Jamming-based medium access control with dynamic priority adjustment in wireless ad-hoc networks

Abstract

The paper presents a jamming-based MAC with dynamic priority adjustment (JMDPA) for multimedia services in wireless ad hoc networks. The proposed scheme differentiates multimedia traffic into classes with different priority levels. A mobile node is prioritised in frame transmissions by issuing a precalculated length of jamming noise: the one with the longest jamming length can win the frame transmission. The winner immediately broadcasts its current priority level (local priority) to update the global priorities of all the neighbouring nodes. The global priority is used as a contention baseline, which prevents any node with a local priority lower than the baseline from participating in the next contention. One of the innovative designs in the proposed scheme is right, in that the priority of a mobile node can be dynamically adjusted according to network conditions so that any possible starvation of low-priority traffic or any ineffective contention of high-priority traffic can be avoided. A multidimensional Markov model, together with the scalability analysis, is introduced to evaluate the performance of the proposed JMDPA. The analytical results provide very useful guidelines to tune the QoS parameters for supporting prioritised multimedia traffic in wireless ad hoc networks.