Abstract: Verifiably encrypted signature can be used in secure electronic transactions. We presented the first efficient identity-based verifiably encrypted signature scheme which has the properties of verifiability and recoverability. We gave a security model with precise definitions and showed that the scheme is secure under the computational Bilinear Diffie-Hellman assumption without random oracles.

Key words: Verifiably encrypted signature, Security model, Computational diffie-Hellman problem, Bilinear map