An efficient heterogeneous key management approach for secure multicast communications in ad hoc networks

In a mobile wireless ad hoc network, mobile nodes cooperate to form a network without using any infrastructure such as access points or base stations. Instead, the mobile nodes forward packets for each other, allowing communication among nodes outside wireless transmission range. As the use of wireless networks increases, security in this domain becomes a very real concern. One fundamental aspect of providing confidentiality and authentication is key distribution. While public-key encryption has provided these properties historically, ad hoc networks are resource constrained and benefit from symmetric key encryption. In this paper, we propose a new key management mechanism to support secure group multicast communications in ad hoc networks. The scheme proposes a dynamic construction of hierarchical clusters based on a novel density function adapted to frequent topology changes. The presented mechanism ensures a fast and efficient key management with respect to the sequential 1 to n multicast service.