05319705 is referenced by 707 patents and cites 8 patents.

A method and system are disclosed for securely distributing a plurality of software files from a software distribution processor to a user processor, while selectively enabling the user processor to only use a subset of a lesser plurality of the software files. This is achieved by employing a customer key which includes a clear customer number and a derived portion derived from the customer number. The customer key is transformed into a second customer key which serves as a key expression for encrypting a file encryption key specifically intended for a respective one of the plurality of files. A plurality of software files can be stored together, for example on a CD-ROM, with each file encrypted under a corresponding file encryption key. The CD-ROM can be distributed to many user processors. When a specific user processor needs to run one of the software files, a request will be transmitted from the user processor to the software distribution processor. In response to that request, an encrypted file encryption key specific for the requested file, will be transmitted to the user processor. This will enable the user processor to decrypt only the requested file from the CD-ROM. All other files on the CD-ROM remain in their encrypted form and cannot be decrypted and used by the file encryption key received from the software distribution processor.

Title
Method and system for multimedia access control enablement
Application Number
7/964324
Publication Number
5319705
Application Date
October 21, 1992
Publication Date
June 7, 1994
Inventor
John D Wilkins
Somerville
VA, US
James D Randall
Herndon
VA, US
Rostislaw Prymak deceased
late of Dumfries
VA, US
Stephen M Matyas
Manassas
VA, US
An V Le
Manassas
VA, US
Donald B Johnson
Manassas
VA, US
Alphonse M Bracco
Reston
VA, US
Bernard J Halter
Longmont
CO, US
Agent
John E Hoel
Assignee
International Business Machines Corporation
NY, US
IPC
H04L 9/00
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