certified output protection protocol (copy protection) (COPP)

Certified Output Protection Protocol (COPP) is a copy protection developed by Microsoft to secure the data transfer between the playback software and the graphics card.

COPP works in the encryption between software and graphics card with a public key procedure with the RSA procedure with 128 bits. In this process, the graphics card with the COPP copy protection informs the software about its connections.

The film industry can specify the playback options and their resolution for each individual port. If the graphics card also has a Copy Generation Management System( CGMS), then the provider can determine whether a TV program may be recorded and at what resolution it may be played back via protected connections. The possibilities go so far that films can be played back, for example, via one connection with full resolution and via another with simple resolution.

To prevent the COPP-protected data stream from being diverted and stored via a virtual graphics card, the COPP protocol examines the data stream for manipulation.