Updating a revocation list to foil and adversary

• Main Author: M.A. EPSTEIN
• Format: Patent
• Language: Chinese; English
• Published: 11.08.2004
• Edition: 7
• Subjects: CALCULATING; COMPUTING; COUNTING; ELECTRIC COMMUNICATION TECHNIQUE; ELECTRIC DIGITAL DATA PROCESSING; ELECTRICITY; INFORMATION STORAGE; INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORDCARRIER AND TRANSDUCER; PHYSICS; TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHICCOMMUNICATION

用一种随机的方式处理和维护用于验证已经被撤销的一个访问标识符的列表，以降低在时间流逝之后一个被撤销的访问标识符被接受访问的可能性。当访问控制系统更新它的本地撤销列表时，使用一种非确定性的方法来确定本地撤销列表的结果内容。根据本发明的另一方面，撤销标识符的通信还基于一种撤销标识符的随机选择。以这种方式，仅仅时间的流逝将不必然导致先前被撤销的标识符变得重新可用。复制设备将变得"不可靠"，导致用户永远不能确保复制设备将"正常地"运行。根据本发明的另一方面，撤销的强制也被随机化。例如，访问控制系统开始可以向具有一个撤销标识符的设备提供内容资料，然后，在某个随后的随机时间上，终止传输。以这种方式，复制设备的用户永远不能确保可以完整地观看诸如电影的内容资料。 The lists used to verify whether an access identifier has been revoked are processed and maintained in a random fashion to reduce the likelihood of a revoked access identifier being accepted for access after a passage of time. When the access control system updates its local revocation list, a non-deterministic method is used to determine the resultant content of the local revocation list. In accordance with another aspect of this invention, the communication of the revoked identifiers is also based on a non-deterministic selection of revoked identifiers. In this manner, the mere passage of time will not necessary result in a prior revoked identifier becoming revived. The replicated device will become "unreliable", in that the user can never be assured that the replicated device will operate "properly". In accordance with another aspect of this invention, the enforcement of the revocation is also randomized. For example, the access control system may initially provide the content material to a device having a revoked identifier, then, at some random time later, terminate the transmission. In this manner, a user of a replicated device can never be assured that the content material, such as a movie, can be viewed in its entirety.