Research And Security Improvement Of LEACH Protocol In Wireless Sensor Networks

Wireless sensor networks are composed of a large number of cheap micro sensor nodes deployed in the monitoring area, which forms a multi-hop and self-organized network system through wireless communication. At present, wireless sensor networks are widely used in industry, agriculture, commerce, military and other fields. Nowadays, the related technology of wireless sensor networks such as routing protocol, MAC protocol has been developing rapidly,while the research on security is gradually unfolded. With the increasingly severe situation of information security, the security of wireless sensor networks has become a hot research topic.Firstly, this paper introduces the concept and application of wireless sensor networks, and describes the security issues of wireless sensor networks. Then, this paper focuses on the LEACH routing protocol and its security issues. Due to the limited resources of sensor nodes,many mature network security technologies can not be used in wireless sensor networks. This paper proposes a low power comsuption and security improvement protocol based on LEACH in the premise of limited resources. The protocol has made the following improvements to the LEACH protocol:(1) In order to reduce energy consumption, it improves the cluster head election algorithm and the optimal cluster head selection strategy. In the cluster head election, the residual energy of the node, and the distance to the base station are very important reference factors.In addition,the selection of optimal cluster head needs to consider the cluster head signal strength, residual energy and the distance to the base station and other factors.(2) We construct a kind of key management system by using the symmetric key mechanism based on predistribution mechanism for LEACH protocol. To ensure the security of the whole system by periodically updating the main key of the network, the node keys and the cluster keys.In addition, the key management mechanism is integrated with the mechanism of message authentication, identity authentication and link authentication. The application of these lightweight security mechanisms for the LEACH protocol helps building a robust security defense system.(3) This paper proposes the cluster head monitoring mechanism for LEACH protocol, the cluster head monitoring mechanism select another cluster head for each cluster head asmonitoring node. Monitoring cluster head node will transmit data to the monitored object, and transmit the tracking data to the base station at the same time. So, the base station can detect whether there is a packet loss attack in the network by analysis and calculate the data form monitoring cluster head nodes.In this paper, we use NS2 to realize and simulate the improved protocol. After a lot of experiments, the improved protocol proposed in this paper is effective in defending against external attacks which are fired by illegal attackers. The improved protocol has a certain ability to detect attacks fired by the cluster heads which are captured by attacker, such as tampering,packet loss, and the like. In addition, the simulation results show that the proposed protocol which has used the low power design strategy can reduce the energy consumption increase raised by the introduction of security mechanism, and the energy consumption is basically close to the LEACH protocol.