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Re: [DNSOP] DNSOP: question about hardening "something like mDNS" against attacks

Ted Lemon <mellon@fugue.com> Mon, 26 October 2020 17:05 UTC

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From: Ted Lemon <mellon@fugue.com>
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Date: Mon, 26 Oct 2020 13:05:42 -0400
In-Reply-To: <20201026165915.GA40654@faui48f.informatik.uni-erlangen.de>
Cc: dnsop@ietf.org, kaduk@mit.edu
To: Toerless Eckert <tte@cs.fau.de>
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Subject: Re: [DNSOP] DNSOP: question about hardening "something like mDNS" against attacks
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On Oct 26, 2020, at 12:59 PM, Toerless Eckert <tte@cs.fau.de> wrote:
> The networks where i am worried are not home networks,
> but something like an office park network, where supposedly each
> tenant (company) should have gotten their disjoint L2 domains, ... and then
> they didn't. And one of the tenants has a "funny" network engineer/hacker.

That’s pretty clearly the thing to fix.
 
> So, eliminate for your assessment the option of better
> protocols. Now, why would this heuristic then still be
> "very bad" ? To me it just eliminates the benefits of
> dynamic port signaling when there is an attack. And has no
> impact under no attack.

If you’re going to do that, you might as well just turn off mDNS entirely.

I don’t know whether or not this would also be true of GRASP, however.

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