Patent · US Expired

Encryption apparatus and methods for raising a large unsigned integer to a large unsigned integer power modulo a large unsigned integer

US4658094A · kind A · utility

37Cited by
3References
18Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 28, 1985
Grant dateApr 14, 1987
Priority date
Expiry dateMar 28, 2005

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L2209/122
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

There is disclosed an encryption apparatus which apparatus functions to raise a large unsigned integer (B) indicative of message data to a large unsigned integer power E, modulo a large unsigned integer M with each of said integers being as large as N bits wherein the resulting large unsigned integer C is adapted for transmission over an insecure communications channel. The apparatus may likewise operate on a received integer C to recover the decrypted message B. The circuitry includes first logic means which is responsive to the large unsigned integer (B) for successively squaring said integer including means for reducing said squared integers successively by a given modulus M to provide at an output a first value indicative of said squared integer as reduced by said given modulus, selectively operated gating means are coupled to said first logic means and operates to receive bits of a given exponent power E. The gating means applies selected bits of the exponent power to second logic means which are controlled by said gating means to provide the product of said first value as further modified by modulus means for providing at its output the large unsigned integer for transmission…

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