Binary Information Press
In 1984, the researcher proposed a kind of identity based cryptosystems, where the public key can be an arbitrary string such as an email address or a telephone number, etc. In 2005, the researchers proposed a Fuzzy identity-based encryption, which is a generalization to identity-based cryptosystem. There exists a demerit in normal attribute based signature, whose length of the signature depends on the largest size of attributes set. In this paper, an attribute-based signature scheme with constant size is proposed. It is proved to be unforgeable and unconditionally anonymous in the standard model. The security of the scheme is based on Computational Diffie-Hellman (CDH) problem.