Patent ID: 8006094
Filing Date: 2011-08-23
Classification: G06F,H04L

Abstract:
1. A method comprising: maintaining, by a device that logs event times and document hashes, a first log of the event times and document hashes in a chained-hash format; associating, by the device, a first clock with the first log; entangling, by the device, the first log with a second log maintained by another device by adding a time-stamped synchronization entry to the first log, the time-stamped synchronization entry having a time indication associated with a second clock from the another device maintaining the second log and a hash of the second log, wherein the second clock from the another device is a trustworthy clock; tracing, by the device, the entangling of the first log back to the second clock that is trustworthy; determining, by the device, a level of accuracy of the first clock based on an assessment of accuracy of the second clock that is trustworthy; and determining reliability of timestamps in the first log based on observed accuracy of the second clock and a reputation of the another device that maintains the second log.