Secure management of access data for control devices
US11182495B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | May 15, 2019 |
| Grant date | Nov 23, 2021 |
| Priority date | — |
| Expiry date | May 15, 2039 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L67/12
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A control device of a machine or system data compares access data with a current access authorization. If there is a match, access to user data stored in the control device is permitted. The control device occasionally accepts encrypted verification data from an external computer via a network and stores them encrypted or unencrypted as current verification data, with the current access authorization being derived from the unencrypted current verification data. Verification data already stored in the control device as current verification data when the verification data are accepted are retained as old verification data, while older verification data are overwritten. The accepted access data are compared with an old access authorization derived from the old verification data. An operator can access the user data only if there is a match with the old access authorization.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.