[arin-ppml] Fairness of banning IPv4 allocations tosomecategoryof organization

[michael.dillon at bt.com]

> So what would/should ARIN tell a startup ISP/IX that went out 
> today and (to save some cash) bought a bunch of ancient IPV4 
> routing gear that  was so old it cannot implement CIDR or 
> variable-length subnetting?
> And their customers have some  network application  that only 
> works correctly when a /24 is available to them.

First, you meant to say a class C address block, not /24. 
Older gear cannot handle /24s because that is a variable length
subnet masking block. A class C block from between 192/8 and
223/8 would provide a /24 sized block on older gear.

And ARIN should politely tell them to get stuffed because
policy doesn't currently allow for allocating blocks out
of specific address ranges. At the most, ARIN might give 
out one such allocation, but when they come back for more
they will fail the utilization test.

> They have a technical need for a /16,  because they need it 
> to allocate their 200 customers (each a class C, for an 
> average 20 or so hosts per network, probably dialup 
> customers,  but a custom app designed for them
> requires a /24) --   and due to said lack of VLSM, this passes for
> "efficient" utilization..  (that is,  as efficiently as it's 
> technically feasible,  given the strange designs they have 
> chosen of their own free will).

If this ISP had non-VLSM gear, then a /16 would not work and
a class B address block would also not work. They would require
200 or so class C blocks. You cannot subnet a class B address
block into smaller blocks. That's one benefit of VLSM where any
/16 can easily be subnetted into /24 blocks or any size you wish.

> At some point, there should be a way to draw a line between 
> *true* need and  avoidable need.

Yes.

> Or  "this particular utilization, is deemed an excessively wasteful
> technology, as a matter of policy";   e.g.  the technology itself  is
> considered to create a usage of addressing,  that we arbitrarily  deem
> to be unjustified   (regardless of the technical justifications).

Might be time for an IPv6 transition policy which restricts
address allocations for reasons like the one which you state.
It would just be a moratorium during the IPv6 transition
phase. After IPv6 usage is widespread, then IPv4 can be 
opened up again, and if some museum network wants to set
up a bunch of old non-VLSM routers using class B and class C
address blocks, let them have their addresses. Just not now.

--Michael Dillon