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Re: a radical proposal (Re: protocols that don't meet the need...)
From: Michael.Dillon () btradianz com
Date: Fri, 17 Feb 2006 09:48:49 +0000

Geo-topological addressing refers to RIRs reserving large
blocks of designated addresses for areas served my large
cities (over 100,000) population. When end users are located
in fringe areas roughly equidistant between two or more such
centers, the RIR simply asks the end user (or ISP) which is
the center to which they want to connect (communicate).
This addressing scheme operates in parallel with the existing
provider-oriented IPv6 addressing scheme but uses a different
block of IPv6 addresses out of the 7/8ths that are currently
reserved. No hardware or software changes are required for this
to work, merely some geographical/economical research to determine
the relative sizes of the address pool to be reserved for each
of the world's 5000 largest cities.

The routing system doesn't particularly care whether your "geo-topo"
addressing is imposed by governments, RIRs, or a beneveolent dictator;
in all cases, the result is Soviet-style central planning to force the
network topology to conform to your idea of what it "should" be rather
than following the economic realities of the those who would build the

Which part of "CHOICE" do you fail to understand? How does
adding another choice get equated to Soviet central planning?
In my opinion, central planning is what we have now. The IETF
has imposed the provider-centric addressing model on us without
asking whether we want that or not.

Since only 1/8th of the IPv6 address space used this
provider-centric model, there is plenty of room to offer
an optional, geo-topological addressing model. Geo-top
addressing is not about imposing a topology. It simply
recognizes that the network largely follows the physical
geography of cities linked by roads, and railways. It
allows everyone to receive the benefit of the "nuclear
survivability" inherent in IP by multihoming in their 
home city.

Interesting to see an argument for bottom-up design in a post which
otherwise calls for top-down planning of the network architecture.

That should have been a hint that you totally misunderstood
what I was proposing.

Methinks we are re-interpreting history here. The IETF didn't create an 
cartel" for IPv4. What CIDR did, and I think I can speak with some 
of authority on this subject, was to allow routing state to scale
in a non-exponential manner by encouraging address assignment to follow

This isn't about CIDR. This is about the idea that there is
a hierarchy of addressing with the ISP at the top, and the
end user as a serf of their ISP overlord. That model was
indeed imposed by the IETF, probably because at the time
they were mostly working with benevolent overlords, i.e.
universities. I want to see an alternative hierarchy so
that end users are not tied to one overlord/ISP.

In the interests of demonstrating why "geo-topo" addressing can't 
work without radical changes to the business and regulatory models of 
Internet, consider the simple example of a provider who has connections

Your example proves my point. There is no one right way
that works for all people. Let your provider continue to
use classic IPv6 addresses wherever it works better for 
them. But create geo-topological addresses so that people
who want local multihoming can do so without breaking your
brittle Global Routing Table.

Both of these requirements defy business sense,

It's easy to make statements like this in theory. But when
customers come, cash in hand, with requirements like the above,
most businesses find a way to negotiate terms. Not all
business actors are greedy and stupid. And innovation is
not likely to come from the dinosaurs who dominate the 
ISP space today. It will come from small upstarts and from
customers themselves demanding simple effective multihoming
without provider lock-in. In other words, small provider
independent geo-topological address blocks that are fully
routeable on the entire Internet, either as detailled
prefixes in their home city, or as a city/regional prefix

If you really want to combine transport identifier and routing locator 
a single "address", you give up a lot of flexibility. For routing to 
addressing must follow topology, so in such a network architecture the 
"topology independent address" (aka "provider independent address") is 
an oxymoron.

In geo-topological addressing, the address DOES FOLLOW topology.
Your problem is that you cannot see the forest for the trees.
A provider independent address does not necessarily mean topology

--Michael Dillon

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