05249230 is referenced by 158 patents and cites 7 patents.

An environment which includes a communications network, user terminals, and an authentication center provides communication services only to legitimate subscribers. The center receives an equipment ID for each terminal and uses a secret key to encrypt the equipment ID with a user ID and an error detection code to form an encrypted block. This block is programmed into an authentication module and sent to the subscriber for installation in the subscriber's terminal. The center sends a public key to authentication nodes of the network. When the subscriber operates the terminal to gain access to the network, a log-on message, which includes the encrypted block and an unencrypted version of the equipment ID, is sent to an authentication node. The authentication node decrypts the encrypted block and evaluates the IDs to determine whether to grant access to services offered by the network.

Title
Authentication system
Application Number
7/795606
Publication Number
5249230
Application Date
November 21, 1991
Publication Date
September 28, 1993
Inventor
Thomas J Mihm Jr
Mesa
AZ, US
Agent
Robert M Handy
Assignee
Motorola
IL, US
IPC
H04K 1/00
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