Patents by Inventor Chan-fung Chong

Chan-fung Chong 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).

  • Publication number: 20050235140
    Abstract: A method and system for long term electronic document archiving. The system collects a certificate revocation information for a certificate from a certificate authority that indicates the validity of the certificate used in an electronic document. The certificates are collected from a certificate authority. The system then generates at least two layers of signature and timestamp from the electronic document, certificate revocation information collected, and the collected certificate. Cryptographic primitives of different strength are used, and the two layers of signature and timestamp generated have different cryptographic strengths. The signature is generated using a system signing key whereas the timestamp is generated by an external entity. A digital aging token is then formed by combining the original electronic document, certificate revocation information, and certificate collected to the layers generated.
    Type: Application
    Filed: March 11, 2005
    Publication date: October 20, 2005
    Inventors: Chi-kwong Hui, Kam-pui Chow, Chan-fung Chong, Kwok-hung Pun, Wai-wan Tsang, Hak-wai Chan, Kin-ying Yu