Transmission Medium Data can be transmitted through a variety of medium. The simplest form a transmission medium is Twisted Pair Cable which is typified by a pair of wires twisted together and then lightly coated for protection. This medium is the least expensive, and only reliable in a protected environment. Co-axial Cable essentially uses a similar medium however the wiring is more heavily coated, so that it can be effective when used outdoors. Many telephone transmission configurations use this type medium.
Microwave transmission uses sound waves to transmit data communications signals.
The wider the bandwidth, the more data is permitted to travel across the communications media. Imagine a two lane highway - each lane permitting one direction of travel. Now imagine a 12 lane highway with six lanes traveling in either direction. The number of cars that control over that highway within a given period of time would be much greater than the number of cars that control over the two lane highway over the same period of time. Broadband technology enables a faster transmission using a variety of advanced media.