What is a token passing?

Token passing is a media access method by which collisions are prevented. A collision results when two computers transmit a signal at the same time.

Collisions are eliminated under token passing because only a computer that possesses a free token (a small data frame) is allowed to transmit. The token passing method also allows different priorities to be assigned to different stations on the ring. Transmissions from a stations with higher priority take precedence over stations with lower priority.

Token passing works best in an environment where a relatively large number of shorter data frames are being transmitted. (As opposed to CSMA/CD which works best in an environment where relatively fewer, longer data frames are being transmitted.)

Token passing is used on Token Ring and ArcNET networks.