Patents by Inventor Louis Bryant Tuckerman, III

Louis Bryant Tuckerman, III 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: 4078152
    Abstract: A Block-Cipher Cryptographic System utilizing a unique user supplied key to control the cryptographic function and including means for modifying an input data block prior to performing a key-controlled transformation operation thereon. Said means includes means for extracting a segment of data utilized in a prior cryptographic transformation of the system and combining said segment with the input data block. The means for combining comprises a transformation which is a discrete valued function which in the preferred embodiment is an exclusive-or. In the preferred embodiment of the invention a block of ciphertext data is combined with the just succeeding input data block by an exclusive-or operation prior to the key-controlled transformation operation which produces said ciphertext blocks.
    Type: Grant
    Filed: April 26, 1976
    Date of Patent: March 7, 1978
    Assignee: International Business Machines Corporation
    Inventor: Louis Bryant Tuckerman, III