Against mobile attacks in Mobile Ad-hoc Networks

Many recent security schemes for ad-hoc networks use identity-based cryptography and threshold cryptography. These schemes are subject to mobile attacks. The existing solution is secret refreshing. We notice some loopholes in this solution, and propose an improved scheme to address them. By dividing the master key of identity-based cryptography into static part and dynamic part, the scheme is more resistant to mobile attacks and some others, such as Sybil attacks. While remaining the key escrow free feature, the scheme can dramatically reduce secret refreshing overhead. Threshold cryptosystems using this scheme are thus more survivable and scalable.