Patent · US Expired

Method and apparatus for data encryption

US5003597A · kind A · utility

170Cited by
4References
27Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 21, 1989
Grant dateMar 26, 1991
Priority date
Expiry dateDec 21, 2009

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L2209/08
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

A method and apparatus for encrypting and decrypting data which operates efficiently on computers of differing architectures is disclosed. Unlike previous encryption/decryption method and apparatus, the present invention executes efficiently in the computer's software. The method uses part of the data input to access a table of pseudo-random numbers. The pseudo-random numbers are exclusively ORed (XORed) with the remaining part of the data input. The output from the XOR operation is then used to access the table where the other portion of the data is in turn XORed with the pseudo random numbers. This iterative process continues until the data is fully randomized. Several variations of this method are presented.

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