[ppml] 2005-1 status

Michael.Dillon at btradianz.com Michael.Dillon at btradianz.com
Tue Feb 7 05:06:11 EST 2006

> Nor are we supposed to be doing our best to waste IPv6 space by holding 
> an unstated "/48 per location" policy when a typical location only needs 
> or two /64s.

In fact you are wrong. According to RFC 3177
we are supposed to be giving a /48 unless we are absolutely
certain that the site will never ever need more than one subnet.
Therefore, if the site needs 2 subnets today, then they qualify
for a /48 with no questions asked. In fact, if they might add a
second subnet in the next 10 years, they also qualify for a
/48 today.

Here is a quote from RFC 3177:
4. Conservation of Address Space

   The question naturally arises whether giving a /48 to every
   subscriber represents a profligate waste of address space.  Objective
   analysis shows that this is not the case.  A /48 prefix under the 001
   Global Unicast Address prefix contains 45 variable bits.  That is,
   the number of available prefixes is 2 to the power 45 or about 35
   trillion (35,184,372,088,832).

> If an applicant came back with reasonable justification why their site 
> org) needed more than a /48 total, even to the level of a /48 per 
> I'm confident ARIN would go along with it.  There is nothing in the 
> that prohibits such if it's justified.

Justification means different things in the IPv4 world and the IPv6 world.
We need to be careful not to confuse the two.

--Michael Dillon

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