Twisted pairs

Twisted pairs, as in Figure 1.23, is a cable that contains four twisted pairs of copper; a total of eight wires, each with a specified color. The single wires are twisted around each other forming twisted pairs, and then the pairs are twisted around each other forming the cable; and that is done to reduce electromagnetic interference (EMI) and cross-talk. Usually, it is available in two types: unshielded twisted pair (UTP), and shielded twisted pair (STP). Mainly, it is used for designing LANs. The maximum distance that the twisted pairs medium can successfully carry a signal in an Ethernet network is 100 m.