Enhanced Security Using Cluster Based Certificate Management and ECC-CRT Key Agreement Schemes in Mobile Ad hoc Networks

With the increasing demand of wireless networks, in particular Mobile Ad hoc Networks (MANET), security over such networks has become one of the major issues concerned extensively. The security solutions proposed by various researchers failed in considering mobility aware node to node communication in the infrastructure-less ad hoc networks. Besides, the certificates as well as key management and verification complexities associated in MANET with a Public Key Infrastructure (PKI) framework are significantly large. This paper addresses the issue of certificate assignment and key management of secure group communications over MANET. We propose a novel certificate assignment strategy in order to significantly reduce the complexity of managing the PKI framework. The strategy involves partitioning the entire network into a number of cluster regions, and the assignment of region-specific certificates to a node resident in a cluster. We further proposed a secure key agreement scheme based on Elliptic Curve Cryptosystems (ECC) and the Chinese remainder theorem (CRT) to eliminate the security flaws and provide better security requirements. The proposed ECC-CRT key agreement scheme resists the know security attacks and provides authenticated group communication with less complexities and computational cost. The performances of proposed schemes are evaluated by simulation analysis and when compared with existing schemes, our schemes have the following advantages. (1) Simple to execute the certificate assignment and key agreement phases. (2) Easy to address dynamic rekeying when a node is added into or evicted from a cluster. (3) Efficient secret key updating scheme. (4) Secure against some potential security attacks. (5) Constant storage requirement for public and secret parameters.