Format-preserving cipher
US10009169B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jul 1, 2016 |
| Grant date | Jun 26, 2018 |
| Priority date | — |
| Expiry date | Dec 29, 2036 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2209/34
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A format-preserving cipher including encryption and decryption schemes supporting non-linear access to input data by allowing the selection of portions of data from a potentially larger dataset to be encrypted. The cipher first defines a forward mapping from the allowable ciphertext values to an integer set of the number of such allowable ciphertext values, and a corresponding reverse mapping. It also supports exclusion of a certain set of characters from the ciphering process. An encryption algorithm is provided that encrypts the input plaintext data while preserving its original format and length, and a corresponding decryption algorithm is provided. The cipher advantageously embodies the encryption and decryption of multi-byte values, composite datasets, credit card numbers and discontinuous datasets, thus fitting a variety of industrial needs.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.