Patent · US Expired

Encipher method and decipher method

US4982429A · kind A · utility

20Cited by
1References
41Claims
0Family size

Assignees

Inventors

Key dates

Filing dateApr 27, 1989
Grant dateJan 1, 1991
Priority date
Expiry dateApr 27, 2009

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L9/0625
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

There are provided an encipher method of enciphering message data made by a microcomputer or the like at a high speed by using encipher keys which have previously been stored in a smart card or the like and a decipher method of deciphering the ciphertext made by the encipher method at a high speed by using the encipher keys. The encipher method and the decipher method are suitable for, particularly, a 32-bit microcomputer and include a process expressed by the function Rot.sub.2 i(x) (i=2, 3, 4) in each process. Rot.sub.2 i(x) is the process to circular shift a data train x of 32 bits to the left or right by 2.sup.i bits (i=2, 3, 4).

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