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Re: on NAT-PT
>The following text is an extract from
>draft-huitema-ngtrans-unmaneval-01.txt, section 3.2.1: the problem with
>address translation:
(snip)
>In short, the problem is that inserting the DNS-ALG function in a
>gateway might be beneficial in the IPv4-only to IPv6-only scenario, but
>is detrimental in the scenarios that involve dual stack hosts. Since
>there is likely to be many more dual stack hosts than IPv6 only hosts,
>this means that NAT-PT as its stands is detrimental to IPv6 transition.
i don't think you have checked my initial posting.
header is attached as an evidence.
itojun
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Subject: on NAT-PT
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there are some concerns raised in the working group meeting
with respect to NAT-PT. it seems to me that the concerns does not
have enough technical ground (or there are some confusions in
understanding how NAT-PT works). i don't see the need for revising
NAT-PT at all. some clarifications on the document might be nice,
but no major re-work is needed, IMHO.
itojun
(snip)
draft-huitema-ngtrans-unmaneval-01.txt, page 4:
>This section makes an important assumption: it assumes that the NAT-
>PT acts as a bridge between two networks, one IPv6-only and the
>other IPv6-only. As a result, the DNS-ALG will translate a DNS
"and the other IPv4-only", i suppose.
>request for a AAAA record coming from the IPv6 host into a request
>for an A record, and vice versa. The problem is that address
>translation does not know if the traffic originates from an IPv4
>only/IPv6 only node or from a dual stack node. When a dual stack
>node A wants to communicate with an IPv4 only host B, the dual stack
>host A gets either the IPv4 address of B (preferred) or an IPv6
>address which is some kind of translation of the IPv4 address of B.
>This latter situation is not wanted, because it means unnecessary
>translation between IPv4 and IPv6. This is shown in the table below.
the answer is simple - don't use DNS-ALG if you are a dual stack node.
use DNS-ALG as your recursive resolver only when you are IPv6 only
node (hence you use NAT-PT translation part if the ultimate
destionation is IPv4-only).
- References:
- RE: on NAT-PT
- From: "Christian Huitema" <huitema@windows.microsoft.com>