Patents Represented by Attorney Charles Rowe
  • Patent number: 6130946
    Abstract: The cryptographic system automatically and continuously changes the cipher equivalents representing plaintext characters so as to prevent any periodicity in the relationship. The system has a series of juxtaposed, rotatable, connection changing mechanisms to provide a large number of alternative paths for the passage of an electric current corresponding to a message character. Further, the system has parts for the irregular and permutative displacements of the members of a set of circuit changing mechanisms to thwart cryptanalysis. The juxtaposed cipher commutators are controlled by cam wheels of different diameters.
    Type: Grant
    Filed: October 23, 1936
    Date of Patent: October 10, 2000
    Assignee: The United States of America as represented by the National Security Agency
    Inventor: William F. Friedman