Ad Hoc Network Research, Self-organizing Key Management Scheme

Mobile Ad Hoc network is multi-hop temporary automated system which consists of a group of mobile terminal nodes.In Mobile Ad hoc network,owing to many new characteristics,the security situation is more rigorous than that in traditional network. Cryptography is one of main security means in wireless communication environment. Key management(KM),which is the core of the cryptosystem,is also a very weak link of Mobile Ad hoc network security.This thesis proposes an optimized scheme of self-organized key management to the main problem in key management of Mobile Ad hoc network which is based on the relational research about self-organized key management scheme in recent years.The main contributions of this thesis include:(1)It proposes a new local certificate repository algorithm for self-organized key management scheme in Mobile Ad hoc network.In this algorithm,the node and its neighbors promulgate the certificates each other to create their own in-degree and out-degree certificate repositories.Based on the ant colony algorithm,the certificate path is searched originally from the node which certificated times is the max between the start node and the end node.The algorithm improves the efficiency of search path and assures finding the certificate path,and besides,it saves the storage space of local certificate repository.Simulated results showed that it was an optimized local certificate repository algorithm.(2)Based on the "Trust Relationship" of PGP,a secure algorithm for affiliating new nodes of self-organized key management scheme was proposed by using the ^(t,n) threshold secret sharing scheme.By the multi-authentication for new nodes and the judgment of the identification in consistency and uniqueness,the security of the new nodes in Ad hoc network was ensured and the self-organized key management scheme was improved.Simulated results showed that the successful rate of authentication was ensured while the new nodes were authenticated security,thus improving the security of the networkAt last,the thesis gives a conclusion and presents the research direction.