Re: Another NAT Traversal question

[Francis Dupont <Francis.Dupont@enst-bretagne.fr>]

 In your previous mail you wrote:

   Francis Dupont wrote:
   >    >From what I recall, the authors had given up on the transport mode and
   >    one of them had stated on this list that only 'tunnel mode' will be
   >    pushed for v2.
   >    
   > => I am afraid that there is no consensus to drop the transport mode,
   > so as the NAT traversal is in the charter, there is a problem to
   > really solve.
   
   Let's ask it this way: what is the real need for transport mode ESP
   to work over NAT?

=> we have no choice : we need transport mode and there are NATs (including
in the charter)...

   You can do everything with tunnel mode ESP, including L2TP/IPsec.
   
=> there are two important differences between tunnel and transport modes:
overhead and selector checking. The first one can be removed with good
compression, including header compression, but the second cannot: tunnel
mode and transport mode over a tunnel will be ever different.
IMHO if we have to give up something, it should be the NAT traversal...

Regards

Francis.Dupont@enst-bretagne.fr