A novel multiple access protocol for multihop mobile ad hoc networks

Based on the concept of contention reservation for polling transmission and collision prevention strategy for collision resolution, a fair on-demand access (FODA) protocol for supporting node mobility and multihop architecture in mobile ad hoc networks is proposed. In the protocol, a distributed clustering architecture and an idea of reserving channel resources to get polling service are adopted, so that the hidden terminal (HT) and exposed terminal (ET) problems existed in traffic transmission due to multihop architecture and wireless transmission can be eliminated effectively. In addition, a fair collision prevention (FCP) algorithm is proposed to greatly eliminate unfair phenomena existed in contention access of newly active nodes and completely resolve access collisions. Finally, the performance comparison of the FODA protocol with CSMA/CA in IEEE 802.11 and polling protocols by OPNET simulation are presented. Simulation results show that the proposed protocol has better multiple access performance than CSMA/CA and polling protocols.