Subject: RE: draft-manning-multicast-dns-00.txt

From: Peter Ford <[email-masked]>
Date: Tue, 6 Apr 1999 09:48:05 -0700

Randy,

One person's first cut at goals and objectives:

1) allow for DNS name resolution in the absence of configured and
administered DNS servers (e.g. 2 hosts and a LAN scenario - perhaps we can
call this the home LAN scenario).

2) allow for DNS name resolution by a server in the absence of
preconfiguration of DNS server addresses on a DNS client ( note that this
behaviour is described in RFC 1123).  

Both of these goals can be nicely addressed with multicast DNS.   I
wholeheartedly agree that we need to be SAFE in the application of
multicast, but I do think this is addressed by administrative scoping.

Bill**2's proposal covers 2), I am adding 1) because it would be nice to
have a real replacement for NetBIOS name services (motivated by the desire
to introduce hierarhcy in the name space, and the desire to reduce the total
number of protocols an end system has to support).

When dealing with these sorts of issues, I keep a recommendation Postel made
to me several years ago in mind:  think about how this would work in the
IPv6 world, and then bring it back into IPv4.  I find this technique
valuable in keeping "current thinking/emotions" from clouding the
discussions.

cheers, peter

-----Original Message-----
From: Randy Bush [mailto:[email-masked]]
Sent: Tuesday, April 06, 1999 9:20 AM
To: Bill Woodcock
Cc: namedroppers
Subject: Re: draft-manning-multicast-dns-00.txt

> Rather than throwing up our hands and saying "multicast is bad, it uses
> packets, and they go all over the network!" it would be helpful to 
> remember that _nearly anything_ would be an improvement over the current
> situation, which is NBP and WINS

i suspect that the visceral issue here is that NBP and WINS are perceived
as being limited to a LAN and mcast is perceived as being net wide.  and i
do think i understand admin scoped mcast.  i am talking about why people's
instinctive first reactions to this proposal are not highly positive.  mcast
does not have a good rep this year.

> If we take too much time hand-waving on this one, it'll go right by, and
> implementations that you _won't want running on your network_ will be
> shipping in large volume.

you forgot the "my 10,000 customers demand it" part, jim:-).  our job is to
get the engineering as correct as we can, and presume that truth and justice
will prevail.

i suspect i could be convinced to like this proposal if it was more crisp
about goals and means, and if it made a clear and believable operational
prescription for limiting the scope of the chaos.  also, maybe separate the
stub server issue out, so it can be seen as a separate set of benefits to be
worth the major hack.

randy

---

From: Randy Bush <[email-masked]>
Date: Tue, 6 Apr 1999 23:51:04 -0700 (PDT)

Hey Peter,

> administered DNS servers (e.g. 2 hosts and a LAN scenario - perhaps
> we can call this the home LAN scenario).

in this scenario where is the multicast admin scope boundary?

randy

---

From: Masataka Ohta <[email-masked]>
Date: Wed, 7 Apr 99 21:49:41 JST

Peter;

> Both of these goals can be nicely addressed with multicast DNS.

Huh?

Are you saying that it allows for DNS name resolution by a server in
the absence of preconfiguration of DNS server multicast addresses
on a DNS client?
   I
> IPv6 world, and then bring it back into IPv4.

If IPv6 anycast addresses had ever worked...

							Masataka Ohta