A Cross Layer Multipath Routing Protocol Based On AODV For Wireless Mesh Networks

With the further development of mobile wireless communication, there will be more and more demand of wireless voice and data services, especially high-data-rate Internet access. Data rate of long-distance wireless communication is very limited because of attenuation. Wireless multi-hop communication can provide much bigger bandwidth and Internet access through multi-hop wireless routers. Therefore, wireless mesh networks become an important networking technology. Wireless mesh networks (WMNs) present a promising solution by extending network coverage based on the mixture of wireless technologies through multi-hop communications. WMNs support ad hoc networking with the capability of self-forming, self-healing and self-organization. Mesh routers have minimal mobility and perform dedicated routing, which significantly decreases the load of mesh clients and other end nodes. Furthermore, mesh routers have no power-consumption constraints and perform more complicate functions.In this thesis, we propose a cross layer multipath routing protocol, which is based on AODV.In our proposed routing protocol, we improve the AODV to multi-path routing by the address of the first hop node to ensure that the independent routing trees by the root of each of the neighbor node of the source node are established as more as possible between the source node and destination node. Meanwhile, We combine the standards of cross-layer routing mentioned in the literature[1] with the improved AODV of multi-path.In the literature, two congestion-aware cross layer routing metrics are introduced:buffer occupancy ratio (BOR) and successful frame delivery rate (SFDR). BOR is used to measure congestion degree at a node.The larger BOR, the more congested the node is.In a partial congested area of wireless networks, there are so many traffic flows that the limited wireless resource is not enough for packet forwarding, resulting in packet loss due to heavy channel contention.SFDR considers the congestion of links and area congestion degree. These metrics are used to find multiple less congested routes to improve the throughput and stability of networks.The simulation study has shown that the proposed routing scheme achieves significant throughput enhancement and full use of network resource through much more reliable packet delivery.