Research Of Multi-channel MAC Protocol And Routing Protocol In Wireless Mesh Networks

In recent years, researches on WMN have been very popular around the word. Among them, multi-channel technology is a key factor influencing performance optimization of WMN, so the researches about multi-channel technology have become one of the hot spots in wireless mesh network. Multi-channel MAC protocols and multi-channel routing protocols are two important aspects in the research of multi-channel technology. Multi-channel MAC protocols focus on the allocation and management of multi-channel resources, while multi-channel routing protocols focus on how to look for the path of channel diversification and high-throughput.Firstly, based on the analysis of the existing MAC protocols of WMN, a multi-channel MAC protocol with two-interface based on the IEEE 802.11 standard hardware is proposed, which is named DIM protocol. The greatest feature of DIM protocol is that it can make full use of channel resources provided by the 802.11 standard in the lower hardware configuration. The DIM protocol divides two interfaces of node into fixed interface and switchable interface, the fixed interface modulates channel statically, while, According to the situation of communication, the switchable interface applies channel switch to modulate channel dynamically. By building a model of channel conflict, the DIM protocol implements channel selection algorithm to select channel for the fixed interface. Through the establishment of channel queues and channel switch principles, the DIM protocol implements effective management to the switchable interface.Secondly, based on the analysis of the existing routing protocols of WMN, a new multi-channel routing protocol named MCR protocol is also put forward. The MCR protocol is on the basis of DSR protocol which is used in the Ad Hoc network, a new routing criterion called WCETT-LB is applied in MCR. WCETT-LB does some improvements on WCETT. Compared with WCETT, WCETT-LB considers the internal channel distribution of path, so it can assess channel conflict of path accurately, besides, a load criterion, L(P), which is used to reduce the network congestion, is incorporated into WCETT-LB. Furthermore, to consider the characteristics of DIM protocol, MCR deals with channel switch for routing performance, so the two protocols can be used well together.