Study And Improvements On Location-based Routing Protocols In Wireless Mesh Networks

Routing in wireless mesh networks has been challenging, because till now we haven't found a well-adjusted solution in distributed dynamic network environment. In recent years, location-aided routing protocol in wireless mesh networks has become hotspot, meanwhile, the location-based routing provides opportunity for wireless network to obtain better performance. Among which, GPSR(Greedy Perimeter Stateless Routing) was a representative protocol. With the method of greedy forward, GPSR can only use the local information of network topology to select the next hop which maxims the forwarding distance; When the data packet is forwarded to a node where the greedy mode is no longer available, GPSR algorithm will adopt the"right hand rule"to select the next hop, in addition, it takes advantage of periphery forward for void detour. Based on the analysis of GPSR, a lot of improved protocols have been proposed.This paper first describes the main points of routing protocol design in wireless mesh networks, analyzes the shortcomings of some existing location-based routings'improving algorithms. Then, under the guidance of cross-layer design and the opportunity routing theory, we propose a new routing protocol IAPR(Interference Aware Progress Routing). The new algorithm is aimed to improve the performance of location-based routing protocol in respects of greedy forwarding and void detour. In greedy forwarding mode, we use a new routing metric which can judge the forwarding distance, link quality and the difficulty of channel access during the process of the next hop node selection. Makes sure the advantageous link can be chosen. When the packet forwarding comes into a local minimum, IAPR uses an opportunistic forwarding method based on competitive advantage. Unlike normal opportunity forwarding methods, we consider not only the location of node and link quality, the competitive factors are added to the new algorithm, thus the possibility of packet turning the void detour mode back to the greedy mode can be realized. As a result, a helpful neighbor node along the void edge will have priority to send back an acknowledgment.Finally, simulation experiments with NS2 and comparison with existing improved algorithms of GPSR are done. The results indicate the IAPR can improve network resource utilization, reduce congestion packet loss, and ultimately improve the average throughput of the wireless mesh network.