[ppml] [narten at us.ibm.com: PI addressing in IPv6 advances in ARIN]

[Michael.Dillon at btradianz.com]

> There is no way to get back the /48's assigned under PI
> space after a multihoming solution that makes sense arrives, 

Not so. The mechanism for retrieving these /48's is:

Step 1. ARIN introduces a new PI policy that issues
        some kind of different PI addresses that are
        aggregatable.
Step 2. ISPs concerned about routing table size start
        filtering the old non-aggregatable PI address
        blocks.
Step 3. ARIN begins a cleanup program to contact the
        holders of these old, mostly useless, /48's
        and asks them to return them to ARIN.

In fact, you could also make allocation of a 
future-style PI block conditional on return of
the old 2005-1 style PI blocks.

--Michael Dillon