Abstract: In most of the existing multi-proxy multi-signature (MPMS) schemes,the same proxy group is delegated the proxy right to sign by all the original members．Nevertheless,in many practical applications,original signer often demands to designate the proxy group in his own organization which is different from others’．It is seldom considered in the MPMS schemes．In this paper,we proposed a MPMS scheme with different proxy groups．Furthermore,in our scheme,when the final proxy signature is being authenticated,a group of specified verifiers have the access．To proved the safety of the new scheme,we improved a security model to testify that the new one is secure based on the computational Diffie-Hellman assumption．Compared with the previous scheme,the new one offers tighter safety and better computational efficiency.

Key words: Cryptography,Multi-proxy multi-signature (MPMS),Proxy group