05625693 is referenced by 185 patents and cites 20 patents.

An executable interactive program is combined with audio/video data for transmission. The program is divided into modules, similar to computer files, and a Directory Module is created which links program modules. Security for the executable application is provided by attaching a signed certificate to respective Directory Modules. The integrity of respective modules is monitored by hashing respective modules and including respective hash values in the Directory Module. A hash value of the Directory Module containing the other hash values is generated, encrypted and attached to the Directory Module. At a receiver the certificate is decoded and checked for authenticity of provider. If the certificate is authentic the program may be executed but only if receiver generated hash values of respective program modules are identical to corresponding hash values contained in the Directory Module.

Title
Apparatus and method for authenticating transmitting applications in an interactive TV system
Application Number
8/499280
Publication Number
5625693
Application Date
July 7, 1995
Publication Date
April 29, 1997
Inventor
Vincent Dureau
Vemas
CA, US
Pankaj Rohatgi
Sunnyvale
CA, US
Agent
Ronald H Kurdyla
Eric P Herrmann
Joseph S Tripoli
Assignee
Thomson Consumer Electronics
IN, US
IPC
H04N 7/16
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