Abstract: A new practical identification scheme based on bit commitment and Schnorr's one-time knowledge proof scheme　is presented. Here the use of Cut-and-Choose method and many random exam candidates in the identification protocol is replaced by a single challenge number. Therefore our identification scheme is more efficient and practical than the previous schemes. In addition, we prove the security of the proposed scheme under discrete logarithm assumption, thus clarify the cryptographic basis of the proposed scheme.

Key words: secret communications, identification scheme, discrete logarithm assumption