A twisted pair cable is made by placing two distinct insulated wires together in a twisted arrangement and running them parallel to each other. The use of two wires twisted with each other helps to decrease crosstalk and electromagnetic interference (EMI). Twisted pair cable is widely used in various kinds of data and voice infrastructures.
In balance pair action, both wires carry same but opposite signal and the difference between two signals is detected by destination. Noise sources (especially Electromagnetic) introduce signals into the wires by coupling of magnetic or electric field and incline to couple with both wires equally. The noise therefore produces a common mode signal which is canceled at the receiving end because of 90 degree twist within the wire, when the difference signal is taken. The twist rate (correspondingly called pitch of the twist, typically defined in twists per meter) provides specification for a given type of twisted pair cable. When adjacent pairs have same twist rate, identical conductors of the unlike pairs may repeatedly lie next to each other, partially cancel the benefits of differential mode, due to this reason it is normally specified that, at least for cables containing a few number of pairs, the twist rates must vary. There are two types of twisted pair cable, an unshielded twisted pair (known as UTP) and a shielded twisted pair or STP, are used for different kinds of installations. UTP is commonly applied for Ethernet installations, while STP is used in different kinds of networks to prevent electromagnetic interference and cross talk caused by EMI. STP cable can also offer grounding in the network.
Provides very low cost for computer networking purposes
Cross talk is reduced
Electrical noise into or out of cable is minimized
Easy to handle and installation.