06550011 is referenced by 406 patents.

A system and method for providing protection of content which may be transmitted over unsecure channels, including storage and transmission in bulk media, transmission over a network such as the Internet, transmission between components of an open system, and broadcast transmitted, to compliant storage devices and/or compliant use devices is disclosed. The technique for providing protection from unauthorized utilization of the content so stored is provided publicly in order to allow for those utilizing a conforming media device to master or generate content protected according to the present invention. According to a preferred embodiment, public key cryptography is utilized to identify compliant devices and to transmit cryptographic keys protecting content data. In the preferred embodiment content is protected using private key cryptography to optimize system performance.

Title
Media content protection utilizing public key cryptography
Application Number
9/414213
Publication Number
6550011 (B1)
Application Date
October 7, 1999
Publication Date
April 15, 2003
Inventor
J Robert Sims III
Fort Collins
CO, US
Assignee
Hewlett Packard Development Company
TX, US
IPC
H04L 12/22
View Original Source