An efficient identity-based signature scheme with batch verifications

Abstract

Mapping messages or a user's identity into a point on elliptic curves is required by many pairing-based cryptographic schemes. In most of pairing-based schemes, this requirement is realized by a special hash function, MapToPoint function. However, the efficiency of the MapToPoint function is much lower than the general hash functions. In this paper, we propose a new identity-based signature (IBS) scheme without MapToPoint function which speeds up extracting secret key and verifying the signatures. The security of the proposed scheme depends on a complex assumption similar to k-CAA. Furthermore, the proposed scheme also supports batch verifications such that multiple signatures on distinct messages for distinct users are verified simultaneously. The results show that batch verifications on the proposed IBS scheme is much faster than other IBS schemes.