Encryption synchronization combined with encryption key identification

Patent 5185796 Issued on February 9, 1993. Estimated Expiration Date:

May 30, 2011. 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

Patent References

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Inventor

Wilson, Alan L.

Assignee

Motorola, Inc.

Application

No. 707487 filed on 05/30/1991

US Classes:

380/277, KEY MANAGEMENT380/273, Rekeying system510/255, With corrosion inhibiting or solvent stabilizing component510/256, With halogenated hydrocarbon, abrasive, coating, or polishing component510/258, With corrosion or embrittlement inhibiting or solvent stabilizing component (e.g., pickling bath, etc.)510/264, Organic nitrogen containing substituent in the component510/273, Halogenated hydrocarbon component (e.g., degreasing composition, etc.)510/411Oxygen containing component

Examiners

Primary: Cangialosi, Salvatore

Attorney, Agent or Firm

Parmelee; Steven G., Lukasik; Susan L.

International Class

H04L 009/00

Abstract

In an encrypted radio system, transmsitters and receivers can each be provided with a plurality of encryption algorithms (407 and 425) and/or encryption key variables (408 and 426). A unique logical ID (409 and 427) corresponds to each of the above. During transmission of an encrypted message, both encryption synchronization information (319) and information concerning the logical ID (318) is repetitively interleaved with the encrypted message itself. So configured, a receiver that temporarily loses viable reception can again obtain encryption synchronization and algorithm/key information, and therefore rapidly recover from the reception disturbance.