[address-policy-wg] minimum allocation size in case of transform addresses

On 3/25/13 17:21 , Andrzej Dopierała wrote:
> Hi!
> I found today out, that there is planed possibility to convert PI
> assignments to PA allocation.
> But - i'ts planed only for /22 and bigger assignments, due to minimum
> allocation size, and doesn't apply for example /23 or /22 assignemnts.
>
> I think it's a bit pointless.
>
> AFAIK sense of minimum allocation is suppression of unnecessary
> fragmentation. But - in this case - this pool is already in use, and is
> already visible in bgp table. Allowing or disallowing conversion doesn't
> have any relation with growing address space.
>
> What's more - allowing conversion of any assignment can save some of
> address space. Most of PI assignemts (known to me) is partialy unused.
> After years from assignemnts part of the plans has been withdrawn (but
> another parts are citical  - dns servers etc - so whole assignemnt can't
> be returned). Allowing conversion would allow use it back, for example
> for customers...
>
> (sorry for my english - i hope that sense is understandable)

You probably still want to prevent the fragmentation of larger blocks 
into smaller blocks than the applicable minimum allocation size. 
However, if the block in question is already smaller then it should be 
transferable at its current size, you just can't fragment the block. 
Legacy /24s or PI blocks are easy examples of block that exist that you 
might want to all an LIR to receive.

Language like the following should work; "The minimum transfer size is 
the smaller of the original allocation size or the applicable minimum 
allocation size in current policy."

This is one reason to not completely eliminate all the existing IPv4 
policies with 2013-03.  They can still be useful, and may be useful in 
the future.  Otherwise, you have to revisit the consensus for issues 
like what the appropriate minimum allocations size should be in what 
situations.

-- 
================================================
David Farmer               Email: farmer at umn.edu
Office of Information Technology
University of Minnesota
2218 University Ave SE     Phone: 1-612-626-0815
Minneapolis, MN 55414-3029  Cell: 1-612-812-9952
================================================