04218582 is referenced by 520 patents.

A cryptographic system transmits a computationally secure cryptogram that is generated from a publicly known transformation of the message sent by the transmitter; the cryptogram is again transformed by the authorized receiver using a secret reciprocal transformation to reproduce the message sent. The authorized receiver's transformation is known only by the authorized receiver and is used to generate the transmitter's transformation that is made publicly known. The publicly known transformation uses operations that are easily performed but extremely difficult to invert. It is infeasible for an unauthorized receiver to invert the publicly known transformation or duplicate the authorized receiver's secret transformation to obtain the message sent.

Title
Public key cryptographic apparatus and method
Application Number
5/839939
Publication Number
4218582
Application Date
October 6, 1977
Publication Date
August 19, 1980
Inventor
Ralph C Merkle
Palo Alto
CA, US
Martin E Hellman
Stanford
CA, US
Assignee
The Board of Trustees of the Leland Stanford Junior University
CA, US
IPC
H04L 9/04
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