On 03/09/2013 11:59 PM, Michael Orlitzky wrote:
> On 03/09/2013 08:42 PM, Walter Dnes wrote:
>> On Fri, Mar 08, 2013 at 07:41:13PM -0500, Michael Mol wrote
>>
>>> The trouble with NAT is that it destroys peer-to-peer protocols. The
>>> first was FTP in Active mode.
>>
>>   In its day, it was OK.  Nowadays, we use passive mode.  What's the
>> problem?
>>
> 
> It also doesn't work under NAT, it's just broken in the other direction.
> 
> 
>>> SIP has been heavily damaged as well.  Anyone who's used IRC is
>>> familiar with the problems NAT introduces to DCC.
>>
>>   Every ADSL router-modem I've run into recently has port-forwarding.
>>
>>> Anyone who's ever played video games online,...
>>
>>   A *CLIENT* that can't operate from behind NAT is totally brain-dead.
>>
> 
> But you must have one non-NATed "server" for anything to work. I assume
> that's what was meant by "it destroys peer-to-peer protocols." You have
> to draw an arbitrary distinction between machines that work together,
> "servers," and ones that don't, "clients."

Indeed.

> 
> The problem will become more and more apparent as ipv4 space dries up
> and everyone becomes a client. Although ISPs will be more than happy to
> sell you a useful connection, for a premium.

This has happened to a friend of mine...and he *can't* get a public IP
from his rural ISP.

> 
> Un-NATed addresses are like, type-O blood. Imagine how much better off
> we'd be if we could get everyone to switch their blood to type-O. Might
> be less painful than the ipv6 transition, too =)
> 
> 
>>> or who's tried hosting a Teamspeak or Ventrillo server, has had NAT
>>> get in their way as well.
>>
>>   Port-forwarding.
>>
> 
> Port forwarding can work, but only for one host when the ports are
> standardized. You can't forward e.g. port 443 to two hosts, so only one
> host behind the NAT can be accessible on 443.
> 
> If you're using your NAT as a firewall for one box, then who cares. But
> you can't put more than one machine behind it and have everything still
> work.

Since we've already run out of IPv4 addresses, port forwarding is
starting to fail even for that circumstance; if your ISP hands you an
RFC1918 address, you're screwed.