Existing Wireless Sensor Network Random Key Pre-distribution Scheme, Analysis And Improvement

This paper analyzes the q-composite scheme, which is the better one of random key pre-distribution schemes, and then designs a new scheme with high security performance and high feasibility. The new scheme is based on the q-composite scheme. The bivariate polynomial is used, and the key pool in the q-composite scheme is changed into bivariate polynomial pool, and the key ring stored in each node is changed into bivariate polynomial ring. Then the q-composite scheme based on bivariate polynomial is designed. This new scheme has not only the strongpoint of the traditional key distribution scheme, but also the high security performance of q-composite scheme in condition of small number of captured nodes. This scheme consumedly increases the limit of captured nodes which is low in the q-composite scheme and increases the nodes number that the network can support. The scheme is suitable for the WSN that higher security performance and a larger number of nodes are needed.The same weakness of the basic random key pre-distribution scheme, the q-composite scheme, and the new scheme designed in this paper is that it contains a lot of information related with other nodes. When a node is captured, the information in the node will reveal the secret of other nodes. This will compromise the other nodes and their security communication. This is the common weakness of random key pre-distribution scheme and it is caused by its elements of pre-distribution. How to solve this problem is the aim of our research. In this paper, the method of key renewal is used. After the security communication is established, the key renewal is performed. The new key will have no relationship with another one. So, enemies can't gain the secrets of other security communications though the captured nodes.By this method, an integrated q-composite scheme based on bivariate polynomial is designed.