METHOD FOR MANAGING KEY RECOVERY RIGHT, ITS SYSTEM AND PROGRAM RECORDING MEDIUM

摘要

PROBLEM TO BE SOLVED: To realize key recovery for a long time even when there is a change such as deletion or addition of a group in a group to which a user belongs in a key deposition type recovery method. ;SOLUTION: When a key generating agency 1 receives a key generating request from a user, the agency 1 generates a key, and provides an identifier of a group identified by the user and to which the user belongs and a key generating agency identifier to the key as label information, and requests a key storage agency 21 for its storage of the encrypted key. When the user receives a recovery request from a key recovery function 4, a retrieval means 24 retrieves a key from the key storage agency 21 and acquires it, and when the label information of the key matches the group identifier to which the user belongs, a recovery right retrieval means 8 discriminates a recovery request to be legal. When the key recovery agency 4 receives a notice of group deletion, the agency 4 relates the group to other related group.;COPYRIGHT: (C)2000,JPO