Patents by Inventor Claus P. Schnorr

Claus P. Schnorr 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: 4995082
    Abstract: In a data exchange system working with processor chip cards, a chip card transmits coded identification data I, v and, proceeding from a random, discrete logarithm r, an exponential value x=2.sup.r (mod p) to the subscriber who, in turn, generates and transmits a random bit sequence e to the chip card. By multiplication of a stored, private key s with the bit sequence e and by addition of the random number r, the chip card calculates a y value and transmits the y value to the subscriber who, in turn, calculates an x value from the information y, v.sub.j and e and checks whether the calculated x value coincides with the transmitted x value. For an electronic signature, a hash value e is first calculated from an x value and from the message m to be signed and a y value is subsequently calculated from the information r, s.sub.j and e. The numbers x and y then yield the electronic signature of the message m.
    Type: Grant
    Filed: February 23, 1990
    Date of Patent: February 19, 1991
    Inventor: Claus P. Schnorr