Location-based Key Management Scheme For Wireless Sensor Networks

Wireless sensor networks is a rising technology, and have wider application foreground, it will play more and more important role at many facets of people's life in future. But it is a challenging problem to improve sensor nodes' connectivity in sensor networks with security. Due to the special characters of sensor nodes, many traditional key management schemes are unsuitable for wireless sensor networks, so it's important to research the management schemes that suit the wireless sensor networks.Firstly, the current hot and difficult problems are introduced in this thesis. For security technology, the key management and authentication schemes of WSN are summarized and analyzed. The current key management schemes are analyzed from the angle of random key management and determine key management, also the relation and comparison are showed for random key management schemes. In the authentication part the current schemes are summarized from the angle of symmetry and asymmetry key organization.Then, in this thesis, a new location-based key pre-distribution scheme is presented, i.e. LBRKS, which makes use of deployment knowledge of node in the network. Before deployment, the base station maps key pool into the target area uniformly. For each node, there is an expected location and a deployment location, and the deployment location obeys uniform distribution. Each node picks keys based on its expected location with a certain probability. The probability of neighbor nodes sharing direct keys for different picking key probability and node localization ability is studied. Also, the relation of compromised probability and the number of compromised nodes is studied. The analysis indicates that for a given node localization ability, when the area increases, the compromised probability of the nodes decreases. It's suitable for large scale networks. Also, compared with CPKS, the probability of neighbor nodes sharing keys is further improved.Finally, on the basis of LBRKS, an improved scheme is proposed, i.e. LBAS. The scheme shows the nodes' authentication procedure, which has some merits as follows: strong compromised probability, resisting of DoS attacks and node copy attacks.