Two Level Hybrid key Scheme for Efficient Key Distribution in Mobile Ad-Hoc Networks

Military command and control require that information be communicated to the appropriate groups and only with the utmost security. At the same time the environment envisioned by the Objective Force is mobile ad-hoc and consists of a large number of heterogeneous nodes deployed in a hostile field of limited bandwidth and unreliable channels. The nodes of the network may present severe bandwidth, energy, capacity and processing constraints (vary from Satellites, PDAs, laptops, to GPS devices, cellphones and pagers). In this work we develop a secure, robust and scalable key management scheme for multicast communications. This service is very important in determining the security and efficiency of the network. It consists of key generation, entity authentication and key distribution. We assume that the nodes are already authenticated and focus on studying and developing key distribution techniques with the aim to achieve scalability and high performance of our key distribution framework without sacrificing the security level of the network. For that we need to reduce the total storage, communication and computation cost of the nodes, resulting from the key distribution protocol we apply to our network. The new key distribution framework we designed is a hierarchical, two-level hybrid key management scheme.