In the referenced message, Craig A. Huegen said:
On Fri, Feb 09, 2001 at 09:18:40PM -0800, Sean Donelan wrote:
==>Return the 172.16.0.0/16 block to the registry (ARIN, APNIC, RIPE or if ==>no one else IANA) and apply for multiple appropriately sized CIDR blocks ==>under the current registry allocation guidelines.
While I fully agree with this approach to deal with the issues mentioned, it will only exhaust the new address space more quickly. Why should we give up on 128/2?
/cah
When the blocks are returned to the registries, the registries may use them for allocation at their current prefix boundaries (/19 generally) just as they are doing with 24,61,62,63,64,65,66. I'ld say the vast majority of those who filter do so based at minimum on the minimum registry allocation guidelines. cf BCP4 To add to Sean's solution, I believe it would not be outside the realm of possibility that a RiR would not require an entity to return first, ask second. Working with them on sizing an appropriate block, and setting up a generous renumbering schedule would probably be entirely possible. To add another potential solution, since both of the entities mentioned are, in effect, part of the same organization, set up (a/multiple) GRE tunnels for sending data between the two orgs. Then announce the larger aggregate from the better connected of the two.