On Mon, 29 Nov 1999 22:45:17 PST, Ian King said:
> any "lack" because of it.  I don't play UDP-based games or employ any of the
> other relatively new protocols that are so sensitive to end-to-end-ness
> (should they be? was that a valid assumption?), so a NAT is a great solution

Well.. Urm... TCP and UDP both assume that one endpoint is talking
directly in real time to another endpoint.  The NAT problems only
start when the protocol carries IP address/port information (such
as the FTP 'PORT' command), and the NAT isn't aware of that protocol's
translation requirements (If you see *this* at offset 80 of *that*
packet, smash it to read *foobar* instead).

I'll grant FTP an exemption, it came well before NAT units became
prevalent (Was there an FTP-over-NCP before The Great IP Deployment?).
However, I do agree that anybody designing a protocol in the last 3-4
years *should* have designed it to be firewall and NAT friendly.
(Yes, I know that can be difficult in practice.  I guess that's today's
"Welcome to Reality").

                                Valdis Kletnieks
                                Operating Systems Analyst
                                Virginia Tech

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