question about draft-durand-v6ops-natv4v6v4-00

[marcelo bagnulo braun <marcelo@it.uc3m.es>]

Hi Alain,

in you draft in section 4.2 you state that:

   The first drawback is that
   some applications may have a more difficult time going through two
   levels of NAT.

Can you point some examples for this case?

Then in section 4.3 you state that:

   The implications of this second level of translation is very similar
   to those in the model above of a double IPv4->IPv4->IPv4  
translation.

There were two concerns in the previous case, the applications that  
can fail more when there are two levels of nat than when ther is one  
level of nat and that a big provider rfc1918 addrsses may not be enough.
But the concern of running out of RFC 1918 addrsses for big providers  
does not exists when using IPv6 in the internal netwrok of the  
provider, so there is only the problem with the apps thatfail more  
when there is a single level of nat than when there is 2 levels of  
nat, right?

Do you think that current nat traversal techniques would not work  
properly if multiple levels of nats need to b traversed?

Regards, marcelo