06851055 is referenced by 113 patents and cites 6 patents.

A digital video recorder (DVR) is disclosed for storing a plaintext video program as an encrypted video program. The DVR comprises a random access storage (RAS) device for storing the encrypted video program in encrypted segments. The DVR further comprises a cryptography facility comprising an encoder for encrypting plaintext segments of the plaintext video program into the encrypted segments stored on the RAS device, and a decoder for randomly and independently decrypting the encrypted segments of the encrypted video program into plaintext segments during playback.

Title
Digital video recorder for encrypting/decrypting video programs in segments to facilitate trick play features
Application Number
9/676637
Publication Number
6851055 (B1)
Application Date
September 30, 2000
Publication Date
February 1, 2005
Inventor
Alan P Rice
Santa Ana
CA, US
William B Boyle
Lake Forest
CA, US
Agent
Howard H Sheerin Esq
Milad G Shara Esq
Assignee
Keen Personal Media
CA, US
Keen Personal Technologies
CA, US
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