[ntp:questions] zeroconf for ntpd?

Steve Kostecke kostecke at ntp.isc.org
Wed May 23 21:35:53 UTC 2007

On 2007-05-23, Wolfgang S. Rupprecht wrote:

> Steve Kostecke <kostecke at ntp.isc.org> writes:
> Looking at the usage graphs of the pools, there are only 2-6 million
> pools users.  That probably accounts for most of the ntp users in the
> world.  The current estimates are over 400 million internet-connected
> computers.  It is going to be challenging to pick up all these users
> using any unicast-based scheme.

One challenge is the fact that it is not uncommon for ISPs or other
network operators to block the NTP port.

>> 2. Muticast clients must use NTP authentication if they wish to control
>> which multicast servers they will accept. This requirement impacts
>> the autonomous configuration aspect of multicast (or manycast, for that
>> matter).
> This is the part that might be the easiest.  If a few well known
> stratum 1's (say NIST itself) were to emit signed multicast packets
> the clients could just pick the servers they trusted.

Assuming that multicast support is added to all of the routers on the
Internet and the network providers can be convinced to route multicast
packets and the network operators can be convinced to open the NTP port,
there's the issue of key management (especially in embedded devices).

Steve Kostecke <kostecke at ntp.isc.org>
NTP Public Services Project - http://ntp.isc.org/

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