A Trust Based Threshold Revocation Scheme for MANETs

Security is very important for the reliable operation of mobile Ad Hoc networks (MANETs). One of the critical security issues in MANETs is the revocation of misbehaving nodes. In this paper, we propose a trust based threshold cryptography revocation scheme for MANETs. In our proposed scheme, the master private key is split into n pieces according to a random polynomial. Each node in the proposed scheme is configured with a share sk_i of the CA private key SK, the node´s public key pk_i, and the CA public key PK before joining the network. Meanwhile, the master private key could be recovered by combining any threshold t pieces based on Lagrange interpolation. Consequently, the proposed scheme improves the safety levels in MANETs. The proposed hop-by-hop certificate revocation scheme is based on both threshold cryptography and transitive trust between mobile nodes. Because of the decentralized nature of our proposed scheme, it enables a group of legitimate nodes to perform fast revocation of a nearby misbehaving node. The proposed scheme is highly robust in the mobility environment of MANETs. The advantages of the proposed scheme are justified through extensive simulations.