A novel identity-based signature with message recovery from RSA

Several identity-based signature schemes with message recovery have already been proposed so far, and most of the existing schemes are constructed from the bilinear pairings. Although the bilinear pairings are quite useful in the study of cryptography, it is hard to implement and computationally expensive. In this paper, we describe a novel identity-based signature scheme with message recovery from RSA, which does not need to employ the bilinear pairings. Under the hardness of RSA problem, our scheme satisfies existential unforgeable against adaptive chosen identity and message attacks in the random oracle model. Furthermore, we extend our scheme for partial message recovery, such that it can deal with the messages of arbitrary length.