The Research On The Performance Of The IEEE 802.11s Path Selection Protocol

Currently, Wireless mesh networks have received increased attention over the last year. Since 802.11 TGs founded on July, 2004, three WGs of the IEEE project 802 have work on WMN.The main characteristic of WMN is the communication between nodes over multiple wireless hops on a mesh network graph. Efficient routing protocols provide paths through the wireless mesh and react to dynamic changes in the topology, so that mesh nodes can communicate with each other even if they are not in direct wireless range. Intermediate nodes on the path will forward the packets to the destination. MANET is based on the same principle– wireless multi-hop communication and mobility of the nodes. So, the routing protocols developed for MANET are often applied to WMN.The dissertation firstly study and analyze the traditional routing protocols of MANET and default protocols of 802.11s, and then makes a research of the traditional routing metrics with routing protocols. We proposed an integrated scheme of path metric based on link type, and make an extension based on multi-rate to the traditional ETX, ETT, and WCETT. Meanwhile, we introduce an effective and accurate link measurement called EAR for getting the accurate link metric to improve the performance of path selection. The link type metric support to find the more stable path and the modified WCETT based on multi-rate support the compatibility to multi-rate and to traditional 802 networks. The result of simulation reveals that these measures improve the network performance better than what the default metric Airtime and path metric computation scheme of 802.11s can do.