A local area network has a plurality of data stations 1 each connected to a common data channel 2 via a receiver 5, a transmitter 6 and a directional coupler 7, wherein, in order to resolve contention for the channel and at the same time providing each station with statistically an equal chance of gaining...http://www.google.com/patents/US4564838?utm_source=gb-gplus-sharePatent US4564838 - Data communication network and method of communication
