Allied Telesis AT-FS201 Series User manual

AT-FS201,
AT-FS202,
AT-FS203
Fast Ethernet Switches
Installation Guide
PN 613-10761-00 Rev. A

Copyright 1998 Allied Telesyn International, Corp.
950 Kifer Road, Sunnyvale CA 94086 USA
All rights reserved. No part of this publication may be reproduced without prior written permission
from Allied TelesynInternational, Corp.
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 International,Corp. reserves the right to make changes in specifications andother
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 International, Corp. 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 International, Corp. has been advised of, known, or should have known, the
possibility of such damages.

iii
Electrical Safety and Installation
Requirements
STANDARDS: This product meets the following standards
RFI Emission EN55022 Class A
WARNING:In a domesticenvironment thisproduct maycause radio interference in which case the user may be
required to take adequatemeasures.
Immunity EN50082-1
WARNING: This productrequires shielded cables to comply with emission and immunity standards. If it is used
withunshieldedcables,theusermayberequiredtotakemeasurestocorrecttheinterferenceproblemattheirown
expense.
Electrical Safety EN60950, UL1950, CSA 950
Laser EN60825
Warning Class 1 Laser product.
Warning Do not stare into the Laser beam.
Attimeofinstallation,theFiberOpticLaserscomplywithFDARadiationPerformanceStandard21CFRSubchapter
J, applicable at date of manufacture.
SAFETY
LIGHTNING DANGER
DANGER: DO NOT WORK on equipment or CABLES during periods of LIGHTNING ACTIVITY.
DO NOT BLOCK AIR VENTS
Power to the hub must be sourced only from the adapter.
USA/CANADA
Use a UL Listed/CSA Certified AC adapter of DC 12V, 500mA.
EUROPE - EU
Use TÜV licensed AC adapter ofDC 12V, 500mA.
UK
Use a UK Safety Approved AC adapter of DC 12V, minimum 500mA.
OPERATING TEMPERATURE
This product is designed for a maximum ambient temperature of 40 degrees C.
ALL COUNTRIES: Install product in accordance with local and National Electrical Codes.
U.S. Federal Communications Commission
RADIATED ENERGY
Note: This equipment has been tested and found to comply with the limits for a Class A digital device pursuant to
Part 15 of FCC Rules. These limits are designed to provide reasonable protection against harmful interference
whenthe equipment isoperatedin a commercial environment. This equipment generates, uses,and can radiate
radio frequency energyand, if not installed and used in accordance with this instruction manual, may cause
harmful interference toradio communications. Operation of thisequipmentin a residential area is likely to cause
harmful interference in which case theuser will be required to correct the interference at his own expense.
Note: Modifications or changes not expressly approved of by the manufacturer or the FCC, can void your right to
operate this equipment.
Industry Canada
This Class A digital apparatus meets all requirements of the Canadian Interference-Causing Equipment
Regulations.
Cet appareil numérique de la classe A respecte toutes les exigences du Règlement sur le matériel brouilleur du
Canada.

Electrical Safety and Installation Requirements
iv
NORMEN: Dieses Produkt erfüllt dieAnforderungen der nachfolgenden Normen.
Hochfrequenzstörung EN55022 Klasse A
WARNUNG:BeiVerwendungzuHausekanndiesesProduktFunkstörungenhervorrufen.IndiesemFallmüßteder
Anwender angemessene Gegenmaßnahmen ergreifen.
Störsicherheit EN50082-1
ACHTUNG: Für dieses Produkt sind abgeschirmte Kabel erforderlich, damit den Richtlinien für Emission und
Interferenzschutzentsprochenwird. Falls das Produkt mit nicht abgeschirmtenKabeln verwendet wird,können
weitergehende Maßnahmen für die Korrektur von Interferenzproblemen auf Kosten des Benutzers notwendig
werden.
Elektrische Sicherheit EN60950, UL1950, CSA 950
Laser EN60825
Warnung Laserprodukt derKlasse 1.
Warnung Nicht direkt in den Strahl blicken.
SICHERHEIT
GEFAHR DURCH BLITZSCHLAG
GEFAHR: Keine Arbeiten am Gerät oder an den Kabeln währendeines Gewitters ausführen
ENTLÜFTUNGSÖFFNUNGENNICHT VERSPERREN
Der Buchse darf nur aus dem Adapter Strom zugeführt werden.
EUROPE - EU
Gebrauchen Sie einen von TÜV zugelassenen Wechselstromadapter für Gleichstrom 12 V, 500 mA.
BETRIEBSTEMPERATUR
Dieses Produkt wurde für den Betrieb in einer Umgebungstemperatur von nicht mehr als 40° C entworfen.
ALLE LÄNDER: Installation muß örtlichen undnationalen elektrischen Vorschriften entsprechen.
STANDARDER: Dette produkt tilfredsstiller de følgende standarder.
Radiofrekvens forstyrrelsesemission EN55022 Klasse A
ADVARSEL: I et hjemligt miljø kunne dette produktforårsage radio forstyrrelse. Bliver det tilfældet, påkræves
brugeren muligvis at tage tilstrækkelige foranstaltninger.
Immunitet EN50082-1
ADVARSEL: Dette produktskal bruges med afskærmede kablerfor at overholde bestemmelserne vedrørende
udstråling ogstøjimmunitet. Hvis det bruges med uafskærmede kabler, kan det blive påkrævetaf brugeren at
korrigere interferensproblemer for egen regning.
Elektrisk sikkerhed. EN60950, UL1950, CSA 950
Laser EN60825
Advarsel Laserprodukt av klasse 1.
Advarsel Stirr ikke på strålen.
SIKKERHED
FARE UNDER UVEJR
FARE: UNDLAD at arbejde på udstyr eller KABLER i perioder med LYNAKTIVITET.
VENTILATIONSÅBNINGERNE MÅ IKKE BLOKERES
Strømforsyningen til apparatet må udelukkende tages fra tilpasningstransformatoren.
EUROPE - EU
Brug kun TÜV godkendt vekselstrømstransformator på 12 V jævnstrøm, 500 mA.
BETJENINGSTEMPERATUR
Dette apparater konstrueret til en omgivende temperatur på maksimum 40 grader C.
ALLE LANDE:Installationafproduktetskalskeioverensstemmelsemedlokalognationallovgivningforelektriske
installationer.

AT-FS201, AT-FS202 and AT-FS203 Installation Guide
v
EISEN: Dit product voldoet aan devolgende eisen.
RFI Emissie EN55022 Klasse A
WAARSCHUWING:Binnenshuiskanditproductradiostoringveroorzaken,inwelkgevaldegebruikerverplichtkan
worden om gepastemaatregelen tenemen.
Immuniteit EN50082-1
WAARSCHUWING: Om te voldoen aan de emissie- en immuniteitsnormen dient dit apparaat te zijn voorzien van
afgeschermde kabels. Als het met niet-afgeschermde kabels wordt gebruikt, kan het zijn dat de gebruiker
maatregelen moet treffen om interferentieproblemen voor eigen rekening op te lossen.
Electrische Veiligheid EN60950, UL1950, CSA 950
Laser EN60825
Waarshuwing Klasse-1 laser produkt.
Waarchuwing Neit in de straal staren.
VEILIGHEID
GEVAAR VOOR BLIKSEMINSLAG
GEVAAR: NIET aan toestellen of KABELS WERKEN bij BLIKSEM.
VENTILATIEGATEN NIET BLOKKEREN
Stroom mag alleen via de adapternaar het apparaat toegevoerd worden.
EUROPE - EU
Gebruik een door TÜV gekeurde wisselstroomadapter van 12 Volt gelijkstroom, 500 milliampères.
BEDRIJFSTEMPERATUUR
De omgevingstemperatuur voor dit produkt magniet meer bedragen dan 40 graden Celsius.
ALLE LANDEN: het toestel installeren overeenkomstig de lokale en nationale elektrische voorschriften.
NORMES: ceproduit est conforme aux normes de suivantes :
Emission d'interférences radioélectriques EN55022 Classe A
MISE EN GARDE: dans un environnement domestique,ce produit peut provoquer des interférences
radioélectriques.Auquel cas,l'utilisateur devraprendre les mesures adéquates.
Immunité EN50082 - 1
AVERTISSEMENT : Il faut utiliser des câbles blindés pour ce produit afin de respecter les normes d’émission et
d’immunité.Sil’utilisateurchoisitd’utiliserdescâblesnonblindés,ilserapeut-êtrecontraintdeprendrelesmesures
nécessaires pour corriger les problèmes d’interférences, ainsi que d’assumer le coût correspondant.
Sécurité électrique EN60950, UL1950, CSA 950
Laser EN60825
Attention Producit laser di classe 1.
Attention Ne pas fixer le faisceau des yeux.
SÉCURITÉ
DANGER DE FOUDRE
DANGER: NE PAS MANIER le matériel ou les CÂBLES lors d'activité orageuse.
NE PAS BLOQUER LES FENTES D'AÉRATION
L'alimentation du concentrateur doit être uniquement fournie par l'adaptateur.
EUROPE - EU
Utiliser unadaptateur secteur conforme TÜV de12 V, 500 mA en courant continu.
TEMPÉRATURE DE FONCTIONNEMENT
Ce matériel est capable de tolérer une température ambiante maximum de 40 degrés Celsius.
POUR TOUS PAYS: Installer le matériel conformément aux normes électriques nationales etlocales.

Electrical Safety and Installation Requirements
vi
STANDARDIT: Tämä tuote onseuraavien standardien mukainen.
Radioaaltojen häirintä EN55022 Luokka A
VAROITUS: Kotiolosuhteissa tämä laite voi aiheuttaa radioaaltojen häiröitä, missä tapauksessa laitteen käyttäjän
on mahdollisestiryhdyttävä tarpeellisiin toimenpiteisiin.
Kestävyys EN50082-1
VAROITUS: Tämä tuote vaatii suojattuja kaapeleita toimiakseen emissio-ja häiriönsietostandardien mukaisesti.
Jostuotetta käytetäänilmansuojattujakaapeleita,käyttäjävoi joutuakorjaamaan häirinnänaiheuttamanongelman
omalla kustannuksellaan.
Sähköturvallisuus EN60950, UL1950, CSA 950
Laser EN60825
Varoitus Luokan 1 Lasertuote.
Variotus Älä katso säteeseen.
TURVALLISUUS
SALAMANISKUVAARA
ENGENVAARA: ÄLÄ TYÖSKENTELE laitteiden tai KAAPELEIDEN KANSSA SALAMOINNIN AIKANA.
ÄLÄ TUKI ILMAREIKIÄ
Tähtipisteeseen (hub) syötettävänvirran pitää tulla ainoastaan sovittimesta.
EUROPE - EU
Käytä TÜV-lisenssillä valmistettua verkkosovitinta, jonka tasajännitteen nimellisarvot ovat DC 12 V, 500 mA
(milliampeeria).
KÄYTTÖLÄMPÖTILA
Tämä tuote on suunniteltu ympäröivänilman maksimilämpötilalle 40° C.
KAIKKI MAAT: Asenna tuote paikallisten ja kansallisten sähköturvallisuusmääräysten mukaisesti.
STANDARD: Questo prodotto è conforme ai seguenti standard.
Emissione RFI (interferenza di radiofrequenza) EN55022 Classe A
AVVERTENZA: in ambiente domestico questo prodotto potrebbe causare radio interferenza. In questo caso
potrebbe richiedersi all'utente di prendere gli adeguati provvedimenti.
Immunità EN50082-1
AVVERTENZA: questo prodotto, seutilizzato con cavi schermati, èconforme alle norme sulle emissioni e
sull’immunità.In caso di uso senza cavi schermati, l’utente può dover adottare a proprie spese misure correttive
contro le interferenze.
Sicurezza elettrica EN60950, UL1950, CSA 950
Laser EN60825
Avvertenza Prodotto laser di Classe 1.
Avertenza Non fissare il raggio con gli occhi.
NORME DI SICUREZZA
PERICOLO DI FULMINI
PERICOLO: NON LAVORARE sul dispositivo o sui CAVI durante PRECIPITAZIONI TEMPORALESCHE.
NON OSTRUIRE LE PRESE D'ARIA
Questo dispositivo deve essere alimentato solo mediante l’adattatore.
EUROPE - EU
Utilizzare l’adattatore per c.a. da 12 V c.c. e 500 mA conforme alla normativa TÜV.
TEMPERATURA DI FUNZIONAMENTO
Questo prodotto è concepito per unatemperatura ambientale massima di 40 gradi centigradi.
TUTTI I PAESI: installare ilprodotto in conformità delle vigenti normative elettriche nazionali.

AT-FS201, AT-FS202 and AT-FS203 Installation Guide
vii
SIKKERHETSNORMER: Detteproduktet tilfredsstiller følgende sikkerhetsnormer.
RFI stråling EN55022 Klasse A
ADVARSEL:Hvisdetteproduktetbenyttestilprivatbruk,kanproduktetforårsakeradioforstyrrelse.Hvisdetteskjer,
må brukeren ta de nødvendige forholdsregler.
Immunitet EN50082-1
ADVARSEL: Detteproduktetmå brukes medvernede kablerfor å tilfredsstille emisjons-og fritakelsesstandarder.
Dersom produktet brukes meduvernede kabler, må brukeren muligens rette forstyrrelsesproblemene for egen
regning.
Elektrisk sikkerhet EN60950, UL1950, CSA 950
Laser EN60825
ADVARSEL Laserprodukt av klasse 1.
ADVARSAL Stirr ikke på strålen.
SIKKERHET
FARE FOR LYNNEDSLAG
FARE: ARBEID IKKE på utstyr eller KABLERi TORDENVÆR.
BLOKKER IKKE LUFTVENTILENE
All strømtilførsel må komme fra adapteren.
EUROPE - EU
Benytt TÜV-godkjent AC-adapter på 12V DC, 500mA (millismpere)
DRIFTSTEMPERATUR
Dette produktet er konstruert for bruk i maksimum romtemperatur på 40 grader celsius.
ALLE LAND: Produktet må installeres i samsvar med de lokale og nasjonale elektriske koder.
PADRÕES: Este produto atende aos seguintes padrões.
Emissão De Interferência De Radiofrequência EN55022 Classe A
AVISO: Num ambiente doméstico este produto pode causar interferência na radiorrecepção e, neste caso, pode
sernecessário que o utentetome as medidas adequadas.
Imunidade EN50082-1
ADVERTÊNCIA: Esteproduto requer a utilização de cabos blindados paracumprimento dos standardsde limites
de emissão e imunidade. Se o produto for utilizado com cabosnão blindados, o utilizador poderá necessitar de
tomar medidas para correcção de problemas de interferência, por sua própria conta.
Segurança Eléctrica TUV-EN60950, UL1950, CSA 950
Laser EN60825
Aviso Produto laser de classe 1.
Aviso Não olhe fixamente para o raio.
SEGURANÇA
PERIGO DE CHOQUE CAUSADO POR RAIO
PERIGO: NÃO TRABALHE no equipamento ounos CABOS durante períodos suscetíveis a QUEDAS DE RAIO.
NÃO BLOQUEIE AS ABERTURAS DE VENTILAÇÃO
Use somente o adaptador fornecido para alimentação elétrica do hub.
EUROPE - EU
UseumadaptadordecorrentealternadacomsaídaDCde12Ve 500mAemconformidadecomasespecificações
da TÜV.
TEMPERATURA DE FUNCIONAMENTO
Este produto foi projetado para uma temperatura ambientemáxima de 40graus centígrados.
TODOS OS PAÍSES: Instale o produto de acordo com as normasnacionaise locais parainstalações elétricas.

Electrical Safety and Installation Requirements
viii
ESTÁNDARES: Este producto cumple con los siguientes estándares.
Emisión RFI EN55022 Clase A
ADVERTENCIA: en unentornodoméstico,esteproductopuedecausarradiointerferencias,en cuyocaso,puede
requerirse del usuario que tome las medidas que sean convenientes al respecto.
Inmunidad EN50082-1
ADVERTENCIA: Este producto exige cables protectorespara ajustarse a lasnormasde emisióne inmunidad.Si
se utiliza con cablessin protección, el usuario tendrá que correr con los gastos por las medidas a tomar en caso
de problemas de interferencias.
Seguridad eléctrica TUV-EN60950, UL1950, CSA 950
Laser EN60825
¡ADVERTENCIA! Producto láser Clase 1.
¡ADVERTENCIA! No mirat fijamente el haz.
SEGURIDAD
PELIGRO DE RAYOS
ELIGRO: NO REALICE NINGUN TIPO DE TRABAJO O CONEXION en los equipos o en LOS CABLES durante
TORMENTAS ELECTRICAS.
NO BLOQUEE LAS ABERTURAS PARA VENTILACION
La energíapara el dispositivo central o"hub" debe provenir únicamente del adaptador.
EUROPE - EU
Utilizarun adaptador de corriente alternaautorizado TÜV de 12 voltiosde corriente continua y 500 miliamperios.
TEMPERATURA REQUERIDA PARA LAOPERACIÓN
Este producto está diseñadopara una temperatura ambiental máxima de 40 grados C.
PARA TODOS LOS PAÍSES: Monte el producto de acuerdo con los Códigos Eléctricos locales y nacionales.
STANDARDER: Denna produkt uppfyller följande standarder.
Radiostörning EN55022 Klass A
VARNING:Denna produktkangeupphovtillradiostörningarihemmet,vilketkantvingaanvändarentillattvidtaga
erforderliga åtgärder.
Immunitet EN50082-1
VARNING!Dennaproduktkräverskärmadekablarförattuppfyllastandardkravenföremissionochimmunitet.Om
den används med oskärmade kablar kan användaren vara tvungen att vidta åtgärder på egen bekostnad för att
åtgärda störningsproblemet.
Elsäkerhet TUV-EN60950, UL1950, CSA 950
Laser EN60825
VARNING! Laserproduktav klass 1.
VARNING! Laserstrålning när enheten är öppen.
SÄKERHET
FARA FÖR BLIXTNEDSLAG
FARA: ARBETA EJ på utrustningen eller kablarna vid ÅSKVÄDER.
BLOCKERA INTE LUFTVENTILERNA
Endast anslutningsenheten får varakraftkälla till centralen.
EUROPE - EU
Använd en växelströmsanslutningsenhet licensierad av TÜV. Likström 12V, 500mA.
DRIFTSTEMPERATUR
Denna produkt är konstruerad för rumstemperatur ej överstigande 40 grader Celsius.
ALLA LÄNDER: Installera produkten i enlighet med lokala och statliga bestämmelser för elektrisk utrustning.

ix
Table of Contents
Electrical Safety and Installation Requirements ..................................iii
Chapter 1
Description ......................................................................................................1
Key Features.......................................................................................................3
Switch Performance ....................................................................................4
Connectors ...................................................................................................4
LEDs ............................................................................................................5
External AC-DC Power Adapter.................................................................5
MDI/MDI-X Switch .....................................................................................6
Configuration Switches...............................................................................6
Functional Description.......................................................................................8
Frame Processing........................................................................................8
Address Recognition and Filtering.............................................................8
Chapter 2
Installation ......................................................................................................9
Package Contents...............................................................................................9
Speed and Duplex Mode Pre-installation Requirements..........................9
Maximum Packet Size Pre-installation Requirements...........................10
Installing the Switch as a Standalone.............................................................10
Setting the Configuration Switches for Speed and Duplex Mode ..........11
Configuring a 10/100Base-TX Port...........................................................12
Rack-mount Chassis Installation.............................................................14
Troubleshooting Techniques............................................................................15
Is the unit receiving power?......................................................................15
Connectivity Testing.................................................................................15
Is the LINK LED lit?.................................................................................16
Configurations ..................................................................................................17

x
Appendix A
Fast Switch System and Cable Specifications ......................................19
Pinout Assignments..........................................................................................21
Recommended Cables and Cable Specifications......................................22
Technical Support and Service.................................................................23
Warranty....................................................................................................23
Appendix B
Technical Support Fax Order ...................................................................25
Appendix C
AT-FS201, AT-FS202 and AT-FS203 Installation Guide Feedback ....27
Appendix D
Where To Find Us .........................................................................................29

1
Chapter 1
Description
The AT-FS201, AT-FS202, and AT-FS203 are self-learning, unmanaged dual-
port Fast Ethernet switches with RJ45, ST, and SC connectors for
10/100Base-TX, and 100Base-FX LAN segments. The switches are based on
store-and-forward switching architecture, providing error-free packet transfer.
They complement existing Allied Telesyn Fast Ethernet products and are fully
compliant with IEEE 802.3 and IEEE 802.3u standards.
The new form-factor and power receptacle make these switches compatible
with Allied Telesyn’s 10/100Base media converters. Allied Telesyn media
converters and the AT-FS200 family of switches can be installed into the
AT-MCR12 rack-mount chassis, providing convenient and flexible installation
for specific yet changing LAN requirements.
In addition, with a full-duplex link to any device, the switches provide twice
the bandwidth to transmit and receive simultaneously.
Figure 1 AT-FS203 Switch Front Panel and Other Model Connector Types
10Base-T/
100Base-TX
AUTO NEG
10Base-T/
100Base-TX
MDI MDI-X
FS203 FAST ETHERNET SWITCH IEEE 802.3/802.3U
AUTO NEG
TX
RX
COL
LNK
PWR
100
FD
MDI MDI-X
TX
RX
COL
LNK
100
FD
PORT 2PORT 1
TX RX TX RX
MDI MDI-X
AT-FS201 (ST) AT-FS202 (SC) AT-FS203(RJ45)

Description
2
Figure 2 and Figure 3 show the AT-FS201/AT-FS202 and AT-FS203 rear panel
respectively.
Figure 2 AT-FS201 and AT-FS202 Rear Panel and DIP Switch
Figure 3 AT-FS203 Rear Panel and DIP Switch
12VDC
21 345
1222
PORT
10
100 HALF FULL OFF ON
DUPLEX
MODE AUTO NEG
SPEED
(Mbps)
1522
1518
BYTES
21 345
1222
PORT
10
100 HALF FULL OFF ON
DUPLEX
MODE AUTO NEG
SPEED
(Mbps)
1522
1518
BYTES
12VDC
21 1212
PORT
10
100 HALF FULL OFF ON
DUPLEX
MODE AUTO NEG
SPEED
(Mbps)
1522
1518
BYTES
321 4567
21 1212
PORT
10
100 HALF FULL OFF ON
DUPLEX
MODE AUTO NEG
SPEED
(Mbps)
1522
1518
BYTES
321 4567

AT-FS201, AT-FS202 and AT-FS203 Installation Guide
3
Key Features
The switches have the following key features:
❑One 10/100Base-TX port and one 100Base-FX port ST connector for
AT-FS201; SC connector for AT-FS202)
❑Two 10/100Base-TX ports (RJ45 connectors) for Ethernet and Fast
Ethernet connectivity (AT-FS203)
❑LEDs for unit power, link, 10/100 speed, duplex mode,
auto-negotiation per port (no auto-negotiation on 100Base-FX port),
transmit data activity, receive data activity, and collision
❑All 10/100Base-TX ports are equipped with an MDI/MDI-X switch to
allow that port to connect to a workstation, repeater, hub, router,
bridge or another switch
❑External AC-DC Power Adapters are available for North America,
Continental Europe, and United Kingdom
❑Desk-mountable and rack-mountable (fits into the AT-MCR12
rack-mount chassis)
❑All 10/100Base-TX ports have DIP switches associated with them that
allow full range of port configurations, including auto-negotiate only
or user-selectable combinations of 10 or 100 Mbps and full- or half-
duplex.
❑All 10/100Base-FX ports have DIP switches associated with them that
allow user-selectable full- or half-duplex
❑Performs data packet forwarding and filtering at full wire speed (10
Mbps to 100 Mbps, 100 Mbps to 100 Mbps, and 10 Mbps to 10 Mbps)
❑Transparent to higher protocols
❑Isolates collision domains

Description
4
Switch Performance
The switches perform at:
❑148,800 pps for 100 Mbps and 14,880 pps for 10 Mbps for full wire
speed forwarding and filtering
❑200 Mbps maximum throughput in 100 Mbps, full-duplex mode
❑20 Mbps maximum throughput in 10 Mbps, full-duplex mode
❑Up to 8,192 unicast MAC addresses and unlimited multicast/
broadcast addresses
❑280 K bytes (per port) packet buffer
❑Low latency 14.3 µs (64-byte packet, 100 Mbps full-duplex)
Note
For definitions of technical terms associated with Allied Telesyn’s
products, refer to the Glossary on Allied Telesyn’s website at
www.alliedtelesyn.com.
Connectors
The AT-FS201 and AT-FS202 have one RJ45 10/100Base-TX connector and
one 100Base-FX connector (ST/SC), respectively. The AT-FS203 has two RJ45
10/100Base-TX connectors. See Figure 1.

AT-FS201, AT-FS202 and AT-FS203 Installation Guide
5
LEDs
The PWR LED in the upper right corner of the front panel shows that the
switch is getting power. Status LEDs are located on the front panel next to
each port. Table 1 lists and defines the LEDs.
External AC-DC Power Adapter
The power adapter supplies 12V DC to the switch. Allied Telesyn supplies an
approved safety compliant AC power adapter for the 120 and 240V AC
versions with an unregulated output of 12V DC.
Figure 4 External AC-DC Power Adapter (North American version shown)
Table 1 LEDs
LED State Color Description
PWR ON Green Power is applied.
LNK ON Green Link established on the port.
100 ON
OFF Green The port is operating at 100 Mbps.
The port is operating at 10 Mbps.
FD ON
OFF
Amber Full-duplex mode is enabled (two-way independent
transmission).
Half-duplex mode is enabled and indicates transmission
only in one direction at a time. Both devices contend for
the right to send data when active transmission is not
occurring.
AUTO NEG ON Green Auto-negotiation is enabled on this port.
TX ON Green Data is being transmitted on the port.
RX ON Green Data is being received on the port.
COL ON Amber The port is sensing a collision signal.

Description
6
MDI/MDI-X Switch
The MDI/MDI-X (Media DependentInterface/Media Dependent Interface with
Crossover) switch, located on the front panel, is a straight-through or
crossover cable selection switch. It enables the RJ45 port to be connected to a
repeater or DTE device without using a special crossover cable. The default
setting of the switch is MDI-X, which means you can connect the RJ45 port to
a workstation or to any other DTE device that uses a straight-through cable.
For the MDI configuration, slide the switch to the MDI position and connect
the RJ45 port to a repeater, hub, or switch using a straight-through cable. See
Figure 5.
Figure 5 MDI/MDI-X Switch
Configuration Switches
The configuration (DIP) switches are located on the rear panel of the
AT-FS200s. These switches control the operating modes of the ports and the
maximum packet size. See Figure 6 and Figure 7.
The 100Base-FX port must be set to either full- or half- duplex mode
(AT-FS201 or AT-FS202).
Each 10/100Base-TX port can be set independently to either auto-negotiate
only (ON) or can be user-selectable (OFF). When set to user-configurable mode
(OFF), the user can select the speed, either 10 Mbps or 100 Mbps and the
duplex mode.
The Byte DIP switch allows the user to select upper packet-size error limit,
1518 bytes (normal network packets) or 1522 bytes which allows the
AT-FS200 family of switches to be a passive component of the networks using
IEEE 802.1Q VLAN tagging. For detailed information on how to set the
configuration switches, see Table 2 and Table 3 and Figure 8 and Figure 9 in
Chapter 2, Installation.
10Base T/
100Base-TX 10Base-T/
100Base-TX
MDI MDI-X MDI MDI-X
PORT 2PORT 1
10Base-T/
100Base-TX
AUTO NEG
10Base-T/
100Base-TX
MDI MDI-X
FS203 FAST ETHERNET SWITCH IEEE 802.3/802.3U
AUTO NEG
TX
RX
COL
LNK
PWR
100
FD
MDI MDI-X
TX
RX
COL
LNK
100
FD
PORT 2PORT 1

AT-FS201, AT-FS202 and AT-FS203 Installation Guide
7
Figure 6 AT-FS201 and AT-FS202 DIP Switch
Figure 7 AT-FS203 DIP Switch
12VDC
21 345
1222
PORT
10
100 HALF FULL OFF ON
DUPLEX
MODE AUTO NEG
SPEED
(Mbps)
1522
1518
BYTES
21 345
1222
PORT
10
100 HALF FULL OFF ON
DUPLEX
MODE AUTO NEG
SPEED
(Mbps)
1522
1518
BYTES
12VDC
21 1212
PORT
10
100 HALF FULL OFF ON
DUPLEX
MODE AUTO NEG
SPEED
(Mbps)
1522
1518
BYTES
321 4567
21 1212
PORT
10
100 HALF FULL OFF ON
DUPLEX
MODE AUTO NEG
SPEED
(Mbps)
1522
1518
BYTES
321 4567

Description
8
Functional Description
The AT-FS200 family of switches function as unmanaged dual-port switches or
switches with automatic MAC Address Aging.
Frame Processing
The switches support store and forward switching at Fast Ethernet full-wire
speed either in 10 or 100 Mbps, half- or full-duplex mode. Packets entering
each port are stored in buffers. After the full packet is received, it is forwarded
or discarded appropriately depending on its destination address and error
status. This ensures that only error-free data packets destined to another
segment will be transferred across the switch, reducing network load. For
example, if the packet entering from Port 1 is destined to an end station on
Port 2, it will be forwarded if the Frame Check Sequence (FCS) is valid. If the
packet from Port 1 is destined to an end station also attached to Port 1, then
the packet is discarded.
The switch will discard CRC error, misaligned, runt, and under-sized/over-
sized packets. When the packet has dribble bits at the end, the switch will
truncate to octet boundary and check for a good FCS before forwarding.
Address Recognition and Filtering
Up to 8,192 MAC addresses can be stored in the MAC address table. The
switch will learn all new addresses in real-time after power-up with its
address self-learning mechanism. If the source address of an incoming packet
is not found in the Address Table, the switch waits until the end of the packet
to check for good CRC and then updates its MAC Address table. Because the
switch has Automatic Address Aging, if a source address entry in the table is
not updated within five minutes, that entry is deleted from the table. The
switch forwards multicast, broadcast, and unicast packets when the MAC
address table size is exceeded.

9
Chapter 2
Installation
Package Contents
Make sure the switch package contains the following items:
❑AT-FS201, AT-FS202, or AT-FS203 Fast Ethernet Switch
❑Four Protective Feet (for standalone use only)
❑External AC-DC Power Adapter (NorthAmerica, Continental Europe,
or United Kingdom)
❑This Installation Guide
❑Warranty Card
Contact your sales representative if any items are missing or damaged.
Speed and Duplex Mode Pre-installation Requirements
Do the following when configuring your switch.
❑The switch and its link partner must be set to operate at the same
speed and duplex mode. Incorrectly forcing a specific speed or duplex
mode can result in poor performance or no performance at all.
❑Only configure a port on the switch to full-duplex when connecting to
another switch or when connecting point-to-point to a single
workstation
❑Whenconnectingtheswitchto ahubor repeater,youmustsettheport
to half-duplex at the appropriate port speed for the attached device.

Installation
10
Maximum Packet Size Pre-installation Requirements
❑The factory default setting 1518 bytes is the IEEE 802.3 packet size
upper limit. Any packet exceeding this limit is considered illegal and,
as a result, the switch will drop that illegally-sized packet as part of
its error-handling operation.
❑Setting the Bytes DIP switch to 1522, makes the switch a passive
component of the networks, using the IEEE 802.1Q VLAN tagging.
❑Changing to 1522 bytes allows the switch to pass network packets
using IEEE 802.1Q VLAN tagging. This setting should be used only in
a network that is using IEEE 802.1Q VLAN tagging.
Installing the Switch as a Standalone
The following steps are for a standalone installation. For information
concerning the rack-mount chassis, see “Rack-mount Chassis Installation” on
page 14.
1. Remove all equipment from the package and store the packaging in a safe
place.
2. Attach the four rubber feet to the base of the unit, placing one rubber foot
in each corner. For rack-mount chassis installation, do not attach the four
feet.
3. Plug the AC-DC power adapter into an appropriate AC power outlet and
insert the power plug into the DC receptacle, located on the rear panel.
4. Verify that the PWR LED lights green.