Subject: [v4v6interim] "No DNS changes" in draft-wing-nat-pt-replacement-comparison-01

From: Andrew Sullivan <[email-masked]>
Date: Wed, 1 Oct 2008 16:29:15 -0400

I think I understand now what my problem was that I was trying to
state (incompetently, I think) at the mic.

In the overview of the items we were to discuss this afternoon, and in
draft-wing-nat-pt-replacement-comparison-01 table 2, we have this
claim:

   +--------------+-----------------+------------+---------------------+
   |   Proposal   |  ISP's Internal | DNS Impact |  Carrier Grade NAT  |
   |              |     Network     |            |                     |
   +--------------+-----------------+------------+---------------------+
   |    A+P-v4    |       IPv4      |  no change |     (no CGN, if     |
   |              |   destination   |            |   subscriber's NAT  |
   |              |   port routing  |            |   support A+P NAT)  |
   +--------------+-----------------+------------+---------------------+
   |    A+P-v6    |    IPv4/IPv6    |  no change |     (no CGN, if     |
   |              |      tunnel     |            |   subscriber's NAT  |
   |              |                 |            |   support A+P NAT)  |
   +--------------+-----------------+------------+---------------------+

I'm confused by the DNS Impact claim of "no change" here, if the
suggestion is that A+P is going to help v6-only clients talk to the
target hosts.  Is it instead the case that A+P is just not going to
help v6-only hosts?  That is, unless I'm misunderstanding badly (and
it wouldn't be the first time), a v6-only host can't talk to a v4-only
host using A+P without getting some way of talking to v4 networks,
period.  So maybe the DNS Impact in that table should be like NAT444?

A

-- 
Andrew Sullivan
[email-masked]
+1 503 667 4564 x104
http://www.commandprompt.com/
_______________________________________________
v4v6interim mailing list
[email-masked]
https://www.ietf.org/mailman/listinfo/v4v6interim

---

From: "Dan Wing" <[email-masked]>
Date: Thu, 2 Oct 2008 01:32:24 -0400

> -----Original Message-----
> From: [email-masked] 
> [mailto:[email-masked]] On Behalf Of Andrew Sullivan
> Sent: Wednesday, October 01, 2008 4:29 PM
> To: [email-masked]
> Subject: [v4v6interim] "No DNS changes" 
> indraft-wing-nat-pt-replacement-comparison-01
> 
>    |              |     Network     |            |            
>          |

A+P is all about IPv4 or a dual-stack host.  In either case, it would
access the IPv4 Internet using IPv4.  Also, in either case, the host does an A
record query and the host can process that A record query.  In that sense, I
agree it is like NAT444.

Table 2 probably tries to say too many things, as Table 2 is about IPv6 hosts
yet Table 2 includes NAT444, which doesn't support IPv6.  A+P (and Dual-Stack
Lite and SAM, for that matter) only support IPv6 subscriber hosts as a
side-effect; they do not intrinsically support IPv6.

-d

---

From: Andrew Sullivan <[email-masked]>
Date: Thu, 2 Oct 2008 02:54:21 -0400

> side-effect; they do not intrinsically support IPv6.

Yes, that was my impression.  I suggest leaving out cases where it's a
side effect from that table.  It's confusing otherwise (or at least,
it was to me).

A