Calculating unit and method for performing an arithmetic operation with encrypted operands
US7567668B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 16, 2004 |
| Grant date | Jul 28, 2009 |
| Priority date | — |
| Expiry date | Oct 18, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F2207/7238
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A calculating unit for performing an arithmetic operation with at least two operands, the at least two operands being encrypted, includes an arithmetic-logic unit with a first input for the first encrypted operand, a second input for the second encrypted operand, a third input for an encryption parameter and an output for an encrypted result of the operation, the arithmetic-logic unit being formed so as to operate on the first input, the second input and the third input by means of arithmetic sub-operations, while considering the type of encryption of the operands, such that at the output, an encrypted result is obtained which equals a value that would be obtained if the first operand was subjected to the arithmetic operation in a non-encrypted state and if the second operand would be subjected to the arithmetic operation in a non-encrypted state, and a result obtained was subsequently encrypted, no decryption of the operands being performed in the arithmetic-logic unit. In this manner, a processor system may be obtained in which no data whatsoever occurs in clear text, i.e. in a non-encrypted form, since no decryption upstream of an arithmetic-logic unit and no encryption downstre…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.