Charter Explores Session-Based Encryption

Charter senior director Jim Alexander is named as inventor on the patent application.

Charter Communications has developed a content encryption system that could help it reduce network resources required to deliver video-on-demand streams to multiple set-tops and display devices, according to a patent application published on Thursday.

Senior Director Jim Alexander is named as inventor on the patent application, titled, “Session-based encryption for delivering content on demand.”

Abstract: The specification and drawings present a new method, apparatus and software related product (e.g., a computer readable memory or storage device) for a session-based encryption (e.g., a common-tier encryption) for delivering a content (e.g., video, data, multi-media content and the like) on demand using multiple encryptors. According to an embodiment, the STB’s request for a VOD session may be routed by a session resource manager (SRM) to receive content from an appropriate encryptor chosen from multiple encryptors based on a predefined criteria. This approach can minimize a number of encryptions/encrytpion devices (such as ECM generators) needed in a cable network. However, the simulcrypt encryptor can be also used, if necessary, e.g., when CAS-only encryptors are fully loaded with a traffic.

Patent Application

Claims:

1. A method, comprising: receiving, by a session resource computing device from a requesting device, a request for a content and a required type of conditional access system (CAS) for decrypting the content by the requesting device, the required type of CAS being out of a plurality of CAS types, each CAS type being associated with a group of requesting devices and distinguishable by a unique entitlement control message (ECM); and choosing, by the session resource computing device, an encryptor out of a plurality of encryptor options for the required type of CAS using a predefined procedure, the chosen encryptor being associated at least with the required type of CAS for encrypting the requested content using at least a corresponding ECM for the required type of CAS to deliver the encrypted requested content to the requesting device for decrypting the content using the corresponding ECM.

2. The method of claim 1, wherein the requesting device is a set top box (STB), said request is a video on demand (VOD) request, and said content is a video content or a movie.

3. The method of claim 1, further comprising: providing, by the session resource computing device to a request server or a video on demand (VOD) server, said chosen encryptor for encrypting the requested content.

4. The method of claim 1, further comprising: sending, by the session resource computing device, said requested content to the chosen encryptor for said encrypting.

5. The method of claim 1, wherein said encrypting of said requested content being performed using a common-tier encryption.

6. The method of claim 5, wherein said common-tier encryption is used with one of a data encryption standard (DES) and an advanced encryption standard (AES

7. The method of claim 1, wherein said encrypted content is modulated using quadrature amplitude modulation (QAM) before being delivered to the requesting device.

8. The method of claim 1, wherein said plurality of CAS types includes type 1 and type 2, so that said plurality of encryptor options comprises three encryptor options including a CAS type 1 only encryptor, a CAS type 2 only encryptor and a simulcrypt encryptor associated with said CAS type 1 and type 2.

9. The method of claim 8, wherein the required type of CAS is the type 1, so that the type 1 only encryptor is chosen if it is determined that said type 1 only encryptor is not fully used and has enough capacity to encrypt the content.

10. The method of claim 8, wherein the required type of CAS is the type 1, so that the simulcrypt encryptor is chosen if it is determined that said type 1 only encryptor is fully used.

11. The method of claim 1, wherein said plurality of CAS types includes type 1, type 2 and type 3, so that said plurality of encryptor options comprises seven encryptor options including a CAS type 1 only encryptor, a CAS type 2 only encryptor, a CAS type 3 only encryptor, three simulcrypt encryptors associated with the CAS type 1 and type 2, with the CAS type 1 and type 3 and with the CAS type 2 and type 3, respectively, and one simulcrypt encryptor associated with the CAS type 1, type 2 and type 3.

12. The method of claim 1, wherein said content is a video content, a movie, a data content or a multi-media content.

13. An apparatus comprising: a processor; a storage medium for tangibly storing thereon program logic for execution by the processor, the program logic comprising: logic to receive, by a session resource computing device from a requesting device, a request for a content and a required type of conditional access system (CAS) for decrypting the content by the requesting device, the required type of CAS being out of a plurality of CAS types, each CAS type being associated with a group of requesting devices and distinguishable by a unique entitlement control message (ECM); and logic to choose, by the session resource computing device, an encryptor out of a plurality of encryptor options for the required type of CAS using a predefined procedure, the chosen encryptor being associated at least with the required type CAS for encrypting the requested content using at least a corresponding ECM for the required type of CAS to deliver the encrypted requested content to the requesting device for decrypting the content using the corresponding ECM.

14. The apparatus of claim 13, wherein the requesting device is a set top box (STB), said request is a video on demand (VOD) request, and said content is a video content or a movie.

15. The apparatus of claim 13, wherein said encryptor options are implemented as an encryptor bank comprising: a group of N CAS only encryptors of types 1 through N, where N is a finite integer of two or more; a group of k simulcrypt encryptors, each simulcrypt encryptor being associated with multiple types of the CAS types selected from types 1 through N, where k is a finite integer of one or more; and a group of N ECM generators, each providing a corresponding input ECM to each of the group of CAS only encryptors of types 1 through N, and multiple ECMs of the corresponding multiple types of the CAS types selected from types 1 through N.

16. The apparatus of claim 15, comprising said encryptor bank.

17. A non-transitory computer readable storage medium tangibly storing computer program instructions capable of being executed by a computer processor, the computer program instructions defining code for: method, comprising: receiving, by a session resource computing device from a requesting device, a request for a content and a required type of conditional access system (CAS) for decrypting the content by the requesting device, the required type of CAS being out of a plurality of CAS types, each CAS type being associated with a group of requesting devices and distinguishable by a unique entitlement control message (ECM); and choosing, by the session resource computing device, an encryptor out of a plurality of encryptor options for the required type of CAS using a predefined procedure, the chosen encryptor being associated at least with the required type of CAS for encrypting the requested content using at least a corresponding ECM for the required type of CAS to deliver the encrypted requested content to the requesting device for decrypting the content using the corresponding ECM.

18. The non-transitory computer readable storage medium of claim 17, wherein the requesting device is a set top box (STB), said request is a video on demand (VOD) request, and said content is a video content or a movie.

19. A method, comprising: receiving by a video on demand (VOD) server from a session resource manager, a chosen encryptor for encrypting a requested content of the VOD request for delivering said video content to a set top box (STB), said chosen encryptor being associated a required type of conditional access system (CAS), for decrypting the video content by the STB, the required type of CAS being out of a plurality of CAS types, each CAS type being associated with a group of STBs and distinguishable by a unique entitlement control message (ECM), wherein said encryptor is chosen out of a plurality of encryptor options for the required type of CAS using a predefined procedure, the chosen encryptor being associated at least with the required type of CAS and adapted for encrypting the requested video content using at least a corresponding ECM for the required type of CAS to deliver the encrypted requested video content to the STB for decrypting the content using the corresponding ECM; and sending, by the VOD server, said requested video to the chosen encryptor for said encrypting.

20. The method of claim 19, wherein said encrypting of said video content being performed using a common-tier encryption.