Partial dual encrypted stream utilizing program map tables

• US 7,496,198 B2
• Filed: 12/06/2005
• Issued: 02/24/2009
• Est. Priority Date: 04/03/1995
• Status: Expired due to Fees

• Current Assignee: Tech 5 SAS
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Pinder, Howard, Evans, Jonathan Bradford, Woodward, William D. Jr., Wasilewski, Anthony J.
• Primary Examiner(s): Chai; Longbit
• Application Number:
  US11/275,051
• Publication Number:
  US 20060233369A1
• Time in Patent Office: 1,176 Days
• Field of Search: 380/202, 380/216
• US Class Current: 380/216
• CPC Class Codes: H04J 2203/008 Support of video
• CPC Class Codes: H04L 2463/101 applying security measures for digital rights management
• CPC Class Codes: H04L 63/0428 wherein the data content is protected, e.g. by encrypting or encapsulating the payload
• CPC Class Codes: H04L 63/062 for key distribution, e.g. centrally by trusted party cryptographic mechanisms or cryptographic arrangements for key distribution involving a central third party H04L9/0819
• CPC Class Codes: H04N 21/2265 Server identification by a unique number or address, e.g. serial number network arrangements, protocols or services for addressing or naming H04L61/00
• CPC Class Codes: H04N 21/23476 by partially encrypting, e.g. encrypting the ending portion of a movie
• CPC Class Codes: H04N 21/235 Processing of additional data, e.g. scrambling of additional data or processing content descriptors
• CPC Class Codes: H04N 21/2362 Generation or processing of Service Information [SI]
• CPC Class Codes: H04N 21/23897 by partially encrypting, e.g. encrypting only the ending portion of a movie
• CPC Class Codes: H04N 21/26606 for generating or managing entitlement messages, e.g. Entitlement Control Message [ECM] or Entitlement Management Message [EMM] arrangements for conditional access to broadcast information or to broadcast-related services H04H60/14
• CPC Class Codes: H04N 21/426 Internal components of the client ; Characteristics thereof H04N5/44 takes precedence
• CPC Class Codes: H04N 21/435 Processing of additional data, e.g. decrypting of additional data, reconstructing software from modules extracted from the transport stream
• CPC Class Codes: H04N 21/43607 Interfacing a plurality of external cards, e.g. through a DVB Common Interface [DVB-CI]
• CPC Class Codes: H04N 21/4405 involving video stream decryption
• CPC Class Codes: H04N 21/44055 by partially decrypting, e.g. decrypting a video stream that has been partially encrypted
• CPC Class Codes: H04N 21/4524 involving the geographical location of the client retrieval from the Internet by querying based on geographical locations G06F16/9537; systems specially adapted for using geographical information in broadcast systems H04H60/70; protocols in which the network application is adapted for the location of the user terminal in communication control or processing H04L67/52; services making use of the location of users or terminals in wireless networks H04W4/02; locating users or terminals in wireless networks H04W64/00
• CPC Class Codes: H04N 21/63345 by transmitting keys key distribution for secret or secure communication H04L9/08; network support of key management H04L63/06
• CPC Class Codes: H04N 7/162 Authorising the user terminal, e.g. by paying; Registering the use of a subscription channel, e.g. billing
• CPC Class Codes: H04N 7/163 by receiver means only
• CPC Class Codes: H04N 7/1675 Providing digital key or authorisation information for generation or regeneration of the scrambling sequence pseudo-random number generators in general G06F7/58
• CPC Class Codes: H04N 7/17354 : in an intermediate station common to a plurality of user terminals

Abstract

The present invention is suitable for use in a partial dual encrypted system. The present invention allows for two different decryption devices (e.g., an incumbent, or first, set-top and an overlay, or second, set-top) to be located in a single system having an incumbent encryption scheme and a second encryption scheme. Each set-top is designed to decrypt the first or second proprietary encryption schemes, respectively. In accordance with the present invention, the second set-top utilizes a novel program map table to ensure that the second set-top chooses correct elementary streams in the partial dual-encrypted stream (i.e., a combined stream including a first encrypted stream, a second encrypted stream, and a clear stream) for a desired program.

Claims

1. A communications system for encoding and transmitting a partial dual-encrypted program stream, the communications system for receiving a clear program stream, the clear program stream including a plurality of programs, each program including a plurality of packets, the communications system comprising:

a first encryptor for receiving the clear program stream and encrypting the plurality of programs according to a first encryption scheme;

a second encryptor for receiving the clear program stream and encrypting the plurality of programs according to a second encryption scheme;

a first demultiplexer for demultiplexing the first encrypted plurality of program streams to produce a plurality of first encrypted programs;

a second demultiplexer for demultiplexing the second encrypted plurality of program streams to produce a plurality of second encrypted programs;

a third demultiplexer for demultiplexing the clear program stream to produce a plurality of clear programs; and

a plurality of identifier devices, each identifier device receiving at least one particular program from the plurality of first encrypted programs and receiving the same at least one particular program from the plurality of second encrypted programs and receiving the same at least one particular program from the plurality of clear programs, wherein the at least one particular program received by each identifier device is different in a form of encryption, each identifier device configured to;

identify critical packets in the at least one particular program from the plurality of clear programs; and

pass rackets of the clear program stream that are not critical rackets;

wherein when the critical packet is identified by a packet identifier in the clear program stream, drop the identified critical packets in the at least one particular program from the plurality of the clear programs and pass corresponding critical packets in the at least one particular program from the plurality of first encrypted programs and in the at least one particular program from the plurality of second encrypted programs.

2. The communications system of claim 1, each identifier further configured to:

responsive to identification of non-critical packets in the particular program received from the clear programs, pass the non-critical packets in the particular program received from the clear programs and drop corresponding non-critical packets in the particular program received from the first and second encrypted programs.

3. The communications system of claim 1, further comprising a multiplexer for multiplexing the passed clear program packets, the first encrypted program packets, and the second encrypted program packets.

4. The communications system of claim 1, each identifier further comprising a remapper configured to encode a second encrypted program map table including audio and video packet identifiers for each program of the second encrypted program, and further configured to encode a program map table of the first encrypted program, and further configured to encode a program map table of the clear program.