System and method for enhanced piracy protection in a wireless personal communication device
First Claim
1. A method of controlling content usage in a personal communication device using a decryption key that is divided into a plurality of key-shares, the method comprises:
- providing the personal communication device a first key-share in response to a request for content; and
verifying credit of a user of the personal communication device;
providing the personal communication device a second key-share when the credit is confirmed; and
combining the first and second key-shares with a third key share stored in the personal communication device for use in decrypting content.
4 Assignments
0 Petitions
Accused Products
Abstract
A key-sharing scheme is used to control distribution and use of video and audio content in personal digital assistants (PDAs) and other wireless devices. A private key is split into key-shares using a Blakley-Shamir key splitting technique and the key-shares are distributed to various network entities including a finance server and security server. Key-shares are also stored in a user'"'"'s subscriber identity module (SIM) and a security processor of the PDA. The key-shares from the network entities are provided to the PDA after the user requests specific video or audio content and a credit verification is performed. The PDA'"'"'s security processor combines the key-shares to form the decryption key for use in playing the content by the PDA'"'"'s communications processor. When a service limit is reached, the PDA'"'"'s security processor purges the key-shares to prevent further use of the content.
138 Citations
23 Claims
-
1. A method of controlling content usage in a personal communication device using a decryption key that is divided into a plurality of key-shares, the method comprises:
-
providing the personal communication device a first key-share in response to a request for content; and
verifying credit of a user of the personal communication device;
providing the personal communication device a second key-share when the credit is confirmed; and
combining the first and second key-shares with a third key share stored in the personal communication device for use in decrypting content. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15)
-
-
16. A processing system for use in a personal communication device, the processing system comprising:
-
a security processor portion to combine a plurality of key-shares and decrypt content for the processing system, the security processor portion including a monitor for usage of the content constructed and arranged to purge at least one of the key-shares when the usage exceeds a measurement parameter; and
a communications processor portion to receive decrypted content from the security processor portion and providing decrypted content for playing on the personal communication device. - View Dependent Claims (17, 18, 19, 20)
-
-
21. A personal communication device comprising:
-
a processor area to store first key-share therein;
a module receiving area to receive a subscriber identity module (SIM), the SIM having a second-key share stored therein; and
an RF interface to receive a third key-share and encrypted content over a wireless communication link, wherein the processor area includes apparatus constructed and arranged to combine the first, second and third key-shares to decrypt the encrypted content and monitor playing of the decrypted content against measurement parameters. - View Dependent Claims (22, 23)
-
Specification