Simple Certificateless Signature with Smart Cards

A certificateless public key cryptosystem (CL-PKC) was proposed for the first time in 2003, and since then it has been attracted. But in fact most CL-PKC is implemented using the pairing technique. So it is difficult so far to apply CL-PKC to an existing encryption system that uses the conventional encryption method such as RSA. Needless to say, it is also difficult in even the system with smart cards. In this paper we propose the signature scheme with the RSA based smart card in the simple CL-PKC. Our scheme does not have user´s public key certificate as well as the ID-based cryptography. Also, it has some advantages that there is no escrow problem which occurs in the ID-based cryptography,and that even the manager cannot generate user´s falsified signature without changing user´s public key.