AUTHENTICATION METHOD AND SYSTEM

摘要

PROBLEM TO BE SOLVED: To use the completely same result as a ciphered result before initialization after a proper communication equipment initializes the number of times of authentication and to arbitrarily initialize the number of times of the authentication by another communication equipment as the proper commu nication equipment when the ciphered result of the case of initializing the num ber of times of the authentication of the proper communication equipment leaks. SOLUTION: A value ciphered by an authentication key in the communication equipment at the time of the service request of a previous time is stored in a storage device (S1), a communication processor performs the authentication by the value stored in the storage device at the time of service request issuance (S4) and the value for indicating the time of the initialization processing of the previous time is stored in the storage device (S5). At the time of an initialization request, the value for indicating the time of the initialization processing of the previous time, the value of the time at the present point of time and the value (S7) for which the time at the point of time is ciphered by the authentication key are used and the authentication is performed (S8).