Research On Trust Management In Wireless Sensor Network Of Hydrological Monitoring

Hydrological monitoring is the key technology to realize water conservancyinformation, and it plays an important role in water conservancy project safety, floodcontrol, predict and early warning. Since the21st century, the high development ofwireless sensor network(WSN) has provide the hydrological monitoring with effectiveway.WSN has not only realized automatic water information collection, transmission,storage and processing, but also improved the accuracy and real-time of water qualitymonitoring, early warning of flood and drought disaster, and reduced economic losses andsocial casualties.But in the hydrological monitoring, WSN deploys in the open environment, traditionalsecurity mechanisms based on cryptology are difficult to prevent hydrological data loss,tampering from environmental changes, node capture. Trust management is an effectivecomplement to the security mechanisms above, can effectively protect WSN from thesesecurity hidden danger, and has been widely studied both at home and abroad. Accordingto the special application environment of hydrological monitoring, we proposed a suitabletrust management system for the WSN of hydrological monitoring, nodes in the WSNmonitor their neighbor nodes’ communication actions of normal cooperation, packet loss,tampering by watchdog mechanism as a basis of neighbor nodes’ credibility evaluation,then according to trust value calculation, nodes describe the believable degree of neighbornodes by specific numerical(trust values).Trust management system based on the nodes’trust values can identify the malicious nodes from normal nodes and maintain the safety ofhydrological data. In addition, communication link broken caused by the wireless signalfluctuation of sensors in hydrologic monitoring resulting from environmental impact willlead to the problem that sensitive nodes cannot attend network cooperation due to the lowtrust value because of continuous packet loss. An identification and inspection mechanismof sensitive nodes is put forward to avoid such situation, it allows sensitive nodes join thenetwork again after observing the restoration of broken communication link, and as a result,the utilization rate of the WSN resource will be improved.Finally, TM-AODV protocol is proposed by applying trust management system toAODV protocol, and it can prevent malicious nodes from data transfer process by the trustvalue comparison. Through NS2simulation experiment, TM-AODV protocol is verified tohave more advantage than the original AODV protocol in packet loss rate and throughput.