[ntp:questions] NIST vs. pool.ntp.org ?

Magnus Danielson magnus at rubidium.dyndns.org
Thu Mar 28 12:22:15 UTC 2013

On 03/27/2013 10:45 PM, David Woolley wrote:
> Robert Scott wrote:
>> I am confused about the proper usage of pool.ntp.org and NIST.
>> pool.ntp.org seems to be a collection of private sector time servers
>> offered for all to use, but with registration expected for regular
> The pool system has no provision for enforcing registration. It wouldn't
> make sense to hand out a random server address if most of them then
> refused to serve you because you hadn't registered.
>> users. And NIST has a government run set of time servers. Neither
>> group (NIST or pool.ntp.org) seems to include or referece the other.
> I would hope all the pool servers ultimately reference their national
> equivalent of NIST and therefore what becomes, after the fact, UTC.
> I think you will find that Navstar (GPS) and WWV times are traceable to

Yes and no.

GPS is traceable to USNO. USNO and NIST have traceability between each 
other within the BIPM framework.

> MSF times are traceable to NPL.

NPL is traceable to both USNO and NIST within the BIPM framework.

>> Are they in competition? Who normally uses the NIST servers and who
>> uses pool.ntp.org?
> The open NIST servers are heavily overloaded, so probably don't serve
> the highest quality time, but they are likely to be around for a long time.

I would setup a local server under your control. It will help both from 
debugging and noise perspective.


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