Authentication system for digital cellular communications

Patent 5091942 Issued on February 25, 1992. Estimated Expiration Date:

July 23, 2010. 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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Inventor

Dent, Paul

Application

No. 556890 filed on 07/23/1990

US Classes:

380/46, Nonlinear (e.g., pseudorandom)380/44, Having particular key generator455/411Privacy, lock-out, or authentication

Examiners

Primary: Tarcza, Thomas H.
Assistant: Swann, Tod R.

Attorney, Agent or Firm

Johnson & Gibbs

International Class

H04L 009/02

Abstract

A system for the authentication of mobile stations and base stations in a cellular communications network. The system includes an algorithm which generates not only a key dependent response to a random challenge, but also a temporary conversation key or call variable which may be used to encipher traffic in the network. To protect against clones in the network, the algorithm uses a rolling key which contains historical information. A bilateral authentication procedure may be used to update the rolling key and to generate a new conversation key.