Re: draft-palet-v6ops-proto41-nat-00.txt

[alain.ritoux@6wind.com]

Hi,

 > Hi all,
 >
 > We just submitted a draft on usage of Protocol 41 over NAT boxes.
 >

I have some question about this draft.
You propose :
         v4           v4
     X ---- NAT-box ----- Tunnel Serveur -- v6 world
     *                       *
     *************************
         6in4 tunnel

1) OK, but if the NAT-box dosen't support proto 41, it will
need a firmware update. As to proceed with such an update
wouldn't it be more safe, to have th NAT-box be IPv6
compliant, hence allowing
       dual           v4
     X ---- NAT-box ----- Tunnel Serveur -- v6 world
                *            *
                **************
                 6in4 tunnel
hence removing the need for proto 41 support !

2) in case of NAT-box wih proto 41 support, how does it
work, when
    - several Host/routers want to have 6in4 tunnel towards the
      same tunnel serveur
    - the NAT-box a only ONE public address
because proto 41 doesn't provide ports as in UDP/TCP or ID as
in the ping, for additional multiplexing level.

3) do you have an estimation (like the one Christian Huitema gave
in his NAT classification) about how may NAT support proto 41 and
how many don't ?

4) anyway, if there is a NAT we don't known about in the way
and that does not support proto 41, all we can see is that
   eh! this tunnel doesn't work !!
don't you feel it to be risky for a tunnel broker to provide
solution that don't work in some case, he can't even predict ?


Regards.
Alain.
--
Alain RITOUX
Tel +33-1-39-30-92-32
Fax +33-1-39-30-92-11
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