Jochen Hayek wrote:
>>>>>> "DB" == Daniel Beardsmore <public_at_telcontar.net> writes:
>
> >> No, dear friend!
> >> That's exactly what you should understand: The NAT server does this
> >> translation from private inside addresses and ports to that public
> >> address and also the reverse!!
> >>
> >> The NAT router.
> >> Try it yourself!
> >> I assume *your* NAT router has similar capabilities.
>
> DB> I don't know that they all do, you know.
> DB> I have a LinkSys EtherFast BEFSR41
> DB> and as far as I know, it doesn't alter any packets at all.
>
> Wrong.
> This is exactly, what makes the difference between a NAT router and a standard (non-NAT) router:
> The NAT router alters outgoing packets -- it replaces private IP adresses by its (the NAT router's) public IP address.
> a non-NAT router doesn't.
> A NAT-router keeps a memory of which private IP address communicated with whom outside,
> so that it will be able to alter incoming packets appropriately.
>
> If it wouldn't do all that,
> how do you think you would get any response on a private IP address going through a router?

Sorry, I was trying to say that they don't all rewrite private IPs
within packets themselves. i.e. the string "PORT 10.1.2.3" won't
necessarily be converted to a public IP by the router itself. Some NAT
routers take on this role and "fix" all your packets for you.
Received on 2007-02-12