Pad encryption method and software
AssigneeSCM Microsystems GmbH
InventorJoseph C. Angert
Life of this patent
Estimating the term…
Abstract
A pad encryption software architecture includes space on a floppy for storing the pad to be used with the encryption software. The pad is XOR generated with random numbers subject to redetermined offsets. If the pad is smaller than the text to be encrypted, then XOR takes several cycles with redetermined offsets used in XORing the pad with the remaining plain text to be encrypted. The offset is determined from a user selected password. New offsets are determined from old offsets by adding the current offset to the value of the byte in the pad located at the offset value.
Claims24
A method of encryption of a sequence of plaintext characters, the method comprising:
- receiving, at a computer, a first sequence of K numbers p(k), numbered k=1, 2, . . . , K, where K is a selected integer ≧2, with each number p(k) corresponding to a plaintext character in an ordered sequence of K characters;
- receiving a second sequence of M+1 pseudorandom numbers r(m), numbered m=0, 1, 2, . . . M, where M is a selected integer ≧2;
- receiving a third sequence of N selected non-negative offset numbers o(n), numbered n=1, 2, . . . , N, where N is a selected integer ≧2;
- for each plaintext number p(k) and corresponding index k, causing the computer to provide an offset pseudorandom sequence of numbers ro(k) in the second sequence, where the offset random number ro(k) is offset from the preceding offset random number ro(k−1) by the offset number o(k);
- and
- forming an ordered sequence of ciphertext numbers c(k), where c(k) is a selected logical combination of p(k) and ro(k).
A system for encryption of plaintext characters, the system comprising a computer that is programmed:
- to receive a first sequence of K numbers p(k), numbered k=1, 2, . . . , K, where K is a selected integer ≧2, with each number p(k) corresponding to a plaintext character in an ordered sequence of K characters;
- to receive a second sequence of M+1 pseudorandom numbers r(m), numbered m=0, 1, 2, . . . M, where M is a selected integer ≧2;
- to receive a third sequence of N selected non-negative offset numbers o(n), numbered n=1, 2, . . . , N, where N is a selected integer ≧2;
- for each plaintext number p(k) and corresponding index k, to provide an offset pseudorandom sequence of numbers ro(k) in the second sequence, where the offset random number ro(k) is offset from the preceding offset random number ro(k−1) by the offset number o(k);
- and
- to form an ordered sequence of ciphertext numbers c(k), where c(k) is a selected logical combination of p(k) and ro(k).
Dependencies are inferred from the claim text.