Research Of Key Management Scheme Based On Matrix Combined Public Key Algorithm In Ad Hoc Networks

As a wireless network with no fixed communication infrastructure, Ad Hoc Networks have broad application prospects, especially in the military field. However, because of its inherent characteristics, Ad Hoc Networks faces more security threats and is easier to suffer enemy's attacks than other communication networks. In order to ensure secure application of Ad Hoc Networks, key management schemes are necessary.The aim of this dissertation is to develop an appropriate key management scheme based on Double Matrix CPK for the Ad Hoc Networks. The main contributions of the dissertation are summarized as follows:Firstly, CPK and Double Matrix CPK which can avoid the collusion attack are analyzed. Then, in order to increase system's usability, a two-layer distributed key management structure based on Double Matrix CPK and the threshold secret sharing scheme is proposed and analyzed. Secondly, keeping in mind of the characteristics of Ad Hoc Networks, the dissertation presents a set of schemes for cluster's basic and assistant private matrix shares and private key distribution. basic and assistant private matrix shares used in first-layer cluster are distributed with centralized and distributed way for the service nodes. basic and assistant private matrix shares used in second -layer cluster are distributed with distributed and self-organized way for all nodes.The private key generating scheme based on Double Matrix CPK and threshold technic is proved to be secure.Thirdly ,this dissertation deeply analyze the problems of node's private key updating. considering the attacks from mobile adversary, the entrance of new service nodes, significant changes of nodes'amount, basic and assistant private key shares updating schemes are designed respectively. malicious nodes are ascertained based on accused matrix. In order to avoid the effect of reliability enforced by malicious nodes on legal nodes, a malicious node ID revocation scheme based on weight and status is proposed.the system's efficiency is increased and the security of Ad Hoc Network is improved.Finally, a key management prototype system is designed based on the proposed key management scheme, and its principal modules are implemented. At last, the efficiency of the system is tested and analyzed.