Allied AT-FS238A/1-60 User Manual

AT-FS238a/1
AT-FS238b/1
AT-FS238a/2
AT-FS238b/2

Bridging Converters

Installation Guide

PN 613-50431-00 Rev B

Copyright  2003 Allied Telesyn, Inc.
960 Stewart Drive, Suite B, Sunnyvale, CA 94085, USA

All rights reserved. No part of this publication may be reproduced without prior
written permission from Allied Telesyn, Inc.

Ethernet is a registered trademark of Xerox Corporation. All other product names,
company names, logos or other designations mentioned herein are trademarks or
registered trademarks of their respective owners.

Allied Telesyn, Inc. reserves the right to make changes in specifications and other
information contained in this document without prior written notice. The information
provided herein is subject to change without notice. In no event shall Allied Telesyn,
Inc. be liable for any incidental, special, indirect, or consequential damages whatsoever,
including but not limited to lost profits, arising out of or related to this manual or the
information contained herein, even if Allied Telesyn, Inc. has been advised of, known, or
should have known, the possibility of such damages.

Electrical Safety and Emission Compliance Statement

Standards: This product meets the following standards.

U.S. Federal Communications Commission

Declaration Of Conformity

Manufacturer Name: Allied Telesyn, Inc.
Manufacturer Address: 960 Stewart Drive, Suite B

Manufacturer Telephone: [phone]
Declares that the product: Bridging Converter
Model Numbers: AT-FS238a/1, AT-FS238b/1,

This product complies with FCC Part 15B, Class B Limits:
This device complies with part 15 of the FCC Rules. Operation is subject

to the following two conditions: (1) This device must not cause harmful
interference, and (2) this device must accept any interference received,
including interference that may cause undesired operation.

Radiated Energy

Note: This equipment has been tested and found to comply with the limits
for a Class B digital device pursuant to Part 15 of FCC Rules. These
limits are designed to provide reasonable protection against harmful
interference in a residential installation. This equipment generates, uses
and can radiate radio frequency energy and, if not installed and used in
accordance with instructions, may cause harmful interference to radio or
television reception, which can be determined by turning the equipment
off and on. The user is encouraged to try to correct the interference by one
or more of the following measures:

- Reorient or relocate the receiving antenna.

- Increase the separation between the equipment and the receiver.

- Connect the equipment into an outlet on a circuit different from that to
which the receiver is connected.

- Consult the dealer or an experienced radio/TV technician for help.

Changes and modifications not expressly approved by the manufacturer
or registrant of this equipment can void your authority to operate this
equipment under Federal Communications Commission rules.

Sunnyvale, CA 94085, USA

AT-FS238a/2, AT-FS238b/2

Industry Canada

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

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

iii

Electrical Safety and Emission Compliance Statement

RFI Emission FCC Class B, EN55022 Class B,

Warning: In a domestic environment this product may cause radio

interference in which case the user may be required to take adequate
measures.

Immunity EN55024
Warning: This product requires shielded cables to comply with emission

and immunity standards. If it is used with unshielded cables, the user may
be required to take measures to correct the interference problem at th eir own
expense.

Electrical Safety EN60950 (TUV), UL60950 (
Laser EN60825
Warning Class 1 Laser product.
Warning Do not stare into the Laser beam.

At time of installation, the Fiber Optic Lasers comply with FDA Radiation
Performance Standard 21CFR Subchapter J, applicable at date of
manufacture.

This is a “Class 1 LED Product”.
Important: Appendix B contains translated safety statements for installing

this equipment. When you see the
safety statement in your language.

Wichtig: Anhang B enthält übersetzte Sicherheitshinweise für die
Installation dieses Geräts. Wenn Sie
den übersetzten Sicherheitshinweis in Ihrer Sprache nach.

Vigtigt: Tillæg B indeholder oversatte sikkerhedsadvarsler, der vedrører
installation af dette udstyr. Når De ser symbolet
B og finde de oversatte sikkerhedsadvarsler i Deres eget sprog.

Belangrijk: Appendix B bevat vertaalde veiligheidsopmerkingen voor het
installeren van deze apparatuur. Wanneer u de
Appendix B voor vertaalde veiligheidsinstructies in uw taal.

Important: L'annexe B contient les instructions de sécurité relatives à
l'installation de cet équipement. Lorsque vous voyez le symbole
reportez-vous à l'annexe B pour consulter la traduction de ces instructions
dans votre langue.

Tärkeää: Liite B sisältää tämän laitteen asentamiseen liittyvät käännetyt
turvaohjeet. Kun näet
liitteestä B.

Importante: l’Appendice B contiene avvisi di sicurezza tradotti per
l’installazione di questa apparecchiatura. Il simbolo
l’Appendice B per l’avviso di sicurezza nella propria lingua.

Viktig: Tillegg B inneholder oversatt sikke rhetsinformasjon for installering
av dette utstyret. Når du ser
oversatte sikkerhetsinformasjonen på ønsket språk.

Importante: O Anexo B contém advertências de segurança traduzidas para
instalar este equipamento. Quando vir o símbolo
segurança traduzida no seu idioma no Anexo B.





2

4



-symbolin, katso käännettyä turvaohjetta

VCCI Class B, C-TICK

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3



6



7



8



9

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, go to Appendix B for the translated

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,

iv

AT-FS238a/x and AT-FS238b/x Series Installation Guide

Importante: El Apéndice B contiene mensajes de seguridad traducidos
para la instalación de este equipo. Cuando vea el símbolo
Apéndice B para ver el mensaje de seguridad traducido a su idioma.

Obs! Bilaga B innehåller översatta säkerhetsmeddelanden avseende
installationen av denna utrustning. När du ser
för att läsa det översatta säkerhetsmeddelandet på ditt språk.





, vaya al

, skall du gå till Bilaga B

v

Table of Contents

Electrical Safety and Emission Compliance Statement ......................iii

Welcome to Allied Telesyn .......................................................................... ix

Where to Find Web-based Guides ................................................................... ix

Document Conventions .................................................................................... ix

Contacting Allied Telesyn ................................................................................. x

Online Support ........................................................................................... x

E-mail and Telephone Support .................................................................. x

Returning Products .................................................................................... x

For Sales or Corporate Information .......................................................... x

Chapter 1

Overview .......................................................................................................... 1

Introduction ....................................................................................................... 2

Location of Components .................................................................................... 6

External Power Supply ..................................................................................... 9

12VDC Power Supply ................................................................................. 9

12-50VDC Power Supply ............................................................................ 9

Key Features .................................................................................................... 10

Status LEDs ..................................................................................................... 11

Twisted Pair Port ............................................................................................. 12

Port Speed ................................................................................................. 12

Duplex Mode ............................................................................................. 12

Auto MDI/MDI-X ...................................................................................... 13

Fiber Optic Port ............................................................................................... 14

Port Speed ................................................................................................. 14

Duplex Mode ............................................................................................. 14

Mode Selection Button .................................................................................... 15

Link Test ................................................................................................... 15

MissingLink .............................................................................................. 15

Smart MissingLink .................................................................................. 16

Bridging Converter Performance .................................................................... 17

DIP Switches .................................................................................................... 17

MAC Address Table ......................................................................................... 17

Store and Forward ........................................................................................... 18

vii

Table of Contents

Chapter 2

Installing the Bridging Converter ........................................................... 19

Verifying Package Contents ............................................................................ 19

Planning the Installation ................................................................................20

Selecting a Site .........................................................................................21

Reviewing Safety Guidelines ...................................................................22

Installing the Bridging Converter ..................................................................23

Connecting a 12VDC Powered Unit ................................................................ 27

Wiring and Connecting a 12-50VDC Powered Unit .......................................28

Warranty Registration .................................................................................... 32

Chapter 3

Troubleshooting ........................................................................................... 33

Appendix A

Technical Specifications ............................................................................37

Physical ............................................................................................................ 37

Environmental .................................................................................................37

Electrical Rating .............................................................................................. 37

Agency Certifications ....................................................................................... 38

Fiber Optic Port Specifications .......................................................................39

RJ-45 Pinout Assignments ..............................................................................41

Appendix B

Translated Safety and Emission Information .......................................43

viii

Welcome to Allied Telesyn

This guide contains instructions on how to install the AT-FS238a/x and
AT-FS238b/x Series Bridging Converters.

Where to Find Web-based Guides

The Allied Telesyn web site at www.alliedtelesyn.com offers you an easy
way to access the most recent documentation, software, and technical
information for all of our products. For product guides, select “Support &
Services” from our web site.

Document Conventions

This guide uses the following conventions:

Note

Notes provides additional information.

Caution

Cautions indicate that performing or omitting a specific action may
result in equipment damage or loss of data.

Warning

Warnings indicates that performing or omitting a specific action may
result in bodily injury.

ix

Welcome to Allied Telesyn

Contacting Allied Telesyn

This section provides Allied Telesyn contact information for technical support
as well as sales or corporate information.

Online Support

You can request technical support online by accessing the Allied Telesyn
Knowledge Base from the following web site: http://kb.alliedtelesyn.com.
You can use the Knowledge Base to submit questions to our technical support
staff and review answers to previously asked questions.

E-mail and Telephone Support

For Technical Support via e-mail or telephone, refer to the Support & Services
section of the Allied Telesyn web site: http://www.alliedtelesyn.com.

Returning Products

Products for return or repair must first be assigned a Return Materials
Authorization (RMA) number. A product sent to Allied Telesyn without a
RMA number will be returned to the sender at the sender’s expense.

To obtain a RMA number, contact Allied Telesyn’s Technical Support at our
web site: http://www.alliedtelesyn.com.

For Sales or Corporate Information

You can contact Allied Telesyn for sales or corporate information at our web
site: http://www.alliedtelesyn.com. To find the contact information for your
country, select “Contact Us” then “Worldwide Contacts.”

x

Chapter 1

Overview

The AT-FS238a/x and AT-FS238b/x Series Bridging Converters include the
following models:

❑ AT-FS238a/1

❑ AT-FS238b/1

The AT-FS238a/x and AT-FS238b/x Series Bridging Converters are designed
to convert Fast Ethernet data between twisted pair cabling and fiber optic
cabling. These converters serve the following functions:

❑ AT-FS238a/2

❑ AT-FS238b/2

❑ Dividing your network into smaller units.

❑ Maximizing your existing fiber network by providing full-duplex

operation over a single fiber strand.

❑ Interconnecting network devices that are physical far apart.

The converter’s fiber optic port is IEEE 802.3ah-compliant and operates at
100 Mbps, while the twisted pair port operates at 10 Mbps or 100 Mbps. The
fiber optic port has a simplex SC connector and an operating distance of 15
kilometers (9.4 miles) or 40 kilometers (24.8 miles), depending on the model.
The twisted pair port has an RJ-45 connector with a maximum operating
distance of 100 meters (328 feet). Both ports feature half- or full-duplex mode
operation.

AT-FS238a/x and AT-FS238b/x Series Bridging Converters can be installed on
a desktop or in an AT-MCR12 chassis. These bridging converters are easy to
install and do not require software configuration or management.

1

Overview

Introduction

The fiber optic port on the bridging converter offers an important advantage
over fiber optic ports commonly found on Fast Ethernet equipment. It can
simultaneously transmit and receive Ethernet data for full-duplex operation
over a single fiber strand. In comparison, a conventional fiber optic port
requires two fiber strands for full-duplex operation.

In a conventional fiber optic installation, each fiber optic strand carries only
one data stream at a time and in only one direction, as illustrated in Figure 1.

Fiber Strand

Figure 1 Data Stream on a Single Fiber Strand

The data stream is transmitted at a specific wavelength, typically 850
nanometers (nm), 1310 nm, or 1550 nm. These wavelengths are known for
their low attenuation.

Full-duplex operation in a conventional fiber installation involves two
separate fiber strands, one for transmitting data and another for receiving
data, as illustrated in Figure 2. Both data streams are transmitted at the
same wavelength, but since each is on a separate strand, the signals remain
separate.

Figure 2 Full-duplex Operation on a Conventional Fiber Optic Installation

Data Stream

λ1

λ1

λ2

The fiber optic port on the bridging converters combines two data streams
onto one fiber optic strand. This allows you to use more of the bandwidth
inherent in fiber cable and so significantly increase the efficiency of your
existing fiber optic backbone network.

2

AT-FS238a/x and AT-FS238b/x Series Installation Guide

The port uses a different wavelength for each data stream. Since each data
stream is transmitted at a different wavelength (1310 nm and 1550 nm), the
signals remain separate. This maintains data separation and security.
Additionally, a converter can receive and transmit data on the same fiber
strand. This allows for full-duplex operation with just one strand, as
illustrated in Figure 3.

λ1
λ2

Figure 3 Two Data Streams on a Fiber Strand

The fiber optic port makes these bridging converters extremely useful in
situations where a conventional fiber optic backbone network no longer has
sufficient bandwidth to handle the data traffic. This problem has become a
common occurrence on many networks due to the rapid growth of data traffic
from sources such as voice over IP, multimedia applications, video
conferencing, and the Internet.

The traditional solution to increasing bandwidth on a fiber optic backbone has
been to install additional fiber optic cable. But this can be an extremely costly
and time-consuming process. Additionally, conventional fiber optic
installations are unable to use the extremely large bandwidth capacity that is
inherent in fiber optic cable.

3

Overview

This is illustrated in Figure 4 where one AT-FS238a/1 converter and one AT­FS238b/1 converter are used to interconnect two subnetworks located at
different campuses 15 km (9.3 mi) apart. This type of topology is commonly
referred to as Back-to-Back. The AT-FS238a/1 converter at Campus 1 sends
data at 1310 nm and receives at 1550 nm while the AT-FS238b/1 converter at
Campus 2 receives data at 1310 nm and sends at 1550 nm.

Campus 1 Campus 2

15 km (9.3 mi)

SINGLE MODE 1310TX/1550RX

AT-FS238a/1

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AT-FS238b/1

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= Single Fiber Strand
= Twisted Pair Cable

Figure 4 Back-to-Back Network Topology

4

AT-FS238a/x and AT-FS238b/x Series Installation Guide

Since the fiber optic port on the bridging converters is IEEE 802-3ah­compliant, these devices can also be used by voice and data service providers
to provide service to the home. This type of topology is referred to as Fiber-to­the-Home. In Figure 5, an IEEE 802.3ah-compliant device at the provider’s
central office sends data to an AT-FS238a/2 converter located at a home on a
single fiber strand. The converter then transmits the data to a router gateway
located inside the home via the twisted pair port. The router gateway, in turn,
provides communications to a phone, a fax machine, and a computer for
Internet access.

Connected to an
IEEE 802.3ah-compliant
device at provider's
central office

40 km (24.8 mi)

SINGLE MODE 1310TX/1550RX

FS238a/2
Bridging Converter

Router Gateway

= Single Fiber Strand

= Twisted Pair Cable

Figure 5 Fiber-to-the-Home Topology

Note

The fiber optic ports on the AT-FS238a/x and AT-FS238b/x Series
converters are IEEE 802.3ah-compliant and must be connected to a
device that meets the same compliant requirement.

5

Overview

Location of Components

Figure 6 illustrates the front panel of the AT-FS238a/x Series Bridging
Converter.

Twisted Pair PortFiber Optic Port

SINGLE MODE 1310TX/1550RX

Figure 6 AT-FS238a/x Series Front Panel (AT-FS238a/1 Model)

Figure 7 illustrates the front panel of the AT-FS238b/x Series Bridging
Converter.

SINGLE MODE 1550TX/1310RX

6

AT-FS238b/1

Figure 7 AT-FS238b/x Series Front Panel (AT-FS238b/1 Model)

AT-FS238a/x and AT-FS238b/x Series Installation Guide

The back panel of the AT-FS238a/x and AT-FS238b/x Series Bridging
Converters features a DC power connector and DIP switches for manually
configuring the ports.

Note

The AT-FS238a/x and AT-FS238b/x Bridging Converters are offered
with two different DC power connectors: 12VDC and 12-50VDC.

Figure 8 illustrates the back panel of the AT-FS238a/x and AT-FS238b/x
Series Bridging Converters with a 12VDC power connector.

DIP Switches

PORT

1222

21 34

DUPLEX

12 V D C

SPEED
(Mbps)

AUTO

MODE

HALF
FULL

NEG

OFF
ON

10
100

12VDC Receptacle Connector

DC Polarity Symbols

Figure 8 Back Panel of the AT-FS238a/x and AT-FS238b/x Series Bridging Converters

(12VDC Power Connector)

Figure 9 illustrates the back panel of the AT-FS238a/x and AT-FS238b/x
Series Bridging Converters with a 12-50VDC, 3-prong power connector.

DIP Switches

PORT

1222

21 34

DUPLEX

12-50VDC

12-50VDC 3-Prong Receptacle Connector

SPEED
(Mbps)

10
100

DC Polarity Symbols

MODE

HALF
FULL

AUTO

NEG

OFF
ON

Figure 9 Back Panel of the AT-FS238a/x and AT-FS238b/x Series Bridging Converters

(12-50VDC, 3-Prong Power Connector)

7

Overview

Table 1 lists the maximum operating distances for the bridging converters.

Table 1 Maximum Operating Distances

100Base-FX 10Base-T/100Base-TX

Model

Connector

Maximum Operating

Distance

1

Connector

Maximum Operating

Distance

2

AT-FS238a/1

Simplex SC15 km (9.3 mi) RJ-45 100 m (328 ft)

AT-FS238b/1

AT-FS238a/2

Simplex SC40 km (24.8 mi) RJ-45 100 m (328 ft)

AT-FS238b/2

1. Maximum distance for 100 Mbps optical datalinks is dependent on the following factors: type of optical fiber,
duplex mode of both end-nodes, and maximum optical loss budget for each of the optical fiber at the operating
optical wavelength.

2. Maximum distance can only be obtained when the UTP/STP cabling is installed and verified to TIA/EIA 568A
Commercial Building Telecommunications Cabling Standard.

8

AT-FS238a/x and AT-FS238b/x Series Installation Guide

External Power Supply

12VDC Power Supply

The 12VDC-version bridging converters come with the AC/DC power adapter
illustrated in Figure 10. This is an approved safety compliant AC power
adapter for the 100 and 240V AC versions with an unregulated output of
12VDC.

Figure 10 AC/DC Power Adapter for the 12VDC Version Bridging Converter

12-50VDC Power Supply

The 12-50VDC-version bridging converters do not come with a power supply.
It must be purchased separately. Approved power supplies include:

❑ An AT-PWR237 power adapter (12V or 15V output). This power

adapter can be ordered separately from your Allied Telesyn sales
representative.

❑ A regulated power supply (SELV power source per IEC 60950) - rated

minimum 12-50VDC, 0.5A.

Note

Use only power sources that are UL Listed (QQGQ or EPBU), TUV
Licensed, or other Safety Agencies approved, and that are suitable for
country of use.

Figure 11 illustrates the power connector included with the 12-50VDC-version
bridging converter. This connector is used to wire and connect a 12-50VDC­version bridging converter.

Figure 11 Power Connector for the 12-50VDC Version Bridging Converter

9

Overview

Key Features

The AT-FS238a/x and AT-FS238b/x Series Bridging Converters have the
following features:

❑ LEDs for unit and port status

❑ Auto MDI/MDI-X

❑ Mode selection button that toggles between Link Test, MissingLink

and Smart MissingLink

❑ DIP switches for configuring the ports

❑ Half- or full-duplex operation on both ports

❑ RJ-45 twisted pair connector

❑ Simplex SC fiber optic connector

❑ Data packet forwarding and filtering at full wire speed (10 Mbps to

100 Mbps, and 100 Mbps to 100 Mbps)

❑ Store and forward switching mode

❑ Automatic address learning and aging

❑ IEEE 802.3u compliant Auto-Negotiation

❑ For use on a desktop or in an AT-MCR12 chassis

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AT-FS238a/x and AT-FS238b/x Series Installation Guide

Status LEDs

Table 2 defines the LEDs for the bridging converters.

Table 2 Status LEDs

LED Color Description

PWR Green Power is applied to the unit.

AUTO NEG Green

OFF

100M Green

OFF

LNK Green

Blinking

FD/COL Green

OFF

Blinking

Mode Status

ML Green MissingLink is enabled.

SML Green Smart MissingLink is enabled.

LT Green Link Test is enabled.

Auto-Negotiation on the twisted pair port is enabled.

Auto-Negotiation on the twisted pair port is disabled.

The twisted pair port is operating at 100 Mbps.

The twisted pair port is operating at 10 Mbps.

A valid link has been established on the port.

Data is being received or transmitted on the port.

The bridging converter is operating in full-duplex mode.

The bridging converter is operating in half-duplex mode.

Collisions are detected on the port.

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Overview

Twisted Pair Port

The AT-FS238a/x and AT-FS238b/x Series Bridging Converters have one
10Base-T/100Base-TX twisted pair port. The twisted pair port features a
RJ-45 connector.

Port Speed

The twisted pair port is compliant with the 10Base-T and 100Base-TX
standards and is capable of either 10 Mbps or 100 Mbps operation. You can set
the port speed manually or, since the port is IEEE 802.3u Auto-Negotiation
compliant, you can let the bridging converter set the port speed automatically.
With Auto-Negotiation, the speed of the port is set automatically by the
bridging converter after it determines the speed of the end-node connected to
the port. Auto-Negotiation is designed to ensure that the port on the bridging
converter and the end-node are operating at the same speed and that they are
communicating at the highest possible common speed of the devices.

Duplex Mode

Duplex mode refers to how an end-node receives and transmits data. If an
end-node can receive or transmit data, but not both simultaneously, the end­node is operating in what is referred to as half-duplex mode. If an end-node
can both receive and transmit data simultaneously, the end-node is said to be
operating in full-duplex mode. Naturally, an end-node capable of operating in
full-duplex can handle data much faster than an end-node that can only
operate in half-duplex mode.

The twisted pair port on the AT-FS238a/x and AT-FS238b/x Series Bridging
Converters can operate in either half-or full-duplex mode. It is IEEE 802.3u­compliant and uses Auto-Negotiation to set the duplex mode setting for you
automatically. If desired, Auto-Negotiation can be disabled and you can set
the duplex mode manually.

Note

In order for a twisted pair port on the AT-FS238a/x and AT-FS238b/x
Series Bridging Converters to successfully Auto-Negotiate its duplex
mode with an end-node, the end-node should also be using Auto­Negotiation. Otherwise, a duplex mode mismatch can occur. The twisted
pair port, using Auto-Negotiation, will default to half-duplex if it detects
that the end-node is not using Auto-Negotiation. This will result in a
mismatch if the end-node is operating at a fixed duplex mode of full­duplex.

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AT-FS238a/x and AT-FS238b/x Series Installation Guide

Auto MDI/MDI-X

An RJ-45 twisted pair port on a 10 Mbps or 100 Mbps Ethernet network
device can have one of two possible wiring configurations: MDI or MDI-X. The
RJ-45 port on a PC, router, or bridge is typically wired as MDI, while the
twisted pair port on a bridging converter or hub is usually MDI-X.

When the twisted pair port on the AT-FS238a/x and AT-FS238b/x Series
converters is set to Auto-Negotiation, the port features automatic MDI/MDI­X. The RJ-45 port automatically determines the configuration of the port on
the end-node and then configures itself appropriately. This features allows
you to use either a straight-through or crossover cable when connecting an
end-node to the twisted pair port.

When the port on the AT-FS238a/x or AT-FS238b/x Series converter is not set
to Auto-Negotiation, the port defaults to MDI-X. To connect to an end-node
that has the same wiring configuration, such as MDI-X to MDI-X, you would
use a crossover twisted pair cable. To connect to an end-node that has
different port wiring configuration, such as MDI to MDI-X, you would use a
straight-through cable.

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