Extended DQRAP (XDQRAP) A Cable TV Protocol Functioning as a Distributed Switch

1 Abstract1 XDQRAP, an extension of DQRAP (Distributed Queueing Random Access Protocol), is a multiple access protocol that like DQRAP offers a throughput equal to the offered traffic up to a load of one and with a lesser delay than any other multiple access protocol. XDQRAP, as does DQRAP, provides this performance for all values of "a", i.e., the size of the network is immaterial. XDQRAP also functions as a distributed switch in that the segments of variable length packets in a slotted system do not require encapsulation, i.e., an adaptation layer is not required. XDQRAP is described and simulation results are presented. The argument is presented that community networks should utilize random access of a shared medium on the inbound channel(s) at the MAC layer and that these community networks should utilize XDQRAP to support all voice and data transmission.