Patent ID: 6973094
Filing Date: 2005-12-06
Classification: H04L

Abstract:
1. A packet-switched multiple-access network system having a shared communication channel connecting a plurality of stations, each station comprising: a network interface, the network interface transmitting packets to the shared communication channel and receiving packets from the shared communication channel; a carrier sense for sensing whether the shared communication channel is in use and for preventing transmissions by the station when the shared communication channel is in use; a collision detect for detecting the occurrence of a collision between a first transmission by the station and a second transmission on the shared communication channel, and for causing a collision notification signal to be transmitted to the shared communication channel by the station when a collision is detected; a slot timer for dividing a time period following successful completion of a transmission on the shared communication channel into a plurality of contention slots in order of priority; a controller for monitoring a priority of a data packet awaiting transmission and for delaying transmission of the data packet awaiting transmission until a contention slot corresponding to the priority of the data packet; wherein, when the station detects a collision of the data packet in a contention slot, the station enters a contention protocol to resolve the collision between contending stations for that contention slot; and wherein, when the station receives a collision notification signal from the shared communication channel and the station was not involved in the collision, the station reduces the priority of the data packet awaiting transmission so as to withhold transmission until completion of the contention protocol between contending stations.