Stream ciphers for digital storage encryption
US11139959B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 1, 2019 |
| Grant date | Oct 5, 2021 |
| Priority date | — |
| Expiry date | Apr 3, 2040 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L9/50
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
An embodiment involves receiving a request to write data to a memory unit. The memory unit is divided into one or more logical blocks, each subdivided into groups of sub-blocks encrypted in accordance with a stream cipher. The memory unit maintains a transaction journal that marks each sub-block as dirty or clean. The memory unit stores keycount values for each of the logical blocks. The embodiment also involves: determining that the request seeks to write a portion of the data to a particular sub-block marked as dirty in the transaction journal, decrypting the particular logical block in accordance with the stream cipher, writing the portion of the data to the particular sub-block, incrementing the keycount value of the particular logical block, encrypting the particular logical block using the stream cipher, a key, and the keycount value, and writing the particular logical block to the memory unit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.