Patents by Inventor Stephen C. Pohlig

Stephen C. Pohlig has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4424414
    Abstract: A cryptographic system transmits a computationally secure cryptogram that is generated from a secret transformation of the message sent by the authorized transmitter; the cryptogram is again transformed by the authorized receiver using a secret reciprocal transformation to reproduce the message sent. The secret transformations use secret cipher keys that are known only by the authorized transmitter and receiver. The transformations are performed with nonsecret operations, exponentiation, that are easily performed but extremely difficult to invert. It is computationally infeasible for an eavesdropper either to solve known plaintext-ciphertext pairs for the secret cipher keys, or to invert the nonsecret operations that are used to generate the cryptogram.
    Type: Grant
    Filed: May 1, 1978
    Date of Patent: January 3, 1984
    Assignee: Board of Trustees of the Leland Stanford Junior University
    Inventors: Martin E. Hellman, Stephen C. Pohlig