Twisted Pair

Twisted Pair Wires are as the name suggests, pairs of copper wires twisted together. They carry signals in form of electricity through the copper wires. Twisting of cables help reduce the noise affecting hte cables and thus increases the maximum length fo the cables without the need of repeaters, etc.

Unshielded Twisted Pair (UTP)

 * Consists of copper wires covered by PVC or other insulators.


 * This is the most commonly used medium today, due ot its wide application in telephone systems.
 * Can carry both voice as well as data.
 * UTP are flexible, cheap adn easy to install.
 * Electronics Industries Association (EIA) has developed standards for UTP cables.

Categories of UTP

 * 1) Basic cable used in telephone system. Suitable for voice and very low speed data communication.
 * 2) Suitable for voice and data communication upto speed of 4 Mbps.
 * 3) Carry voice and data up to 10 Mbps. The most regularly used category in telephone networks today. Need at least three twists per foot.
 * 4) Similar to category 3, but has increased capacity of up to 16 Mbps.
 * 5) Can handle speeds of up to 100 Mbps.

Shielded Twisted Pair (STP)

 * This is similar to UTP but with an additional metal shield present overthee wire. A final plastic cover is also used.
 * The metal cover prevents the penetration of electromagnetic noise. It also eliminates crosstalk. Crosstalk is an effect wherein one wire picks up signals travelling on a nearby wire.