From mboxrd@z Thu Jan  1 00:00:00 1970
To: 9fans@cse.psu.edu
Subject: Re: [9fans] IL and NAT 
In-Reply-To: Your message of "Fri, 17 Nov 2000 22:21:26 EST."
             <20001118032427.B11EB199E6@mail.cse.psu.edu> 
References: <20001118032427.B11EB199E6@mail.cse.psu.edu> 
From: Theo Honohan <theoh@chiark.greenend.org.uk>
Message-Id: <E13x8RD-0007iy-00@chiark.greenend.org.uk>
Date: Sat, 18 Nov 2000 13:53:50 +0000
Topicbox-Message-UUID: 2c8ff2d4-eac9-11e9-9e20-41e7f4b1d025

geoff@x.bell-labs.com wrote:
> scott wrote:
> >
> > Isn't it the case that some applications, like ftp, encode ip address 
> > and port information in application layer traffic, which NAT has to 
> > account for?  Linux seems to have code to handle that sort of stuff 
> > (linux/net/ipv4/ip_masq*). 
>
> I'm not sure; it's certainly possible that individual applications do
> such things.

I think Scott's right.  All viable NAT products do this, although it's not
strictly part of NAT.  A search for "NAT" on Cisco's site confirms
that they support the use of "PORT" in ftp, and a slew of features of
other protocols that would otherwise be broken by NAT.