Patent · US Expired

Cryptographic communications system and method

US4405829A · kind A · utility

1,432Cited by
1References
40Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 14, 1977
Grant dateSep 20, 1983
Priority date
Expiry dateDec 14, 1997

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F2211/007
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A cryptographic communications system and method. The system includes a communications channel coupled to at least one terminal having an encoding device and to at least one terminal having a decoding device. A message-to-be-transferred is enciphered to ciphertext at the encoding terminal by first encoding the message as a number M in a predetermined set, and then raising that number to a first predetermined power (associated with the intended receiver) and finally computing the remainder, or residue, C, when the exponentiated number is divided by the product of two predetermined prime numbers (associated with the intended receiver). The residue C is the ciphertext. The ciphertext is deciphered to the original message at the decoding terminal in a similar manner by raising the ciphertext to a second predetermined power (associated with the intended receiver), and then computing the residue, M', when the exponentiated ciphertext is divided by the product of the two predetermined prime numbers associated with the intended receiver. The residue M' corresponds to the original encoded message M.

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