Conditional access method and apparatus of a receiver system for controlling digital TV program start time

• US 7,809,942 B2
• Filed: 04/05/2005
• Issued: 10/05/2010
• Est. Priority Date: 12/27/2001
• Status: Active Grant

• Current Assignee: ARRIS Enterprises LLC (CommScope Holding Company, Inc.)
• Original Assignee: GoBackTV, Inc. (CommScope Holding Company, Inc.)
• Inventors: Field, Michael, Lin, Xu Duan, Baran, Paul, Pickens, John
• Primary Examiner(s): Cervetti; David Garcia
• Application Number:
  US11/098,787
• Publication Number:
  US 20050198680A1
• Time in Patent Office: 2,009 Days
• Field of Search: 713/160, 713/151, 713/182, 713/176, 713/167, 380/210, 380/201, 380/239, 380/25, 380/277, 380/281, 725/131, 725/25, 725/31, 725/88, 725/110, 725/138, 726/27
• US Class Current: 713/160
• CPC Class Codes: H04L 63/068 using time-dependent keys, e.g. periodically changing keys cryptographic mechanisms or cryptographic arrangements for controlling usage of secret information H04L9/088
• CPC Class Codes: H04L 63/10 for controlling access to devices or network resources
• CPC Class Codes: H04L 65/1101 Session protocols
• CPC Class Codes: H04L 65/612 for unicast
• CPC Class Codes: H04N 21/2318 using striping
• CPC Class Codes: H04N 21/2326 Scheduling disk or memory reading operations
• CPC Class Codes: H04N 21/23406 involving management of server-side video buffer
• CPC Class Codes: H04N 21/2347 involving video stream encryption
• CPC Class Codes: H04N 21/2362 Generation or processing of Service Information [SI]
• CPC Class Codes: H04N 21/2365 Multiplexing of several video streams
• 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 21/4347 Demultiplexing of several video streams
• CPC Class Codes: H04N 21/47202 for requesting content on demand, e.g. video on demand
• CPC Class Codes: H04N 21/6405 Multicasting data broadcast and multicast in packet switching networks H04L12/18
• CPC Class Codes: H04N 21/6587 Control parameters, e.g. trick play commands, viewpoint selection
• CPC Class Codes: H04N 7/17318 Direct or substantially direct transmission and handling of requests
• CPC Class Codes: H05K 1/0275 Security details, e.g. tampering prevention or detection
• CPC Class Codes: H05K 1/144 Stacked arrangements of planar printed circuit boards
• CPC Class Codes: H05K 1/185 Components encapsulated in the insulating substrate of the printed circuit or incorporated in internal layers of a multilayer circuit semiconductor chips encapsulated by interconnect and support structures H01L23/5389, H01L24/00
• CPC Class Codes: H05K 2201/10151 Sensor

Abstract

A conditional access method and apparatus for use with a system for controlling of digital TV program start time. Subscriber access is authorized to digital program streams. Content are divided into a plurality of working periods. Each working period of the plurality of working periods is scrambled with a different working key. A working key of a given period is delivered ahead of the given period. The working key is synchronized with scrambling control bits in an header. working keys are inserted into an entitlement control message (ECM) packet, and the ECM packet is encrypted using a service key. A time period is inserted into the ECM packet during which the service key is valid. A service key is inserted in an entitlement.

Claims

1. A conditional access method for use with a system for controlling of digital television program start time, for authorizing subscriber access to digital program streams, comprising the steps of:

dividing content into a plurality of working periods;

scrambling different working periods of the plurality of working periods with a different working keys, with the working keys synchronized with scrambling control bits in a content packet header;

inserting working keys into entitlement control message (ECM) packets;

encrypting the ECM packet using service keys at a distribution hub that uses quadrature amplitude modulation to deliver at least video on demand to a particular subscriber cluster;

delivering the working keys via a network to subscriber devices ahead of the working periods to which they apply;

inserting, in an entitlement management message (EMM) packet, a service key for decrypting the ECM packets;

encrypting the EMM packet using a user-specific key for an individual subscriber device to which the EMM packet is sent;

periodically sending EMM packets having new service keys usable by a group of individual subscribers from the distribution hub via a network to the subscriber devices, such that the new service keys have a limited distribution area, which reduces incentives for pirating;

and

authenticating the EMM packet with a digital signature of a valid headend.

2. The method as set forth in claim 1, with the step of scrambling including the step of scrambling each working period of the plurality of working periods with a different working key, respectively, with a working key of a given period delivered ahead of the given period, with the working key synchronized with scrambling control bits in an motion pictures experts group “

MPEG”

header, indicating an odd or even period key.

3. The method as set forth in claim 1, further including the step of providing the ECM packet in-band with content for which the ECM packet provides the service key.

4. The method as set forth in claim 1, further including the step of delivering the EMM packet in-band.

5. The method as set forth in claim 1, further including the step of delivering the EMM packet out-of-band.

6. The method of claim 1, wherein the subscriber cluster includes up to 12800 subscribers.

7. The method of claim 1, wherein the subscriber cluster includes under 500 homes.

8. The method of claim 1, wherein the subscriber cluster includes under 500 subscribers.

9. The method of claim 1, wherein the subscriber cluster includes up to 12800 subscribers.

10. The method of claim 1, wherein the subscriber cluster includes under 500 homes.

11. The method of claim 1, wherein the subscriber cluster includes under 500 subscribers.

12. A conditional access apparatus for use with a system for controlling of digital TV program start time, with for authorizing subscriber access to digital program streams comprising:

a dividing module running on a system that divides content into a plurality of working periods;

a scrambling module that scrambles different working periods using different working keys, with the working keys synchronized with scrambling control bits in a content packet header;

an ECM forming module that inserts working keys into entitlement control message (ECM) packets;

a first encrypting module running on a distribution hub that encrypts the ECM packets using service keys, wherein the distribution hub uses quadrature amplitude modulation to deliver at least video on demand to a subscriber cluster;

an EMM forming module that inserts a service key used to decrypt the ECM packet into an entitlement management message (EMM) packet;

an encrypting and signing module running on a system that encrypts the EMM packet using a user-specific key for an individual subscriber device to which the EMM packet is sent and signs the EMM packet using a key for a valid headend;

an EMM transmitter that periodically sends EMM packets having new service keys from the distribution hub to a group of individual subscribers in the subscribe cluster, whereby the new service keys have a limited distribution area, which reduces incentive for pirating.

13. The apparatus as set forth in claim 12, with the scrambling means including means for scrambling each working period of the plurality of working periods with a different working key, respectively, with a working key of a given period delivered ahead of the given period, with the working key synchronized with scrambling control bits in an MPEG header, indicating an odd or even period key.

14. The apparatus as set forth in claim 12, further including means for providing the ECM packet in-band with content for which the ECM packet provides the service key.