Patents by Inventor Jack Schifando

Jack Schifando 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).

  • PIN verification using cipher block chaining
    Publication number: 20050149739
    Abstract: A PIN verification apparatus comprises a plurality of cipher blocks linked in a Cipher Block Chain (CBC) and keyed with a secret PIN Verification Key (PVK). A first input block is coupled to a first cipher block in the CBC chain and is configured to receive a plaintext block derived from a secret PIN. A second input block is coupled to a second cipher block in the CBC chain capable of receiving a plaintext block derived from a non-secret entity-identifier and ciphertext from a cipher block in the CBC chain.
    Type: Application
    Filed: December 31, 2003
    Publication date: July 7, 2005
    Applicant: Hewlett-Packard Development Company, L.P.
    Inventors: W. Hopkins, Steven Wierenga, Ching-Hsuan Chen, Jack Schifando