A generic construction of identity-based proxy signature scheme in the standard model

Recently, numerous identity-based proxy signature (IDPS) schemes are constructed by direct methods or generic methods. However, most of them are proved only to be secure in the random oracle model or are involved high computational cost. In this paper, we present a novel and generic construction method of IDPS scheme secure in the standard model from any identity-based signature (IDS) scheme. The security of IDPS scheme constructed by our method is based on the security of original IDS scheme. The computational cost of constructing an IDPS scheme is almost the same as that of constructing an original IDS scheme. Compared with other existing IDPS schemes constructed by direct methods or other generic methods, our IDPS scheme has better performance: signature length and computational cost of our IDPS scheme are almost half of other existing IDPS schemes. What is more, our method can be applied to construct other identity-based proxy cryptosystems.