Performance Analysis of Wireless MAC Protocols Using a Search Based Framework

Previously, we have developed a framework to perform systematic analysis of CSMA/CA based wireless MAC protocols. The framework first identifies protocol states that meet our study objective of minimizing a given performance metric. It then applies search techniques and heuristics to construct sequences of protocol events in a given topology that satisfy our objective. In this paper, we demonstrate that our framework can easily be extended to evaluate performance of new protocols by evaluating two completely different variants, namely MAC protocols for (i) quality of service (QoS), and (ii) power control. In each case, we identify previously unknown problems with the protocol. In particular, we generate scenarios where throughput of a lower priority class can be as high as 5 times compared to the throughput of a higher priority class, thus contradicting the basic notion of QoS. Traditional performance evaluation approaches typically evaluate average performance but do not capture the worst cases, nor do they expose the protocol breaking points. Thus this paper demonstrates the usefulness of a systematic approach in evaluating the protocol breaking points.