Multi-PKG ID-Based Signcryption with Anonymity and Traceability for Ad Hoc Networks

Delivering messages anonymously in ad hoc network is very important because of the special characteristics. Meantime, a trusted third party can trace the message sender by using some secret keys in case of dispute. Recently, a multi-PKG ID-based signcryption scheme for ad hoc networks is proposed, which is semantic security and existential unforgeability in random oracle model. But it is not anonymous when delivering message. In this paper we analysis this scheme, and propose an improved multi-PKG ID-based signcryption by using bilinear pairing. Comparing with the original scheme, we retain all the advantages, and do not add any communication overhead. Our scheme has two new features, anonymity and traceability, by only one more bilinear pairing computation. The new scheme is also proved security. And it can be used for the area of e-cash and e-vote.