ENCRYPTION KEY DISTRIBUTION METHOD IN MOBILE BROADCASTING SYSTEM AND SYSTEM FOR THE SAME

• US 20110206205A1
• Filed: 06/10/2009
• Published: 08/25/2011
• Est. Priority Date: 06/11/2008
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd. (Samsung Group)
• Original Assignee: Samsung Electronics Co. Ltd. (Samsung Group)
• Inventors: Lee, Byung-Rae, Hwang, Sung-Oh, Seleznev, Sergey Nikolayevich
• Granted Patent: US 9,191,204 B2
• Time in Patent Office: Days
• US Class Current: 380/278
• CPC Class Codes: G06F 21/10 Protecting distributed programs or content, e.g. vending or licensing of copyrighted material protection in video systems or pay television H04N7/16 ; Digital rights management [DRM]
• CPC Class Codes: H04L 2209/601 Broadcast encryption
• CPC Class Codes: H04L 2209/80 Wireless network architectures or network communication protocols for wireless network security H04W12/00
• CPC Class Codes: H04L 2463/101 applying security measures for digital rights management data processing systems or methods, specially adapted for commerce, e.g. marketing, shopping, billing, auctions or e-commerce G06Q30/00
• 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 9/0891 Revocation or update of secret information, e.g. encryption key update or rekeying
• CPC Class Codes: H04N 21/26613 for generating or managing keys in general key distribution for secret or secure communication involving central third party, e.g. key distribution center [KDC] or trusted third party [TTP] H04L9/083; network support of key management H04L63/06; key management for network security in communication control or processing H04W12/04
• 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: H04W 12/041 Key generation or derivation
• CPC Class Codes: H04W 4/06 Selective distribution of broadcast services, e.g. multimedia broadcast multicast service [MBMS]; Services to user groups; One-way selective calling services
• CPC Class Codes: H04W 4/50 Service provisioning or reconfiguring

Abstract

A method and a system for distributing an encryption key for service protection and content protection in a mobile broadcasting system are provided where a network generates a first encryption key when a broadcasting service is first provided to the terminal, and transmits a long term key message including the generated first encryption key to the terminal. Also, the network generates a second encryption key before the life-time of a first access value pair expires, and transmits a long term key message including the generated second encryption key to the terminal.

Claims

1. A method of distributing an encryption key for protecting a broadcasting service that is broadcast to a terminal in a mobile broadcasting system, comprising the steps of:

a network generating a first encryption key when the broadcasting service starts to be provided to the terminal, and transmitting a long term key message including the generated first encryption key to the terminal; and

the network generating a second encryption key before the life time of a first access value pair expires, and transmitting a long term key message including the generated second encryption key to the terminal.

2. The method as claimed in claim 1, wherein the life time of the first encryption key and the life time of the second encryption key are integer times the life time of a traffic encryption key derived from the first encryption key and the second encryption key.

3. The method as claimed in claim 1, wherein the first encryption key and the second encryption key are keys encrypted according to a subscriber management key that is shared only between the terminal and the network.

4. The method as claimed in claim 1, wherein the first encryption key and the second encryption key are program encryption keys derived from a service encryption key, and the network transmits a long term key message that includes the first encryption key and the second encryption key to the terminal according to a terminal'"'"'s purchase request for the first encryption key and the second encryption key.

5. The method as claimed in claim 4, wherein the terminal requests a purchase of the second encryption key from the network before the life time of the first encryption key expires.

6. The method as claimed in claim 1, wherein the first encryption key and the second encryption key are derived from a key seed pair optionally generated in the network, and include a key domain ID, a key seed pair ID, and a traffic encryption key.

7. A method of distributing an encryption key for protecting a broadcasting service that is broadcast to a terminal in a mobile broadcasting system, comprising the steps of:

verifying a long term key message using a subscriber management key if the long term key message is received from a network;

performing replay detection if the long term key message is valid;

confirming validity of an encryption key included in the long term key message using a security function if the replay detection succeeds; and

decoding the encryption key, generating and storing a traffic encryption key from the encryption key if the encryption key is valid.

8. The method as claimed in claim 7, further comprising the steps of:

the terminal transmitting a request message for requesting a new traffic encryption key to the security function; and

the security function transmitting the new traffic encryption key to the terminal in response to the request message.

9. The method as claimed in claim 8, wherein the request message includes a key domain ID and a traffic encryption key ID.

10. A mobile broadcasting system for protecting a broadcasting service, comprising:

a network generating a first encryption key when the broadcasting service is provided, transmitting a long term key message including the generated first encryption key, generating a second encryption key before the life time of a first access value pair expires, and transmitting a long term key message including the generated second encryption key; and

a terminal verifying the long term key message received from the network, decoding the encryption key included in the long term key message using a security function, and generating and storing a traffic encryption key from the encryption key.

11. The mobile broadcasting system as claimed in claim 10, wherein the life time of the first encryption key and the life time of the second encryption key are integer times the life time of a traffic encryption key derived from the first encryption key and the second encryption key.

12. The mobile broadcasting system as claimed in claim 11, wherein the first encryption key and the second encryption key are keys encrypted according to a subscriber management key that is shared only between the terminal and the network.

13. The mobile broadcasting system as claimed in claim 10, wherein the first encryption key and the second encryption key are program encryption keys derived from a service encryption key, and the network transmits a long term key message that includes the first encryption key and the second encryption key to the terminal according to a terminal'"'"'s purchase request for the first encryption key and the second encryption key.

14. The mobile broadcasting system as claimed in claim 13, wherein the terminal requests a purchase of the second encryption key from the network before the life time of the first encryption key expires.

15. The mobile broadcasting system as claimed in claim 10, wherein the first encryption key and the second encryption key are derived from a key seed pair optionally generated in the network, and include a key domain ID, a key seed pair ID, and a traffic encryption key.

16. The mobile broadcasting system as claimed in claim 10, wherein the terminal transmits a request message for requesting a new traffic encryption key to the security function, and the security function transmits the new traffic encryption key to the terminal in response to the request message.

17. The mobile broadcasting system as claimed in claim 16, wherein the request message includes a key domain ID and a traffic encryption key ID.