[arin-ppml] Just a reminder of some quick mathematicsfor IPv4that shows the long term impossibility of it

Owen DeLong owen at delong.com
Mon May 16 18:55:49 EDT 2011

> Even though I enjoy healthy debate as much as anyone, I'm not sure what the point or relevance of this thread is?  Some participants here view universal end-to-end connectivity as an important goal and as such NAT being significantly harmful to the internet. Others of us believe that goal is not particularly desirable and possibly even harmful to the interests of a portion of the community....and thus NAT has significant utility that outweighs any potential harm.

The latter view presupposes an incorrect perception of both end to end and the capabilities of NAT.

If you have good firewalls, there is no harm in leaving the packet header unmangled.

The harm from NAT is huge and the utility of NAT is demonstrably small unless you are trying to conserve addresses.
The value of conserving addresses in IPv6 is demonstrably small, therefore, I find it very unlikely that the utility of NAT
could possibly outweigh the harm it is known to cause.

> Much like politics or religion, I don't believe either side will be effective in changing the others beliefs no matter how much verbiage is expended in the effort. That seems evident by the number of times this particular discussion has taken place on this list.  Is it possible to simply agree to disagree on the utility/harm of NAT and set aside that portion of the discussion?

Not really. NAT is a toxic-polluter issue and those in favor of it are rarely its victims. That would be sort of like
asking the residents of Bhopal to agree to disagree with Union Carbide about the utility/harm of irresponsible
chemical processing.

> Can we simply agree that at this particular point in time IPv4 address space continues to have some value/use to a significant portion of the internet community?

I don't think that is in dispute.

> If we can generally agree on that proposition, then it seems clear that ARIN still has some responsibility for setting policies in regards assignment of that space. The question of whether the rest of the worlds population of human's, llama's or house flies will be able to access the internet through IPv4 strikes me as entirely tangential to that point.

It is tangential to that point, but, it becomes quite meaningful to the discussion of what those policies should be.
Since this thread has covered both the fact that ARIN should continue to set policies (which some seem to take
as opinion rather than fact) as well as several aspects of what those policies should be, I don't think you can
discard content of the thread just because it is not relevant to one of the topics in the thread.

> FWIW, my particular hope is that IPv6 see's a steady increase in adoption so that people who do value publically addressable space can get it, IF they want it....and that NAT & IPv4 (and maybe even NAT66) continue to be available to those of us who prefer it as an option. The world is a diverse place, I don't see why the internet should not reflect that diversity in being able to cater to a varied and sometimes conflicting set of interests. Yes, that adds to the complexity of the system from an engineering standpoint....but so does manufacturing more then one size of shoe.

Because ISVs won't reflect that diversity and they will limit application features to the lowest common
denominator. I don't want to see the internet hobbled by NAT any longer than it already has been.


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