| As a new kind of wireless network, WMN(Wireless Mesh Network) can improve the wireless network coverage range, centralized structure adaptability, optimal routing path acquisition and other issues, it has been integrated into the various physical layer standard, and has extensive application. As one of the key technologies in wireless network, routing technology is a research hotspot at home and abroad for WMN. In view of existing problem of HWMP in IEEE 802.11 s standard about bottleneck and congestion in WMN, in order to improve the throughput, reduce delay and packet loss rate, a new routing protocol of PMTRP(Proactive Multi-Tree Routing Protocol) which supports multi-gateway multi-path routing is proposed in this paper. By setting up proactive multi-tree and using AALM(Accumulated Airtime Link Metric) as the routing metric, PMTRP can transmit data in multi-gateway and do route selection in the process of data transmission. PMTRP can effectively balance network load, avoid the generation of network bottleneck, and reduce the impact of local node or local link failure on network performance, it is suitable for large-scale wireless mesh network deployment.To validate the performance of PMTRP, we select data packet delivery fraction, throughput and average delay as evaluation criteria, achieve the relevant modules of PMTRP in the NS-3 simulation software and compare with other routing protocols. Through making a comparative trial between PMTRP and the HWMP in mesh module in NS-3, it can be found that PMTRP has better performance in the multi-path routing path, and with the increase of network size, this advantage is more obvious. Comparison results of PMTRP and HWMP, multi gateway multi path routing protocol MGMP show that in the WMN which allows multi gateway selection, the performance of the three evaluation criteria of PMTRP is better than that of HWMP; although the local path is slightly inadequate, but in the average of the whole network, PMTRP has better multi-gateway performance than MGMP. The simulation results show that the PMTRP can effectively improve the network robustness and ensure the quality of network in large scale wireless Mesh networks. |
