Protected clock management based upon a non-trusted persistent time source
US8327448B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 22, 2005 |
| Grant date | Dec 4, 2012 |
| Priority date | — |
| Expiry date | Oct 12, 2028 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F21/725
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Methods and arrangements to persist a trusted time for a protected clock based upon a non-trusted but persistent time source are disclosed. Embodiments may comprise an embedded device, which may be hardware, software, firmware, and/or other logic, to maintain a trusted time in a protected clock. The embedded device may initialize the protected clock by obtaining a trusted time from a trusted time source such as a network server. The embedded device then maintains the trusted time in the event of a power loss to the protected clock by monitoring a time differential between the protected clock and a non-trusted system clock. Many embodiments also employ the protected clock without a battery backup to advantageously save manufacturing costs and space, while maintaining the trusted time in the event of a power loss by relying on a battery backup for the non-trusted system clock. Other embodiments are disclosed and claimed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.