System for securing access to data streams

摘要

A method for protecting digital content is described. The method includes receiving compressed encrypted digital content, determining an output format based, at least in part, on all of the following: a user-requested output format; received control information; and a rule determining whether a clear compressed output format is allowedand producing output from the compressed digital content based on a result of the determining, wherein, if the rule does not allow clear compressed output format, the compressed encrypted digital content is provided in a form which prevents production of clear compressed output in the producing step. Related apparatus and methods are also described.

主权项

1. A digital content receiver (DCR) comprising:
a local scrambling descrambler; a broadcast descrambler receiving an output produced by the local scrambling descrambler; a local scrambler; a combined extra encryption algorithm decryptor and decoder/decompressor (XDDC); and a switch operative to provide an output of the broadcast descrambler to exactly one of the local scrambler and the XDDC, wherein the DCR is operative to receive control information and compressed encrypted digital content, and at least the setting of the switch is determined, at least in part, by the control information, and the DCR is operative to produce an output based on all of the following:
the compressed digital content;a user-requested output format;the received control information; anda rule determining whether a clear compressed output format is allowed, and if the rule does not allow clear compressed output format, the compressed encrypted digital content is provided to the DCR in a form which prevents production of clear compressed output as the output of the DCR.