Patent · US Expired

Data processing with a key

US7529369B2 · kind B2 · utility

2Cited by
7References
12Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 20, 2001
Grant dateMay 5, 2009
Priority date
Expiry dateNov 23, 2022

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L9/14
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

In a data processing device, a first key is produced based on a secret key so that the latter is never used in a clear form. In a preliminary step, the secret key and a random number are applied to a function producing a first key. The first key and the random number are pre-stored in the device. For each data processing, the first key and another random number are applied to another function to produce a second key, and the second key and the stored number are applied as inverse of the function to produce a third key used for processing the data. The device can be a smart card and the data the confidential code presented to the card.

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