Throughput and fairness in a hybrid channel access scheme for ad hoc networks

A novel hybrid channel access scheme that combines sender-initiated collision-avoidance handshakes is proposed for multi-hop ad hoc networks. The new scheme is compatible with the popular IEEE 802.11 MAC protocol and involves adding very simple queue management and bookkeeping work mechanisms. Simulation experiments show that the new scheme can alleviate the fairness problems existing in applications running on either UDP or TCP with almost no degradation in throughput. More importantly, it is also shown that without explicit information exchange among nodes, the fairness problem cannot be solved conclusively.