What is a bus topology?

A bus topology connects each computer (node) to a single segment trunk. A �trunk� is a communication line, typically coax cable, that is referred to as the �bus.� The signal travels from one end of the bus to the other. A terminator is required at each end to absorb the signal so it does not reflect back across the bus.

In a bus topology, signals are broadcast to all stations. Each computer checks the address on the signal (data frame) as it passes along the bus. If the signal�s address matches that of the computer, the computer processes the signal. If the address doesn�t match, the computer takes no action and the signal travels on down the bus.

Only one computer can �talk� on a network at a time. A media access method called CSMA/CD is used to handle the collisions that occur when two signals are placed on the wire at the same time.

The bus topology is passive. In other words, the computers on the bus simply �listen� for a signal; they are not responsible for moving the signal along.

A bus topology is normally implemented with coaxial cable