CCNA 1. Networking Basics v3.1.1 Student Lab Manual (796248), страница 9
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Have the instructor check it. How is it possible to tell if the cable isfunctioning properly?3-3CCNA 1: Networking Basics v 3.1 - Lab 3.1.9dCopyright 2003, Cisco Systems, Inc.Lab 3.1.9e Crossover Cable ConstructionObjective•Build a Category 5 or Category 5e Unshielded Twisted Pair (UTP) Ethernet crossover cable toT568B and T568A standards.•Test the cable for continuity and correct pin-outs, correct wire on the right pin.BackgroundThis will be a 4-pair "crossover" cable. A crossover cable means that the second and third pairs onone end of the cable will be reversed on the other end. The pin-outs will be T568A on one end andT568B on the other end. All 8 conductors (wires) should be terminated with RJ-45 modularconnectors.This crossover cable will conform to the structured cabling standards. If the crossover cable is usedbetween hubs or switches, it is considered to be part of the "vertical" cabling.
Vertical cabling is alsocalled backbone cabling. A crossover cable can be used as a backbone cable to connect two ormore hubs or switches in a LAN, or to connect two isolated workstations to create a mini-LAN. Thiswill allow the connection of two workstations or a server and a workstation without the need for a hubbetween them. This can be very helpful for training and testing. To connect more than twoworkstations, a hub or a switch will be needed.Prior to starting the lab, the teacher or lab assistant should have a spool of Category 5 or Category5e UTP cable, RJ-45 (8-pin) connectors, a RJ-45 crimping tool and an Ethernet / RJ-45 continuitytester available. Work individually or in teams.
The following resources will be required:•One 0.6 to .9 m (2 to 3 ft) length of Category 5 cabling per person or team•Four RJ-45 connectors, two are extra for spares•RJ-45 crimping tools to attach the RJ-45 connectors to the cable ends•Ethernet cabling continuity tester which can test crossover type cables, T568A to T568B•Wire cuttersStep 1Create a crossover cable using the following tables and diagrams. One end of the cable should bewired to the T568A standard.
The other end should be wired to the T568B standard. This crosses thetransmit pairs and the receive pairs, the second and third pair, to allow communication to take place.Only four wires are used with 10BASE-T or 100BASE-TX Ethernet.1-4CCNA 1: Networking Basics v 3.1 - Lab 3.1.9eCopyright 2003, Cisco Systems, Inc.T568A CablingPin #Pair #FunctionWire ColorUsed with10/100BASE-TEthernet?Used with100BASE-T4 and1000BASE-TEthernet?13TransmitWhite/GreenYesYes23TransmitGreenYesYes32ReceiveWhite/OrangeYesYes41Not usedBlueNoYes51Not usedWhite/BlueNoYes62ReceiveOrangeYesYes74Not usedWhite/BrownNoYes84Not usedBrownNoYesT568B CablingPin #Pair #FunctionWire ColorUsed with10/100BASE-TEthernet?Used with100BASE-T4 and1000BASE-TEthernet?12TransmitWhite/OrangeYesYes22TransmitOrangeYesYes33ReceiveWhite/GreenYesYes41Not usedBlueNoYes51Not usedWhite/BlueNoYes63ReceiveGreenYesYes74Not usedWhite/BrownNoYes84Not usedBrownNoYesStep 2Determine the distance between devices, or device and plug, and then add at least 30.48 cm (12 in.)to it.
Standard lengths for this cable are 1.83 m (6 ft) and 3.05 m (10 ft).2-4CCNA 1: Networking Basics v 3.1 - Lab 3.1.9eCopyright 2003, Cisco Systems, Inc.Step 3Cut a piece of stranded UTP cable to the desired length. Use stranded cable for crossover cablesbecause it is more durable when bent repeatedly. Solid wire is fine for cable runs that are puncheddown into jacks.Step 4Strip 5.08 cm (2in.) of jacket off one end of the cable.Diagram showing both T568A and T568B cabling wire colorsStep 5Hold the four pairs of twisted cables tightly where the jacket was cut away. Reorganize the cablepairs into the order of the T568B wiring standard.
Take care to maintain the twists since this providesnoise cancellation.Step 6Hold the jacket and cable in one hand. Untwist a short length of the green and blue pairs, andreorder them to reflect the T568B wiring color scheme. Untwist and order the rest of the wire pairsaccording to the color scheme.Step 7Flatten, straighten, and line up the wires. Trim them in a straight line to within 1.25 cm to 1.9 cm (1/2to ¾ in.) from the edge of the jacket. Be sure not to let go of the jacket and the wires, which are nowin order. Minimize the length of untwisted wires because sections that are too long and nearconnectors are a primary source of electrical noise.Step 8Place an RJ-45 plug, prong down, on the end of the cable with the green pair on the left side of theT568A end, and the orange pair on the left side of the T568B end.Step 9Gently push the plug onto wires until the copper ends of the wires can be seen through the end ofthe plug.
Make sure the end of the jacket is inside the plug and all wires are in the correct order. Ifthe jacket is not inside the plug, the plug will not be properly gripped and will eventually causeproblems. If everything is correct, crimp the plug hard enough to force the contacts through theinsulation on the wires, thus completing the conducting path.3-4CCNA 1: Networking Basics v 3.1 - Lab 3.1.9eCopyright 2003, Cisco Systems, Inc.Step 10Repeat steps 4-9 to terminate the other end of the cable using the T568A scheme to finish thecrossover cable.Step 11Test the finished cable. Have the instructor check it.
How is it possible to tell if the cable isfunctioning properly?4-4CCNA 1: Networking Basics v 3.1 - Lab 3.1.9eCopyright 2003, Cisco Systems, Inc.Lab 3.1.9f UTP Cable PurchaseObjective•Introduce the variety and prices of network cabling and components in the market.•Gather pricing information for UTP patch cables and bulk cable.BackgroundPut together a price list for an upcoming cabling project. Gather pricing information for the horizontal(UTP) cabling. If UTP is not used in the immediate area, substitute shielded products.
The itemsinclude the following:•24 – 1 m (3 ft) Category 5 or higher UTP patch cables•24 – 3 m (10 ft) Category 5 or higher UTP patch cables•2 – 15 m (50 ft) Category 5 or higher UTP patch cables•152.4 m (500 ft) UTP compare the price to shielded twisted pair•152.4 m (500 ft) UTP plenumStep 1 Research cable pricingUse at least three sources for pricing.
On the Web try http://www.cdw.com andhttp://www.google.com. Perform searches from those sites looking for Category 5 jumpers,Category 5 patch, and Category 5 bulk. While the CDW site will give prices quickly, the Googlesearch will turn up many interesting things from custom cable building firms to instructions forbuilding cables. Also refer to networking equipment and supplies catalogs.Step 2 Compile a table of the resultsSite, Catalog or Store24 - 1 m (3 ft) Category 5 or higher24 - 3 m (10 ft) Category 5 or higher2 - 15 m (50 ft) Category 5 or higher152.4 m (500 ft) UTP152.4 m (500 ft) shielded twisted pair152.4 m (500 ft) UTP plenum1-1CCNA 1: Networking Basics v 3.1 - Lab 3.1.9fCopyright 2003, Cisco Systems, Inc.Lab 3.2.8 Fiber-Optic Cable PurchaseObjective•Introduce the variety and prices of network cabling and components in the market.•Gather pricing information for fiber patch cables and fiber bulk cable.BackgroundPut together a price list for an upcoming cabling project.
Gather pricing information for the vertical orfiber cabling. Use Multimode (MM) fiber. The items include:•24 – 2 m (6 ft) MM patch cables•24 – 5 m (15 ft) MM patch cables•2 – 15 m (50 ft) MM patch cables•304.8 m (1000 ft) MM fiber optic cableStep 1 Research Cable PricingUse at least three sources for pricing. On the Web, try http://www.cdw.com andhttp://www.google.com. Perform searches from those sites looking for fiber optic jumpers, fiberoptic patch, and fiber optic bulk. While the CDW site will give prices quickly, the Google searchwill turn up many interesting things from custom cable building firms to instructions for buildingcables. Also refer to networking equipment and supplies catalogs.Step 2 Compile a Table of the ResultsSite, Catalog or Store24 - 2 m (6 ft) MM patch cables24 - 5 m (15 ft) MM patch cables2 - 15 m (50 ft) MM patch cables304.8 m (1000 ft) MM fiber optic cable1-1CCNA 1: Networking Basics v 3.1 - Lab 3.2.8Copyright 2003, Cisco Systems, Inc.Lab 4.2.9a Fluke 620 Cable Tester – Wire MapObjective•Learn the wire mapping features of the Fluke 620 LAN CableMeter or its equivalent.•Learn how to use a cable tester to check for the proper installation of unshielded twisted- pair(UTP) Category 5 according to TIA/EIA-568 cabling standards in an Ethernet network.Background / PreparationWire maps can be very helpful in troubleshooting cabling problems with UTP cable.
A wire mapallows the network technician to verify which pins on one end of the cable are connected to whichpins on the other end.Prior to starting the lab, the teacher or lab assistant should have several correctly wired Category 5cables to test. The cables should be both straight-through and crossover. There should also beseveral Category 5 cables created with problems such as poor connections and split pairs to test.Cables should be numbered to simplify the testing process and to maintain consistency.
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