Distributed CA-based PKI for Mobile Ad Hoc Networks Using Elliptic Curve Cryptography

The implementation of a standard PKI in a mobile ad hoc network (MANET) is not practical for several reasons: (1) lack of a fixed infrastructure; (2) a centralized certification authority (CA) represents a single point of failure in the network; (3) the relative locations and logical assignments of nodes vary in time; (4) nodes often have limited transmission and computational power, storage, and battery life. We propose a practical distributed CA-based PKI scheme for MANETs based on Elliptic Curve Cryptography (ECC) that overcomes these challenges. In this scheme, a relatively small number of mobile CA servers provide distributed service for the mobile nodes. The key elements of our approach include the use of threshold cryptography, cluster-based key management with mobile CA servers, and ECC. We show that the proposed scheme is resistant to a wide range of security attacks and can scale easily to networks of large size.