NIST NTP servers

Eygene Ryabinkin rea+nanog at
Thu May 12 02:23:55 UTC 2016

Wed, May 11, 2016 at 05:20:28PM -0700, Scott Weeks wrote:
> --- mel at wrote:
>> From: Mel Beckman <mel at>
>> Accurate time to the millisecond is pretty much 
>> essential for any network troubleshooting. Say 
>> you want to diagnose a SIP problem. You collect 
>> transaction logs from both phones, the VoIP 
>> gateway, and the PBX. Now you try to merge them 
>> to derive the sequence of events. You NEED 
>> millisecond accuracy.
>> ----------------------------------------
> If all logs are sent to a unix server that does 
> syslogd the log entries would go into the file
> in order no matter what timestamp is on them.

Modulo latencies and jitter from different machines to the log server.
Millisecond precision can be harmed by this, easily.  Especially by
jitter and order of millisecond here isn't something non-existent
in a long-distant networks.
Eygene Ryabinkin, National Research Centre "Kurchatov Institute"

Always code as if the guy who ends up maintaining your code will be
a violent psychopath who knows where you live.

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