Accton Technology FAST ETHERHUB-12S User Manual

Fast EtherHub-12s

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Installation Manual

Fast EtherHub-12s

Smart

Fast Ethernet Hub

with 12 100BASE-TX Ports

Copyright (c) 1997 by Accton Technology Corporation. All rights reserved.

No part of this document may be copied or reproduced in any form or by any means without the
prior written consent of Accton Technology Corporation.

Accton makes no warranties with respect to this documentation and disclaims any implied
warranties of merchantability, quality, or fitness for any particular purpose. The information in this
document is subject to change without notice. Accton reserves the right to make revisions to this
publication without obligation to notify any person or entity of any such changes.

Before operating this product, please review the statements on electomagnetic emission
interference and safety compliance in Appendix D.

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No. 1 Creation Road III,
Science-based Industrial Park
Hsinchu 300, Taiwan, R.O.C.
Phone: [phone]
FAX: [phone]
BBS: 886-3-5770-654
Internet: [e-mail]

Accton, EtherHub and SmartWatch are trademarks or registered trademarks of Accton Technology
Corporation. Other trademarks or brand names mentioned herein are trademarks or registered
trademarks of their respective companies.

EH3012-TX
150114-101
E0197-R02

86$+HDGTXDUWHUV

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San Jose, CA 95112
Phone: [phone]
FAX: [phone]
BBS: 408-452-8828
FAST FAX: [phone]

Package Contents

Carefully unpack the contents of the package and verify them against the
checklist given below.

Package Checklist

æ Fast EtherHub-12s (Model No. EH3012-TX)
æ AC power cord (optional)
æ Four rubber foot pads
æ Installation manual
æ Warranty registration card

Please inform your dealer immediately should there be any wrong, missing, or
damaged parts.

If possible, retain the carton, including the original packing materials. Use
them again to repack the unit in case there is a need to return it for repair.

To qualify for product updates and product warranty registration, fill in the

Owner Registration Card and return it to Accton Technology Corporation.

Package Contents i

Quick Installation

The Fast EtherHub-12s is a Class II repeater. It contains 12 100BASE-TX Fast
Ethernet ports. The smart design built into the front display panel provides a
friendly interface that simplifies installation and network troubleshooting. If
you are already familiar with basic network operations, you should be able to
install this hub as described below:

1. Unpack the Fast EtherHub-12s.

2. Find a location close to the network devices you need to connect, and within

easy reach of an electrical outlet.

3. Mount the hub on a desktop or any other flat surface. If you are installing

multiple hubs, you can stack them on top of each other (after attaching the
foot pads), or install them in an standard EIA 19-inch rack.

4. Connect any devices that use a standard network interface to the RJ-45

(MDI-X) station ports (e.g., a workstation, server or router). Use 100
Category 5 STP or UTP cable to connect to the hub, and be sure the length
of any twisted-pair connection does not exceed 100 meters. Refer to Chapter
3 for sample configurations.

To cascade to another hub or switch, run straight-through twisted-pair cable

from the (12MDI) daisy-chain port on this hub to any (MDI-X) station port
on the other device (or vice versa). Refer to Figure 3.2. If necessary, you
can also cascade between two station ports using crossover cable. However,
be sure not to exceed the maximum length between end nodes. Assuming
that the maximum cable length is used for end-node connections (i.e., 100
meters), then the inter-hub cabling should be limited to 5 meters. However,
if you need to extend this length of inter-hub cabling beyond 5 meters, then

W

Quick Installation iii

Fast EtherHub-12s User’s Guide

first calculate the maximum length permitted between each pair of end nodes
as described in Chapter 2 under the section on

Precise Cable Length Budgeting.

5. Verify network communications by ensuring that -

• you have made all the necessary connections

• you can access any connected resources

• the hub’s indicators are functioning properly

If you encounter any problems in installing the Fast EtherHub, refer to Chapter 2
for a detailed description of installation procedures, Chapter 3 for sample
configurations, or Appendix A for help in troubleshooting.

Note: Refer to Chapter 2 for a more detailed description of calculating the maximum cable
length permitted between two end nodes for Fast Ethernet.

iv Quick Installation

About this Guide

This guide is designed for the experienced network installer. It describes how

to install and operate Accton’s Fast EtherHub-12s. After reading this manual,
you should be able to use the front display panel and configure options to
manage all your network connections.

This manual covers the following topics:
Chapter 1 -

Brief description of Fast Ethernet, followed by a description of this hub and a
summary of its important features and specifications.

Chapter 2 ­Installing a Fast EtherHub and making basic network connections.

Chapter 3 ­Shows sample network configurations for a local area network.

Chapter 4 ­Detailed description of indicator panel and ports.

Appendices ­Troubleshooting, cable assignments, and product specifications.

Product Overview

Installing the System

Configuring the Network

Hardware Reference

About this Guide v

Contents

Chapter 1: Product Overview................................................. 1-1

Introduction to Fast Ethernet.....................................................................................1-1

Accton’s Fast EtherHub-12s......................................................................................1-1

Basic Features ...........................................................................................................1-2

Chapter 2: Installing the System............................................ 2-1

Pre-Installation Requirements ...................................................................................2-1

Connecting the Hub System......................................................................................2-2

Making a Connection via an MDI-X Station Port ................................................2-2

Making a Connection via the MDI Daisy-Chain Port...........................................2-3

Simplified Cable Length Constraints..............................................................2-4

Precise Cable Length Budgeting.....................................................................2-4

Providing Power to the EtherHub..............................................................................2-5

Verifying Port Status.................................................................................................2-6

Verifying System Operation......................................................................................2-6

Chapter 3: Configuring the Network......................................3-1

Stand-Alone...............................................................................................................3-1

Connecting Multiple Hubs ........................................................................................3-1

Using the RJ-45 Daisy-Chain Port........................................................................3-2

Precies Guidelines for Configuring Multiple Hubs ..............................................3-3

Chapter 4: Hardware Reference.............................................4-1

Front Panel ...............................................................................................................4-1

Indicators..............................................................................................................4-1

Fan Alert.........................................................................................................4-2

Power Status ...................................................................................................4-2

Statistical Display for System Performance....................................................4-3

Port Status Display..........................................................................................4-4

RJ-45 Ethernet Ports.............................................................................................4-5

Rear Panel ...............................................................................................................4-6

Power Socket........................................................................................................4-6

Contents vii

Fast EtherHub-12s User’s Guide

Appendix A: Troubleshooting................................................A-1

Diagnosing Hub Indicators........................................................................................A-1

System Diagnostics ...................................................................................................A-2

Power and Cooling Problems ...............................................................................A-2

Installation............................................................................................................A-2

Physical Configuration.........................................................................................A-3

Hub Integrity ........................................................................................................A-3

Ap p e ndix B: P ort and C a ble A s s ignmen t s.............................B-1

RJ-45 Port ...............................................................................................................B-1

Appendix C: Specifications....................................................C-1

Product Specifications...............................................................................................C-1

Appendix D: Regulatory Standards Compliance.................. D-1

EMI Certification ......................................................................................................D-1

FCC Class B Certification....................................................................................D-1

Voluntary Control Council for Interference (VCCI-2).........................................D-2

European Community Immunity Requirements....................................................D-3

CE Mark Declaration of Conformance (for EMI and Safety)...............................D-3

Safety Compliance.....................................................................................................D-4

Underwriters Laboratories Inc..............................................................................D-4

Sicherheitshinweise..............................................................................................D-5

Appendix E: Product Support Services ................................E-1

Product Registration..................................................................................................E-1

Problem Report .........................................................................................................E-1

Hardware Repair Service...........................................................................................E-1

Bulletin Board Service (BBS) ...................................................................................E-2

Interactive Fast Fax (U.S.A. office) ..........................................................................E-2

Technical Support .....................................................................................................E-3

viii Contents

Fast EtherHub-12s User’s Guide

Limited Warranty.......................................................................................................E-4

Customer Remedies..............................................................................................E-4

Return Process......................................................................................................E-5

Accton Offices...........................................................................................................E-6

Ordering Information ................................................................................................E-6

Glossary
Index

List of Figures

Figure 3.1 Stand-Alone Configuration....................................................................3-1

Figure 3.2 Multiple Hub Configuration Using the Daisy-Chain Port......................3-2

Figure 3.3 Cabling Limits for Multiple Hub Configuration.....................................3-4

Figure 4.1 Front Panel.............................................................................................4-1

Figure 4.2 Indicators ...............................................................................................4-2

Figure 4.3 Rear Panel ..............................................................................................4-6

Figure B-1 RJ-45 Connector (on the Hub Side) .......................................................B-1

List of Tables

Table B-1 RJ-45 Pin Assignments............................................................................B-1

Contents ix

Chapter 1: Product Overview

Introduction to Fast Ethernet

Standard 10 Mbps Ethernet has served well for past generations of 286 and
386 machines performing simple file transfers. However, with the inevitable
growth in corporate network size and the introduction of fully-functional 32-bit
PC architectures, and operating systems running complex applications, 10 Mbps
Ethernet has become a serious bottleneck.

With the recent flood of choices for upgrading media bandwidth, 100 Mbps
Fast Ethernet has become the most popular choice because of its low cost,
compatibility with existing Ethernet applications, and the fact that it can run on
top of an installed base of twisted-pair cabling. Fast Ethernet can be easily
integrated into an existing 10 Mbps Ethernet environment with no need for
protocol translation or changes to network software.

Accton’s Fast EtherHub-12s

The Fast EtherHub-12s includes 12 100BASE-TX Ethernet ports. It provides a
friendly design that simplifies installation and network troubleshooting. The
SmartWatch
well as Partition, Link and Traffic LEDs to ease network management.

TM

indicator panel includes Utilization and Collision rate LEDs, as

The Fast EtherHub-12s can be used to relieve common network congestion,
regardless of whether it is caused by too many stations contending for limited
bandwidth or by a server that is supporting too many users. It can significantly
improve access both to key servers and to the network backbone. This hub not
only delivers a vast improvement in network response time, but helps you
maintain outstanding performance as your user community continues to grow.

Product Overview 1-1

Fast EtherHub-12s User’s Guide

Basic Features

• Transmits data at 100 Mbps for demanding applications

• Conforms to the IEEE 802.3u repeater specification for 100BASE-TX

• Provides 12 RJ-45 100BASE-TX station ports (using MDI-X wiring)

• Port 12 can serve as an MDI-X station port (for connection to network

devices such as workstations or servers) or as an MDI daisy-chain port (for

connection to network devices such as hubs or switches), eliminating the

need for crossover cables

• Supports 100Ω Category 5 shielded or unshielded cable (STP or UTP)

• Friendly design that monitors network utilization, collisions, link and port

partition status

• LED indicator panel including Utilization and Collision rate indicators for

reporting hub activity and facilitating problem diagnosis

• Automatically partitions bad ports to protect the network system

• Automatic polarity detection and correction permits automatic adjustment

for wiring errors

• Plug-and-play operation

• An Alert LED that shows if the fan has failed

The Fast EtherHub-12s also supports the following basic system safeguards:

• This hub features automatic partitioning and reconnection, jabber lockup

protection, and automatic polarity detection for network cabling.

1-2 Product Overview

Fast EtherHub-12s User’s Guide

• With automatic partitioning and reconnection, any port is automatically

isolated if excessive collisions occur on it. When the condition is corrected,

the port is automatically reconnected.

• With the jabber lock-up function, the hub automatically stops transmission

of abnormal Ethernet frames that may cause data loss for all network users.

(Jabber refers to abnormal Ethernet frames which are much too long and

may come from a malfunctioning Ethernet card.)

• With automatic polarity detection, the hub recognizes and adjusts for

attached cable assemblies which may be wired with incorrect polarity on the

receive pair.

Product Overview 1-3

Chapter 2: Installing the System

This chapter provides information on installing the Fast EtherHub-12s, estab­lishing network connections, and configuring the system. You may install this
hub on any level surface (e.g., a table or shelf) or in a standard EIA equipment
rack. However, please take note of the following minimum site requirements
before you begin.

Pre-Installation Requirements

Before you start actual hardware installation, make sure you can provide the
right operating environment, including power requirements, sufficient physical
space, and proximity to other network devices that are to be connected. Verify
the following installation requirements:

• Power requirements: 100 to 240 VAC (± 10%) at 50 to 60 Hz (± 3Hz). The

hub’s power supply automatically adjusts to the input voltage level.

• The EtherHub should be located in a cool dry place, with at least 10 cm. of

space at the front and back for ventilation.

• Place the hub out of direct sunlight, and away from heat sources or areas

with a high amount of electromagnetic interference.

• Check if network cables and connectors needed for installation are available.

• Find a suitable location at the center of the devices you want to link, and

near a power outlet

Installing the System 2-1

Fast EtherHub-12s User’s Guide

Connecting the Hub System

This hub is a Fast Ethernet repeater for 100BASE-TX networks. The
EtherHub-12s has 12 RJ-45 station ports, of which Port 12 can serve as either a

station port or a daisy-chain port (depending on the port’s switch setting ). The
station ports allow you to make connections to dev ices such as a work station,
server or router. You can also cascade to another compatible hub or switch by
connecting an MDI port on one device (e.g., port
MDI-X port on the other device. Or you can cascade from an MDI port on
another device to any MDI-X port on this hub. See Figure 4.1.

Making a Connection via an MDI-X Station Port

You can connect an RJ-45 station port on the hub to any device that uses a
standard network interface such as a workstation or server, or also to a network
interconnection device such as a router (depending on the port type
implemented).

1. Prepare the network devices you wish to network. Make sure you have

installed suitable 100BASE-TX network interface cards for making a

connection to any of the hub’s station ports. You also need to prepare

straight-through shielded or unshielded twisted-pair cables with RJ-45 plugs

at both ends. Use 100

2. Connect one end of the cable to the RJ-45 port of the network interface card

(or comparable port type) on the device you are attaching to the hub, and the

other end to any available (MDI-X) station port on the hub. When inserting

an RJ-45 plug, be sure the tab on the plug clicks into position to ensure that it

is properly seated. Using the hub in a stand-alone configuration, you can

network up to 12 nodes.

I

Notes:

Do not plug a phone jack connector into the RJ-45 port. This may damage the hub.
Use only twisted-pair cables with RJ-45 connectors that conform with FCC standards.

1. When connecting to station Port 12, set the port selection switch to M DI-X .

2. Make sure each twisted-pair cable does not exceed 100 meters.

W Categ o r y 5 cable f o r a l l connections.

12MDI on this hub) to an

2-2 Installing the System

Fast EtherHub-12s User’s Guide

Making a Connection via the MDI Daisy-Chain Port

1. To make a direct connection to another compatible repeater or switch, use the

12MDI daisy-chain port. When connecting to this port, remember to set the

port selection switch

MDI.

2. Prepare straight-through shielded or unshielded twisted-pair cables with

RJ-45 plugs at both ends. Use 100

W Category 5 cable for all connections.

Connect one end of the cable to Port 12MDI on this hub, and the other end to

a standard MDI-X station port on the other device. When inserting an RJ-45

plug, be sure the tab on the plug clicks into position to ensure that it is

properly seated.

Notes:

1. When connecting to Port 12MD I, set the port selection switch to M D I.

2. Make sure the length of twisted-pair cable does not exceed 100 meters.

3. To connect to another hub or switch, you may also run straight-through
twisted-pair cabling from a station port on this hub to a crossover port on
another device. However, if you must connect to another device via station
ports at both ends of the cable, use crossover cabling.

Distance Limit for Fast Ethernet Cabling

There are two common ways to calculate maximum cable length. The first

way, which is refered to as the “Simplified Cable Length Constraints” method
assumes that the maximum permissible cable length is used to connect various
end-node devices (such as workstations or servers) to the hub. A more careful
method of calculating maximum cable length, referred to as the “Precise Length
Budgeting” method, requires you to measure the exact cable length for each
pair of nodes that need to communicate, and to provide the signal delay time for
each hub in your system. Both of these methods are described in this section.

Installing the System 2-3

Fast EtherHub-12s User’s Guide

Simplified Cable Length Constraints

The Fast EtherHub-12s is a Class II repeater. IEEE recommends that Class II
hubs be limited to a cascade of two hubs. The simplest rule is that workstation
connections be limited to 100 meters for twisted-pair cabling, and that interhub
cabling be limited to 5 meters. If you are stacking hubs in a wiring closet, this
is good advise. When a hub is located in central wiring closet, connections to
end users tend to be very long. Using these assumptions, then maximum cable
lengths depend on the device type you want to attach to the hub, as shown in
the following table:

cable type workstation another hub switch

twisted-pair 100 meters 5 meters 100 meters

When connecting to another hub, traffic is confined to a single collision
domain. However, when connecting to a collapsed backbone (e.g., a switch or
router), the collision domain is broken up, enabling the use of longer cable
lengths as illustrated in the preceeding table.

Precise Cable Length Budgeting

If you plan on installing a network for a small office, it may not be convenient
to place hubs within 5 meters of each other, and then run up to 100 meters of
cabling for each end user. This kind of installation can be very messy and
wastes a lot of cabling. Depending on how your users are spread out, it may be
more convenient to run a longer length of inter-hub cabling (say 50 meters or
more), and then run shorter lengths of cable from each hub to the end users.
Depending on the inherent delay in the hub and the maximum cable lengths
required, it may even be possible to cascade up to three Fast Ethernet hubs.

However, when setting up these kinds of distributed cascades, you have to be
very careful in calculating the maximum length for each node pair. All end­node devices (e.g., workstations or servers) must be within 100 meters of the

2-4 Installing the System

Fast EtherHub-12s User’s Guide

connected hub when using twisted-pair cabling. However, when linking one or
more Fast Ethernet repeaters together (i.e., in the same collision domain), the
overall length of cable used between any two nodes should not exceed the
limits outlined in the IEEE 802.3u standard. In precise term s, the maximum
length of cabling that can be run from end-node to end-node is

≥ S(repeater equivalent length) + S(length of CAT-5 twisted-pair cable)

367m
This 100BASE-TX Class II device has an inherent repeater delay of 90 bit time

or 80 meters of twisted-pair cable. Taking a daisy chain of two hubs connected
via twisted-pair cabling for an example, the maximum length from node to node
is 367m - (2 x 80m) = 207m. Therefore, if both node A and B are linked to
separate repeaters in a two hub system, each using 100 m eters of cable to connect
to their respective hub, then the inter-hub cabling will be limited to 5 meters
(i.e., 207m - 2x100m = 7m, which is then reduced to 5 meters according to a
common wiring rule).

Providing Power to the EtherHub

1. Power on the hub by plugging the power cord into the power socket at the

rear of the EtherHub (see Figure 4-2), and the other end into a power outlet.

2. Check the LED marked

will automatically select the setting that matches the connected input voltage.
Therefore, no additional adjustments are necessary when connecting it to
any input voltage within the range marked on the rear panel.

The unit supports a “hot remove” feature which permits you to connect/

F

disconnect cables without powering off the hub and without disrupting the
operation of attached devices.

Power on the front panel to see if it is on. The unit

Installing the System 2-5

Fast EtherHub-12s User’s Guide

Verifying Port Status

Check each connection by viewing the port status indicators listed below. (For
a more detailed description of these indicators, refer to Chapter 4.)

Link Indicates that the port has established a valid network connection.
Traffic Indicates traffic traversing the port.
Partition Indicates that the port has been isolated from the hub due to

excessive errors.

If the Link status indicator is not functioning properly, or you experience any
other difficulties in setting up the hub, refer to Appendix A.

Verifying System Operation

Verify that all attached devices have a valid connection. The hub monitors
link status for each port. If any device is properly connected to the hub and
transmitting a link beat signal, the Link indicator lights up for the corresponding
port. If the Link indicator fails to light up when you connect a device to the
hub, check the following items:

• Be sure the twisted-pair cable is properly attached to the connected device

and the hub. Verify that the RJ-45 plug snaps into place when attached.

• See if the twisted-pair cable is functioning properly by using it for another

port and attached device that already displays valid indications when
connected to the network.

• Check the length of the twisted-pair connection to be sure it does not exceed

100 meters. If you are using bit budget calculations to determine maximum
cable lengths, then be sure you have not exceeded the maximum cable length
calculated for any potential node pair.

2-6 Installing the System

Fast EtherHub-12s User’s Guide

• Test the adapter for an attached workstation by trying it in another computer

that has been successfully connected to the network.

If you still can’t resolve the problem , please refer to

Troubleshooting in Appendix A.

Installing the System 2-7

Chapter 3: Configuring the Network

The Fast EtherHub-12s allows great flexibility in configuring your network.
You can use it in a stand-alone or multiple hub configuration. Some of the
common applications for this Fast EtherHub are described in this chapter.

Stand-Alone

This hub can be used in a simple stand-alone configuration as illustrated below.
In compliance with IEEE 802.3u standards, the maximum cable distance
between the hub and any workstation is 100 meters for twisted-pair cable.

Figure 3-1 Stand-Alone Configuration

Connecting Multiple Hubs

In a multiple hub configuration, the maximum overall segment length for inter­hub cabling depends on many factors, including the length of the cables used to
connect station nodes to the hub system and the number of hubs you cascade
together. You can use simple calculations to determine the maximum network
diameter or the stricter guidelines outlined by IEEE 802.3u standard.

Configuring the Network 3-1

Fast EtherHub-12s User’s Guide

Using the RJ-45 Daisy-Chain Port

You can easily connect to another hub via the MDI daisy-chain port (Port 12).
When using
hub cable length is 5 meters. Figure 3-2 shows a sample configuration.

Simplied Cable Length Constraints as described in Chapter 2, the inter-

Figure 3-2 Multiple Hub Configuration Using the Daisy-Chain Port

3-2 Configuring the Network

Fast EtherHub-12s User’s Guide

Precise Guidelines for Configuring Multiple Hubs

A detailed formula for calculating maximum cable length was provided in the
section on
maximum length of cabling that can be run from end-node to end-node is:

367m
For the daisy chain of three hubs shown in Figure 3-3, communications must

be supported for node pairs AB and AC. In this case, first determine the
limitations on cable length found on the longest path (i.e., the path with the
longest delay time).

Remember that this Class II device has an inherent repeater delay of 90 bit time
or 80 meters of twisted-pair cable. Therefore, if node A and B are linked to
repeaters 1 and 3 respectively (each using 50 meters of twisted-pair cable), then
the maximum length from node A to B is 367m - (3 x 80m) = 127m and the
total inter-hub cabling will be limited to 27 meters (i.e., 127m - 2x50m = 27m).
Therefore, if you use 15 meters of twisted-pair cable to connect hubs 1 and 2,
then 12 meters of cable can be used to connect hubs 2 and 3.

Then, if node A and C are linked to adjacent repeaters 1 and 2 in this system,
the maximum length of twisted-pair cable that can be used to connect node C to
hub 2 is 367m - 2*80m - 50m - 15m = 142 meters. However, the maximum
length for any twisted-pair connection cannot exceed 100 meters.

Precise Cable Length Budgeting in Chapter 2. This formula stated that the

≥ S(repeater equivalent length) + S(length of CAT-5 twisted-pair cable)

Configuring the Network 3-3

Fast EtherHub-12s User’s Guide

Figure 3-3 Cabling Limits for Multiple Hub Configuration

Notes:

1. The maximum length for each cable must be determined by calculations for the
longest path (i.e., node-to-node connection) that passes through that segment.

2. To control the number of hubs in a path, we recommend that one hub be used to
connect to several other hubs. Make sure there is only one path between any two
stations on the network.

3. If you need to connect network devices over a long distance, use a switching hub
or router to split the network up into two or more collision domains. For detailed
information on purchasing the required equipment, contact your local distributor or
Accton representative for support.

3-4 Configuring the Network

Chapter 4: Hardware Reference

Before connecting any network device to this hub, please review Chapter 2 for
information on system installation and Chapter 3 for a brief look at common
network architectures. This chapter describes the hardware features of the Fast
EtherHub-12s. For easier management and control of the hub, familiarize
yourself with the display indicators and ports.

Front Panel

There are 12 RJ-45 MDI-X station ports and 1 RJ-45 MDI daisy-chain port on
the front panel. Moreover, the system indicators provide a simple interface for
monitoring the hub. The front panel includes an alert indicator to show if the
fan has failed, a power indicator, a statistical display for network traffic, and
port status indicators as shown below.

100BASE-TX Class II Repeater

Figure 4.1 Front Panel

Indicators

The SmartWatch indicator panel simplifies monitoring of various network
conditions by providing LEDs that indicate the status of each station port and
the overall condition of the hub. It provides all the key information required to
manage your network on a daily basis. The following pages list the indicators
and their functions.

Hardware Reference 4-1

Fast EtherHub-12s User’s Guide

The front panel array provides indicators that show the utilization of network
bandwidth and indicate the status of por t c o n n e c ti o n s . It includ e s port status
indicators and a statistical display for network traffic as shown below.

Figure 4.2 Indicators

Fan Alert

Color: Red
Label:

Alert

Function: Fan status

Condition Indication

ON The unit’s fan has failed. (Call for service)
OFF The unit’s fan is functioning properly.

Power Status

Color: Green
Label:

Power

Function: Power indicator

Condition Indication

ON Unit is receiving power.
OFF Power is disconnected, no power received.

4-2 Hardware Reference

Fast EtherHub-12s User’s Guide

Statistical Display for System Performance

Utilization - (Utilization%) The statistical indicators show the percentage of valid data

passing through all ports compared to overall network bandwidth (updated every

0.5 seconds). There are 5 LEDs representing the percentage of network utilization.

The corresponding LEDs light up to show that the utilization of LAN bandwidth

has reached this level. When active, these LEDs behave like a stereo’s equalizer
display.

For example, if network utilization reaches 1%, the LED labeled 1% will light up.
However, if network utilization rises above 1% (e.g., 30%), the LED labeled 30
and all the other LEDs before it (i.e., 1, 5 and 15) will also light up in rapid
succession. These indicators monitor the share of valid network frames handled
by the hub within a 100 Mbps bandwidth. They provide a quick way to monitor
the current traffic load relative to the network’s capacity.

Collision - (Collision%)- The statistical indicators show the percentage of packet

collisions occurring out of the total packets transmitted by the hub. C ollisions
occur when two or more devices connected to a hub attempt to transm it data
simultaneously on the network. When a collision occurs, dev ices pause and then
re-transmit after a pseudo-random wait period. Because wait periods differ among
devices, successive collisions become increasingly improbable.

The Collision LEDs assist the network manager in monitoring the percentage of
packet collisions occurring relative to the total packets transmitted by the hub.
When collisions reach a level marked on the front panel display, the correspond­ing LED lights up. For example, if pack et collisions reach 1%, the LED labeled
1% will light up. However, if collisions go beyond 1% (e.g., 15%), the LED
labeled 15

+

% and all the other LEDs before it (i.e., 1, 3, 5 and 10) also light up

in rapid succession.

Hardware Reference 4-3

Fast EtherHub-12s User’s Guide

Note: If the hub displays a high collision rate, check to see if any of the connected
devices are malfunctioning or if a loop has been formed in your network connections.
Otherwise, you may need to reconfigure your network to balance the traffic load.

Port Status Display

Partition Status

Color: Red
Label:

Partition

Function: Shows i f th e p o r t h a s b e en i s o la t ed f r o m the network

Condition Indication

ON Indicates port has been partitioned due to an abnormal network condition.
OFF Port is in good condition.

A port is temporarily partitioned when a line error or too many collisions are
detected on the attached segment. While it is automatically partitioned, the
port continues to receive data from the segment. However, data is not
transmitted onto the segment. When the problem is corrected or a valid data
packet is received through the port, the port is automatically reconnected.

When partitioning occurs, the port’s corresponding Partition LED will be
continually lit (RED light). Otherwise, this LED should be OFF (unlit).

Notes:

Link Status

1. When a long run of collisions occur on the cable connected to a hub port
(i.e., 64 collisions), that port is automatically partitioned by the hub. It is
automatically reconnected when a collision-free data packet at least 512
bits long (i.e., a minimum size legal packet) passes through the port.

Color: Green
Label:

Link

Function: Indic a te s a valid network connection associated with the port.

Condition Indication

ON Indicates a valid link has been established on this port.
OFF No valid link has been established on this port.

4-4 Hardware Reference

Fast EtherHub-12s User’s Guide

Troubleshooting: If the Link LED does not light up when a device is connected to its corre-

sponding port, check that both the hub and connected device are powered on. Be sure
the cable length for all devices connected to the hub are within the limits described
under Distance Limit for Fast Ethernet Cabling in Chapter 2. As a general rule, be sure that
none of your twisted-pair cables exceed 100 meters. You should hav e standard, straight­through cables and not crossover or other specialized cables.

Incoming Traffic

Color: Green
Label:

Traffic

Function: Indicates traffic entering the port.

Condition Indication

BLINKING Indicates the port is receiving packets; blinking is

proportional to the traffic entering the port.

OFF No packets are being received by this port.

RJ-45 Ethernet Ports

This hub includes 12 Fast Ethernet station ports; of which Port 12 can also
serve as a daisy-chain port. Use straight-through twisted-pair cable to connect
the shielded MDI-X station ports to a workstation or server; or to connect the
MDI port to another network interconnection device, such as a hub or switch.
When using Port 12, remember to set the selection switch to MDI-X when
connecting to a workstation, or to MDI when cascading to another hub or
switch. Remember to use 100
(STP or UTP) for all standard connections.

Wcategory 5 straight-through twisted-pair cable

Note: If you must cascade between MDI-X station ports on two hubs, then use
crossover cable.

Hardware Reference 4-5

Fast EtherHub-12s User’s Guide

Rear Panel

The rear panel on the hub includes a full-range power socket.

Figure 4.3 Rear Panel

Power Socket

The power socket accepts AC power from 100 to 240V at 50 to 60Hz. The unit
is equipped with a universal full-range power source.

4-6 Hardware Reference

Appendix A: Troubleshooting

Diagnosing Hub Indicators

This Fast EtherHub can be easily monitored through its comprehensive panel
indicators. These indicators assist the network manager in identifying
problems the hub may encounter. This section describes common problems
you may encounter and possible solutions.

Symptom: Power indicator d o e s n o t l i g h t u p .
Cause: Defective power outlet, power cord, or internal power supply.
Solution: Have your unit’s power supply or Power LED replaced. Ask for

dealer assistance.

Symptom: Partition indicator lights up.
Cause: Hub has partitioned a port.
Solution: If port partitioning has occurred, the hub will automatically enable

the port when the faulty condition disappears.

Symptom: Link/Traffic i n d ic a t o r remains unlit afte r m a king a connection.
Cause: Workstation’s network adapter, the cable, or the hub port is defective.
Solution: Verify that the hub and attached device are powered on. Be sure the

cable is p l u gged in to b o t h th e hub a n d c o rr e s ponding device. Verify
that the proper cable type is used (Chapter 2), and that its length
does not exceed 100 meters. Check the adapter on the attached
device and cable connections for possible defects. Replace the
defective adapter or cable if necessary

Use the diagnostic procedures described in the following section to verify that
all other system components are functioning properly. If you still cannot
resolve the problem, contact your Accton distributor for assistance.

Troubleshooting A-1

Fast EtherHub-12s User’s Guide

System Diagnostics

Power and Cooling Problems

If the Power indicator does not turn on when the power cord is plugged in, you
may have a problem with the power outlet, power cord, or internal power
supply as explained in the previous section. However, if the unit powers off
after running for a while, check for loose power connections, power losses or
surges at the power outlet, and verify that the fan on back of the unit is
unobstructed and running prior to shutdown. If you still cannot isolate the
problem, then the internal power supply may be defective. In this case, contact
your Accton distributor for assistance.

Installation

Verify that all system components have been properly installed. If one or more
components appear to be malfunctioning (e.g., the power cord or network
cabling), test them in an alternate environment where you are sure that all the
other components are functioning properly.

Cabling

1. Verify that the cabling type is correct. Be sure all cable connectors are
securely seated in the required ports. Use 100
cable for all standard twisted-pair connections.

2. Make sure all devices are connected to the network. Equipment may have

been unintentionally disconnected from the network.

3. When cascading two devices using RJ-45 station ports at both ends of the
cable (i.e., not the MDI port), make sure a crossover cable is used. Crossover
cable should only be used if a daisy-chain port is not available.

W Category 5 straight-through

A-2 Troubleshooting

Fast EtherHub-12s User’s Guide

External Adapters

Make sure the network interface hardware and software drivers for the attached
devices are function properly. Check the adapter cards and associated drivers
used in any attached workstation or server.

Physical Configuration

If problems occur after altering the network configuration, restore the original
connections, then try to track the problem down by implementing the new
changes, one step at a time. Ensure that cable distances and other physical
aspects of the installation do not exceed recommendations.

Hub Integrity

As a last resort verify the hub’s integrity with a power-on reset. Turn the
power to the hub off and then on a few times. If the problem still persists and
you have completed all the preceding diagnoses, contact your Accton
distributor for further assistance. (Refer to Appendix E.)

Troubleshooting A-3

Appendix B:

Port and Cable Assignments

RJ-45 Port

Figure B-1 RJ-45 Connector (on the Hub Side)

Pin

1 Input Receive Data + Output Transmit Data +
2 Input Receive Data - Output Transmit Data ­3 Output Transmit Data + Input Receive Data +
6 Output Transmit Data - Input Receive Data -

4,5,7,8 Not Used Not Used

MDI-X Assignment

(Station Port 1 ~ 12)

Table B-1 RJ-45 Pin Assignments

MDI Assignment

(Cascade Port 12)

Schematics for both straight and crossover twisted-pair cable are shown below.

Straight-Through Crossover

(Hub) (Adapter) (Hub) (Hub)

1 IRD+ 1 OTD+ 1 IRD+ 1 IRD+
2 IRD- 2 OTD- 2 IRD-
3 OTD+ 3 IRD+ 3 OTD+ 3 OTD+
6 OTD- 6 IRD- 6 OTD- 6 OTD-

Cable and Port Assignments B-1

2 IRD-

Appendix C: Product Specifications

Transmission Technique Baseband
Topology Star or Tree
Access Method CSMA/CD, 100Mbps
Standards Conformance IEEE 802.3u 100BASE-TX Class II Repeater
Media Supported Unshielded or shielded twisted-pair cable

(100

W Category 5 STP/UTP)

Interfaces 12 RJ-45 MDI-X station ports, Port 12 can be switched to

function as an MDI-X station port or MDI daisy-chain port

Hub-to-Workstation Distance 100 meters maximum using category 5 STP or UTP cable
Daisy-Chain Distance (2 hubs) 5 meters (assuming 100 meters from each node to hub)
Dimensions 440 mm x 192 mm x 43 mm

(17.32"x 7.56" x 1.69")

Power Input 100 to 240 VAC (10%), 50 to 60 Hz ( 3%)
Power Consumption 2 Amp max. @ 100 VAC, 1 Amp @ 220 VAC
Temperature 0°C to 40°C (Standard Operating)
Humidity 5% to 95% (Noncondensing)
Certification CE Mark

Emissions FCC Class B, VCCI Class 2, CISPR 22 Class B
Immunity IEC 1000-4-2,3,4,6
Safety UL, CSA, TÜV/GS

Product Specifications C-1

Appendix D:

Regulatory Standards Compliance

EMI Certification

FCC Class B Certification

Accton Technology Corporation
Model Numbers: EH3012-TX
FCC ID: HED3012EHLCT-TX

This device complies with Part 15 of the FCC Rules. Operation is subject to the
following conditions:

1. This device may not cause harmful interference, and

2. This device must accept any interference received, including interference that

may cause undesired operation.

Warning!

device, pursuant to Part 15 of the 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 the
instructions, may cause harmful interference to radio communications. However, there is no
guarantee that interference will not occur in a particular installation. If this equipment does 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 receiver

• Connect the equipment into an outlet on a circuit different from the one which the receiver is

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

This equipment has been tested and found to comply with the limits for a Class B digital

connected to

You are cautioned that changes or modifications not expressly approved by the party
responsible for compliance could void your authority to operate the equipment.

Regulatory Standards Compliance D-1

Fast EtherHub-12s User’s Guide

Warnings

1. Wear an anti-static wrist strap or take other suitable measures to prevent
electrostatic discharge whenever handling this equipment.

2. When connecting this hub to a power outlet, connect the field ground lead
on the tri-pole power plug to a valid earth ground line to prevent electrical
hazards.

You may find the following booklet prepared by the Federal Communications
Commission helpful:

The Interference Handbook

This booklet is available from the U.S. Government Printing Office. Washington, D.C.

20402. Stock No. 004-000-00345-4.

Note: In order to maintain compliance with the limits of a Class B digital device, Accton
requires that you use a quality interface cable when connecting to this device. Changes

or modifications not expressly approved by Accton could void the user’s authority to
operate this equipment. Suggested cable type is:

• Twisted-pair for RJ-45 connections: 100WCategory 5 STP or UTP

Voluntary Control Council for Interference (VCCI-2)

This equipment is in the 2nd Class category and conforms to the standards set by the
Voluntary Control Council for Interference by Data Processing Equipment and
Electronic Office Machines aimed at preventing radio interference in residential areas.

2nd Class category equipment is qualified to be used in or near residential areas.
However, if this equipment is placed near a functioning radio or telephone, data errors
may result.

D-2 Regulatory Standards Compliance

Fast EtherHub-12s User’s Guide

Read the instructions for correct handling.

European Community Immunity Requirements

This unit was tested and found to comply with the Class B limits of EN55022 (CISPR

22) and the immunity requirements of EN50082-1.

CE Mark Declaration of Conformance (for EMI and Safety)

This is to certify that this product complies with ISO/IEC Guide 22 and EN45014.
It conforms to the following specifications:

EMC: EN55022(1988)/CISPR-22(1985) class B

IEC 1000-4-2(1995)/IEC 801-2(1991) 4kV CD, 8kV AD
IEC 1000-4-3(1995)/IEC 801-3(1984) 3V/m
IEC 1000-4-4(1995)/IEC 801-4(1988) 1kV - (power line), 0.5kV - (signal line)
IEC 1000-4-6(1995) 3Vrms

This product complies with the requirements of the Low Voltage Directive 73/23/EEC
and the EMC Directive 89/336/EEC.

Warning!

Do not plug a phone jack connector in the RJ-45 port. This may damage the hub.

Les raccordeurs ne sont pas utilisé pour le système téléphonique!

Regulatory Standards Compliance D-3

Fast EtherHub-12s User’s Guide

Safety Compliance

Underwriters Laboratories Inc.

Important!

Before making connections, make sure you have the correct Cord Set.

Check it (read the label on the cable) against the following specification list.

Operating Voltage Cord Set Specifications

120 Volts UL Listed/CSA Certified Cord Set

Minimum 18 AWG
Type SVT or SJT three conductor cord
Maximum length of 15 feet
Parallel blade, grounding type attachment plug rated 15A, 125V

240 Volts (For North America) UL Listed/CSA Certified Cord Set

Minimum 18 AWG
Type SVT or SJT three conductor cord
Maximum length of 15 feet
Tandem blade, grounding type attachment plug rated 15A, 125V

240 Volts (For Europe only) Cord S e t with H0 5 V V - F c o r d having t h ree conductors with minimum

diameter of 0.75 mm
IEC-320 receptacle
Male plug rated 6A, 250V

2

The unit will automatically select the setting that matches the input voltage connected.
Therefore, no additional adjustments are necessary when connecting it to any input
voltage within the range marked on the rear panel.

D-4 Regulatory Standards Compliance

Fast EtherHub-12s User’s Guide

Sicherheitshinweise

1. Die Steckdose muß sich in der Nähe des Gerätes befinden und leicht zugänglich sein.

2. Zum Reinigen den Stecker aus der Steckdose ziehen. Beim Reinigen keine
Flüssigreiniger oder Sprays verwenden, sondern ein angefeuchtetes Tuch.

3. Das produkt gerät nicht in Naßräu me oder in der Nähe von
Wasser benutzen, wie z.B. Badezim mer, Schwimm bad, Spü lbeck en u s w.. Das Eindringen
von Wasser kann zur Zerstörung des Gerätes führen.

4. Das produkt gerät nicht auf ein er u ns tabilen Un terlag e, wie z.B. Rollwagen, Gestell usw.,
aufstellen. Es könnte herunterfallen und Verletzungen oder Beschädigungen von Mensch
und Gerät verursachen.

5. Die Belüftungsöffnungen nicht blockieren oder auf falscher Ober-fläche, wie Bett,
Sofa usw., stellen. Durch die Blockierung kann es zur Zerstörung des Gerätes durch
Überhitzung kommen.

6. Versuchen Sie niemals dieses Gerät selbst zu warten, da beim Öffnen oder Abnehmen
des Gehäuses die Gefahr eines elektrischen Schlages besteht.

7. Keine Gegenstände auf das Anschlußkabel stellen, damit es nicht durch scharfe Kanten
zerstört werden kann.

8. Keinerlei Gegenstände durch die Öffungen in das Gerät stecken, da es dadurch sonst
zu Kurzschlässen kommen kann.

9. Bei Störungen des Gerätes den Wartungsdienst verständigen.

10. Bei Reperaturen dürfen nur Orginalersatzteile oder Bauteile mit gleichen
Eigenschaften verwendet werden. Andere Bauteile können Feuer, elektrischen Schlag
oder andere Gefahren verursachen.

11. Nach Beendigung von Wartungsarbeiten oder Reperaturen durch den Kundendienst
sollte die Sicherheitsprüfung durchgeführt werden.

12. Bei längerem Stillstand des Gerätes, ist diese von der Versorgungs- spannung zu
trennen. Dies verhindert eine Besch÷digung des Gerätes durch eine Überspannung in
der Zuleitung.

13. Der arbeitsplatzbezogene Lärmschutzpegel nach DIN 45 635 ist kleiner 70dB (A).

Regulatory Standards Compliance D-5

Appendix E: Product Support Services

Product Registration

Fill in the Owner Registration Card and mail it to Accton Technology Corporation.
Accton will keep your record and inform you of any new Accton unit developments.

Problem Report

If problems occur during unit operation, please check the adapter configuration settings,
cables, connectors, network terminators, hardware compatibility and other network
components.

Write a description of the problem, including what problems occurred, when they
occurred, duration of the problems, the unit number, serial number, hardware, software
and the DOS version that you are using. Then contact your dealer or Accton Technology
Corporation for assistance.

Hardware Repair Service

You must get an RMA (Return Materials Authorization) number before returning any
hardware for repair. To obtain this number please inform Accton of your company
name, address, unit name and model number, contact person, telephone number, and a
problem description list. If your unit is under repair warranty you must also give your
purchase date. Carefully pack your hardware. If possible, use the original carton. Mark
the RMA number on the carton and send it to your dealer.

Product Support Services E-1

Fast EtherHub-12s User’s Guide

After repair, Accton will inform you of the date of delivery and the exact amount due.
Please send the payment by T/T (Telegram Transfer), and Accton will send you the
fixed component after receiving payment. With or without warranty, if the hardware is
found to be free of defects, you will only be charged for testing and handling.

Bulletin Board Service (BBS)

• In countries other than the U.S., call 886-3-5770-654 to reach Accton Taiwan’s

modem line. Modems with 14400 through 2400 baud are supported. Choose 8 data
bits, 1 stop bit and no parity. Standard VT100 terminal emulation is supported

• In the United States, call 408-452-8828 to reach the Accton USA’s BBS line.

Modems with 14400 through 2400 baud are supported. Choose 8 data bits, 1 stop bit
and none parity. Standard VT100 terminal emulation is supported.

Interactive Fast Fax (U.S.A. office)

Printed technical documentation can be FAX’ed to your FAX machine, 24-hours a day.

• Call 408-452-8811 to reach Accton’s interactive Fast FAX service. You will need a

Touch-Tone phone and a FAX machine (or equivalent). Choose document 911 for a
listing of technical bulletins.

E-2 Product Support Services

Fast EtherHub-12s User’s Guide

Technical Support

Your dealer or installer is the person who understands your network and Accton units.
If neither is available to help you, Accton technical support engineers are available by
FAX, mail or phone.

• Send your technical questions by FAX to:

International Headquarters: 886-3-5770-267
USA Headquarters: 408-452-8988

• To obtain software upgrades connect via ftp to ftp.accton.com.tw

• Send your technical questions by email to [e-mail]

• Mail your technical questions to:

International Headquarters

Accton Technology Corporation
Attn: Technical Support
No. 1 Creation Road III
Science-based Industrial Park
Hsinchu 300, Taiwan, R.O.C.

International Headquarters

(Monday through Friday,
8 am to 6 p.m.):
886-3-5770-270

Product Support Services E-3

USA Headquarters

Accton Technology
Corporation
Attn: Technical Support
1962 Zanker Road,
San Jose, CA 95112, U.S.A.

During local business hours, call:

USA Headquarters

(Monday through Friday,
7 am to 5 p.m. Pacific Time):
408-452-8900 or 800-926-9288

Fast EtherHub-12s User’s Guide

Limited Warranty

Accton warrants to the original owner that the product delivered in this package will be free from
defects in material and workmanship for the lifetime of the product. For the warranty to apply, you
must register your purchase by returning the registration card indicating the date of purchase and
including proof of purchase. There will be a minimal charge to replace consumable components, such
as fuses, power transformers, and mechanical cooling devices. The warranty does not cover the product
if it is damaged in the process of being installed. Accton recommends that you have the company from
whom you purchased this product install it.

THE ABOVE WARRANTY IS IN LIEU OF ANY OTHER WARRANTY, WHETHER EXPRESS,
IMPLIED OR STATUTORY, INCLUDING BUT NOT LIMITED TO ANY WARRANTY OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR ANY WARRANTY
ARISING OUT OF ANY PROPOSAL, SPECIFICATION OR SAMPLE. ACCTON SHALL NOT BE
LIABLE FOR INCIDENTAL OR CONSEQUENTIAL DAMAGES. ACCTON NEITHER ASSUMES
NOR AUTHORIZES ANY PERSON TO ASSUME FOR IT ANY OTHER LIABILITY.

Customer Remedies

If the product is found to be defective within the first two years from the later of date of purchase or

date of manufacture, Accton’s entire liability and your exclusive remedy for any breach of warranty,
shall be, at its option, to repair or replace the product at no charge except as set forth below. If the
product is found to be defective after two years from the later of date of purchase or date of
manufacture, Accton will charge a process and handling fee, provided that you deliver the product along
with a return material authorization (RMA) number either to the company from whom you purchased it
or to Accton. Accton warrants the repaired or replaced product to be free from defects in material and
workmanship for the remainder of the original product’s warranty period. Consumable components are
warranted only for two years.

E-4 Product Support Services

Fast EtherHub-12s User’s Guide

Return Process

Before you may return any Accton product to Accton, you must request an RMA number by calling,

FAXing or writing Accton’s Service Department at the address listed below. If you ship the product,
you must assume the risk of damage or loss in transit. You must use the original container (or the
equivalent) and pay the shipping charge. Accton may replace or repair the product with either a new or
reconditioned product, and the returned product becomes Accton’s property. At Accton’s sole
discretion, Accton will issue a credit for either a comparable replacement Accton product or credit the
original purchase price towards the purchase of any Accton product for any unrepairable, defective
product.

This warranty does not cover replacement of products damaged by abuse, accident, misuse, neglect,
alteration, repair, disaster, improper installation or improper testing.

ACCTON SHALL NOT BE HELD LIABLE FOR ANY LOSS OF PROFITS, LOSS OF USE,
INCIDENTAL, CONSEQUENTIAL OR SPECIAL DAMAGES CAUSED BY THE USE OF THIS
PRODUCT OR INABILITY TO USE IT, EVEN IF THE COMPANY OR ACCTON HAS BEEN
ADVISED OF SUCH LIABILITY OR OTHER SPECIAL CLAIMS.

If you purchased this product in the USA, be aware that some states do not allow limitations on how
long an implied warranty lasts, so the above limitations may not apply to you. Some states do not allow
the exclusion or limitation of incidental or consequential damages, so the above limitations or
exclusions may not apply to you. This warranty gives you specific legal rights and you may have other
rights which vary from state to state. All parts or components contained in this product are covered by
Accton’s Limited Lifetime Warranty for this product. The product may contain fully tested, recycled
parts, warranted as if new.

For warranty information:
All territories except North and South America:

Accton Technology Corporation, International Headquarters
No. 1, Creation Rd. III, Science-based Industrial Park, Hsinchu 300, Taiwan, R.O.C.
Phone: [phone] Fax: [phone] BBS: 886-3-5770-654

North and South America:

Accton Technology Corporation, USA Headquarters
1962 Zanker Road, San Jose, CA 95112, U.S.A.
Phone: [phone] Fax: [phone] BBS: 408-452-8828

Product Support Services E-5

Accton Offices

Accton Technology Corporation

International Headquarters,

No. 1 Creation Rd. III,

Science-based Industrial Park,

Hsinchu 300, Taiwan, R.O.C.

Hsinchu: Phone: [phone],

Fax: [phone]

BBS: 886-3-5770-654

Taipei: Phone: [phone] to 9

Fax: [phone]

Accton USA,

1962 Zanker Road,

San Jose, CA 95112, USA

Phone: [phone]

Fax: [phone]

BBS: 408-452-8828

FAST FAX: [phone]

Accton UK,

The Mill Horton Road,

Stanwell Moor,

Staines. Middx. TW19 6BJ United Kingdom

Phone: [phone]

Fax: [phone]

Accton Australia,

Level 6, 10 Help Street

Chatswood, N.S.W. 2067

Australia

Phone: [phone]

Fax: [phone]

BBS: 61-2-9410-9862

Internet: http://www.accton.com.au

Accton Japan,

Kano Bldg. 7F,

1-25-1 Nishi-Gotanda,

Shinagawa-ku,

141 Tokyo, Japan

Phone: [phone]

Fax: [phone]

Fast EtherHub-12s User’s Guide

Ordering Information

• Fast EtherHub-8s

(EH3042-TX)

• Fast EtherHub-12s

(EH3012-TX)

• Fast EtherHub-12se

(EH3012-TF-SC) or
(EH3012-TF-ST)

E-6 Product Support Services

Fast Ethernet Hub with 8 100BASE-TX ports

Fast Ethernet Hub with 12 100BASE-TX ports

Fast Ethernet Hub with 12 100BASE-TX ports,
and 1 100BASE-FX port (SC or ST type port)

Glossary

100BASE-TX

IEEE’s specifications for 100 Mbps Ethernet using twisted-pair cable (100W Cat. 5 STP
or UTP). The maximum length of cable for a point-to-point connection is 100 meters.

Collision

A condition in which two packets transmitted over a medium interfere with each other.
Their interference makes both signals unintelligible. The transmitting devices have to
halt transmission for a random period of time before trying to send data again.

Configuration

The way to set up a computer, server, or local area network.

Connection

A logical binding between two or more users of an interconnection service.

Daisy-Chain Port

An MDI RJ-45 port used to cascade compatible devices in a daisy-chain configuration
using straight-through twisted-pair cable. To cascade two devices, either run a connec­tion from the daisy-chain port on one device to a station port on the other device, or
cascade the two devices by running crossover cable between MDI-X station ports on
both devices.

Ethernet

A network communication system developed and standardized by DEC, Intel, and
Xerox, using baseband transmission, CSMA/CD access and logical bus topology, and
coaxial cable. The successor IEEE 802.3 standard provides for integration into the OSI
model and extends the physical layer and media with repeaters and implementations that
operate on fiber optics, broadband, and twisted-pair.

Glossary 1

Fast EtherHub-12s User’s Guide

Fast Ethernet

100 Mbps network communication system based on Ethernet and the CSMA/CD access
method.

IEEE 802.3 Standard

Standard for the physical and electrical connections in local area networks developed by
the IEEE. The IEEE 802.3u standard covers these same issues for 100 Mbps networks.

LED

Light emitting diode on the front panel of the hub used for monitoring a hub or network
condition. An LED display corresponds to a hub condition.

Local Area Network (LAN)

A group of interconnected computers and support devices.

MDI Port (Medium Dependent Interface)

MDI is the IEEE standard for the twisted-pair interface to 10BASE-T (or 100BASE­TX). This RJ-45 port can be used with straight-through cable to connect the hub to a
network interconnection device, such as another hub or a switch. Pin-out assignments
are shown in Appendix B.

MDI-X Port (Medium Dependent Interface - Crossed)

This RJ-45 port, which crosses the receive and transmit signals internally, can be used
with straight-through cable to connect the hub to any device that has a standard network
interface (e.g., workstation, server or router). Pin-out assignments are shown in
Appendix B.

RJ-45 Connector

Most common terminator for twisted-pair wiring.

2 Glossary

Fast EtherHub-12s User’s Guide

Shielded Twisted-Pair (STP)

100W Category 5 twisted-pair wire covered with an external aluminum-foil or woven­copper shield designed to reduce excessive noise pick up or radiation. The STP cable
refered to in this manual is also sometimes called screened twisted-pair (ScTP). Its
impedance is 100
confused with the older 150

Wand has the same pin assignment as UTP. This cable should not be

Wcable type designed by IBM.

Star Topology

Physical connections for this hub are limited to a star configuration (i.e., similar to a hub
and spoke arrangement). This topology also requires that only one path exists between
any two nodes, and that data transmitted by any node is concurrently available to all
other nodes within the same local network (i.e., immediate collision domain).

Station Port

The MDI-X port can be used for connecting the hub to any device that has a standard
network interface (e.g., workstation, server or router). For port 12, the selector switch
must be set to
compatible hub or a switch.)

MDI-X. (This port can also be connected to an MDI port on another

Unshielded Twisted-Pair (UTP)

Cable composed of insulated wires twisted together to reduce electrical interference;
used in common telephone cord.

Glossary 3

Index

A

Accton's Fast EtherHub-12s • 1-1
Automatic Partitioning • 1-3
Automatic Polarity Detection • 1-3

C

Cable Length

Precise Cable Length Budgeting • 2-4

Simplified Cable Length Constraints • 2-4
Certification • C-1
Class II Repeater • 2-5, 3-3
Configuring the Network • 3-1
Connecting Multiple Hubs • 3-2
Connecting the Hub System • 2-2

Connection, Verifying • 2-6
Crossover Cable • B-1

D

Daisy-Chain Port

Usage • 3-2
Distance Limit for Fast Ethernet Cabling • 2-3

E

EMI Certification • D-1
Ethernet Ports • 4-5

F

Fast EtherHub-12s • 1-1
FCC Warning • D-1

Front Panel • 4-1

G

Guidelines for Multiple Hub Configuration •

3-3

H

Hardware Description • 4-1

I

IEEE 802.3u Standard • 2-5, 3-1
Indicator Panel • 4-1
Installation Requirements • 2-1
Installing the System • 2-1
Inter-hub Cabling Limit • 3-3
Introduction to Fast Ethernet • 1-1

J

Jabber Lock-up • 1-3

L

LED Indicators

Alert • 4-2
Collision% • 4-3
Link • 2-6, 4-4
Partition • 4-4
Power • 4-2
Traffic • 4-5
Utilization% • 4-3

Limited Warranty • E-4

Index 1

Fast EtherHub-12s User’s Guide

M

Maximum Cable Length • 2-4
MDI Daisy-chain Port • 3-2

N

Network Connection

MDI Daisy-Chain Port • 2-3

MDI-X Station Port • 2-2

P

Port and Cable Assignments • B-1
Port Status Indicators • 4-4
Power Cord Specifications • D-4
Power Socket • 4-6
Product Features • 1-2
Product Support Services • E-1

Accton Offices • E-6

Bulletin Board Service • E-2

Hardware Repair Service • E-1

Interactive Fast Fax • E-2

Ordering Information • E-6

Technical Support • E-3
Providing Power to the Hub • 2-5

Certification • C-1
Interfaces • C-1
Media Supported • C-1
Power System • C-1

Standards Conformance • C-1
Stand-alone Configuration • 3-1
Standards Compliance • D-1

T

Troubleshooting • 4-5

Configuration • A-3

Hub Indicators • A-1

Installation • A-2

Power and Cooling • A-2
Twisted-pair Cable

Category 3,4,5 • 2-2, A-2

V

Verifying Port Status • 2-6
Verifying System Operation • 2-6

R

Rear Panel • 4-6
Repeater Delay • 2-5, 3-3

S

Safety Compliance • D-4
Specifications

2 Index

EH3012-TX
150114-101
E0197-R02