Protected mode for securing computing devices
US9690498B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 31, 2015 |
| Grant date | Jun 27, 2017 |
| Priority date | — |
| Expiry date | Aug 4, 2035 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F21/57
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Methods and systems are disclosed for testing and/or validating that an untrusted device is operating according to an expected state or configuration. The methods and systems may be designed such that the volatile memory of the untrusted device is brought to a known state for validation, for example upon ingress to or egress from a protected mode of operation. The device may execute a first operating system when operating outside of the protected mode. Upon determining to transition to protected mode, an operational image of a second operating system may be loaded into the device. The device may write a pattern to unused memory for validation. The device may receive a first challenge request from a trusted monitor (TM). In order to be successfully validated, the device may answer the challenge correctly within a given response window based on the current state of its volatile memory.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.