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NIST was 5 μs off UTC after last week's power cut

jeffgeerling.com

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Re: NIST was 5 μs off UTC after last week's power cut

#151

Post by johncolanduoni »

dotancohen wrote: post #143
johncolanduoni wrote: post #142

Earlier quoted context omitted.

The victim firm would definitely notice, they’d tell the FCC, and their investigators will show up with a device that literally points them to wherever the jammer is. If you do this for stupid, silly reasons you will get fined[1], if you do it in commission of another crime you will probably get made an example of. It doesn’t matter how evil you are, it’s hilariously easy to get caught doing this. [1]: https://www.nj…

We are talking about the UK, not the US. And the jammer will most likely be tucked away in some closet with no hint as to how it got there.

Where were we talking about the UK? All anyone said in this message chain was HFT (and NIST).

Re: NIST was 5 μs off UTC after last week's power cut

#152

Post by johncolanduoni »

MadnessASAP wrote: post #146
johncolanduoni wrote: post #142

Earlier quoted context omitted.

The victim firm would definitely notice, they’d tell the FCC, and their investigators will show up with a device that literally points them to wherever the jammer is. If you do this for stupid, silly reasons you will get fined[1], if you do it in commission of another crime you will probably get made an example of. It doesn’t matter how evil you are, it’s hilariously easy to get caught doing this. [1]: https://www.nj…

> “Mr. Bojczak claimed that he installed and operated the jamming device in his company-supplied vehicle to block the GPS … system that his employer installed in the vehicle,” the FCC decision stated. I'm not surprised that somebody would try and do this. However it is just so stupid at every level.

Next to Newark Airport too. He’s lucky they didn’t throw the book at him - they could’ve hit him for reckless endangerment.

Re: NIST was 5 μs off UTC after last week's power cut

#154

Post by dotancohen »

johncolanduoni wrote: post #151
dotancohen wrote: post #143

Earlier quoted context omitted.

We are talking about the UK, not the US. And the jammer will most likely be tucked away in some closet with no hint as to how it got there.

Where were we talking about the UK? All anyone said in this message chain was HFT (and NIST).

Sorry, you are correct. As soon as the subject of HFT came up I was thinking about London and the things they do to reduce latency to the exchanges in North America. It's too late to edit or remove my previous message.

Re: NIST was 5 μs off UTC after last week's power cut

#156

Post by secondcoming »

creatonez wrote: post #102
secondcoming wrote: post #92

Earlier quoted context omitted.

I think Google uses chrony instead of NTP

Google doesn't use chrony specifically, just an algorithm that is somewhat chrony-like (but very different in other ways). It's called Google TrueTime.

Oh right. Their cloud-init script uninstalls NTP and installs chrony each time our VMs boot

Re: NIST was 5 μs off UTC after last week's power cut

#157

Post by broretore »

blibble wrote: post #73
dmurray wrote: post #67

Earlier quoted context omitted.

It's 1 us granularity , which means you should report your timestamps with six figures after the decimal point. The required accuracy (Tables 1 and 2 in that document) is 100 us or 1000 us depending on the system.

> The required accuracy (Tables 1 and 2 in that document) no, Tables 1 and 2 say divergence, not accuracy accuracy is a mix of both granularity and divergence regardless, your statement before: > The regulatory requirement you linked (and other typical requirements from regulators) allows a tolerance of one second, so it doesn't call for this kind of technology. is not true

any time i am certain of something i never capitalize and i do not end my sentences with periods or use any punctuation because i like people to believe i am an omniscient narrator who cannot be interrupted

Re: NIST was 5 μs off UTC after last week's power cut

#158

Post by nottorp »

mrguyorama wrote: post #150
voidUpdate wrote: post #132

Earlier quoted context omitted.

I'd have thought Jeff to be above clickbait, but here we are

If Jeff wants to maintain his job of making Youtube videos, youtube itself forces him to make clickbait thumbnails and titles. They have A/B testing infrastructure available to creators for exactly that purpose. If you say "Oh but he doesn't have to use that" you are wrong. If a creator's videos get low enough click through and "engagement", youtube just stops showing it to people. Jeff, like every creator on youtube…

I'm afraid you're preaching to someone who doesn't watch talking heads :)

My only interaction with Jeff's articles are through transcripts if they make it to the HN front page.

Re: NIST was 5 μs off UTC after last week's power cut

#159

Post by nottorp »

nottorp wrote: post #158
mrguyorama wrote: post #150

Earlier quoted context omitted.

If Jeff wants to maintain his job of making Youtube videos, youtube itself forces him to make clickbait thumbnails and titles. They have A/B testing infrastructure available to creators for exactly that purpose. If you say "Oh but he doesn't have to use that" you are wrong. If a creator's videos get low enough click through and "engagement", youtube just stops showing it to people. Jeff, like every creator on youtube…

I'm afraid you're preaching to someone who doesn't watch talking heads :) My only interaction with Jeff's articles are through transcripts if they make it to the HN front page.

Too late to edit so...

>I watched it too because I had no idea that weather was causing such a problem in Colorado and love hearing about NIST and the people who basically run the infrastructure of the internet that everyone takes for granted.

Are you aware that text based news about the NIST problems have been posted on HN in the past few days?

Re: NIST was 5 μs off UTC after last week's power cut

#160

Post by idiotsecant »

NetMageSCW wrote: post #83
idiotsecant wrote: post #27

Earlier quoted context omitted.

Lots of things do. Shoot, even plain old TDM needs timing precision on the order of picoseconds to nanoseconds.

But does that require accurate UTC?

Yes, in some implementations.
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