Subject: mDNS discussion?

From: Freek Dijkstra <[email-masked]>
Date: Mon, 19 Jul 2004 18:04:56 +0200

Hi,

I got curious into the operating of ZeroConf, so I viewed the zeroconf.org
and multicastdns.org sites, read an article or two, noted the controversy
with LLMNR, and read draft-cheshire-dnsext-multicastdns-04.

This list seems pretty quiet (or the archive is broken...). That's too bad.
I'm just an innocent spectator, not really involved, who just want a "zero
configuration" network. I don't care if the solution is called ZeroConf,
mDNS, RendezVous, DNS-SD, LLMNR or whatever.

I understand that zeroconf involves 3 issues topics: automatic IP
allocation, name resolution and service discovery. (I don't understand the
last one, Automatic allocation of Multicast Addresses, yet).

The first, Link-local interface configuration seems more or less a done deal
with the 169.254/16 range and the draft-ietf-zeroconf-ipv4-linklocal-17.

The third, service discovery, seems focussed around DNS-SD, UPnP and SLP.
I'm probably ignore this (my time is unfortunately limited). My first
impression at least is that UPnP has unnecessary overhead, but I really
can't judge on DNS-SD and SLP.

The second, name resolution seems to focus on either LLMNR or mDNS. What is
the current status of mDNS? Should I conclude from the fact that
draft-cheshire-dnsext-multicastdns-04 is a individual submission (and can't
thus, according to IETF guidelines become a standards track RFC, but only
experimental or informational track), is not an IETF-endorsed activity, but
(probably just as important) a community-driven activity?

Two questions: is the above correct? In particular, are mDNS and LLMNR
compatible, and if not, does mDNS have functions LLMNR not have? Pointers
are welcome (I will read them both, but a short note or pointer is
appreciated).

Second, having just (partially) read draft-cheshire-dnsext-multicastdns-04,
is it useful to give feedback? I found an obvious type (FF0X::FB in section
25 should read FF02::FB), but I'm willing to give more feedback, if
appreciated. If so, were to sent it to? To this list, the authors
individually, or even [email-masked]?

Kind regards,
Freek Dijkstra

PS: for the curious and interested: I work for the University of Amsterdam,
and have been to IETF 52&53 when I was a student, but have no professional
interest anymore. Just personal curiousity.

---

From: "Philip Nye" <[email-masked]>
Date: Wed, 21 Jul 2004 09:56:04 +0100

Freek,

The Zeroconf group and this list has been dedicated almost entirely to getting the IPv4 Link Local address assignment specification done and there has been little discussion for a long time of the other topics you mention - in general each of the specs you mention probably has it's own list (where you will probably see many of the same people).

Other earlier objectives of the zero-config group were dropped either because of lack of progress or because they were being covered elsewhere.

For comparison of mDNS vs LLMNR or of SLP vs DNS-SD vs UPnP you are best looking not just at the specs and the appropriate lists, but at who is promoting or actually using them and in what circumstances and trying to assess the reasons (both technical and commercial) for that choice.

Philip