Subject: Re: On Scaling of DNS-SD

From: Keith Moore <[email-masked]>
Date: Wed, 31 Jul 2002 10:00:01 -0400

> > some nodes in an applicaiton may be using addresses obtained from mDNS at
> > the same time others are using addresses obtained from DNS - if the two
> > views are inconsistent (and they will be) this can break the application.
> 
> the more serious worry would seem to be would data leak from the internal
> ersatz data into the real dns and start poisoning it globally.

that would certainly be a concern also.  in general any inconsistent view caused
by the introduction of mDNS - whether it be leakage of bogus mDNS records into 
DNS or leakage of bogus mDNS records into applicaitons that had some nodes
using DNS  - should be cause for concern.

People keep assuming that it's okay to have different views of DNS according
to location in the network topology. I don't share that assumption.  Applications
don't recognize network topology boundaries.

Keith

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From: Bernard Aboba <[email-masked]>
Date: Wed, 31 Jul 2002 06:37:40 -0700 (PDT)

> ersatz data into the real dns and start poisoning it globally.

One could imagine a scenario where a node attempts to do a DNS Dynamic
update for a linklocal address, for example. I suspect that few DNS
servers will automatically drop such an update today.

This is one of the reasons why the mDNS and DNS caches are separate and
also why DNS servers are prohibited from answering mDNS queries for RRs
for which they are not authoritative.