Tree-Like Peer-to-Peer Symmetric Key Management in Mobile Ad Hoc Network

Cryptography has been the core of security framework in Mobile Ad hoc Network (MANET). Cryptographic mechanisms mandate key management for a secure peer-to-peer communication. In MANET, due to limited energy and processing capabilities of mobile nodes, symmetric key management has been an active research area among others. Several research have been made in symmetric key management, but the solutions there in are either computationally complex and have message overheads, or have routing overheads. Further, most of them are with some preloading schemes. They too lack in simplicity. In this paper we propose a symmetric key management scheme for secure peer-to-peer communication in MANET. In the proposed scheme, every designated mobile node constructs tree by randomly ordering the mobile node IDs in the topology. Tree at multiple designated mobile nodes contribute partial pairwise keys to appraise the symmetric key for a communicating pair. Distributed tree structure in the form of multiple tree makes it robust and scalable with minimized probability of compromise. The proposed scheme has simplicity in itself. It has neither any overheads nor any preloading scheme or predistribution of keys.