scope:

This Technical Specification contains the definition of the TPEG Conditional Access Information (CAI) application. It enables dedicated conditional access data, such as management messages (e.g. Control Words and Entitlement Control Messages) to be delivered to recipient client devices. This TPEG application is designed for a service provider to: establish setup, prolongation or revocation of services to a specific client device, using a limited capacity unidirectional broadcast channel and without recourse to service-client handshaking.

This TPEG application defines:

- the logical channel, for the transmission of the additional CA information (CAI);

- how the CAI is linked and synchronized to the scrambled content.

This Technical Specification is related to conditional access applied at the service component level of a TPEG service. It is an open design for the integration of various different conditional access systems, externally specified, which are signalled by the TPEG service Encryption Indicator to allow client devices to operate correctly.