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NelsonMinaryesterday at 10:17 PM3 repliesview on HN

On the flipside, clock sync for civilians has never been easier. Thanks to NTP any device with an Internet connection can pretty easily get time accurate to 1 second, often as little as 10 ms. All major consumer computers are preconfigured to sync time to one of several reliable NTP pools.

This post is about more complicated synchronization for more demanding applications. And it's very good. I'm just marveling at how in my lifetime I from "no clock is ever set right" to assuming most anything was within a second of true time.


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Uehrekatoday at 1:31 AM

I was doing something at work that involved calculating round trip times from/to Android devices, and learned that although it should be possible for NTP to sync clocks with below-second precision, in practice many of the Android devices I was working with (mostly Pixels 2-7) were off from my server and each other by up to 5 seconds, which blew my mind.

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rarontoday at 1:03 AM

> clock sync for civilians has never been easier

I don't think civilian clock synchronization was an issue since a long time ago.

DCF77 and WWVB has been around for more than 50 years. You could use some cheap electronics and get well below millisecond accuracy. GPS has been fully operational for 30 years, but it needs more expensive device.

I suspect you could even get below 1 sec accuracy using a watch with a hacking movement and listening to radio broadcast of time beeps / pips.

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jasonwatkinspdxyesterday at 10:45 PM

At this point the only clock in my life that doesn't auto set is the one on my stove, and that's because I abhor internet connected kitchen appliances.

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