Patents by Inventor Wai F. Choi

Wai F. Choi 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).

  • Automatic root key rollover during digital signature verification
    Patent number: 10057067
    Abstract: A method for verifying digital signatures in the presence of root key rollover includes issuing a cross-certificate to a rekeyed root certificate, validating the cross-certificate and the rekeyed root certificate with respect to an original trusted root certificate, and validating a digital media signature using the cross-certificate and the rekeyed root certificate. The method may also include adding the rekeyed root certificate to an end user's trusted root certificate store. The digital media signature validated via the method may correspond to a program signature. Validating the cross-certificate and the rekeyed root certificate may include verifying certificates within a program's certificate chain. A computer program product and a computer system corresponding to the method are also disclosed.
    Type: Grant
    Filed: May 27, 2015
    Date of Patent: August 21, 2018
    Assignee: International Business Machines Corporation
    Inventors: Wai F. Choi, James W. Sweeny
  • AUTOMATIC ROOT KEY ROLLOVER DURING DIGITAL SIGNATURE VERIFICATION
    Publication number: 20160352521
    Abstract: A method for verifying digital signatures in the presence of root key rollover includes issuing a cross-certificate to a rekeyed root certificate, validating the cross-certificate and the rekeyed root certificate with respect to an original trusted root certificate, and validating a digital media signature using the cross-certificate and the rekeyed root certificate. The method may also include adding the rekeyed root certificate to an end user's trusted root certificate store. The digital media signature validated via the method may correspond to a program signature. Validating the cross-certificate and the rekeyed root certificate may include verifying certificates within a program's certificate chain. A computer program product and a computer system corresponding to the method are also disclosed.
    Type: Application
    Filed: May 27, 2015
    Publication date: December 1, 2016
    Inventors: Wai F. Choi, James W. Sweeny