An operating system or other software resident on an electronic processing device employs aggregated timestamps. In this way timestamps can be generated and compared to one another without the need for a real-time clock with a power backup. Aggregated time includes the last known time that the device synchronized its clock with a reference time available over a network. Aggregated time also includes a relative time value which in part accumulates using a session clock whenever the device is powered-up. When network time becomes available the operating system or other software will use this information to fix up the already generated aggregated timestamps. A comparison of timestamps will most of the time be resolved for stamps generated on the same device and will generally be resolved by comparing time frames when the timestamps being compared are generated by different devices.