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CCNA 1 and 2 Companion Guide, Revised (Cisco Networking Academy Program) part 96

Cisco Networking Academy Program CCNA 1 and 2 Companion Guide, Revised part 96 is the Cisco approved textbook to use alongside version 3.1 of the Cisco Networking Academy Program CCNA 1 and CCNA 2 web-based courses. The topics covered provide you with the necessary knowledge to begin your preparation for the CCNA certification exam (640-801, or 640-821 and 640-811) and to enter the field of network administration. | B appen_a.fm Page 919 Tuesday May 20 2003 4 54 PM Tools of the Trade 919 Installation Support Tools A cable installer also will find other tools useful. A measuring wheel is used to estimate the length of a cable run see Figure A-24 . The wheel has a counter mounted on the side. An installer simply rolls the wheel down the intended path of the cable. When the end is reached the counter indicates the distance. Figure A-24 Measuring Wheel Cable installers also need tools and materials for cleaning up the job site. Brooms dust pans and vacuums make the cleanup process go quickly. Cleanup is one of the final but important steps in completing a cabling project. A shop vacuum is designed for industrial or heavy-use jobs. Fish Tape One device specifically designed to make the retrieval of wires inside a wall a quick and easy process is fish tape see Figure A-25 . Fish tape can be run through walls or conduits. After running the fish tape to its intended destination of some convenient partway point secure the cable to be pulled to the end of the fish tape. Retrieve by pulling and winding. The desired cable will come with it. For cabling work a fiberglass fish tape is safer than a steel one. Also most seasoned cable installers pull a string along with their cables. This provides a convenient way to pull extra cables later. appen_a.fm Page 920 Tuesday May 20 2003 4 54 PM 920 Appendix A Structured Cabling Figure A-25 Fish Tape Cable Tree During the rough-in phase cable trees jacks and rollers are used to support cable reels to make laying the cable faster and easier and to prevent injuries. A cable tree supports a number of small reels of cable see Figure A-26 . This enables the cable installer to pull multiple runs of cable simultaneously. Because all cables terminate at the telecommunications room a cable tree would be set up in the staging area. After cable is pulled to a jack location the other end is cut from the reel and pulled into the telecommunications room. Figure .