METHOD AND DEVICE FOR CONFIRMING EFFECTIVENESS OF PUBLIC KEY CERTIFYING CARD, AND RECORDING MEDIUM RECORDING EFFECTIVENESS CONFIRMING PROGRAM FOR PUBLIC KEY CERTIFYING CARD

摘要

PROBLEM TO BE SOLVED: To enable effectiveness of public key certifying cards of all communication parties to be confirmed by the certain one set value fixed by a user side in order to prevent the reduction of reliability for confirming effectiveness of public key certifying cards due to the difference of the time difference which is to be caused by the difference of a CRT issuing interval and to dispense with the managing of the CRL issuing interval of an identification system. ;SOLUTION: In the effectiveness of public key certifying cards confirming device confirming effectiveness of the public key certifying card of a transmitting user in the communication between users using an identification system, a time stamp time difference value calculating means 5 calculating a time difference value from the date when a public key certifying card being an object whose effectiveness is confirmed is obtained till the present time and a time stamp time difference value comparing means 6 which compares the time difference value calculated in the means 5 with the time difference allowed value preliminarily set by a user and regards the pertinent public key certifying card to be effective when the time stamp time difference value is smaller than the time difference allow value and regards the card to be ineffective when the time stamp time difference value is larger than the time difference allowed value, are provided.;COPYRIGHT: (C)2000,JPO