Partial encryption and PID mapping
First Claim
1. A method of producing an encrypted television signal, comprising:
- receiving a plurality of encrypted samples of the television program, the samples being encrypted under a first encryption method;
receiving a duplicate of the plurality of encrypted samples of the television program, the duplicate of the plurality of encrypted samples being encrypted under a second encryption method; and
combining the plurality of encrypted samples and the duplicate of the plurality of encrypted samples with an unencrypted portion to produce the encrypted television signal as an output.
1 Assignment
0 Petitions
Accused Products
Abstract
An encryption arrangement for multiple encryption of television programs. A system according to embodiments of the present invention multiple encrypts only a portion of the data required for full presentation of a television program to permit coexistence of multiple conditional access encryption systems associated with multiple manufacturer'"'"'s set-top boxes within a single system. PID mapping techniques are used to distinguish between multiple encryptions. By only encrypting a portion of the program, dramatically less bandwidth is consumed than the alternative of multiple encryption of all program data, thus permitting a larger number of programs to be carried over the same bandwidth while permitting coexistence of multiple conditional access systems in a single cable television system.
342 Citations
42 Claims
-
1. A method of producing an encrypted television signal, comprising:
-
receiving a plurality of encrypted samples of the television program, the samples being encrypted under a first encryption method; receiving a duplicate of the plurality of encrypted samples of the television program, the duplicate of the plurality of encrypted samples being encrypted under a second encryption method; and combining the plurality of encrypted samples and the duplicate of the plurality of encrypted samples with an unencrypted portion to produce the encrypted television signal as an output. - View Dependent Claims (2, 3, 4, 5)
-
-
6. A method of producing a multiple encrypted television signal, comprising:
-
receiving a plurality of unencrypted packets; receiving a plurality of multiple encrypted packets, wherein the multiple encrypted packets comprise first encrypted packets encrypted under a first encryption method and second encrypted packets are encrypted under a second encryption method, and wherein both the unencrypted and at least one of the first and second encrypted packets are required to decode the television signal; and combining the plurality of unencrypted packets with the plurality of multiple encrypted packets to produce the multiple encrypted television signal as an output. - View Dependent Claims (7, 8, 9)
-
-
10. A method of encrypting content, comprising:
-
identifying a portion of the content to encrypt according to a selection algorithm where less than 100% of the content is encrypted; encrypting the identified content portion according to a first encryption method to produce a first encrypted content portion; encrypting the identified content portion according to a second encryption method to produce a second encrypted content portion; and combining an unencrypted content portion along with the first and second encrypted content portions to produce partially multiple encrypted content. - View Dependent Claims (11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28)
-
-
29. A method of encrypting digital audio and video content, comprising:
-
encrypting the digital audio and video content according to a first encryption method and a second encryption method to produce a first encrypted digital audio and video content portion and a second encrypted digital audio and video portion, respectively; and combining the first encrypted digital audio and video content portion and the second encrypted digital audio and video content portion with an unencrypted digital audio and video content portion to produce an output signal of multiple partially encrypted digital audio and video content. - View Dependent Claims (30, 31)
-
-
32. A method of managing multiple access control systems with an audio visual content distribution system, comprising:
-
identifying a portion of the content to replicate for each of a plurality of access control systems according to a selection algorithm wherein less than 100% of the content is replicated and wherein the portion that is not identified for replication is an unencrypted portion; and replicating the identified portion twice to create a first replicated identified portion and a second replicated identified portion; and providing an output signal comprising the first replicated portion and the second replicated portion. - View Dependent Claims (33, 34, 35, 36, 37, 38)
-
-
39. An apparatus for generating a multiple encrypted packetized digital television signal, comprising:
-
means for receiving a first plurality of unencrypted packets; a first encryptor for encryption of a second plurality of packets encrypted under a first encryption method; a second encryptor for encryption of a third plurality packets encrypted under a second encryption method; and wherein the packets encrypted under the first and second encryption methods are duplicate packets, and wherein the packets are selected for encryption using a selection criterion; and a multiplexer that combines the first, second and third plurality of packets into a transport data stream as an output thereof. - View Dependent Claims (40, 41, 42)
-
Specification