Research On Key Techniques Of Secure Routing In Wireless Sensor Networks

In recent years, wireless sensor networks have been widely used in so many fields of national economy and daily life, with their unique characteristics and important application value. Routing protocol is the basis of sensing data transmition and aggregation in wireless sensor networks. Because of the unique characteristics and complexity in application environments, ensuring the security of routing protocols has become an important supporting technique in wireless sensor networks, which will affect the quality of monitoring the surrounding physical world directly. The limited computing power, limited storage capacity and limited communication capability have restricted the development of secure routing techniques of wireless sensor networks. The main design goals of this dissertation are ensuring the security of routing protocols, and at the same time, reducing and balancing the energy consumption of the sensor nodes, and prolonging the lifetime of wireless sensor networks. This dissertation makes a detailed analysis and in-depth study on the secure routing problem in wireless sensor networks. The major contributions of the dissertation are summarized as follows.(1) The problem of secure location discovery for wireless sensor networks with attack tolerance is investigated, and a secure consistency-based majority-colluding attack resistance secure location discovery algorithm is proposed. Aiming at the poor robustness against attacks and the low efficiency of the existing location discovery algorithms, an accelerated consistency-based strategy is proposed based on the voting-based location estimation algorithm, and all the location references from beacon nodes are ordered according to their consistency so as to accelerate the convergence rate of the target region. In order to resist majority-colluding attacks by colluding nodes, the location information of the non-beacon nodes which have been located securely is used in the location discovery process as the approximate location reference, and a secure consistency-based majority-colluding attack resistance location estimation algorithm is proposed further. Extensive simulation experiment results demonstrate that the proposed algorithm can resist majority-colluding attack effectively, detect and filter out the malicious nodes successfully, and enhance the accuracy of the location estimation results. (2) The problem of source node location privacy protection in wireless sensor networks is investigated, and a fan-shaped region based source node location privacy protection routing algorithm is proposed. Aiming at the balancing problem of the source node location privacy protection and routing algorithm efficiency, a fan-shaped region based source node location privacy protection routing algorithm is proposed. The proposed algorithm uses the central angle size of the fan-shaped region to control the routing path direction, so as to ensure that the packets can be forwarded towards the direction of the sink node. In order to protect the location privacy of the source node, a mechanism is adopted which randomly selects a fan-shaped sub-region as the optional area of the next hop. Meanwhile, the distance between the selected node and the source node, and the distance between the selected node and the sink node are all given consideration while selecting the relay node, to ensure that while enhancing the source node location privacy, the energy consumption of the network can be reduced effectively and the execution efficiency of the routing algorithm can be improved. A series of simulation experiment results show that the algorithm can enhance the source node location privacy effectively, and has relatively better performance in energy consumption, delay and data delivery rate, etc.(3) The problem of game theory based secure routing for wireless sensor networks is investigated, and a cooperative strategy based dynamic game routing algorithm is proposed. Aiming at the unbalanced energy consumption problem and the low efficiency of the routing algorithm with the traditional game theory based WSN secure routing mechanism, a cooperative strategy based dynamic game routing algorithm is proposed. An incentive mechanism is proposed, the selfish nodes are encouraged to forward packets, and the non-cooperative nodes are punished. In the process of route selection, each sending nodes and receiving nodes can make optimal decision according to their payoff functions, so as to ensure that the packets can be transmitted to the sink node along a safe, high efficiency, and energy saving path. Simulation experiment results show that the above mechanism can impel rational selfish node actively participate in routing cooperation, and can effectively increase the throughput and prolong the network lifetime.(4) The problem of reputation-based secure routing for wireless sensor networks is investigated, and a reputation-based secure routing algorithm is proposed to stimulate node cooperation. The traditional reputation-based routing models have poor fault tolerance against the interference from environmental and other factors. Aiming at this problem, a reputation-based secure routing algorithm is proposed to simulate cooperation. In this algorithm, each node observes the data packet forwarding behaviors of its neigbor nodes, and exchanges the observed information with its neighbor nodes. Then, the sensor node calculates the reputation of the node being observed according to the direct and indirect observations, and the difference between its own reputation and the reputation of the node being observed is used as a punishment to the node being observed. This algorithm can reduce the impact of environmental interference on the reputation of a sensor node, and can also stimulate the sensor node to be cooperative actively in order to get better reputation, so as to avoid being punished. Simulation experiment results show that the algorithm has strong fault tolerance ability against packet collisions and environmental interference, and can also reduce the impact on the performance of the wireless sensor networks from non-cooperative nodes.