[arin-ppml] Rationale for /22

[Jon Lewis]

On Thu, 30 Jul 2009 bmanning at vacation.karoshi.com wrote:

> On Thu, Jul 30, 2009 at 01:56:43PM -0400, Leo Bicknell wrote:
>> In a message written on Thu, Jul 30, 2009 at 12:19:19PM -0500, George, Wes E [NTK] wrote:
>>> To the question of "existing filters/inertia aside, is there a
>>> justification for *any* minimum allocation size?"
>>
>> While it is a bit of a reductio ad absurdum argument, consider what
>> (could) happen if the minimum were a /32.
>
>
> 	kind of like what happens when we give out everyone a /32
> 	of IPv6 space.  your arguments are identical for either
> 	an IPv4 or IPv6 /32.
>
> 	and yet we find it acceptable to hand out /32's in one space...

The difference being, v6 is so much bigger than v4 that the idea seems to 
be to give each network (whether that's an RIR allocating to an LIR, or an 
LIR assigning to a customer) more space than they could possibly use in 
the forseeable future with idea that v6 is so vast we're not going to run 
out, so give them their one big block now and be done with it.  After 
years of being conservative with v4 assignment, this is kind of a hard 
transition to make...and only time will tell if its a repeat of the 
mistakes made in the early days of v4 when big blocks were handed out and 
PI space was given to anyone who filled out the right template.

>> Everyone with a computer can justify a single address.  There's no
>> way global backbone routers can support a prefix per-user, even for
>> a modest amount of users.  Many of these users would be single
>> homed, taking the main advantage of a portable /32 as being a
>> "vanity" IP address.  Presumably the price for a single address

I don't think anyone is suggesting lowering the minimum allocation size 
for single homed networks.  If so, I missed that.

>> I think many folks miss the most important item though when considering
>> the effects of minimum allocation size, or other polices that are
>> likely to affect the size of the global table.  The single most
>> important thing is predictability.  ISP's are buying equipment now
>> based on growth assumptions.  They want that equipment to have a
>> reasonable lifespan (3, 5, 7 years?).  If our policies and actions

What good is your 7 year life router if you can't get any more IP 
addresses to route through it after 3 years?

----------------------------------------------------------------------
  Jon Lewis                   |  I route
  Senior Network Engineer     |  therefore you are
  Atlantic Net                |
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