Efficient short proxy signature scheme based on multilinear map

Abstract Proxy signature allows an entity to delegate its signing capability to another entity called proxy signer which can produce a signature on behalf of the delegator. In this paper, based on efficiently computable non-degenerate multilinear map, we put forth a novel short proxy signature scheme. Most remarkable point in our scheme is that the scheme can achieve short length signature, it is very suitable for the restrained devices in the sensor network. And the scheme is shown to be secure. The security of the scheme is closely related to Boneh-Silverberg signature and Boneh-Lynn-Shacham (BLS) signature which are related to the computational Diffie-Hellman problem (CDH). In terms of computational cost and the length of the signature, only one exponentiation is needed in the signing phase. And the size of proxy signature is 160 bit which is as short as the classic BLS signature. To the best of my knowledge, it is the shortest proxy signature.