[X4U] What is NAT and what does it mean to me?

[Tim Collier]

On Iyar 23, 5767, at 10:43 AM, Robert Ameeti wrote:

> At 10:30 AM +0100, 5/11/07, David Ledger wrote:
>
>> At 00:25 -0700 11/5/07, x4u-request at listserver.themacintoshguy.com  
>> wrote:
>>> From: Tim Collier <timjcollier at mac.com>
>>> Subject says it all.  I installed BellSouth DSL and connected the
>>> wired modem to my 802.11n Airport Extreme.
>
>> If it's just a modem it won't do NAT. (Although with the people who

>> you can have anything that could cause any error that could be  
>> described as 'Double NAT'. What item told you of the error?
>
> And the fact that both the DSL cable modem is doing NAT and his  
> AirPort is doing NAT, this causes the double NAT message.
>
>>> From: Robert Ameeti <robert at ameeti.net>
>>> Double NAT would be where the ISP's router was doing NAT and
>>> providing a 'network' of addresses and then one of the devices (your
>>> AirPort) hooked up to one of its ports was also doing NAT. It is not
>>> impossible to deal with but should be avoided when possible.
>>
>> It's fairly straightforwards to deal with.
>
> The problems that users today are dealing with is when they attempt  
> to set up a site to site VPN. Doing this with a double NAT setup in  
> not going to be easy with most equipment.

You can say that again.  I've been totally unsuccessful.  Good thing  
it's not super-critical.  I really didn't need the static IP anyway,  
it was a free option, so I took it.

Tim