CCNA 1. Networking Basics v3.1.1 Student Lab Manual (796248), страница 8
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Pin2 will be the same as Pin 2, and so on. The cable will be wired to either TIA/EIA T568B or T568Astandards for 10BASE-T Ethernet, which determines what color wire is on each pin. T568B, alsocalled AT&T specification, is more common in the U.S., but many installations are also wired toT568A, also called ISDN.Prior to starting the lab, the teacher or lab assistant should have a spool of Category 5 UnshieldedTwisted Pair (UTP) cable, RJ-45 (8-pin) connectors, an RJ-45 crimping tool and an Ethernet / RJ-45continuity tester available. Work individually or in teams. The following resources will be required:1-3•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 straight-through or crossover type cables,T568A or T568B•Wire cuttersCCNA 1: Networking Basics v 3.1 - Lab 3.1.9cCopyright 2003, Cisco Systems, Inc.Cabling Pin-out Information for T568BPin #12345678Pair #22311344FunctionTransmitTransmitReceiveNot usedNot usedReceiveNot usedNot usedWire ColorWhite/OrangeOrangeWhite/GreenBlueWhite/BlueGreenWhite/BrownBrownUsed with10/100BASE-TEthernet?YesYesYesNoNoYesNoNoUsed with100BASE-T4 and1000BASE-TEthernet?YesYesYesYesYesYesYesYesDiagram showing both T568A and T568B cabling wire colorsUse the preceding table and diagram to create a T568B patch panel cable.
Both cable ends shouldbe wired the same when looking at the conductors.Step 1Determine the distance between devices or device and plug. Add at least 30.48 cm (12 in.) to thedistance. The maximum length for this cable, according to TIA/EIA structured wiring standards is 5 m(16.4 ft), although this can vary. Standard lengths are 1.83 m (6ft) and 3.05 m (10 ft).Step 2Cut a piece of stranded Category UTP cable to the desired length. Use stranded cable for patchcables because it is more durable when bent repeatedly.
Solid wire is used for cable runs that arepunched down into jacks.Step 3Strip 5.08 cm (2 in.) of jacket off of one end of the cable.Step 4Hold the four pairs of twisted cables tightly where jacket was cut away. Reorganize the cable pairsinto the order of the T568B wiring standard. Take care to maintain as much of the twists as possiblesince this provides noise cancellation.2-3CCNA 1: Networking Basics v 3.1 - Lab 3.1.9cCopyright 2003, Cisco Systems, Inc.Step 5Hold the jacket and cable in one hand and untwist a short length of the green and blue pairs.Reorder the pairs to reflect the T568B wiring color scheme. Untwist and order the rest of the wirepairs according to the color scheme.Step 6Flatten, straighten, and line up the wires.
Trim them in a straight line to within 1.25 to 1.9 cm (1/2 to¾ in.) from the edge of the jacket. Be sure not to let go of the jacket and the wires, which are now inthe proper order. Minimize the length of untwisted wires because sections that are too long and nearconnectors are a primary source of electrical noise.Step 7Place an RJ-45 plug on the end of the cable, with the prong on the underside and the orange pair tothe left side of the connector.Step 8Gently 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. This provides for stress relief and toensure that all wires are in the correct order. If the jacket is not inside the plug, the plug will not beproperly gripped and will eventually cause problems. If everything is correct, crimp the plug hardenough to force the contacts through the insulation on the wires, completing the conducting path.Step 9Repeat Steps 3 through 8 to terminate the other end of the cable.
Use the same scheme to finish thestraight through cable.Step 10Test the finished cable. Have the instructor check the finished cable. How is it possible to tell if thecable is functioning properly?3-3CCNA 1: Networking Basics v 3.1 - Lab 3.1.9cCopyright 2003, Cisco Systems, Inc.Lab 3.1.9d Rollover Cable ConstructionObjective•Build a Category 5 or Category 5e Unshielded Twisted Pair (UTP) console rollover cable.•Test the cable for continuity and correct pin-outs, the correct wire on the right pin.BackgroundThis will be a 4-pair "rollover" cable. This type of cable is typically 3.05 m (10 ft) long but can be aslong as 7.62 m (25 ft).
A rollover cable can be used to connect a workstation or dumb terminal to theconsole port on the back of a Cisco router or switch. Both ends of the cable built will have RJ-45connectors on them. One end plugs directly into the RJ-45 console management port on the back ofthe router or switch. Plug the other end into an RJ-45-to-DB9 terminal adapter. This adapter convertsthe RJ-45 to a 9-pin female D connector for attachment to the PC or dumb terminal serial (COM)port. A DB25 terminal adapter is also available to connect with a PC or dumb terminal. This adapteruses a 25 pin connector. The following picture shows a rollover console cable kit that ships with mostCisco devices.This cable is called a rollover because the pins on one end are all reversed on the other end asthough one end of the cable was rotated or rolled over.
In the last lab when building the straightthrough cable, putting the second RJ-45 on upside down would have made a rollover cable insteadof the straight through cable.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, an RJ-45 crimping tool and a continuity tester available.Work individually or in teams. The following resources will be required:•1-3One 3.05 to 6.1 m (10 to 20 ft) length of Category 5 cabling per person or per teamCCNA 1: Networking Basics v 3.1 - Lab 3.1.9dCopyright 2003, Cisco Systems, Inc.•Four RJ-45 connectors, two are extra for spares•RJ-45 crimping tools to attach the RJ-45 connectors to the cable ends•An RJ-45 to DB-9 female terminal adapter, available from Cisco•Cabling continuity tester•Wire cuttersStep 1Use the table as a reference to help create a rollover console cable.Signal Legend: RTS = Request To Send, DTR = Data Terminal Ready, TxD = Transmit Data, GND= Ground (One for TxD and one for RxD), RxD = Receive Data, DSR = Data Set Ready, CTS =Clear To Send.Step 2Determine the distance between devices, then add at least 30.48 cm (12 in.) to the distance.
Makethe cable about 3.05 m (10 ft), unless connecting to router or switch from a greater distance. Themaximum length for this cable is about 8m (approx 25 ft).Step 3Strip 5.08 cm (2 in.) of jacket off of one end of the cable.Step 4Hold the 4 pairs of twisted cables tightly where jacket was cut away. Reorganize the cable pairs andwires into the order of the T568B wiring standard. They can be ordered in any sequence, but use theT568B sequence to become more familiar with it.Step 5Flatten, straighten, and line up the wires, then trim them in a straight line to within 1.25 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.2-3CCNA 1: Networking Basics v 3.1 - Lab 3.1.9dCopyright 2003, Cisco Systems, Inc.Step 6Place an RJ-45 plug on the end of the cable, with the prong on the underside and the orange pair tothe left side of the connector.Step 7Gently 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.Step 8If everything is correct, crimp the plug hard enough to force the contacts through the insulation onthe wires, thus completing the conducting path.Step 9Repeat steps 2 through 8 to terminate the other end of the cable, but reversing every wire asindicated in the table above.
Pin 1 to pin 8, pin 2 to pin 7, pin 3 to pin 6 and so on.a. Alternate Method – Arrange the wires into the order of the T568B wiring standard. Place a RJ-45plug on the end with the prong on the top side of the connector. This method will achieve the properreversing of every pair of wires.Step 10Test the finished cable.
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