US4195196A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Variant key matrix cipher system
Assignee: International Business Machines Corp
•
Filing: 1973-10-15
•
Granted: 1980-03-25
•
Expires: 1993-10-15
Abstract
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.
Inventors
- 👤 Horst Feistel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 10:15
CPC Classifications
H; H04; H04L; H04L9/00; H04L9/06; H04L9/065; H04L2209/00; H04L2209/08; H04L2209/12; H04L2209/125
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
145 words
A variant key cryptographic system comprising: input means for introducing a plurality of electrical signals in binary form as message information to be enciphered or deciphered; priming means for presenting a plurality of random binary signals to said input means to initialize the system prior to introducing message information thereto, matrix storage means for arranging a cipher key in an n×m matrix array, wherein m and n are greater than 1; a plurality of modulo-two adders interconnected with each other for adding selected elements from said matrix with binary signals obtained from said input means; feedback means connected to said plurality of modulo-two adders; non-affine transformation means connected to said feedback means for transforming the feedback signals present on the lines contained in said feedback means; shift control means connected to said non-affine transformation means for rearranging selected matrix elements within said n×m matrix array.
Claim 2
Dependent Claim
145 words
A variant key cryptographic system comprising: input means for introducing a plurality of electrical signals in binary form as message information to be enciphered or deciphered; priming means for presenting a plurality of random binary signals to said input means to initialize the system prior to introducing message information thereto, matrix storage means for arranging a cipher key in an n×m matrix array, wherein m and n are greater than 1; a plurality of modulo-two adders interconnected with each other for adding selected elements from said matrix with binary signals obtained from said input means; feedback means connected to said plurality of modulo-two adders; non-affine transformation means connected to said feedback means for transforming the feedback signals present on the lines contained in said feedback means; shift control means connected to said non-affine transformation means for rearranging selected matrix elements within said n×m matrix array.
Claim 3
Dependent Claim
19 words
The system as defined in claim 1 wherein said plurality of modulo-two adders are arranged in a cascaded fashion.
Claim 4
Dependent Claim
19 words
The system as defined in claim 2 wherein said priming means is an external source of random binary signals.
Claim 5
Dependent Claim
50 words
The system as defined in claim 2 wherein said feedback means further comprises a plurality of lines connected to intermediate stages of said modulo-two adders and at least one line connected to an element within said matrix which element is also connected to one of said plurality of modulo-two adders.
Claim 6
Dependent Claim
16 words
The system as defined in claim 4 wherein said non-affine transformation means is a substitution device.
Claim 7
Dependent Claim
24 words
The system as defined in claim 5 wherein said substitution device comprises coding-decoding means for converting from one base number to another base number.
Claim 8
Dependent Claim
57 words
The system as defined in claim 6 wherein said matrix consists of a plurality of shift registers each capable of shifting information within the register for rearranging a column or row of the matrix; shift control output means for specifying the number of shifts that are to be executed by each of said plurality of shift registers.
Claim 9
Dependent Claim
188 words
A variant key cryptographic system comprising: input means for introducing a plurality of electrical signals in binary form as message information to be enciphered or deciphered; priming means for presenting a plurality of pseudo-random binary signals to the input means to initialize the system prior to introducing message information thereto, matrix storage means for arranging a cipher key in an n×m matrix array wherein m and n are greater than 1; a plurality of modulo-two adders interconnected with each other for adding selected elements from said matrix with binary signals obtained from said input means; feedback means connected to said plurality of modulo-two adders; first non-affine transformation means connected to said feedback means for transforming the feedback signals present on the lines contained in said feedback means; shift control means connected to said first non-affine transformation means for rearranging selected matrix elements within said n×m matrix array; second feedback means connected to selected elements of said matrix for providing a binary word to a second non-affine transformation means; said second non-affine transformation means generating a variant binary vector that is stored in selected elements within the key matrix.
Claim 10
Dependent Claim
188 words
A variant key cryptographic system comprising: input means for introducing a plurality of electrical signals in binary form as message information to be enciphered or deciphered; priming means for presenting a plurality of pseudo-random binary signals to the input means to initialize the system prior to introducing message information thereto, matrix storage means for arranging a cipher key in an n×m matrix array wherein m and n are greater than 1; a plurality of modulo-two adders interconnected with each other for adding selected elements from said matrix with binary signals obtained from said input means; feedback means connected to said plurality of modulo-two adders; first non-affine transformation means connected to said feedback means for transforming the feedback signals present on the lines contained in said feedback means; shift control means connected to said first non-affine transformation means for rearranging selected matrix elements within said n×m matrix array; second feedback means connected to selected elements of said matrix for providing a binary word to a second non-affine transformation means; said second non-affine transformation means generating a variant binary vector that is stored in selected elements within the key matrix.
Claim 11
Dependent Claim
17 words
The system as defined in claim 8 wherein said second non-affine transformation means is a substitution device.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-03-25 | 1983-09-24 | 1984-03-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-03-25 | 1987-09-24 | 1988-03-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-03-25 | 1991-09-24 | 1992-03-25 | $7700.00 | Window Closed / Lapsed |