Method and apparatus for protecting numbers and strings using format-preserving encryption with automatic precision
US12368572B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 17, 2021 |
| Grant date | Jul 22, 2025 |
| Priority date | — |
| Expiry date | Aug 12, 2042 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L9/0894
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
Techniques for Precision-Preserving Format-Preserving Encryption (PPFPE) to protect numeric values and strings with leading/trailing and special characters, while preserving their precision, both as a protected value (e.g., ciphertext) and when decrypted are provided. In one aspect, a plaintext string is parsed to detect a first and last sentinel characters, wherein any character(s) preceding the first sentinel character comprises a leading character(s) and any character(s) following the last sentinel character comprises a trailing character(s). Any leading character(s) preceding the first sentinel character and/or any trailing character(s) following the last sentinel character are passed through. A ciphertext string is generated by encrypting the first and last sentinel character using one or more subsets of a set of encryption characters; and encrypting the portion of the plaintext string between the first and last sentinel character using the set of encryption characters.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.