3 ms·
It’s really the only way to do accurate time.
by whalesalad 3y ago
It’s really the only way to do accurate time.
- gambiting 3y agoWell no, it isn't - it's just that every other solution is several orders of magnitude more expensive.
- whalesalad 3y agoSo the pragmatic approach that everyone is utilizing (including AWS’ latest announcement for microsecond accuracy) relies on hardware GPS. Why am I being attacked here. This is how it’s done.
- pwagland 3y agoI'm not the one attacking you, but I think I can explain. Your original statement was quite absolutist "It’s really the only way to do accurate time." A statement which would have had more agreement would be "It’s really the only practical way to do accurate time."
- whalesalad 3y agoFair.
- skybrian 3y agoRadio clocks [1] often don’t use GPS. Many countries have a radio signal they can pick up. In the continental US, it comes from Fort Collins, Colorado. [2] [1] https://en.m.wikipedia.org/wiki/Radio_clock https://en.m.wikipedia.org/wiki/Radio_clock [2] https://en.m.wikipedia.org/wiki/WWVB https://en.m.wikipedia.org/wiki/WWVB
- callalex 3y agoThat suffers from the same vulnerabilities.
- sneak 3y agoI have trouble picking up WWVB indoors at home even without jamming.
- pwagland 3y agoTo be fair, this isn't really _that_ accurate, it's only good to about 10ms, GPS will get you to 0.001ms accuracy, at least with the right kit.
- romaindivuolo 3y agoTechnically you can broadcast a new time to your neighborhood and have most people late to work (the ones having that kind of clock alarm), it's far from secure and accurate.
- femto 3y agoPrecision Time Protocol [1] is an alternative. CERN has been using it as part of a project to achieve sub-nanosecond accuracy over a wired network [2]. [1] https://en.wikipedia.org/wiki/Precision_Time_Protocol https://en.wikipedia.org/wiki/Precision_Time_Protocol [2] https://en.wikipedia.org/wiki/White_Rabbit_Project https://en.wikipedia.org/wiki/White_Rabbit_Project