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An exemplary point-to-multipoint network including an upstream headend facility and a plurality of downstream network terminals ("NTs") employs a contention-based multi-slot MAC permit protocol for upstream request transmission, wherein each NT compiles a congestion rank for each upstream slot posit

An exemplary point-to-multipoint network including an upstream headend facility and a plurality of downstream network terminals ("NTs") employs a contention-based multi-slot MAC permit protocol for upstream request transmission, wherein each NT compiles a congestion rank for each upstream slot position based on feedback information supplied by the headend. At such time as an NT wishes to attempt an upstream response to an multi-slot permit, it excludes the slot position having the highest rank for purposes of selecting an upstream response slot, and chooses among the others at random. If there are two or more slots having an equally high rank, the NT still excludes only one of the slots, based on a predetermined order of priority calculated at random from the NT's unique physical ID. If an NT is not successful with its initial response in the selected slot position, it will randomly select a waiting period of zero, one or two multi-slot permit cycles before attempting another upstream transmission. If, before attempting a re-transmission, the NT observes an intervening collision between two or more other NTs in the same upstream response slot, it will increase its waiting period by yet another two permit cycles.

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[ What is claimed:] [10.] In a communication network comprising a headend and a plurality of network terminals in communication with the headend over a shared communication medium,wherein the headend periodically transmits a multi-slot upstream transmission permit to the network terminals authorizin

[ What is claimed:] [10.] In a communication network comprising a headend and a plurality of network terminals in communication with the headend over a shared communication medium,wherein the headend periodically transmits a multi-slot upstream transmission permit to the network terminals authorizing any one of a specified group of network terminals to transmit a response to the headend in any one of a preset number of corresponding upstream slots,and wherein the headend transmits feedback information to the network terminals following each multi-slot upstream transmission permit, the feedback information containing for each respective upstream slot an indication as to whether a transmission was attempted by any network terminal in response to the respective permit and, if so, whether the transmission was successfully received by the headend,a method for a respective network terminal to transmit a response to a multi-slot upstream transmission permit, comprising the step of:compiling an ongoing rank for each respective upstream slot based on the feedback information transmitted by the headend;determining which upstream slot has a highest rank; andrandomly selecting an upstream slot from any of the preset number of slots except that slot determined to have the highest rank.