Research and Implementation on Mac Protocol and Routing Protocol in Wireless Mesh Networks

Wireless Mesh Network is a new type of broadband wireless access system.WMN is a combination of WLAN and mobile Ad Hoc network with thecharacteristics of reliability, self-organization and self-healing. For the instability ofWireless Mesh network topology and wireless channel, the allocation of channelresources and management, as well as the packet addressing and forwarding both playa very important role for performance optimization of Wireless Mesh Network. Thusthe design of Mesh protocol on MAC layer and routing protocol becomes one of thekey factors for its performance.In this paper, besides introducing wireless Mesh networks, structure, features andkey techniques, several existing routing and MAC protocols were also studied andanalyzed. At the same time, to meet the practical application needs, according to thedifferent ways of resource allocation, this paper puts forward three differentmulti-channel channel MAC protocol design scheme. To reduce the consumption forresource consultation and the system time delay, taking MAC protocol based oncentralized static resource allocation as example to give a specific time slot allocationand channel distribution plan; Considering QoS for Layer3 routing is fragile to thechange of network apology, a new model based on Layer2 routing is proposed toavoid such defects and limitations. The packet forwarding, setup and maintenance ofthe connectivity are accomplished in Mac Layer. NS2 Simulation tests show that,layer2 packet forwarding is much more efficient, and also reduced the routingoverhead as well as the p2p delay.