Subject: RE: (ngtrans) call for discussion on NAT traversial

From: George Tsirtsis <[email-masked]>
Date: Wed, 18 Jul 2001 12:00:58 -0400

-----Original Message-----
From: Keith Moore [mailto:[email-masked]]
Sent: Wednesday, July 18, 2001 4:43 PM
To: George Tsirtsis
Cc: 'Pekka Savola'; Alain Durand; [email-masked]
Subject: Re: (ngtrans) call for discussion on NAT traversial 

My assumption in writing 6overNAT was that the main problem with NATs
was not with ISPs that impose NATs, but with NATs that are deployed
in enterprise networks.    My understanding was that ISPs that impose
NATs on their customers are somewhat rare; this may have been incorrect
or the situation may have changed since then.

GT> What about DSL/Cable...these things often come with NAT as a default...I
had to search and ask for a no-NAT service to get one...most people I am
sure do not really care.

Naturally I'm happy if we develop a solution that works for both the
enterprise case and the case where the ISP imposes a NAT.  However 
I agree that any ISP that imposes a NAT on its customers (thereby
greatly impairing their ability to use some Internet applications) 
will not hesitate to block IPv6 traffic if they want to.  

GT> I do not think that ISPs impose NAT to customers on purpose but only as
a means to save addresses and as a poor man's security as we have discussed
a number of times before...Thus, I do not think that ISPs that deploy NATs
will want to block IPv6...it is likely that some will not care (as Pekka
said) and anyway, if they do want to stop IPv6 there is little we can do to
stop them.

GT> I would like to emphasize, however, that a very large number of small
size business networks get Internet services from small (cheap) ISPs that
either because of ignorance or economic reasons use NATs as a default...and
of course most small businesses do not even know what that means...Now if we
can have IPv6 in the hosts by default and make it usable with no net-admin
requirements...that would be really good...and of course that is not easy to
do...

George