The MAC Mechanism with QoS Provision Based on Stream-Maintenance in Ad Hoc Networks

Because the signal of different nodes interferes with each other, the collision happens frequently in ad hoc networks. If only adopting contention-based MAC protocol, it is hard to guarantee quality of service (QoS) of multi-media services such as voice and video in ad hoc network. A series of periodical realtime service packages from the same source node can be regarded as a real-time data stream. By adopting the resource reserve mechanism to improve the IEEE 802.11 DCF, a new type of MAC mechanism including MAC-FM and MAC-FM (E) is brought forward in this paper. MAC-FM and MAC-FM (E) reserve dynamically the time slots for the real-time data stream in distributed mode to avoid the collision of real-time service packages. In addition, the networks performance including delay and throughput is analyzed in theory and validated via simulation. The result indicates that MAC-FM and MAC-FM (E) can decrease the delay greatly and increase the throughput of ad hoc networks