Access to the IPv4 net for IPv6-only systems, was: Re: WG Action: Conclusion of IP Version 6 (ipv6)

Tue Oct 2 20:07:19 UTC 2007

On 2-okt-2007, at 16:53, Mark Newton wrote:

> By focussing on the mechanics of inbound NAT traversal, you're
> ignoring the fact that applications work regardless.  Web, VoIP,
> P2P utilities, games, IM, Google Earth, you name it, it works.

O really? When was the last time you successfully transferred a file  
using IM? It only works half the time for me and I don't even use NAT  
on my main system myself. Some audio/video chat applications work  
well, others decidedly less so. The only reason most stuff works most  
of the time is because applications tell NAT devices to open up  
incoming ports using uPnP or NAT-PMP.

> IPv6 will happen.  Eventually.  And it'll have deficiencies which
> some believe are "severe", just like the IPv4 Internet.  Such as
> NAT.  Deal with it.

If you want NAT, please come up with a standards document that  
describes how it works and how applications can work around it. Just  
implementing it and letting the broken applications fall where they  
may is so 1990s.

> If you believe that v4 exhaustion is a pressing problem, then I'd
> humbly suggest that 2007 is a good time to shut the hell up about
> how bad NAT is and get on with fixing the most pressing problem.

"NAT is not a problem" and "running out of IPv4 address space is a  
problem" can't both be true at the same time. With enough NAT  
lubrication you can basically extend the IPv4 address space by 16  
bits so you don't need IPv6.

> If we're successful, there'll be plenty of time to go back and
> re-evaluate NAT afterwards when IPv6 exhaustion is a distant memory.

Right. Building something that can't meet reasonable requirements  
first and then getting rid of the holes worked so well for the email  
spam problem.