Private use of non-RFC1918 IP space

Skeeve Stevens skeeve at
Tue Feb 3 22:28:29 UTC 2009

And for those kinds of applications, yell at your vendors to come up with a solution.


They say that there is about 2 years of ipv4 left.  Then we’re screwed.  If people sit with their thumbs up their asses now, and are not out planning budgets and migration strategies, they will be caught when they want to do network expansions.


Note… the running out of IPv4 will NOT effect your current operations in any way.  Your providers transit will (or already has) become dual stack, and you will continue to be able to talk to the internet as a whole unless native v6 only content starts to appear, which it will and then problems will appear.


This situation will be able to go on for years without your changing anything….. unless you want these applications to keep communicating with the ever growing internet on ipv6… and if you do, plan for it… decide if you’re going to do it now, in a year, or in 10 years and how you want to look to your shareholders or stakeholders… because eventually, they will ask… they may not want to pay for it just now… but there is a lot of things you can do before you have to start paying real money for things.


-          Getting your assignment/allocation

-          Developing your documentation/plan of how it will be assigned internally

-          Start to identify what parts of your infrastructure will not cope (everyone will need to use NAT-PT internally for some 10 years or more)

-          Start talking to your hardware and software vendors about v6 and understanding their product roadmaps, timelines and so on.


With all this, when it becomes inevitable you won’t have to suddenly do a ton of work…. Or you could buy ‘Migrating my corporate network to IPv6 for Dummies’





From: Dave Temkin [mailto:davet1 at] 
Sent: Wednesday, 4 February 2009 9:06 AM
To: skeeve at
Cc: 'Zaid Ali'; 'Roger Marquis'; nanog at
Subject: Re: Private use of non-RFC1918 IP space


The problem with that solution mainly being that the application itself still needs some sort of intelligence as well as the border device potentially doing L7 operations (header insertion/etc.) - unless you're OK with generally losing all information about the source of incoming traffic at the backend (except for looking at NAT tables...)


Skeeve Stevens wrote: 

With new dual-stack border devices people will be able to move bit by bit, and there is no real reason to have to run around and change everything that you have internally.  These will change and update over time.  These internal applications aren't running on public IP addresses anyway.
-----Original Message-----
From: Zaid Ali [mailto:zaid at] 
Sent: Wednesday, 4 February 2009 5:19 AM
To: Roger Marquis
Cc: nanog at
Subject: Re: Private use of non-RFC1918 IP space
I don't consider IPv6 a popularity contest. It's about the motivation and the willingness to. Technical issues can be resolved if you and people around you are motivated to do so. I think there are some hard facts that need to be addressed when it comes to IPv6. Facts like 
1. How do we migrate to a IPv6 stack on all servers and I am talking about the 
   thousands of servers that exist on peoples network that run SaaS, 
    Financial/Banking systems. 
2. How do we make old applications speak IPv6? There are some old back-end systems 
   that run core functions for many businesses out there that don't really have any
   upgrade path and I don't think people are thinking about this.   
>From a network perspective IPv6 adoption is just about doing it and executing with your fellow AS neighbors. The elephant in the room is the applications that ride on your network.
----- Original Message -----
From: "Roger Marquis"  <mailto:marquis at> <marquis at>
To: nanog at
Sent: Tuesday, February 3, 2009 9:39:33 AM GMT -08:00 US/Canada Pacific
Subject: Re: Private use of non-RFC1918 IP space
Stephen Sprunk wrote:

Patrick W. Gilmore wrote:

Except the RIRs won't give you another /48 when you have only used one
trillion IP addresses.

Are you sure?  According to ARIN staff, current implementation of policy
is that all requests are approved since there are no defined criteria
that would allow them to deny any.  So far, nobody's shown interest in
plugging that hole in the policy because it'd be a major step forward if
IPv6 were popular enough for anyone to bother wasting it...

Catch 22?  From my experience IPv6 is unlikely to become popular until it
fully supports NAT.
Much as network providers love the thought of owning all of your address
space, and ARIN of billing for it, and RFCs like 4864 of providing
rhetorical but technically flawed arguments against it, the lack of NAT
only pushes adoption of IPv6 further into the future.
Roger Marquis

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