[ntp:questions] Quality vs. Quantity

Jan Ceuleers jan.ceuleers at computer.org
Mon Mar 24 17:46:38 UTC 2014


On 03/24/2014 04:58 PM, Paul wrote:
> On Mon, Mar 24, 2014 at 11:18 AM, Jan Ceuleers
> <jan.ceuleers at computer.org <mailto:jan.ceuleers at computer.org>> wrote:
> 
>     But I wonder what an active "connection" is in this context, since NTP
>     sits atop UDP.
> 
> These are IP based not TCP/IP.

So there's even less of a notion of "connection".

> And in fact the point of the paper is using PTP with the end result that
> the intra-farm "errors" should (it's four years later maybe they are) be
> in the nano-seconds.

Yes, that's true.

The OP wanted to know about NTP clusters, so I guess there are two
lessons here:

- either do what NIST did and ensure that your NTP cluster servers are
so closely synced with each other that they are indistinguishable by
clients;

- or ensure that your load balancer ensures an association between
clients and servers which persists for long enough (given the poll
interval, probably to be multiplied by a safe factor, e.g. 3).

Jan


More information about the questions mailing list