Identity-based Signature Scheme with Partial Message Recovery in the Standard Model

Based on Gentry' s identity based encryption scheme and its variants, an identity-based signature scheme with partial message recovery is proposed. In this scheme, the total length of the original message and the appended signature is shortened, and the discarded message is recovered in reasonable time. The proposed scheme is proven to be existentially unforgeable under adaptive chosen message attacks in the standard model and its security depends on q-strong Diffie-Hellman intractability assumption. Compared with the existing identitybased signatures in the standard model, this scheme has a shorter length of message and signature, and is applied to low-bandwidth communication environments.