RADclock delivers atomic clock accuracy through software

Stephen Withers
Wednesday, 07 July 2010 16:05

Business IT - Open Source

Researchers at an Australian university have created a collaborative system that allows participating computers to tell the time as accurately as an atomic clock.

Most computers synchronise their clocks with a time server that ultimately relies on an atomic clock. But network delays mean that synchronisation is not completely accurate, and the faster communications links become (eg, as the NBN is rolled out around Australia), the more important it is that devices' clocks are accurately synchronised.

"This army of computers can collaborate to create new services and applications but only if they know who is doing what and, particularly, when. With a super-fast network, tasks occur more frequently, and that requires computers to track the passing of time much more accurately," said University of Melbourne researcher Julien Ridoux.

Ridoux and his colleague Darryl Veitch have created a software clock called RADclock that provides an accuracy of one millionth of a second by comparing the 'ticks' of the quartz crystals that provide timing information to the participating computers.

"It's time-keeping using a brains trust, if you like - the computers talk to each other and adjust their clocks as a result," said Ridoux. 'We have designed the Robust Absolute and Difference clock (RADclock), a novel timing system, that is accurate, reliable and inexpensive. Under good conditions this achieves microsecond accuracy, which is as good as an atomic clock-enhanced computer. And it costs nothing to install."

RADclock is being tested across Australia with the cooperation of the National Measurement Institute (NMI), the Institute for a Broadband-Enabled Society, and the Australian Academic and Research Network (AARNet). An experimental network of RADclock reference clocks is being established in Australia with the cooperation of the NMI and AARNet.

The software is available for FreeBSD and Linux under the GNU GPL licence.