研究成果

In modern cryptography, information-theoretic security is formalized by means of some probability (e.g., success probability of adversary’s guessing) or some information-theoretic measure (e.g., Shannon entropy), and the study on cryptographic protocols with information-theoretic security is one of effective applications of the probability theory, statistics, and information theory. In this paper, we study the blind authentication code (BA-code), a kind of information-theoretically secure authentication protocols, in which verifier’s secret keys are not required. For realizing it, we utilize a unidirectional low-bandwidth auxiliary channel which is called a manual channel. Specifically, in this paper we propose a model, a security definition, and a construction of BA-codes in the manual channel model. Furthermore, we consider BA-codes in other models, i.e., the noisy channel model and the bounded storage model, in which no verifier's secret key is required.