Achieving Delay Guarantees in Ad Hoc Networks Using Distributed Contention Window Adaptation

In this paper, we propose a new protocol, named DDA (Distributed Delay Allocation), which provides average delay guarantees to real-time multimedia applications in wireless ad hoc networks. By adapting the contention window sizes of IEEE 802.11, DDA schedules packets of flows according to their individual delay requirements. The novelty of DDA is that it imposes no control message overhead on the network and does not depend on explicit knowledge of channel capacity. We rigorously prove the convergence property of DDA and show that it always converges to a contention window allocation that satisfies all competing realtime flows’ delay requirements, if the requirements of all realtime flows do not exceed the capacity of the network.