3.2.5.3 License Retrieval Details

The receiver MUST perform license retrieval using the following steps:

  1. The receiver MUST send a license request message to the transmitter that contains the receiver's version number of the WMDRM: Network Devices Protocol, its device certificate, serial number, a 128-bit Rights ID value, the intended action of the receiver (such as "Play"), and its version of the CRL, if it has a CRL.

  2. If the receiver has transmitting capabilities, the license response message MAY include a WMDRM-ND CRL. If a WMDRM-ND CRL is included in the response, it MUST be an updated version of the WMDRM-ND CRL. In this case, the receiver MUST compare its own version of the CRL to the version of the CRL that the transmitter included in the license response message. If the transmitter's CRL version number is higher than the receiver's CRL and the transmitter's CRL is valid, then the receiver MUST install the new CRL.

  3. If the license contains a RIV object (defined in the XMR specification [XMR]), the receiver MUST compare the RIV specified in the license against the version of its own RIV structure. If the transmitter's RIV version number is higher than the receiver's RIV, or if the receiver does not have a RIV structure, the receiver MUST successfully complete the revocation list update procedure according to the rules in revocation list before it is allowed to request content from the transmitter.