Accton Technology Fast EtherHub-12se User manual

Fast EtherHub-12se
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Installation Manual
Fast EtherHub-12se
Smart Fast Ethernet Hub
with 11 100BASE-TX Ports
and 1100BASE-FX Port

Copyright (c) 1996 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.
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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]
86$+HDGTXDUWHUV
1962 Zanker Road
San Jose, CA 95112
Phone: [phone]
FAX: [phone]
BBS: 408-452-8828
FAST FAX: [phone]
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-TF
150089-101
E1296-R01

Package Contents i
Package Contents
Carefully unpack the contents of the package and verify them against the
checklist given below.
Package Checklist
æFast EtherHub-12se
Model No. EH3012-TF-SC or EH3012-TF-ST
Model EH3012-TF-SC has an SC-type fiber connector.
Model EH3012-TF-ST has an ST-type fiber connector.
æAC power cord (optional)
æFour rubber foot pads
æInstallation manual
æWarranty 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.

Quick Installation iii
Quick Installation
The Fast EtherHub-12se is a Class II repeater. It contains 11 100BASE-TX
Fast Ethernet RJ-45 ports, as well as 1100BASE-FX fiber optic port that
supports connection using standard multimode fiber cable. 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-12se.
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 servers or workstations to the RJ-45 MDI-X station ports. Use
100WCategory 5 STP or UTP cable to connect to the hub, and be sure the
length of any individual twisted-pair connection does not exceed 100 meters.
5. You can connect the hub’s 100BASE-FX port to a workstation, another hub,
or to a collapsed backbone (e.g., a 100 Mbps switch). Use 50/125 mm or
62.5/125 mm fiber optic cables with SC or ST connectors to connect to the
hub. Assuming the maximum cable length of 100 meters is used to connect
various devices to the hub with twisted-pair cable, then the maximum length
you can run a fiber optic link depends on the device type you want to attach
to the hub, as shown in the following table:
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Fast EtherHub-12se User’s Guide
iv Quick Installation
If your twisted-pair connections are less than 100 meters long, then the
length of the fiber optic cable can be extended. Refer the section 'LVWDQFH
/LPLWIRU)DVW(WKHUQHW&DEOLQJ in Chapter 2 for a description of how to calculate
the maximum length of fiber optic cable that can be used in your particular
environment.
6. You can make a cascaded connection to another hub by running straight-
through twisted-pair cable from the daisy-chain port 12 (MDI) on this hub to
any station port (MDI-X) on the another hub (or vice versa). If necessary,
you can also cascade between two station ports using crossover cable. Port 1
can also used to make a fiber optic connection to another compatible hub.
Assuming that the maximum cable length is used for end-node connections,
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 first
calculate the maximum length permitted between each pair of end nodes as
described under the %LW%XGJHW section in Chapter 2 (page 2-4).
7. 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.

About this Guide v
About this Guide
This guide is designed for the experienced network installer. It describes how
to install and operate Accton’s Fast EtherHub. 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 - Product Overview
Brief description of Fast Ethernet, followed by a description of this hub and a
summary of its important features and specifications.
Chapter 2 - Installing the System
Installing a Fast EtherHub and making basic network connections.
Chapter 3 - Configuring the Network
Shows sample network configurations for a local area network.
Chapter 4 - Hardware Reference
Detailed description of indicator panel and ports.
Appendices -
Troubleshooting, cable assignments, and product specifications.

Contents
vii
Chapter 1: Product Overview .................................................1-1
Introduction to Fast Ethernet.....................................................................................1-1
Accton’s Fast EtherHub System.................................................................................1-1
Basic Features............................................................................................................1-2
Chapter 2: Installing the System............................................2-1
Pre-Installation Requirements ...................................................................................2-1
Connecting the Hub System ......................................................................................2-1
Making RJ-45 Connections ..................................................................................2-2
Making Fiber Optic Connections..........................................................................2-2
Distance Limit for Fast Ethernet Cabling .............................................................2-3
Simplified Cable Length Constraints ..............................................................2-3
Precise Cable Length Budgeting.....................................................................2-4
Providing Power to the EtherHub..............................................................................2-5
Verifying Port Status.................................................................................................2-5
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
Precise Guidelines for Configuring Multiple Hubs...............................................3-3
Chapter 4: Hardware Reference.............................................4-1
Front Panel ...............................................................................................................4-1
SmartWatch Indicator Panel.................................................................................4-2
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
Fiber Optic Ethernet Port......................................................................................4-5

Fast EtherHub-12se User’s Guide
viii Contents
Rear Panel ...............................................................................................................4-6
Power Socket........................................................................................................4-6
Appendix A: Troubleshooting ................................................A-1
Diagnosing Hub Indicators........................................................................................A-1
System Diagnostics....................................................................................................A-2
Installation............................................................................................................A-2
Configuration........................................................................................................A-2
Hub Integrity.........................................................................................................A-2
Appendix B: Port and Cable Assignments.............................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 .........................................................................................................D-1
Voluntary Control Council for Interference (VCCI-1) .........................................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
Software Update and Upgrade Service......................................................................E-2
Bulletin Board Service (BBS)...................................................................................E-2
Interactive Fast Fax (U.S.A. office)...........................................................................E-2
Technical Support......................................................................................................E-3

Fast EtherHub-12se User’s Guide
Contents ix
Limited Warranty ......................................................................................................E-4
Customer Remedies..............................................................................................E-4
Return Process......................................................................................................E-5
Accton Distributors ...................................................................................................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 The Fast EtherHub-12se Front Panel .....................................................4-1
Figure 4-2 The Fast EtherHub-12se 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

Product Overview 1-1
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 System
The Fast EtherHub-12se includes 11 100BASE-TX RJ-45 ports, plus an
additional 100BASE-FX fiber optic port. This hubs provides a friendly design
that simplifies installation and network troubleshooting. The SmartWatchTM
indicator panel includes Utilization and Collision rate LEDs, as well as Partition,
Link and Traffic LEDs to ease network management.
The Fast EtherHub-12se 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. They can greatly
improve access both to key servers and to the network backbone. These hubs
not only deliver a vast improvement in network response time, but help you
maintain outstanding performance as your user community continues to grow.

Fast EtherHub-12se User’s Guide
1-2 Product Overview
Basic Features
•Conforms to the IEEE 802.3u repeater specification for 100BASE-TX and
100BASE-FX
•Transmits data at 100 Mbps for demanding applications
•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
•RJ-45 ports for 100BASE-TX connection using unshielded or shielded
twisted pair cable
•Port 12 can serve as an MDI-X station port or as an MDI daisy-chain port
using standard straight-through twisted-pair cable (see Fig. 4-1)
•Includes additional port for 100BASE-FX connection using multimode fiber
optic cable
•Automatically partitions bad ports to protect the network system
•Automatic polarity detection and correction permits automatic adjustment
for wiring errors
•Alert LED shows if fan has failed

Fast EtherHub-12se User’s Guide
Product Overview 1-3
These Fast EtherHubs support the following basic system safeguards:
•This hub features automatic partitioning and reconnection, jabber lockup
protection, and automatic polarity detection for network cabling.
•With automatic partitioning and reconnection, any port is automatically
isolated if excessive collisions occur on it. When the collision rate subsides,
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.

Installing the System 2-1
Chapter 2: Installing the System
This chapter provides information on pre-installation requirements, establishing
network connections, and configuring the system.
Pre-Installation Requirements
Before you start making network connections to the Fast EtherHub-12se, make
sure you can provide the right operating environment, including power
requirements, and proximity to other network devices that are to be connected.
Verify the following installation requirements:
•Power requirements: 100 to 240 VAC at 50 to 60 Hz. The hub’s power
supply automatically detects the input voltage level.
•The hub should be located in a cool dry place, with at least 10 cm. of space
at the front and back for ventilation.
•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
Connecting the Hub System
This hub is a Fast Ethernet repeater for 100BASE-TX networks, with an
additional fiber optic link for connection to any compatible 100BASE-FX device.
The Fast EtherHub-12se has 11 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).
Use twisted-pair cable (100W Category 5 STP or UTP) to connect any RJ-45
MDI-X port to a server/workstation, or to connect the RJ-45 MDI port (i.e., Port
12) to another compatible hub. It also has one additional fiber optic port (Port 1:
SC or ST type). You may use 50/125 or 62.5/125 mm guage multimode fiber
optic cable with SC or ST type connectors (depending on the Fast EtherHub

Fast EtherHub-12se User’s Guide
2-2 Installing the System
model you purchased) to connect any compatible network device to the TX/RX
jacks on the fiber optic port.
Note: The EH3012-TF-SC provides an SC-type fiber connector.
The EH3012-TF-ST provides an ST-type fiber connector.
Making RJ-45 Connections
1. Prepare category 5 straight-through twisted-pair cable (100W) with RJ-45
plugs at both ends.
2. If you are making a connection to a server or workstation (i.e., a dedicated
connection to an end-node device), be sure that it has a properly installed
100BASE-TX network interface card. Attach one end of the cable to an
MDI-X station port on the hub and the other end to the RJ-45 port of the
device’s network interface card.
If you are connecting to a network interconnection device, attach one end of
the cable to Port 12 on the hub (and set the switch to MDI crossover mode,
see Fig. 4-1) and the other end to an MDI-X station port on the other device
(or vice versa). When cascading to devices other than this hub, please refer
to the accompanying documentation for restrictions on cascade size and
cable length
I
Do not plug a phone jack connector into the RJ-45 port. This may damage the hub.
Instead, use only twisted-pair cables with RJ-45 connectors that conform to FCC
standards.
Making Fiber Optic Connections
1. Prepare a fiber optic cable with the required connector types (i.e., SC or ST)
at both ends.
2. If you are making a connection to a server or workstation, be sure it that has
a properly installed 100BASE-FX network interface card. Connect the
RX/TX jacks on the target device to the TX/RX jacks on the hub.

Fast EtherHub-12se User’s Guide
Installing the System 2-3
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.
Simplified Cable Length Constraints
The Fast EtherHub-12se 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 112 meters
for fiber optic 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:
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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.

Fast EtherHub-12se User’s Guide
2-4 Installing the System
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 end-
node devices (e.g., workstations or servers) must be within 100 meters of the
connected hub when using twisted-pair cabling, or within 112 meters when
using fiber optic 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 terms, the maximum length of cabling that
can be run from end-node to end-node is
367m ≥S(repeater equivalent length)
+ S(length of category 5 twisted-pair cable)
+ (0.9 * S(length of fiber optic cable1)) 1 - if fiber is used
This repeater has an inherent delay of 90 bit time or 80 meters of twisted-pair
cable. Taking a daisy chain of two hubs connected with 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 meters 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).

Fast EtherHub-12se User’s Guide
Installing the System 2-5
On the other hand, if two hubs are connected via 100m of fiber optic cabling,
then the total length of remaining cabling that can be used to connect two end-
nodes to hub 1 and 2 respectively is 367m - (2 x 80m) - (0.9 x 100) = 117m.
A more detailed example of calculating the maximum cable length for fiber
optics is included in the section on 3UHFLVH*XLGHOLQHVIRU&RQILJXULQJ0XOWLSOH+XEV in
Chapter 3.
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 Fig. 4-2), and the other end into a power outlet.
2. Check the LED marked Power on the front panel to see if it is on. The unit
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.
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.)
•/LQN Indicates that the port has established valid network connection.
•7UDIILF Indicates traffic traversing the port.
•3DUWLWLRQ 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.

Fast EtherHub-12se User’s Guide
2-6 Installing the System
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 cable to be sure it does not exceed 100
meters. Be sure the length of fiber optic cable does not exceed 112 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.
Note: All repeater hubs provide common access to a shared medium, and therefore
operate at half duplex. At half duplex, the maximum cable length that can be used
for fiber optics is 112 meters. Only devices (e.g., a switch or router) which support
dedicated links can operate at full duplex. When operating these device types at full
duplex, the maximum cable length for fiber optics is 2 kilometers.
•Verify that the workstation’s adapter card is functioning properly 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 7URXEOHVKRRWLQJ in Appendix A.

Configuring the Network 3-1
Chapter 3: Configuring the Network
The Fast EtherHub-12se allows great flexibility in configuring your network.
You can use it in a stand-alone or multiple hub configuration. Moreover, this
hub also provides a fiber optic port which can be used to connect to any
compatible 100BASE-FX device (e.g., a switch or router). Some of the
common applications for this hub are described in this chapter.
Stand-Alone
These hubs 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 and 112 meters for fiber optic cable.
Figure Chapter 3:-1 Stand-Alone Configuration
Connecting Multiple Hubs
In a multiple hub configuration, the maximum overall segment length for inter-
hub 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.