Patent · US Expired

Technique for compressing digital certificates for use in smart cards

US6564319B1 · kind B1 · utility

7Cited by
10References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 29, 1997
Grant dateMay 13, 2003
Priority date
Expiry dateApr 24, 2018

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03M7/30
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

A technique for compressing certificate information for use in portable credit instruments having limited storage capacity. An end user certificate typically actually comprises a chain of certificates, as SET transactions require not only the end user certificate and its parent certificates. Each certificate in the certificate chain is compared to a template for that certificate, and the differences are stored. Redundant differences within each certificate are deleted, as are differences which may be derived from differences stored for other certificates in the certificate chain. The remaining stored differences are then recorded on an end user credit instrument, such as a smart card. Preferably, the certificate chain is then recreated for verification purposes before the card is issued. PER encoding may also be employed to further compress the certificate information to be recorded on the credit instrument.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.