Patent ID: 7773750

Claim:
A method for multimedia transmission, comprising: generating at least two copies of a multimedia stream to render first and second clear stream copies; sending the first clear stream copy to a first conditional access (CA) component to encrypt the entire first clear stream copy to render a first completely encrypted stream; sending the second clear stream copy to a second conditional access (CA) component to encrypt the entire second clear stream copy to render a second completely encrypted stream; identifying predetermined portions of the multimedia stream, the predetermined portions being a subset of portions of the multimedia stream and having respective encrypted versions in the first completely encrypted stream and in the second completely encrypted stream; obtaining the encrypted versions of the predetermined portions from the first completely encrypted stream; obtaining encrypted versions of the predetermined portions from the second completely encrypted stream; substituting the encrypted predetermined portions obtained from both the first and second completely encrypted streams for the predetermined portions in the multimedia stream or in a duplicate clear copy thereof to render a transmission stream that is only partially encrypted for transmission thereof.