[ntp:questions] Bad NTP servers jeopardizing the pool.ntp.org initiative

Danny Mayer mayer at ntp.isc.org
Mon Apr 2 12:17:14 UTC 2007

David Woolley wrote:
> In article <878xdbquaj.fsf at arbol.wsrcc.com>,
> "Wolfgang S. Rupprech" <wolfgang.rupprecht+gnus200704 at gmail.com> wrote:
>> (ref http://www.pool.ntp.org/join.html) That comes out to ~5GByte per
>> month.  I'm not sure my ISP will be that happy with me if I committed
>> to that high an added load.  I would have much fewer worries if the
> For comparison, home users of ADSL on the main UK wholesale supplier
> are contended at a level that means that a monthly fair share of bandwidth
> is about 12GB, so 5GB is a significant amount of bandwidth.

All of this points to the fact that the NTP infrastructure needs work.
DNS is a well distributed infrastructure while NTP is not. We are
depending on just a few (relatively) NTP servers to provide time. Maybe
the real solution is to provide NTP service similar to DNS service.

>> The fastest way to break people of the habit of wiring in IP addresses
>> would be to only allow dynamic hosts into pools.  Unless they use the
>> hostname as they are instructed to, they won't get any time service
>> after a while.
> I think home users should be discouraged from being in the pools, because,
> as well as easily using up a large part of their share of the access network
> bandwidth, they are going to be particularly prone to variable delays due
> to contention in the access network.
> ADSL in the UK (and I think more generally) is actually carried by an
> ATM packet switched network to the local exchange.  ADSL peak rates 
> far exceed an equal share of the bandwidth of the ATM network provided.

Which is yet another reason not to put something like this in the pool.


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