An Energy Efficient Key Management and Authentication Scheme for Multicasting in Ad Hoc Networks

In Mobile Ad hoc Networks (MANETs) multicasting, when an attacker inserts spurious packets into the network any time, its neighbors can drop these packets when proper authentication is performed. Hence, efficient authentication with key management is required for multicasting in MANET. Also multicast key management in ad hoc networks involves energy expenditure in key distribution and rekeying. In this paper, we propose a trust authority based key management and authentication technique for multicasting in ad hoc networks. Initially we construct an energy efficient topology aware key tree which mainly aims to reduce the re-keying load by pre-processing the joining members during the idle re-keying interval. Key management is processed based upon Diffie-Hellman key pair and RSA secret public key pair. A trust authority establishes public key certificates for each group member by signing the public key with its secret key. From the simulation results we show that this key management guarantees key authentication, enhances fault-tolerance and protects the tree from impersonation attacks.