Based On Wireless Mesh Network Communication Protocol

In recent years, in case of the large amount of the occurrence of the multimedia traffic especially the real time video traffic in future, the legacy IEEE 802.11e access control protocol can no longer meet the traffic QoS requirement or the fairness of transmission in Wireless Mesh Network. MAC protocol is the main factor to determine the efficiency of the shared wireless channel. In order to solve this problem, it's important to propose some fairness schemes based on IEEE 802.11 e.This thesis mainly focuses on how to provide the QoS in wireless mesh networks, where the topology is dynamic and the bandwidth is constrained.Towards providing multimedia traffic as well as differentiating local and forward traffic, the work investigates the multi-channel MAC for wireless mesh networks based on IEEE 802.11e, and some original schemes are proposed. This paper briefly introduces how 802.11e EDCA works and proposes an improved algorithm named L-EDCA. L-EDCA is a modified scheme based on EDCA. L-EDCA provides a new definition in which user level traffic mapps to the new priority, meanwhile it has a "differentiating local and forward traffic" function. Through a number of network simulations, we find that L-EDCA has better performance than EDCA. We propose a fairy dynamic queue scheduling scheme and a trac-aware scheme fairy. A number of network simulations, show that network contention overhead is reduced and the network throughput is increased. The access chance of lower priority traffic is enhanced significantly, and the network transmission fairness is satisfied with this improved scheme.