NetWorth Series 1000 EtherNext MicroHub Lite

MicroHubInstallation Guide

TM

DisclaimerNetWorth, Inc. makes no representations or warranties withrespect to the contents or use of this manual, and specificallydisclaims any express or implied warranties of merchantability orfitness for any particular purpose. Further, NetWorth, Inc.reserves the right to revise this publication and to make changesto its content, at any time, without obligation to notify any personor entity of such revision or changes.

FCC WarningComputing devices and peripherals manufactured by NetWorthgenerate, and can radiate, radio frequency energy, and if notinstalled and used in accordance with the instructions in thismanual, may cause interference to radio communications. Suchequipment has been tested and found to comply with the limits fora Class A computing device pursuant to Subpart J of Part 15 ofthe FCC Rules, which are designed to provide reasonableprotection against radio interference when operated in acommercial environment. Operation of this equipment in aresidential area is likely to cause interference, in which case theuser at his own expense will be required to take whatevermeasures necessary to correct the interference.

Some components may not have been manufactured byNetWorth, Inc. If not, NetWorth has been advised by themanufacturer of the component that it has been tested andcomplies with the Class A computing device limits as describedabove.

Copyright 1990, 1992, 1994 NetWorth, Inc. All rights reserved.No part of this publication may be reproduced, photocopied,stored on a retrieval system, or transmitted without the expressprior written consent of the publisher.

Series 1000 MicroHub Lite

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TrademarksNetWorth, Inc. has made every effort to supply trademarkinformation about company names, products, and servicesmentioned in this book. Trademarks indicated below were derivedfrom various sources.

AT&T is a registered trademark of American Telephone andTelegraph Communications.

EtherNext is a registered trademark of NetWorth, Inc.

IBM is a registered trademark of International Business MachinesCorporations.

Ungermann-Bass is a registered trademark of Ungermann-Bass,Inc.

Product InformationFor NetWorth product information or technical support, please call214-929-1700 between the hours of 8:00 a.m. and 6:00 p.m.(CST).

You can access NetWorths BBS 24 hours a day at 214-929-4882.The modem supports up to 14.4 baud and is configured for noparity, 8 data bits, and 1 stop bit.

Series 1000 MicroHub Lite

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Contents

Ethernext MicroHub Products .........................................MicroHub UTP 9-Port 10BASE-T Hub ...........................................MicroHub BNC 8-Port 10BASE-T Hub ...........................................Whats In the MicroHub Kit?...........................................................Technical Specifications .................................................................Additional Equipment .....................................................................

Designing a MicroHub Network.......................................Sample Network Configurations.....................................................

Single Hub Model ....................................................................Multiple Hub Model ..................................................................BNC Model ..............................................................................Maximum Repeater Path Model ..............................................

Installing a MicroHub........................................................Switch Settings...............................................................................

Uplink Switch ...........................................................................BNC Enable Switch .................................................................

MicroHub Placement Considerations .............................................Mounting the MicroHub ..................................................................

Mounting the MicroHub Vertically Onto Wallboard ..................Mounting the MicroHub Vertically Onto Wood .........................Mounting the MicroHub Horizontally Onto Wallboard ..............Mounting the MicroHub Horizontally Onto Wood.....................

Connecting Power ..........................................................................Domestic..................................................................................International .............................................................................

Making Connections to the MicroHub ............................................

v

Twisted-Pair Wire Specifications .............................................MicroHub-To-Network Station Connections ............................MicroHub-To-MicroHub Connections with UTP.......................Making Thin Ethernet Connections .........................................

MicroHub LEDs.................................................................MHUB09 (Non-BNC Version) ........................................................MHUB09-B (BNC Version).............................................................

Glossary ............................................................................

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Introduction

The EtherNext MicroHub Lite offers the most in 10BASE-Tsimplicity and sophistication. The compact, lightweight designmakes the MicroHub cost-efficient and easy to install. TheMicroHub is a full 802.3 multiport repeater and is compatible withthe IEEE 802.3 10BASE-T standard for connection to unshieldedtwisted-pair (UTP) wiring. Also, the MicroHub and is fullycompatible with the EtherNext Series 4000 intelligent wiringconcentrators. NetWorth supplies a full product line to allow youto expand your network as your needs grow.

The MicroHub includes built-in port management capabilities. Itautomatically partitions noisy segments and also can detectbroken cable segments with the link integrity feature.

You can configure Port 8 as an output port for connecting toanother MicroHub (via the UPLINK switch).

The MicroHub Lite is available in two versions MHUB08 andMHUB08-I. Both versions include eight UTP 10BASE-Tconnections. The MHUB08 uses a domestic power supply and theMHUB08-I uses an international power supply (210-250 VAC 50hz.)

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Figure 1-1 Series 1000 MicroHub (MHUB08)

Series 1000 MicroHub Lite NetWorth, Inc.

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MicroHub Kit ContentsThe MicroHub kit, shown in Figure 1-2, contains the followingitems:

A MicroHub multiport repeaterB MicroHub Installation GuideC Power Module (international version includes built-in

mounting brackets)D Two No. 6 x 1 inch wall-mounting screwsE Two wall anchorsF Two nylon shoulder washersG Two MicroHub mounting clipsH Two No. 4-40 x 3/16 inch attachment screwsI Two No.6 x 1 inch power supply mounting screws

(international versions only)

Figure 1-2 MicroHub Kit Contents

NetWorth, Inc. Series 1000 MicroHub Lite

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If any item is missing or damaged, return the kit to the originalplace of purchase to obtain a replacement.

NOTEThe international version contains a power module withan IEC power connector which requires an IEC powercord. You can place the international power module ona table top or you can mount it on a wall (wall-mountingscrews included).


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Technical SpecificationsDimensions

Inches (HxWxD): 1.4 x 6.25 x 4.95 Centimeters (HxWxD): 35 x 160 x 126

Power RequirementsDomestic: 100 to 130 VAC .21 amp max load 60 Hz

International: 210 to 250 VAC .1 amp max load 50 Hz

Storage Environment 40F to 151F

40C to 66C 5% to 95% humidity (non-condensing) 0 to 30,000 feet altitude 0 to 9 kilometers altitude

Operating Environment 32F to 120F

0C to 49C 5% to 95% humidity (non-condensing)

Cooling Convection


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Technical Specifications - (Cont)Mounting

Wall

Tabletop

Connectors 8 Modular RJ45 jacks (non-keyed) DC power input jack

LED Indicators 8 Green Link Status LEDs 1 Green Power LED 1 Green Receive Active LED 1 Yellow Collision LED

Switches Uplink (Port 8)

Additional EquipmentNetWorth can provide most of the components you need to installyour Ethernext MicroHub. However, you should obtain tools, testequipment, and twisted-pair interconnect hardware from a thirdparty.

ToolsThe following tools are required to wall-mount the MicroHub:

Phillips screwdriver Hammer

Drill with: 18-inch (3mm) bit for mounting into wood; or 316-inch(5mm) bit for mounting into drywall


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Designing a MicroHub Network

Sample Network ConfigurationsThe following figures represent several configurations for anEtherNext MicroHub LAN.

Single Hub ConfigurationFigure 3-1 shows one MicroHub connected to network stationswithin a 100 meter radius. You can place the MicroHub in a wiringcloset or next to network stations. In this example, Port 8 of theMicroHub is configured as an input port to accommodate aworkstation connection.

Multiple Hub Configuration

2

Figure 2-1 Single-Hub Configuration

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Figure 3-2 shows three MicroHubs connected with unshieldedtwisted-pair wiring to form a larger network.

MicroHub A is the primary concentrator. MicroHub B and MicroHub C are uplinked to MicroHub A. MicroHub B and MicroHub C each have Port 8 configured as

output ports.

Figure 2-2 Multiple-Hub Configuration


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Maximum Repeater Path ModelEthernet limits the total number of repeaters that can be in thepath between any two network stations. The EtherNext MicroHuballows up to five repeaters between any two network stations. Fora maximum configuration, you can use MicroHubs to build anetwork of up to 576 network stations. Figure 3-3 shows anexample of a maximum transmission path.

Figure 2-3 Maximum Repeater Path Configuration


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Installing the Microhub

Setting the Uplink SwitchThe uplink switch helps simplify twisted-pair wiring betweenMicroHubs. Typically, the MicroHubs RJ-45 jacks function asinput ports for workstation connections. Connecting an input portfrom one hub to an input port of another hub would normallyrequire a special crossover cable that reverses the receive andtransmit pairs. The MicroHubs uplink switch eliminates the needfor crossover cables by reconfiguring Port 8 as an output port.

Figure 4-1 shows the proper position for the uplink switch whenconnecting Port 9 (Port 8 on the BNC Model) to a primary Hub.

3

Figure 3-1 Uplink Switch Setting for Primary Hub Connection

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Figure 4-2 shows the proper position for the uplink switch whenconnecting Port 8 to a network station.

Figure 3-2 Uplink Switch Setting for Station Connection


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MicroHub Placement ConsiderationsYou can set a MicroHub horizontally on a level surface (such as atable top, filing cabinet or desktop) or mount it vertically orhorizontally on a wall.

The location for the MicroHub must meet the followingenvironmental, electrical and spatial requirements.

Environmental RequirementsTemperature: 32 to 120 degrees F0 to 49 degrees C

Humidity: 5% to 95% non-condensing

Altitude:0 to 10,000 feet

Electrical RequirementsThere must a commercial non-switched, 3-pronged, groundedpower outlet within six (6) feet (1.8 meters) cord distance of theMicroHub. If there is no convenient location for the MicroHubwithin this distance, use a power strip or grounded extension cordto extend the range of the power transformer cable.

The power requirements for a MicroHub are:

Domestic:

Voltage: 100 to 130 VACFrequency: 60 Hz ower: .21 amps max

International:

Voltage: 210 to 250 VACFrequency: 50 HzPower: .1 amps max


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WARNINGDo not use a 3-to-2 pronged adapter at the outlet; doing somay result in electrical shock and/or damage to theMicroHub.

Spacial Requirements

MicroHub Dimensions: Inches (HxWxD) - 1.4 x 6.25 x 4.95 Centimeters (HxWxD) - 35 x 160 x 126

Connections to the front of the MicroHubLeave at least 2 feet in front of the adapter to allow access for UTPconnections.

Air Circulation If you mount the MicroHub vertically on a wall, allow 2 inches

(5.1 centimeters) of clearance above and below the MicroHub. If you set a MicroHub on a level surface or mount the MicroHub

horizontally on a wall, allow 2 inches (5.1 centimeters) on eachside of the MicroHub.

Do not stack MicroHubs on top of each other.


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Mounting the MicroHubYou can mount the MicroHub on a wallboard or a wood surface(stud, telephone board, etc.) using the supplied hardware.

To mount the MicroHub, you need a Phillips screwdriver, a drill,and a set of drill bits.

If you will not mount the MicroHub on a wall, skip to ConnectingPower later in this chapter.

To mount a MicroHub, follow these steps:

1. Determine whether you are mounting the MicroHub vertically(Figure 4-4) or horizontally (Figure 4-5).

Figure 3-3 Vertical MicroHubMount

Figure 3-4 Horizontal MicroHubMount


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2. Determine whether you are mounting the MicroHub ontowallboard between studs or onto a solid wood surface.

Mounting the MicroHub Vertically onto Wallboarda. Select the appropriate size drill bit to drill holes for the wall

anchors.

b. Drill a hole 1.5 inches (3.8 centimeters) above where you wantthe bottom of the MicroHub to be located.

c. Drill a second hole 4.25 inches (10.8 centimeters) above thefirst hole.

d. Insert the wall anchors and lightly tap them into place until theyare flush with the wall.

e. Insert the wall mount screws through the nylon shoulderwashers.

f. Insert the screws into the wall anchors.

g. Tighten the screws until the shoulder of the washer is flush withthe wall (Figure 4-6).

Top View

Wall Washer

Figure 3-5 Inserting Screw into Wall


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h. Attach the mounting clips to the MicroHub as shown inFigure 4-7.

i. Slide the MicroHub over the heads of the wall- mount screwsuntil it is snug.

Figure 3-6 AttachingMounting Clips

Figure 3-7 Sliding MicroHubOver Wall Screws


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Mounting the MicroHub Vertically onto Wooda. Select the appropriate size drill bit to drill holes for the

wall-mount screws.

b. Drill a hole 1.5 inches (3.8 Centimeters) above where you wantthe bottom of the MicroHub to be located.

c. Drill a second hole 4.25 inches (10.8 Centimeters) above thefirst hole.

d. Insert the wall mount screws through the nylon shoulderwashers.

e. Insert the screws into the holes you just drilled.

f. Tighten the screws until the shoulder of the washer is flush withthe wall (Figure 4-9).

Figure 3-8 Inserting Screw into Wood


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g. Attach the mounting clips to the MicroHub as shown in Figure4-10.

h. Slide the MicroHub over the heads of the wall- mount screwsuntil it is snug.

Figure 3-9 AttachingMounting Clips

Figure 3-10 Placing theMicroHub on the Wall


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Mounting the MicroHub Horizontally onto Wallboarda. Select the appropriate size drill bit to drill holes for the wall

anchors.

b. Drill a hole .3 inches (1 Centimeter) to the right of where youwant the left side of the MicroHub to be located.

c. Drill a second hole 5.5 inches (14 Centimeters) to the right ofthe first hole.

d. Insert the wall anchors and lightly tap them into place until theyare flush with the wall.

e. Insert the wall mount screws through the nylon shoulderwashers.

f. Insert the screws into the wall anchors.

g. Tighten the screws until the shoulder of the washer is flush withthe wall (Figure 4-12).

Top View

Wall Washer

Figure 3-11 Inserting Screw into Wallboard


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h. Remove two screws from the back plate of the MicroHub asshown in Figure 4-13.

i. Attach the mounting clips to the MicroHub with the twopreviously removed screws as shown in Figure 4-14.

Figure 3-12 Removing Screws from Backplate

Figure 3-13 Attaching Mounting Clips


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j. With the modular jacks facing the floor, slide the MicroHub overthe heads of the wall-mount screws until it is snug.

Figure 3-14 Sliding MicroHub Over Wall Screws


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Mounting the MicroHub Horizontally onto Wooda. Select the appropriate size drill bit to drill holes for the

wall-mount screws.

b. Drill a hole .3 inches (1 Centimeter) to the right of where youwant the left side of the MicroHub to be located.

c. Drill a second hole 5.5 inches (14 Centimeters) to the right ofthe first hole.

d. Insert the wall mount screws through the nylon shoulderwashers.

e. Insert the screws into the holes you just drilled.

f. Tighten the screws until the shoulder of the washer is flush withthe wall.


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g. Remove two screws from the backplate of the MicroHub asshown in Figure 4-17.

h. Attach the mounting clips to the MicroHub with the twopreviously removed screws as shown in Figure 4-18.

Figure 3-16 Removing Screws from Backplate

Figure 3-17 Attaching Mounting Clips to MicroHub


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i. With the modular jacks facing the floor, slide the MicroHub overthe heads of the wall-mount screws until it is snug.

Figure 3-18 Placing MicroHub Over Wall Screws


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Connecting PowerDomestic

1. Plug the female connector on the power module cable into thepower connector on the side of the MicroHub. The lip on thepower connector faces the top of the MicroHub (the labeledhorizontal surface as shown in Figure 4-20).

2. Insert the 3-pronged plug on the power module into a groundedpower receptacle on the wall, a power strip, or a groundedextension cord.

Figure 3-19 Connecting Power to the MHUB08


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3. When the power module is plugged in, be sure that the powerLED as shown in Figure 4-21 is on.

Figure 3-20 MicroHub Power LED


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International1. Place the international power module on a flat surface or

mount it to a wall near the MicroHub using the power supplymounting screws.

2. Plug the female connector on the power module cable into thepower connector on the side of the MicroHub. The lip on thepower connector faces the top of the MicroHub (the labeledhorizontal surface as shown in Figure 4-22).

Figure 3-21 Connecting Power to the MHUB08-I


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3. Plug the female end of a three-pronged IEC power cable intothe power transformer (Figure 4-23).

4. Insert the 3-pronged male plug on the IEC power cable into agrounded power receptacle on the wall, a power strip, or agrounded extension cord.

Figure 3-22 Connecting IEC Power Cable


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5. When the power transformer is plugged in, be sure that thepower LED as shown in Figure 4-24 is on.

Figure 3-23 MicroHub Power LED


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Making Connections to the MicroHubThis chapter describes how to make a simple direct connectionbetween a MicroHub and a network station. To utilize existingin-house wiring, or to examine other cross connect options, referto the EtherNext Series 4000 Installation Guide for additionalinformation.

Twisted-Pair Wire Specifications The twisted-pair wiring must meet minimum requirements toensure long-term LAN reliability. If the wiring does not meet thefollowing specifications and requirements, it may be necessary toinstall new twisted-pair wiring.

Must be unshielded twisted-pair wiring. Two pairs are required. Depending on building codes, different insulation materials

may be required. Plenum-rated or TEFLON-coated wiring maybe required in some areas.

The wire should be meet the following specs: Solid copper, not stranded

Nominal capacitance: < 16pF/ft

Nominal impedance: 100 Ohm

Nominal attenuation: < 11.5db

The gauge should be between 18 and 26 AWG (American WireGauge). Twenty-four gauge wiring is found in most standardtelephone installations.

The wiring must meet the maximum distance requirements(100 meters standard, 200 meters extended). This distancemust include all cross-connect wire, wire in the walls, and anydrop cables from wall plates to workstations (see next sectionto verify length).


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Note: Maximum distances may be less for any UTP cable rununderground, in conduit, or in large cable bundles.

In general, the MicroHub is compatible with all AT&T Type Dwiring (D-Inside wiring) and AT&T PDS wiring. The MicroHubwill also operate with IBM Type 1 (2 inner conductors) wiring.

The wiring must be in good condition and the insulation shouldnot be frayed or worn.


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MicroHub-to-Network Station ConnectionsThe simplest way to connect to a MicroHub is with AT&T Type Dwiring (D-Inside wiring). D-Inside Wiring is convenient to usewhen connecting network stations that are co-located with theMicroHub. There are two types of D-Inside wiring that will workwith the MicroHub: DW8 which is stranded wire and more flexible,and D8W which has solid conductors and is less flexible.

Typically you would use DW8 for shorter runs (less than 50 ft.)within the same room. D8W wire is used for longer runs and isusually run through ceilings and/or in the walls.

A modular cord is D-Inside wiring with RJ-45 plugs on each end.The connection between a MicroHub and a workstation is straightthrough 4-pair D-Inside wiring (only two pairs are actually used bythe MicroHub) as shown in Figure 4-25. NetWorth supplies someD-Inside wiring and additional wiring products can be obtainedfrom national distributors such as Graybar.

In this type of cable, the wire connected to Pin 1 must be twistedwith the wire connected to Pin 2 and the wire connected to pin 3must be twisted with the wire connected to Pin 6 as shown inFigure 4-26. Pins 4, 5, 7 and 8 are reserved for telephone andother services.

Figure 3-24 D-Inside Wiring


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Each MicroHub RJ-45 jack has the following pin-out inaccordance with the 10BASE-T standard:

MicroHub Pin Number Signal Description

1236

Receive +Receive Transmit +Transmit

A straight-through cable from the MicroHub to a network stationusing the pair combinations shown above will provide theappropriate 10BASE-T connection.

Figure 4-28 shows a MicroHub-to-network station connection.Simply plug one end of the modular cord into a 10BASE-Tequipped network station and plug the other end of the modularcord directly into a MicroHub Port. Remember, the maximum

Figure 3-26 RJ-45 Pin-Out Configuration

Figure 3-25 D-Inside Wiring Plug Pin # Designations


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end-to-end distance is 100 meters unless both ends of theconnection support extended distance.

Once the network station and the MicroHub are connected and

powered on, the corresponding LINK LED on the MicroHubshould light. If the LINK LED does not light, be the cablingconnections and pair orientation are correct.

Note: Some manufacturers of 10BASE-T Network Interface Cardsdo not provide a Link Integrity signal until the software driver hasbeen loaded and the card initialized. Check with the manufacturerof your NICs to determine if driver initialization is a prerequisite toproper Link Integrity operation (NetWorth NICs do not have to beinitialized to provide the Link Integrity signal).

Figure 3-27 MicroHub-To-Network Station Connection


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CAUTION: NEVER USE GREY SATIN STATION CABLES FORCONNECTING TO A MICROHUB. THIS IS A FLAT CABLETHAT IS TYPICALLY USED FOR CONNECTINGTELEPHONES TO WALL JACKS AND IS INCOMPATIBLEWITH 10BASE-T SYSTEMS.

MicroHub-to-MicroHub Connections With UTPThe same wiring requirements as found in the previous sectionMicroHub-To-Network Station Connections also apply toMicroHub-to-MicroHub connections.

As noted previously, one of the MicroHubs must have Port 9 (Port8 on the BNC model) configured as an output by setting the UplinkSwitch to the Out position as shown in Figure 4-29.

Figure 3-28 MicroHub-To-MicroHub Connection


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Making Thin Ethernet ConnectionsAs shown in Figure 4-30, MicroHub model number MHUB09-Bhas a BNC connector for thin Ethernet connections. This BNCconnector can be used to connect to any thin Ethernet segmentand can also be used to daisy chain MicroHubs.

You will need a T-connector to make the connection and, if theMicroHub is the last node on the segment, you must terminate theT-connector with a 50-ohm termination plug.

Once the MicroHub is fully connected to the thin Ethernetsegment, you can set the BNC ENABLE switch to the ON positionas shown in figure 4-31.


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MicroHub LEDs

MHUB09 (non-BNC version)Figure 5-1 shows the LED array for the MicroHub model number

MHUB09 (non-BNC version). This MicroHub has 9 green LinkStatus LEDs, 1 green POWER LED, 1 green ACTIVITY LED, and1 yellow COLLISION LED.

Link Status LEDs - There is a Link Status LED associated witheach 10BASE-T Port. When a good connection has been madewith either a powered network station or another Hub, the greenLED associated with that Port will illuminate. If this cable segmentshould break, the associated green Link LED will extinguish.

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Figure 4-1 Link Status LEDs

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POWER LED - The green POWER LED will illuminate when thepower module is plugged into the MicroHub and plugged into an

AC power source.

ACTIVITY LED - The green ACTIVITY LED will blink every time apacket is received on any of the 9 UTP Ports.

COLLISION LED - The yellow COLLISION LED will blink everytime a packet collision occurs. Collisions occur in every Ethernetsystem and do not necessarily reflect a system problem.

Figure 4-2 POWER/ACTIVITY/COLLISION LEDs


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MHUB09-B (BNC version)Figure 5-3 shows the LED array for the MicroHub model numberMHUB09-B (BNC version). This MicroHub has 8 green LinkStatus LEDs, 1 green BNC Active LED, 1 green POWER LED, 1green ACTIVITY LED, and 1 yellow COLLISION LED.

Link Status LEDs - There is a Link Status LED associated witheach 10BASE-T Port. When a good connection has been madewith either a powered network station or another Hub, the greenLED associated with that Port will illuminate. If this cable segmentshould break, the associated green Link LED will extinguish.

BNC Active LED - The green LED associated with the BNCconnector will blink every time a packet is received on the thinEthernet segment.

POWER LED - The green POWER LED will illuminate when thepower module is plugged into the MicroHub and plugged into anAC power source.

ACTIVITY LED - The green ACTIVITY LED will blink every time apacket is received on any of the 8 UTP Ports or the BNC Port.

COLLISION LED - The yellow COLLISION LED will blink everytime a packet collision occurs. Collisions occur in every Ethernetsystem and do not necessarily reflect a system problem.


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Glossary

10BASE-2An IEEE Standard (802.3) for local area networks. Complyingnetworks must be able to carry information at a rate of 10megabit/second over distances up to 185 meters of thin coaxialcable.

10BASE-5An IEEE Standard (802.3) for local area networks. Complyingnetworks must be capable of carrying information at a rate of 10megabit/second over distances up to 500 meters of thick coaxialcable.

10BASE-TAn IEEE Standard (802.3) for local area networks. Complyingnetworks must be able to carry information at a rate of 10megabit/second over distances up to 100 meters of unshieldedtwisted-pair cable.

66-Type Wiring EnvironmentAlso called Premises Distribution System (PDS). The AT&Twiring system in which the telephones, nodes and othercommunications devices connect to the cross-connect block.

110-Type Wiring Environment Also called Premises Distribution Systems (PDS). The AT&Twiring system in which the telephone, nodes and othercommunications devices can be easily added and rearranged withmodular wiring components and patch cords.

802.3An IEEE standard for Ethernet local area networks based onCarrier Sense Multiple Access with Collision Detection

Glossary - 1

(CSMA/CD), which includes 10BASE2, 10BASE 5 and10BASE-T.

Adapter A device that supports the interconnection of different sizes and/ortypes of plugs.

Attachment Unit Interface (AUI)The interface between the medium attachment unit (MAU) and anode within a local area network (LAN).

BackplaneThe data bus connections used to interconnect differentcommunication modules inside a network concentrator.

BNCA thin Ethernet coax connector.

Bridged Tap (Stub)A cable (or cord) connected to another cable (or cord) at a pointother than its end. Such a tap causes impairment of networksignal transmissions.

Carrier SenseThe monitoring of a local area network by a node to determine ifanother node is transmitting.

Coaxial CableA cable with at least one transmission line consisting of twoconductors, an inner conductor and an outer conductor, insulatedfrom one another by a dielectric. Coaxial cable carriers higherfrequencies than twisted pair cable and offers a broaderbandwidth. It is commonly used to transmit video signals, but canalso be used for certain high-speed data applications.


Glossary - 2

CollisionA condition that occurs when two nodes attempt to transmit on thenetwork at the same time. When a collision occurs, both nodesrecognize the collision, stop transmission, wait for a random timeinterval, and then attempt to retransmit.

ConcentratorA device that provides connectivity between data terminals in anetwork.

ConductorA medium, such as copper wire, that can carry electrical current.

ConfigurationThe layout of nodes and components in the network.

Cross-Connect BlockA panel on which the leads of station cable are mounted so atechnician, other wiring craftsperson, or a system administratorcan make connections between the communications deviceswired to the cables.

DCEData communications equipment.

DTEData terminal equipment.

DielectricA substance that does not conduct electrical current.

Equipment RoomAn enclosed space where voice- and data-common equipmentcircuit administration is performed.


Glossary - 3

Ethernet TransceiverA device used in an Ethernet local area network to couple dataterminal equipment to other transmission media.

Fiber AdapterA hardware device used to convert System 4000 network signalsbetween electrical signals on twisted-pair wire and light pulsestransmitted on fiber optic cable.

Fiber Optic CableA transmission medium consisting of a core of glass surroundedby strengthening material and a protective jacket. Signals aretransmitted as light pulses and introduced into the optical fiber bylaser or light emitting diodes (LEDs).

JabberA condition where the transmission of network signals exceedsthe maximum allowable transmission time. Jabber may be causedby a faulty node or wiring connection.

LEDLight emitting diode.

Link IntegrityA diagnostic tool that continuously checks wiring for breaks,opens or shorts, and notifies the user if those conditions exist.

Local Area Network (LAN)A data communications network consisting of electronicdevicessuch as host computers, file servers and personalcomputersoften connected via twisted-pair wire or coaxialcable. Typically, the network is limited to a single premise.


Glossary - 4

Medium Attachment Unit (MAU)A device used in a data station to couple the data terminalequipment (DTE) to the transmission medium.

Megabit One million bits.

Modular CordA cord containing four twisted pairs of wires with a modular plugon one or both ends.

ModuleThe component that provides connectivity ports for the LAN.Modules are installed in larger systems called concentrators.

Network Interface Card (NIC)A plug-in expansion board that enables computers to send andreceive data through the network.

NodeA computer, workstation or other device in a network.

PartitionThe disconnecting of a node from a LAN.

Plenum Cord A communications cord with fire-retardant insulation, generallyused in suspended ceilings and other places where air circulatesback to the buildings air-conditioning system.

PortA concentrator connection used to connect PCs and other nodedevices to the network.


Glossary - 5

Primary Hub (Concentrator) The hub in a room or wiring closet to which all other hubs areconnected. If a room or a wiring closet has only one hub, it also isconsidered a primary hub.

Satellite ClosetA room where cross-connect hardware is located and wherecabling from wall jacks is terminated.

Secondary Hub (Concentrator)Any hub whose OUT jack is connected to an IN jack of a primaryhub in the same room or wiring closet.

TelcoA 25-pair polarized connector that is used to consolidate multiplevoice or data lines.

Tip/Ring System The AT&T wiring environment that designates tip and ring as thefunctions of two conductors within each wire group of a 25-pairstation cable.

Transceiver Cable A cable used to connect two hardware devices, one having aD-type DCE connector and the other having a D-type DTEconnector. Also called an AUI cable.

Unshielded Twisted Pair (UTP) WireTwo insulated copper wires twisted together to reduce thepotential for signal interference between pairs. In cables greaterthan 25 pairs, the twisted pairs are grouped and bound togetherin a common cable sheath. Twisted pair cable is the most commonof transmission media.


Glossary - 6

Wiring Environment Any building communications wiring system. See 66-Type WiringEnvironment.

Wiring ClosetA room, closet or cabinet where station cable is terminated oncross-connect blocks and where the building communicationssystem can be administered.


Glossary - 7

707055-0012/94

ContentsChapter 1--IntroductionMicroHub Kit ContentsTechnical Specifications

Chapter 2--Designing a MicroHub NetworkSample Network ConfigurationsMicroHub Placement ConsiderationsEnvironmental RequirementsElectrical RequirementsSpatial RequirementsConnecting PowerMaking Connections to the MicroHubTwisted-Pair Wire SpecificationsMicroHub-to-Network Station ConnectionsMicroHub-to-MicroHub Connections With UTPMaking Thin Ethernet ConnectionsMHUB09-B (BNC Version)

GlossaryManual Part Number/Publication Date

NetWorth Series 1000 EtherNext MicroHub Lite

Documents

microhub network

microhub utp

microhub bnc

microhub kit

radio interference

baset hub

radio communications

hub model