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Free Clock Democratizes Atomic Accuracy
schliz writes "A new, trial network of software-based clocks could give data centers and networks the accuracy of an atomic clock for free. The so-called RADclock analyses information from multiple computers across the internet by collecting the time from each machine's internal quartz clock, the time it takes for this information to be transmitted across the network, and comparing all the information collected to determine a time that is most likely to be accurate, so machines are calibrated across the network with up to microsecond accuracy — as good as that provided by a $50,000 atomic clock, researchers say."
Might want to doublecheck your facts. GPS knows about the time difference, which isn't 12 seconds either btw, it is 19. The complete time message, which includes the correct amount, is broadcast every 12.5 minutes, so its possible that when you cold boot a gps, it will be off some amount of time before that is received. (12 seconds is common for lots of GPS engines, they have built in correct for the first 7 seconds of correction, but need the updated time message after connection to get the rest of the update)
The next generation protocol has already been invented too, the Precision Time Protocol (PTP) recorded as IEEE 1588, with open source implementations already available.
PTP isn't a replacement to NTP: it's trying to solve a different problem. It's not useful on a general company LAN, but rather on a network that controls robotics or measurement devices.
Some limitations of PTP:
* only one "grandmaster" clock, i.e., no redundancy
* no WAN connectivity; it's UDP multicast-only, and so not very routable
* no security/signing of timestamps; NTP has security extensions if you need to be able to trust the time
* patented by HP/Agilent; NTP is both open and free
http://www.meinberg.de/download/docs/ieee1588/meinberg_ieee1588_conference2005_whitepaper.pdf
PTP was designed for small subnets of systems where measurement instruments and robotic systems are running on. This isn't a general PC/server solution.