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HOW do I get the files from my laptop computer to my desktop computer? And which cable do I use to accomplish this goal? If these questions have plagued your sleepless nights, you're in luck! This article will de-mystify network patch cable secrets so that you can connect your computers and transfer those pesky files-without screaming at the cables. The activity described here can also offer your students a great hands-on opportunity for working with the tools, techniques, and media used in computer networking.
Cable Particulars
The cables used in computer networking can seem a little overwhelming at first. Let's start by examining the commonly used types. The main three used for networking today are coaxial cable, fiber optic cable, and twisted-pair cable.
Coaxial cable ("coax") was the first media used for networking (Photo 1). Though adequate in the past, coax is fast becoming obsolete due to the increase in network speeds. Coaxial cable was desirable for its self-shielding properties and fairly long cable distances (200-500 meters). However, newer media overshadows its positive attributes.
The second media type, fiber optic cable, is a modern problem solver for network designers (Photo 2). Typically, fiber optic is found at the heart of a network, the backbone (high bandwidth connection), and is used for extremely long cable run distances. The high cost of fiber optic is justifled because of its immunity to electromagnetic interference and lightning, as well as the long unboosted cable run distances (1-10 Km) it makes possible.
The media connection normally used for connecting the desktop computer is the last media type, the most popular media of the day, twisted-pair cable (Photo 3). At first glance, twisted-pair cable may look like phone cable. However, note the following differences.
First, phone cable normally contains four wires, and twisted-pair cable contains eight. Second, the wires in the twisted-pair cable are paired, TX (transmit wire) with RX (receive wire), and those pairings are twisted together. Phone cable is not paired, and its wires lay flat inside the cable insulation. These may seem like minor differences, but they make fast data transmission with the twisted-pair cable possible.
The construction of twisted-pair cable makes use of self-shielding techniques. With the TX wire and RX wire twisted together, the magnetic fields...