Method for the production of an error correction parameter associated with the implementation of modular operations according to the Montgomery method
US5751620A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 7, 1995 |
| Grant date | May 12, 1998 |
| Priority date | — |
| Expiry date | Nov 7, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F7/728
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method for producing a binary error correction parameter H=2.sup.2*m*k mod N with N being a binary data element, called a modulo, encoded on m words of k bits each. This method includes the following steps: PA1 1. loading of the modulo N into a first n-bit register with n=m*k and initialization of a second n-bit register at B(0)=0 PA1 2. production and storage of a data element B(1)=2*(B(0)-N) by bit-by-bit subtraction of B(0) and N, and left shift by one unit of the result, denoted R(0), of the bit-by-bit subtraction, and comparison of B(1) and N, PA1 3. production of a data element H.sub.int =2.sup.n+v mod N with v=(m*k)/2p, with p as an integer by the implementation of the following processing operation: PA2 for i as an integer from 1 to v, PA2 if B(i)<N then B(i+1)=2*B(i)-0), PA2 else B(i+1)=2*(B(i)-N), PA2 and bit-by-bit comparison of B(i+1) and N, PA1 4. production of the parameter H by the performance of p P.sub.field operations H.sub.int (j)=P(H.sub.int (j-1), H.sub.int (j-1))N, with j as an index ranging from 1 to p and H.sub.int (0)=B(v+1) or B(v+1)-N.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.