Service Sensitive and Fuzzy Based Queue Control Method and Its Performance Evaluation

With the continuously increasing applications of multimedia communications in Ad hoc network, network is experiencing a serious congestion problem. This paper proposes a fuzzy based queue control method (FQCM for short) which applies fuzzy set theory to queue control to avoid congestion or to recover from congestion state rapidly. The proposed queue control method adjusts data loss ratio according to the output of fuzzy logic system whose input variables are dynamic global and local buffer occupancy. Service type and its QOS requirement are considered carefully when we design our fuzzy logical system. So our queue control method is service sensitive. We evaluate the performance of FQCM over a wide range of traffic conditions. The simulation results show that the performance of FQCM is superior to the conventional queuing method in terms of delay, jitter of delay and packet loss ratio. The FQCM is sensitive and effective to different types of service and different network scales.