Patent ID: 8869288

Claim:
A method for performing a time-based operation in a memory device, the method comprising: performing the following in a memory device: authenticating an entity running on a host device in communication with the memory device; determining an identification of the host device; receiving a request to perform a time-based operation from the entity; determining whether the host device is trustworthy based on the identification of the host device; in response to determining that the host device is trustworthy, performing the following: using a time value from the host device to perform the time-based operation; and in response to determining that the host device is not trustworthy, performing the following: determining accuracy of previously-measured active time by comparing the previously-measured active time with a first time stamp obtained by the memory device from a trusted time server through the host device, which has been determined to be not trustworthy, wherein the previously-measured active time indicates time elapsed when the memory device was previously active, the memory device being previously active when it was connected to and received power from the host device; measuring current active time of the memory device relative to a second time stamp obtained by the memory device from the trusted time server through the host device, wherein the measuring is performed internally in the memory device when the memory device is active, the memory device being active when it is connected to and receives power from the host device; adjusting the measured current active time using the determined accuracy; generating a time estimate by applying the adjusted measured current active time to the second time stamp; and using the generated time estimate to perform the time-based operation.