Abstract: An aggregate signature scheme is a digital signature that given n signatures on n distinct messages from n distinct users, it is possible to aggregate all these signatures into a single signature. We proposed an identity-based aggregate signature scheme based on the bilinear pairings, which has a lower verification cost compared with the existing identity-based aggregate signatures. We proved that the proposed signature scheme is secure against existential forgery under adaptively chosen message and ID attack in the random oracle model, assuming that the Computational Diffie-Hellman problem is hard to solve.

Key words: Identity-based signature, Aggregate signature, Bilinear pairings, Computational Diffie-Hellman problem