Establishment of stable certificate chains for authentication in mobile ad hoc networks

MANETs are an ideal technology to deploy spontaneous wireless infrastructure-less networks, either for military or civilian applications. The absence of centralized administration and infrastructure-less nature gives rise to authentication and key management problems in the MANETs. Recently, several approaches have been proposed for the authentication mechanisms. Among of them, certificate chain based authentication mechanism better suits the MANET environment due to its self-organization nature. However, an unstable topology and link failure which is quite common in MANET pose a greater challenge to the certificate chain mechanism. To overcome this, we propose a stable certificate chain based authentication mechanism for MANET. Here, the route selection algorithm incorporates the Link Expiry Time which helps in selecting links for authentication and data communication. This enhances the stability of the certificate chain which in turn provides enhanced security. It has been found that the proposed scheme decreases the number of path changes and the time taken for authentication. Simulations done in NS2 (Network Simulator tool) gives better performance in terms of standardized parameters such as Routing Overhead, Packet Delivery Ratio, End-to-End delay and Time Taken for Authentication in comparison with the existing certificate chain mechanism.