04578531 is referenced by 101 patents and cites 8 patents.

Encryption systems typically rely on the distribution of cipher keys between terminals for scrambling and unscrambling transmitted messages. Elaborate security precautions are necessary to protect the cipher keys since a compromise of the key could result in a compromise of the transmission. There is disclosed a key distribution method and apparatus which uses a channel from identified terminals to a central key distribution center for the establishment, on a one-session basis, of the key which is to be used for the next session between those terminals. The key establishing link is itself encoded using a cipher key which changes after each usage. Provision is made to verify, for each new connection, that a compromise has not priorly occurred.

Title
Encryption system key distribution method and apparatus
Application Number
6/386805
Publication Number
4578531
Application Date
June 9, 1982
Publication Date
March 25, 1986
Inventor
Jeffrey G Osborn
Old Bridge
NJ, US
Joseph R Everhart
Holmdel
NJ, US
Agent
David H Tannenbaum
Assignee
AT&T Bell Laboratories
NJ, US
IPC
H04K 1/02
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