Key Management in Web of Trust for Mobile Ad Hoc Networks

A mobile ad hoc network MANET is a collection of wireless mobile nodes dynamically forming a temporary network without the use of any existing network infrastructure or centralized administration. Trust establishment and management are essential for any security framework of MANETs. Providing key management through accessing trusted authorities or centralized servers is infeasible for MANETs due to the absence of any infrastructure, frequent mobility, and wireless link instability. In this paper we propose a self-organized, hop-by-hop public key management for MANETs based on transitive trust between mobile nodes. Each node creates its public key and the corresponding private key locally by the node itself, issuing certificates to neighboring nodes, and holding certificates in its local certificates repository. Authentication of public keys is performed by using both direct and recommendation trust. The proposed scheme has low communication cost and the simulation results show that the scheme is highly robust in the mobility environment of MANETs.