Research On Multipath Routing Protocol And Its Security Mechanism In Wireless Mesh Networks

Wireless mesh networks (WMN) have emerged as a key technology for next-generation wireless networking. In WMNs, mesh routers self-organize to a mesh backbone to provide stable, fast wireless access to Internet for mesh Clients. The mesh topology and self-organization characteristics make routing protocol become a key technology for WMNs. Routes which selected by routing protocols would directly affect the performance of network. Multipath routing protocol is considered to effectively improve the performance of date transmission.Multipath routing protocols set multiple routes between source and destination as traditional routing protocols usually only selecting one. Those paths could be used simultaneously or alternately. Multipath routing protocols can improve the robustness of routing, provide load balancing and perform better bandwidth and delay of data transmission. In addition, data transmission scheme based multipath routing can effectively enhance the security. We will focus on multipath routing protocol and its security mechanism in WMNs.In this thesis we first introduce the research background of WMNs, emphatically introducing the properties and category of WMNs'routing protocols. The second chapter discusses the background and key problems of multipath routing. Then we introduce several kinds of classical multipath routing protocols. Existing multipath routing protocols usually ignore the inter-path interference which can seriously affect the performance of data transmission. In chapter 3, with deep analysis of this problem, we propose a novel routing metric IAMM (Interference-Aware Multipath Metric) based on the 802.11 MAC protocol model to quantify the inter-path interferences. Furthermore, an Interference-Aware Multipath Routing (IAMR) protocol is also proposed based on IAMM. Through a dual path selection method, IAMR takes into account not only the performance of each single path but also the inter-path interference between selected paths. The result of simulation shows that IAMR significantly improves the performance on transmission throughput, end-to-end transmission delay and the arrival rate of packets.The complexity of wireless environment and self-organization characteristics bring great challenges to security in WMNs. In chapter 4, we introduce the background of WMNs'security and discuss attacks and security mechanism in WMNs'routing protocol. Among these security mechanisms, multipath based message transmission scheme is considered to be an effective way to improve security of data transmission. The fifth chapter first introduces related secure message transmission schemes based multipath routing. Based on the deep analysis of existing research, we proposed an Enhanced Secure Message Transmission (ESMT) scheme. ESMT focuses on data confidentiality and availability. It uses a redundancy encoding technique to divide original messages into multiple pieces, and a one-way function associated with secret share to dynamicly computer session keys for each path. Each encoding piece is encrypted by a different key and then transmitted on a different node-disjointed path. Security analysis shows ESMT could guarantee data availability to a certain degree as well as effectively enhance data confidentiality.