Re: What is NAT?

On Mon, 23 Jul 2007, in the Usenet newsgroup comp.os.linux.networking, in
article <m3sl7f49lo.fsf@xxxxxxxx>, Randy Yates wrote:

Can someone please (without asking me to Google) explain simply and
plainly what NAT is?

Well, let's see... it's going on 12:40 MST, or almost 8 hours since
you posted the "please google for me" request - and hitting that
search engine would have provided the answer in a few seconds. But as
you don't want to google, here's another suggestion:

[compton /usr/share/HOWTO]$ zgrep -wl NAT N*
NET3-4-HOWTO.gz
NetMeeting-HOWTO.gz
Networking-Overview-HOWTO.gz
[compton /usr/share/HOWTO]$

I know - that's to hard as well. Try this then:

http://www.netfilter.org/documentation/HOWTO/

[TXT] NAT-HOWTO.txt 24-Dec-2006 16:06 25K
[TXT] netfilter-double-nat-HOWTO.txt 24-Dec-2006 16:06 9.4K
[TXT] netfilter-extensions-HOWTO.txt 24-Dec-2006 16:06 79K
[TXT] netfilter-hacking-HOWTO.txt 24-Dec-2006 16:06 84K
[TXT] netfilter-mirror-HOWTO.txt 24-Dec-2006 16:06 8.1K
[TXT] networking-concepts-HOWTO.txt 24-Dec-2006 16:06 28K
[TXT] packet-filtering-HOWTO.txt 24-Dec-2006 16:06 52K

Is it, basically, the mechanism that my router uses to forward TCP or
UDP packets that come in to my router from the ISP to a specific machine
on my internal network (and vice-versa)?

Network Address Translation - works at the IP level. Your router replaces
your local address with it's own, BUT ONLY IN THE IP HEADERS. Your local
address could still be in application level data.

Old guy
.

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