Verification of the source of program information in a conditional access system

Patent 6105134 Issued on August 15, 2000. Estimated Expiration Date:

July 31, 2018. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

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Inventors

Assignee

Scientific-Atlanta, Inc.

Application

No. 126795 filed on 07/31/1998

US Classes:

713/170, Authentication of an entity and a message380/239, Encrypted code control signal380/241, Having program ID or authorization380/279, Key distribution center713/168Particular communication authentication technique

Examiners

Primary: Barron, Gilberto Jr.

Attorney, Agent or Firm

Barnhardt, II; Hubert J., Massaroni; Kenneth M., Gardner; Kelly A.

Foreign Patent References

752786 EP. 01/13/1997

International Classes

H04L 009/32
H04N 007/167

Abstract

A cable television system provides conditional access to services. The cable television system includes a headend from which service "instances", or programs, are broadcast and a plurality of set top units for receiving the instances and selectively decrypting the instances for display to system subscribers. The service instances are encrypted using public and/or private keys provided by service providers or central authorization agents. Keys used by the set tops for selective decryption may also be public or private in nature, and such keys may be reassigned at different times to provide a cable television system in which piracy concerns are minimized.