Patent ID: 7769880

Claim:
A computer-implemented method comprising: receiving a control flow request from a client; establishing a control flow responsive to the control flow request, the control flow establishing an exchange of a protected media content with the client using a Real Time Streaming Protocol (RTSP) for streaming, the establishing comprising: receiving, from the client, a license request message in the body of an RTSP DESCRIBE request; sending, to the client, a description using an RTSP Session Description Protocol (SDP) which includes a license response message that contains a license; communicating the protected media content to the client using a data flow, wherein the data flow uses a transport protocol, wherein the communicating comprises streaming and the transport protocol comprises Real Time Transport Protocol (RTP) with the protected media content encapsulated in an RTP packet, the RTP packet containing encryption parameters used in a decryption process to decrypt the protected media content; and sending to the client an RTSP ANNOUNCE request to change a protected media content policy or both a protected media content policy and a protected media content format associated with the protected media content during streaming of the protected media content, wherein the RTSP ANNOUNCE request comprises a new license response message that contains a new license, the new license dictating the changed protected media content policy that applies to the protected media content at a point during the streaming of the protected media content, wherein, when both the protected media content policy and the protected media content format are to be changed, the new license response message is embedded in an updated SDP description sent via the RTSP ANNOUNCE request, wherein the protected media content policy is selected from a group comprising enabling, disabling and changing a copy protection scheme.