Cycle Time Properties Of The FDDI Token Ring Protocol

The FDDI Token Ring Protocol controls communication over fiber optic rings with transmission rates in the range of 100 megabits per second. It is intended to give guaranteed response to time-critical messages by using a "timed token" protocol, in which non-critical messages may be transmitted only if recent movement of the token among stations has been sufficiently fast relative to a "target" token rotation time (TTRT).