FW: Updated ARIN allocation information

Robert McKay robert at mckay.com
Thu Jan 30 17:13:20 UTC 2014

On Wed, 29 Jan 2014 14:16:43 -0800, Seth Mattinen wrote:
> On 1/29/14, 14:01, Leslie Nobile wrote:
>> Additionally, ARIN has placed in its reserves in 
>> accordance with the policy "Dedicated IPv4 block to facilitate IPv6 
>> Deployment" (NRPM 4.10).  There have been no allocations made from 
>> this block as of yet, however, once we do begin issuing from this 
>> block, the minimum allocation size for this /10 will be a /28 and the 
>> maximum allocation size will be a /24.  You may wish to adjust any 
>> filters you have in place accordingly.
> I know ARIN doesn't care about routability and all that, but good
> luck with those /28s.

"This block will be subject to a minimum size allocation of /28 and a 
maximum size allocation of /24. ARIN should use sparse allocation when 
possible within that /10 block."

Thanks for the initial sparse allocation for some time the /28 will be 
the only tennant of the covering /24 so they will be able to advertise 
the /24 aggregate as well as the /28. In time the reachability of the 
/28s should improve and if some other /28 is allocated inside an already 
populated /24 then as long as they can both see each other's /28s they 
can still both advertise the /24 aggregate - or perhaps agree for a 
common transit provider to do it. As acceptance of the /28s improves 
further and less traffic flows to the aggregates, perhaps large 
providers would agree to replace the customer /24 aggregates with a 
single /10 aggregate to help out the (hopefully few) stragglers who 
still filter /28s.


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