Introduction of Transmission Media Transmission media can be defined as physical path between transmitter and receiver in a data transmission system. Transmission media are of two types. Guided Unguided Guided : Transmission capacity depends mainly on the medium, the length, and whether the medium is point-to-point or multipoint (e.g. LAN). Examples are co-axial cable, twisted pair, and optical fiber. Twisted Pair Cable: The oldest, least expensive, and most commonly used media The two wires are typically ``twisted'' together in a helix to reduce interference between the two conductors. Twisting decreases the interference between adjacent pairs in a cable ( two straight parallel wires tend to act as an antenna and pick up extraneous signals.) Typically, a number of pairs are bundled together into a cable by wrapping them in a tough protective sheath. Can carry both analog and digital signals.. Quite hig...
