Patent ID: 7926096
Filing Date: 2011-04-12
Classification: G06F,H04J,H04L

Abstract:
1. A method for operating a device, that does not have a local time clock that provides a measure of time on power-up of the device, to enforce a time-based transaction policy that requires a reliable time reference, comprising: establishing a communications channel to each of one or more network-attached time sources wherein at least one of the network attached time sources is a dedicated time server deployed to provide time service to a class of devices to which the device that does not have a local time clock that provides a measure of time on power-up of the device belongs; using each of the one or more communications channels to inquire from each of the one or more network-attached time-sources as to the current time; receiving the current time from each of the one or more network-attached time-sources; using the received current times from the one or more network attached time-sources to estimate a current time and to calculate a reliability index for the estimated current time; and using the estimated current time and the reliability index associated with the estimated current time to enforce a time-based transaction policy.