Showing papers on "Cipher published in 1973"

Variant key matrix cipher system

Abstract: This is a cipher system for enciphering a stream of binary data by means of a product cipher. A clear message represented in a binary data format is transformed into a cipher message by operating on each bit of clear information with a complex modulo-two addition function. This function is dependent on previous internal cipher digits transmitted and varies for each message bit processed. The function is developed by continually shifting a key matrix under the control of a varying control matrix. The control matrix is formed from the sub-product of the complex function developed in generating each cipher bit.

A homophonic cipher for computational cryptography

Abstract: Computational cryptography deals with the storage and processing of sensitive information in computer systems by enciphering. Sensitive information is information that for one reason or another must be protected from being disclosed to individuals without proper authorization. The need for systems to be secure from unauthorized access to sensitive information has been well documented. Cyrptographic techniques appear to be one of the most simple and secure methods of providing this much needed protection.

Addendum to a multiple-precision division algorithm

Abstract: In [1] Mifsud presented a generalized division algorithm for positive integral operands. The uniqueness of the method was advertised as causing each trial cipher in the quotient to be either equal to or one greater than its final replacement. The method of describing the algorithm was intended to stress the simple mathematical facts that were the basis of the algorithm. However, some difficulty arises with the programming and implementation of the algorithm. Article [1] addressed itself to the calculation of the trial cipher by using the first two digits of the partial dividend (step 6); i.e. it formed [pr+1pr/dr], with pr+1