Copy protection scheme for digital audio and video content authenticated HDCP receivers

• US 10,142,108 B2
• Filed: 06/17/2013
• Issued: 11/27/2018
• Est. Priority Date: 06/17/2013
• Status: Active Grant

• Current Assignee: Qube Cinema, Inc. (Qube Cinema Technologies Pvt., Ltd.)
• Original Assignee: Qube Cinema, Inc. (Qube Cinema Technologies Pvt., Ltd.)
• Inventors: Ramachandran, Rajesh, Kumar, Senthil
• Primary Examiner(s): Pham, Luu T
• Assistant Examiner(s): Baum, Ronald
• Application Number:
  US13/919,400
• Publication Number:
  US 20140372759A1
• Time in Patent Office: 1,989 Days
• Field of Search: 713171
• CPC Class Codes: H04L 9/30 Public key, i.e. encryption algorithm being computationally infeasible to invert or user's encryption keys not requiring secrecy
• CPC Class Codes: H04L 9/3226 using a predetermined code, e.g. password, passphrase or PIN network architectures or network communication protocols for supporting authentication of entities using passwords in a packet data network H04L63/083
• CPC Class Codes: H04N 21/25816 involving client authentication restricting access to computer systems by authenticating users using a predetermined code G06F21/33; cryptographic authentication protocols H04L9/32; networks authentication protocols H04L63/08; authentication in wireless network security H04W12/06
• CPC Class Codes: H04N 21/63775 for uploading keys, e.g. for a client to communicate its public key to the server key management H04L9/08; network support of key management H04L63/06
• CPC Class Codes: H04N 21/647 Control signaling between network components and server or clients; Network processes for video distribution between server and clients, e.g. controlling the quality of the video stream, by dropping packets, protecting content from unauthorised alteration within the network, monitoring of network load, bridging between two different networks, e.g. between IP and wireless real-time session protocols H04L65/1101

Abstract

A method of delivering digital audio and video content and a HDCP source device are disclosed herein. In one embodiment the method includes: (1) receiving an encryption key from a potential receiver of the digital audio and video content, (2) authenticating the potential receiver is an HDCP compliant device and (3) in addition to the authenticating, verifying the potential receiver is a trusted device for receiving the digital audio and video content.

Claims

1. A method of delivering High-bandwidth Digital Content Protection (HDCP) digital audio and video (DAV) content, comprising:

receiving, at a repeater physically separate from a source and potential receiver, an encryption key directly from said potential receiver of said HDCP DAV content;

authenticating, at said repeater, said potential receiver is an HDCP compliant device using said encryption key from said potential receiver and content decryption keys; and

verifying, at said repeater, said potential receiver is a trusted device for receiving said HDCP DAV content by comparing a unique identifier of said potential receiver to a list of trusted devices, said list of trusted devices stored in a memory of said repeater wherein said comparing is performed only by a processor of said repeater, said list of trusted devices transmitted to said repeater from said source of said HDCP DAV content along with said content decryption keys;

wherein said delivering of said HDCP DAV content to said authenticated HDCP compliant device is permitted by said repeater when only said unique identifier of said authenticated HDCP compliant device matches a trusted device of said list of trusted devices.

2. The method as recited in claim 1 wherein said list of trusted devices is locally stored in said repeater as a digitally signed file.

3. The method as recited in claim 1 wherein said unique identifier is a bit key selection vector (BKSV) of said potential receiver.

4. The method as recited in claim 1 wherein said receiving includes receiving said content decryption keys through a Key Delivery Message.

5. The method as recited in claim 4 wherein said Key Delivery Message includes said list of trusted devices and said verifying includes comparing a unique identification of said potential receiver to said list of trusted devices.

6. The method as recited in claim 1 wherein said list is stored in a memory of said source of said HDCP DAV content.

7. The method as recited in claim 1 wherein said verifying is performed in response to a change in state of a link for said delivering.

8. The method as recited in claim 1 wherein said list of trusted devices includes a unique representation of a bit key selection vector (BKSV).

9. The method as recited in claim 1 wherein said content decryption keys include a 40-bit key selection vector (KSV) and Device Private Keys.

10. A High-bandwidth Digital Content Protection (HDCP) system, comprising:

a source configured to deliver HDCP digital audio and video (DAV) content over a communication link to an HDCP receiver; and

a repeater physically separate from said source and receiver, coupled to said transmitter, comprising;

at least one key reservoir configured to authenticate said HDCP receiver using an encryption key received directly from said HDCP receiver and content decryption keys; and

a device confirmer, said device confirmer including a memory to store a list of trusted devices;

wherein;

said device confirmer is configured to determine if said authenticated HDCP receiver is a trusted device by comparing a unique identifier of said authenticated HDCP receiver with said stored list of trusted devices, wherein said comparing is performed only by a processor of said repeater,

said list of trusted devices is transmitted to said repeater from said source of said HDCP DAV content along with said content decryption keys; and

said device confirmer of said repeater permits delivery of said HDCP DAV content by said source to said authenticated HDCP receiver when only said unique identifier matches a trusted device of said stored list of trusted devices.

11. The HDCP device as recited in claim 10 wherein said authenticated HDCP receiver is a display.

12. The HDCP device as recited in claim 10 wherein said device confirmer is configured to determine if said HDCP receiver is said trusted device based on a BKSV thereof.

13. The HDCP device as recited in claim 12 wherein said device confirmer is configured to perform said determining based on said BKSV at a state change of said communication link.

14. The HDCP device as recited in claim 10 wherein said content decryption keys include a 40-bit key selection vector (KSV) and Device Private Keys.