An information processing system and method for realizing an efficient processing by using an enabling key block (EKB) of a categorized tree structure. A path constituting a key tree having sub-trees sorted by category and managed by a category entity is selected, and an EKB composed of encrypted data on an upper-level key encrypted by a lower-level key on the selected path is created and provided to a device. A state change due to, e.g., a revocation in a category tree where an EKB defined in an EKB type definition list is processable is reported to an EKB use entity. An EKB requester can always carry out a processing on the basis of the latest EKB.
申请公布号
WO02052781(A1)
申请公布日期
2002.07.04
申请号
WO2001JP11237
申请日期
2001.12.21
申请人
SONY CORPORATION;ASANO, TOMOYUKI;OSAWA, YOSHITOMO;OISHI, TATEO;ISHIGURO, RYUJI;TAKI, RYUTA