The Choice: IPv4 Exhaustion or Transition to IPv6

Lynda True (aka Etaoin Shrdlu) shrdlu at
Thu Jun 28 19:07:48 UTC 2007

Kevin Oberman wrote:

>>From: Stephen Wilcox <steve.wilcox at>
>> I wasnt specifically thinking of reclamation of space, I was noting a
>> couple of things:
>>- that less than 50% of the v4 space is currently routed. scarcity will presumably cause these non-routed blocks to be:
>> :- used and routes
>> :- reclaimed and reassigned
>> :- sold on
>Some of it, but a large part of the "missing" space belongs to the US
>Government, mostly the military. It is very much in use and is routed
>carefully such that it does not show up in the public Internet.

There's another set of missing space, here. It seems to be the elephant 
in the room. While I can't (or won't) speak to the routing issues 
mentioned in the thread, I wonder that no one has brought up all the 
legacy space that is held by a few large conglomerates. No, I'm not 
talking about AT&T, here. I refer to the early days, when class B 
networks were handed out like penny candy, and when organizations could 
get class C space equivalent to a class B. When Company A has, say, 5 or 
6 of those, and then acquires Company B, and then C and D, and all of 
them have that same allotment, it becomes a non-trivial amount of space. 
If there's really only 5 or 6 big companies, where there used to be 50 
or so, we are suddenly talking about a non-trivial amount of space.

Unfortunately, there's no good way to make them give it up. When you can 
see that they could easily make do with a single /8 (or less), it's 
rather sad that we don't have a mechanism in place that punishes for 
greed, and rewards for surrender of unused (or at least completely 
unnecessary) space. I only know about the industry I came from, of 
course, and I suspect that the lion's share of over-allocation is in it. 
I rather doubt that such things as banking, which came late to the 
table, have that characteristic. I know it's not a permanent answer, but 
it seems that (unlike the black space over on milnet et al) there's a 
temporary reprieve to exhaustion in there somewhere.

The more sand has escaped from the hourglass of our life,
the clearer we should see through it.
      Niccolo Machiavelli 

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