[ppml] geo addressing

[Michael.Dillon at btradianz.com]

> if the city in question becomes an LIR or ISP, such that cutouts will 
not
> happen when address-users move out of the city, then this could make 
sense.
> 
> there is no sensible way to do it from the RIR level, however.

Cutouts can be largely prevented by filtering BGP announcements
of prefixes outside the city where they belong. This is analogous
to the existing prefix filtering. I agree that there is no sensible
way to deal with prefix filtering from the RIR level, and yet,
most ISPs do filter anyway.

Of course the RIRs could recommend filtering and publish an
up-to-date feed of all city-level reservations to facilitate
filtering. There are any number of things that can be done
to support and encourage using geotopological addresses in 
the way they are intended.

Given that the classic IPv6 addresses will still exist I don't
really see that there will be much problem because anyone who
doesn't fit into the geotopological model will simply not use
it in the first place.

The one mechanism that is available to the RIRs for mandating 
activity is the member agreement. It is conceivable that RIRs
could structure an agreement to mandate any number of activities 
and then only give out geotop addresses to city governments 
who sign an agreement. Those city governments, acting as LIRs
would then pass on the requirements in their member contracts.
Unfortunately, I don't see that as a feasible structure to work
worldwide. In some cultures it would fly. In others it simply 
would not work and could even run into legal challenges.

The things that work in the Internet tend to evolve from the
bottom up and tend to be imperfect in many details. 

--Michael Dillon