Patent · US Expired

32N +D bit key encryption-decryption system using chaos

US5751811A · kind A · utility

103Cited by
10References
37Claims
0Family size

Inventors

Key dates

Filing dateNov 26, 1996
Grant dateMay 12, 1998
Priority date
Expiry dateNov 26, 2016

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L9/0662
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

A cryptographic method and system based on chaos theory is provided. Unique random 64-bit binary strings generated from an iterative chaotic equation are used as logic and arithmetic operands during encryption/decryption. The random 64-bit binary strings are generated based on 4 initializer values that produce thousands of iterated values from the chaotic equation z.sub.t+1 =Z.sub.t.sup.2 +c, where z and c are complex numbers. The 64-bit random numbers are translated into two 32-bit keys so that each 32 bits of message are encrypted/decrypted, using a bitwise logic operator such as an exclusive-or, with a unique 32-bit key for the length of the message file. For additional security, a combination of logic and arithmetic operators are used on the 32-bit keys and the 32-bit blocks of message text to produce 32N-bit blocks of ciphertext, where N=2.sub.r and r.ltoreq.2. For any set of 4 initializer values, the lifetime, n, is the number of iterations of the equation Z.sub.t+1 =z.sub.t.sup.2 +c before divergence of the output to infinity, and the number of unique 32-bit keys is 4n, where n can be over 300,000 for a multitude of initializer values.

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