TAG
1 95 m
TRANSCEIVER: Sect.
STATION: 3
Length to transceiver: 10 m
Cables to transceiver: 1

Date 12/6/83

TK-10511

Figure C-1

Sample Cable Tags

ORI,

PGS,

APPENDIX D

BLANK SURVEY PLANNING FORMS

D.1 SURVEY FORMS
The Network Site Requirements Worksheet and Station Transceiver Drop Cable Worksheet are provided
to assist the surveyor in conducting the site survey. The surveyor may use as many copies of these forms as
necessary to cover all floors and or buildings on the site.

D.2 STATION TRANSCEIVER DROP CABLE WORKSHEET
Various parts of the Station Transceiver Drop Cable Worksheet are to be filled out by both the surveyor
and the system planner.

INSTRUCTIONS FOR THE SURVEYOR
Measure and record the following distances for each station.
e
e

Riser length
Floor run

INSTRUCTIONS FOR THE SYSTEM PLANNER
After the coaxial cable path has been drawn on the floor plan, fill in the following information.
e

Measure (on the floor plan) and record, for each station, the distance of the entry point to the
coaxial cable.
NOTE
The closest transceiver installation band may be up
to 1.5 m (4.9 ft) away from the closest entry point.

Total the lengths of transceiver drop cables required for each station.

Select the appropriate transceiver drop cable lengths for each station.

Select the appropriate transceiver drop cable connectors.

Select the appropriate transceiver drop cable material for each station.

Use this worksheet and Appendix A to develop a Bill of Materials.

D-1

NETWORK SITE REQUIREMENTS WORKSHEET
Date:

Time:

CUSTOMER INFORMATION
Name:

Building Address:
City:
Customer Contact/Title:

State:

Zip:
Phone:
Phone:

Facility Manager:
IL.

BUILDING INFORMATION
Customer-Owned Facility: Yes
Lease Restrictions: Yes
Describe Lease Restrictions:

No
No

Number of Floors:

Raised Floors: Yes
No
Dimensions:
Ceiling Type: Spline Lock
Suspended
Plaster
Plasterboard
“Above Ceiling Environmental AirspaceTM: Yes
No
Interior Walls: Solid
Hollow
IIL.

NETWORK SIZE REQUIREMENTS

Number of Floors Having Stations:
Number of Planned Stations:

Future:
Future:

NOTE: The following information should be marked on the floor plan and checked off when
completed.
|
Location of Stations:
Location of Entry Points:
Location of; Interfloor
Raised Floor
Suspended Ceiling Risers
Locations of Potential Network Earth Reference Ground:
IV.

INSTALLATION REQUIREMENTS

Target Installation Completion Date:
Installation Managed By: DIGITAL

Customer

NOTE: If the installation is for a multifloor or multibuilding site, use extra copies of this form.
Attach floor plans and drawings and route to the system planner.
R

STATION TRANSCEIVER DROP CABLE WORKSHEET

STATION NO.

—

FLOOR RUN (M)
RISER LENGTH (M)
ENTRY POINT DISTANCE (M)
STATION RISE + H4000

_
——

ALLOWANCE

4AM|

TOTAL (M)

STATION NO.
FLOOR RUN (M)

RISER LENGTH (M)

—

STATION RISE + H4000
ALLOWANCE

TOTAL (M)

ENTRY POINT DISTANCE (M)

STATION NO.

—

amM
S—

FLOOR RUN (M)
RISER LENGTH (M)
ENTRY POINT DISTANCE (M)

N
____

ALLOWANCE

TOTAL (M)

—

STATION RISE + H4000

STATION NO.
FLOOR RUN (M)

RISER LENGTH (M)

ENTRY POINT DISTANCE (M)
STATION RISE + H4000

—

___

ALLOWANCE

TOTAL (M)

D-3

SITE SURVEY AND DESIGN CHECKLIST

Meet with the facility manager. Evaluate the facility and complete the Network Site Requirements Worksheet.

Obtain floor plans of all floors and for all buildings where the Ethernet Local Area Network will
be installed.
Identify all station locations, current and future, on the floor plans.
W

Complete Station Transceiver Drop Cable Worksheet foxn' all stations.
Y

Examine each station location for possible cable installation methods; measure clearances.

Examine the ventilation system for environmental airspace cable installation.
Have a qualified electrician identify and measure the voltages at possible network earth reference
ground locations.

Obtain all permits, licenses, and inspections required by local codes.
Submit the marked-up floor plans, worksheets, and preliminary station count to the system
planner.
Copy and distribute as appropriate:

Original floor plan(s)

Network Site Requirements Worksheet(s)
Station Transceiver Drop Cable Worksheet(s)
Locate all DELNI interconnects, current and future, on the floor plans.
Locate all DEREP repeaters, current and future, on the floor plans.

NETWORK COMPONENT ORDER WORKSHEET
(Sample Only)

Using the building floor plans, summarize the required network components.
Quantity

ETHERNET COAXIAL CABLE
Coaxial Cable Sections
FEP Cables

BNE2A-MA [23.4 m (76.8 ft)]
BNE2A-MB [70.2 m (230.3 ft)]
BNE2A-MC [117.0 m (383.9 ft)]
BNE2A-ME [500.0 m (1640.5 ft)]
PVC Cables

BNE3A-MA [23.4 m (76.8 ft)]
BNE3A-MB [70.2 m (230.3 ft)]
BNE3A-MC [117.0 m (383.9 ft)]
BNE3A-ME [500.0 m (1640.5 ft)]
TRANSCEIVER DROP CABLES
PVC Drop Cables

(Straight Connectors)

BNE3A-05 [5S m (16.4 ft)]
BNE3A-10 [10 m (32.8 ft)]
BNE3A-20 [20 m (65.6 ft)]
BNE3A-40 [40 m (131.2 ft)]
PVC Drop Cables

(Right-Angle Connectors)
BNE3B-05 [5 m (16.4 ft)]
BNE3B-10 [10 m (32.8 ft)]
BNE3B-20 [20 m (65.6 ft)]
BNE3B-40 [40 m (131.2 ft)]

FEP Drop Cables
(Straight Connectors)

BNE3C-05 [5 m (16.4 ft)]
BNE3C-10 [10 m (32.8 ft)]
BNE3C-20 [20 m (65.6 ft)]
BRNE3C-40 [40 m (131.2 ft)]

Unit Price

Price

NETWORK COMPONENT ORDER WORKSHEET (CONT)
Quantity
FEP Drop Cables

Unit Price

Price
P

(Right-Angle Connectors)
BNE3D-05 [5S m (16.4 ft)]
BNE3D-10 [10 m (32.8 ft)]
BNE3D-20 [20 m (65.6 ft)]
BNE3D-40 [40 m (131.2 ft)]
PVC Office Drop Cables

(Straight Connectors)
BNE4A-02 [2 m (6.6 ft)]
BNE4A-05 [S m (16.4 f1)]

PVC Office Drop Cables
(Right-Angle Connectors)
BNE4B-02 [2 m (6.6 ft)]
BNE4B-05 [5 m (16.4 ft)]
Fiber-Optic Cable

BNE25B-60 60 m (196.9 ft)
BNE25B-90 90 m (295.3 ft)
BNE25B-AS5 150 m (492.1 ft)
BNE25B-C0 300 m (984.3 ft)
BNE25B-E0 500 m (1640.4 ft)
BNE25B-H5 750 m (2460.8 ft)
BNE25B-L0 1000 m (3281.0 ft)

COAXIAL CABLE ACCESSORIES
Barrel Connector
P/N 12-19817-01

Terminator
P/N 12-19816-01

Ground Clamp
P/N 12-21766-01

NETWORK COMPONENT ORDER WORKSHEET (CONT)

TRANSCEIVER INSTALLATION KIT

With Drill

P/N H4090-KA
Without Drill

P/N H4090-KB
TRANSCEIVER (TAP)
Coaxial Cable Tap
P/N H4000

LOCAL NETWORK INTERCONNECT
(8 Device Interconnect)
P/N DELNI-AA

Local Repeater
P/N DEREP-AA

Remote Repeater

FIBER-OPTIC PULLING DEVICE

Pulling Device

P/N 033-29-1015
Swivel
P/N 203-08001

REPAIR COMPONENTS

Coaxial Cable
Male Type N Connector
P/N H4056

Coaxial Cable Cutter
P/N 29-24667

Quantity

Unit Price

Price

NETWORK COMPONENT ORDER WORKSHEET (CONT)
Quantity

Unit Price

Price

Coaxial Cable Stripper
P/N 29-24668
T

Connector Crimp Tool and Die Set
P/N 29-24662
P/N 29-24663

Transceiver Drop Cable

Straight Connector Kit
P/N H4054
Right-Angle Connector Kit
P/N H4055

D-Connector Pin Crimp Tool
AMP P/N 90302-1
Cable Ferrule Crimp Tool and Die Set
AMP P/N 91239-7
SO

APPENDIX E

DELNI LOCAL

NETWORK INTERCONNECT

E.1

INTRODUCTION

E.2

GLOBAL MODE

The DELNI Local Network Interconnect is used to connect multiple host systems and communications
servers in a network. There are two modes of operations: global and local.
Global mode is used when the DELNI interconnect is connected to an H4000 transceiver on an Ethernet
coaxial cable. This Ethernet Installation Guide has exclusively discussed this type of network interconnection. It is also used for cascaded mode as discussed in Section E.3.
E.3 LOCAL MODE

The local mode is used when the DELNI interconnect is not connected to the Ethernet coaxial cable. In
this mode of operation, the DELNI interconnect forms its own Ethernet network. The local mode of the
DELNI Local Network Interconnect is shown in Figure E-1.

As can be seen in Figure E-1, up to eight host systems can be connected to a single DELNI interconnect. If
all host systems are within a 40 m (131.2 ft) radius circle, a single DELNI interconnect can provide the
interconnection, and an Ethernet coaxial cable is not required.
The DELNI Local Network Interconnect, local mode, may be expanded by connecting a combination of
DELNI interconnects and devices to the top DELNI interconnect. By cascading DELNI interconnects in
this manner (refer to Figure E-2), it is possible to create a very powerful, standalone Ethernet network
with many nodes. However, a cascaded network must not extend more than 90 m (295.3 ft).
NOTE

It is possible to have up to eight DELNI interconnects in the second layer. However, Digital Equipment Corporation recommends that for networks of
this size, connection to the Ethernet coaxial cable
should be considered.
If DELNI interconnects are cascaded, the top
DELNI interconnect cannot connect to an Ethernet
coaxial cable. A maximum of two layers of DELNI
interconnects are permitted, with the second layer of
DELNI interconnects operating in the global mode.

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