Method and apparatus for supporting multiple broadcasters independently using a single conditional access system
View Patent ↗A method and apparatus for brokering the enablement of the communication of encrypted media programs from a plurality of independent broadcasters to a plurality of receivers is disclosed. The system makes use of a pairing key for each provided service, which is differently encrypted by a pairing server and by the broadcaster providing the service. The encrypted versions of the pairing key are decrypted in a first receiver module using information known to the pairing service but not the broadcaster and in a second receiver module using information known to the broadcaster. The pairing key is used to cryptographically bind the first and second receiver modules.
1. A method of brokering an enabling of communication of at least one encrypted media service of a group of encrypted media services from a plurality of broadcasters to a plurality of receivers, the at least one encrypted media service decryptable by a first receiver module securely communicating with a second receiver module according to a pairing key associated with a receiver of the plurality of receivers, comprising:
transmitting a first media service enabling request for a first media service from a broadcaster of the plurality of broadcasters to a broker independent from the broadcaster, the first media service enabling request comprising an identification of the receiver;
receiving a first encrypted version of the pairing key E S 1 [K p ] in the broadcaster from the broker, the first encrypted version of the pairing key E S 1 [K p ] decryptable by first information S 1 securely stored in the first receiver module of the receiver;
encrypting the pairing key with second information S 2 to generate a second encrypted version of the pairing key E S 2 [K p ] in the broadcaster, the second encrypted version of the pairing key E S 2 [K p ] decryptable by the second information S 2 securely stored in the second receiver module; and
transmitting the first encrypted version of the pairing key E S 1 [K p ] and the second encrypted version of the pairing key E S 2 [K p ] to the receiver;
wherein each media service in the group is enabled by a different pairing key K p .
2. The method of claim 1 , wherein the first media service is selected from a group consisting of:
a general broadcast service from the broadcaster, including access to a number of media channels as a baseline fee service;
a particular media program from the broadcaster; and
a particular set of media programs from the broadcaster.
3. The method of claim 2 , wherein the media service is encrypted according to a control word CW, and the method further comprising:
decrypting the first encrypted version of the pairing key E S 1 [K p ] in the first receiver module;
decrypting the second encrypted version of the pairing key E S 2 [K p ] in the second receiver module;
decrypting an encrypted version of the control word E[CW] in the second receiver module;
re-encrypting the decrypted control word CW according to the decrypted second encrypted version of the pairing key;
providing the re-encrypted control word E K p [CW] from the second receiver module to the first receiver module; and
decrypting the re-encrypted control word E K p [CW] using the decrypted first encrypted version of the pairing key K p .
4. The method of claim 1 , further comprising the steps of:
transmitting a second media service enabling request for a second media service from the broadcasters to the broker, the second media service enabling request comprising an identification of the receiver;
receiving a first encrypted version of a second pairing key E S 1 [K p 2 ] from the broker, the first encrypted version of the second pairing key E S 1 [K p 2 ] decryptable by the first information S 1 securely stored in the first receiver module of the receiver;
generating a second encrypted version of the second pairing key E S 2 [K p 2 ], the second encrypted version of the pairing key E S 2 [K p 2 ] decryptable by the second information S 2 securely stored in the second receiver module; and
transmitting the first encrypted version of the second pairing key E S 1 [K p 2 ] and the second encrypted version of the second pairing key E S 2 [K p 2 ] to the receiver;
wherein the second media service is different than the first media service.
5. The method of claim 4 , wherein the media program is encrypted according to a control word CW and the method further comprises the steps of:
decrypting the first encrypted version of the second pairing key E S 1 [K p 2 ] in the first receiver module;
decrypting the second encrypted version of the second pairing key E S 2 [K p 2 ] in the second receiver module;
decrypting an encrypted version of the control word E[CW] in the second receiver module;
re-encrypting the decrypted control word CW according to the decrypted second encrypted version of the second pairing key K p 2 ;
providing the re-encrypted control word
E
K
P
2
[
CW
]
from the second receiver module to the first receiver module; and
decrypting the re-encrypted control word
E
K
P
2
[
CW
]
using the decrypted first encrypted version of the second pairing key K p 2 .
6. The method of claim 2 , further comprising the steps of:
transmitting a second media service enabling request for a second service from a second broadcaster of the plurality of broadcasters to the broker, the request comprising the identification of the receiver;
receiving a first encrypted version of a second pairing key E S 1 [K p 2 ] from the broker, the first encrypted version of the second pairing key E S 1 [K p 2 ] decryptable by the first information S 1 securely stored in the first receiver module of the receiver;
generating a second encrypted version of the second pairing key E S 2 [K p 2 ], the second encrypted version of the pairing key E S 2 [K p 2 ] decryptable by the second information S 2 securely stored in the second receiver module; and
transmitting the first encrypted version of the second pairing key E S 1 [K p 2 ] and the second encrypted version of the second pairing key E S 2 [K p 2 ] to the receiver;
wherein the second media service is selected from the group consisting of:
a general broadcast service from the second broadcaster, including access to a number of media channels as a baseline fee service;
a particular media program from the second broadcaster, including an order ahead pay per view service and an impulse pay per view service; and
a particular set of media programs from the second broadcaster.
7. The method of claim 6 , wherein the media service is encrypted according to a CW, and the method further comprises the steps of:
decrypting the first encrypted version of the second pairing key E S 1 [K p 2 ] in the first receiver module;
decrypting the second encrypted version of the second pairing key E S 2 [K p 2 ] in the second receiver module;
decrypting the an encrypted version of the control word E[CW] in the second receiver module;
re-encrypting the decrypted control word CW according to the decrypted second encrypted version of the second pairing key K p 2 ;
providing the re-encrypted control word
E
K
P
2
[
CW
]
from the second receiver module to the first receiver module; and
decrypting the re-encrypted control word
E
K
P
2
[
CW
]
using the decrypted first encrypted version of the second pairing key K p 2 .
8. The method of claim 1 , wherein the first media service enabling request is transmitted in response to a media service request, the media service request transmitted from the receiver to the broadcaster.
9. The method of claim 1 , wherein the first information S 1 and the second information S 2 is known to the broker and the broadcasters.
10. The method of claim 1 , wherein the first information S 1 is known to the broker and unknown to the broadcaster, and wherein the second information S 2 is known to the broadcaster and unknown to the broker.
11. The method of claim 1 , wherein:
the first information S 1 is a first secret unique to the receiver and stored in a first module of the receiver;
the second information S 2 is a second secret is securely stored in a second module of the receiver.
12. The method of claim 11 , wherein the second module is a smart card removably coupleable to the first module.
13. The method of claim 11 , wherein the second module is irremovably integrated with the receiver.
14. The method of claim 1 , wherein the pairing key is generated by the broadcaster and transmitted to the broker.
15. The method of claim 1 , wherein the pairing key is generated by the broker and transmitted to the broadcaster in response to the service enabling request.
16. A system for brokering the enabling of communication of encrypted at least one encrypted media service of a group of encrypted media services from a plurality of broadcasters to a plurality of receivers, the at least one encrypted media service decryptable by a first receiver module securely communicating with a second receiver module according to a pairing key K p associated with a receiver of the plurality of receivers, the system comprising:
a broker, for providing a first encrypted version of the pairing key E S 1 [K p ] in response to a media service enabling request for a media service from a broadcaster of the plurality of broadcasters, the media service request having an identification of the receiver; and
wherein the first encrypted version of the pairing key E S 1 [K p ] is decryptable by first information S 1 stored in the first receiver module and wherein the first receiver module receives the first encrypted version E S 1 [K p ] of the pairing key K p and a second encrypted version of the pairing key E S 2 [K p ] from the broadcaster, the second encrypted version of the pairing key E S 2 [K p ] being generated by the broadcaster by encrypting the pairing key with second information S 2 and being decryptable by second information S 2 stored in the second receiver module;
wherein each media service in the group is enabled by a different pairing key K p .
17. The system of claim 16 , wherein the media service is selected from a group consisting of:
a general broadcast service from the broadcaster, including access to a number of media channels as a baseline fee service;
a particular media program from the broadcaster; and
a particular set of media programs from the broadcaster.
18. The system of claim 17 , wherein the first information S 1 and the second information S 2 is known to the broker and the broadcaster.
19. The system of claim 17 , wherein the first information S 1 is known to the broker and unknown to the broadcaster, and wherein the second information S 2 is known to the broadcaster and unknown to the broker.
20. The system of claim 17 , wherein:
the first information S 1 is a first secret unique to the receiver and is securely stored in first module of the receiver; and
wherein the second information S 2 is a second secret securely stored in second module of the receiver.
21. The system of claim 17 , wherein the pairing key is generated by the broadcaster and transmitted to the broker.
22. The system of claim 17 , wherein the pairing key is generated by the broker and transmitted to the broadcaster in response to the media service enabling request.
23. An apparatus for brokering the enabling of communication of at least one encrypted media service of a group of encrypted media services from a plurality of broadcasters to a plurality of receivers, the at least one encrypted media service decryptable by a first receiver module securely communicating with a second receiver module according to a pairing key associated with a receiver of the plurality of receivers, comprising:
means for transmitting a first media service enabling request for a first media service from a broadcaster of the plurality of broadcasters to a broker independent from the broadcaster, the first media service enabling request comprising an identification of the receiver;
means for receiving a first encrypted version of the pairing key E S 1 [K p ] in the broadcaster from the broker, the first encrypted version of the pairing key E S 1 [K p ] decryptable by first information S 1 securely stored in the first receiver module of the receiver;
means for encrypting the pairing key with second information S 2 to generate a second encrypted version of the pairing key E S 2 [K p ] in the broadcaster, the second encrypted version of the pairing key E S 2 [K p ] decryptable by the second information S 2 securely stored in the second receiver module; and
means for transmitting the first encrypted version of the pairing key E S 1 [K p ] and the second encrypted version of the pairing key E S 2 [K p ] to the receiver;
wherein each media service in the group is enabled by a different pairing key K p .
24. The apparatus of claim 23 , wherein the media service is selected from a group consisting of:
a general broadcast service from the broadcasters, including access to a number of media channels as a baseline fee service;
a particular media program from the broadcaster; and
a particular set of media programs from the broadcaster.