Patent ID: 8347404

Claim:
A method of checking revocation of a content device and transmitting data, the method comprising: receiving authentication information of a device requesting transmission of data, and authentication information of digital rights management (DRM) software that authorizes access of the data in the device; checking revocation of the device and the DRM software, based on the received authentication information, wherein the checking of the revocation further comprises: checking a device Certification Revocation List (CRL) related to a certificate of the device, where the CRL comprises a device identifier, a device public key, and a digital signature for the device and wherein the received authentication information of the device is compared with at least one of the device identifier, the device public key, and the digital signature for each of devices identified in the CRL; and checking a software revocation list (SRL) separate from the CRL and related to a certificate of the DRM software, where the SRL comprises a software identifier, a software public key, and a digital signature for the DRM software and wherein the received authentication information of the DRM software is compared with at least one of the software identifier, the software public key, and the digital signature for each of the DRM software identified in the SRL; authenticating the device based on the checking of the CRL; authenticating the DRM software based on the separate checking of the SRL; and transmitting the data to the device, when the device and the DRM software are not revoked and the authentication of the device and the DRM software succeeds.