Short range wired transmission can provide high reliability communication and high data rate as well. Although optical fibers (OFs) guarantee very high reliability communications, good OFs (e.g., single mode OFs) are extremely expensive and their short range use is typically limited to those applications that demand it.

Since copper wires are cheaper than OF, very flexible and easy to install, they are usually preferred for wired connections. Further, since copper is an excellent medium for cable lengths up to hundred meters, copper cables represent the link structure at the forefront for communications among personal computers and local area networks (LANs).