In einer eMail vom 18.07.2008 03:38:22 Westeuropäische Normalzeit schreibt
rw@firstpr.com.au:
I think
that geographical-based addressing arrangements, such as
those proposed in
the recent thread by Heiner Hummel and Iljitsch
ban Beijnum) are not worth
considering further because:
To the extent that routing
scalability depends on geographically
determined assignment of
address space, this is completely
incompatible with several
fundamental needs of providers and
end-user
networks:
1 - That organisations who have been
assigned address space
should be free to
use it at various sites, and these
organisations are frequently global.
100 % d'accord.What they should not be free to do is to combine the address
with a wrong geographical location (btw, I have different solutions in mind
which require either more or less accuracy wrt geographical
location.
(Otherwise, each branch of
an organisation - and
there could
be hundreds at the granularity required
by the geographic aggregation system - will want to
get a large slab of address space, to cope with
the
potential for future
expansion.)
2 - Since the scalability which
geographic aggregation
supposedly must
depend on routers forwarding packets
in
part or in whole according to their destination
(source too??) address, this is incompatible with
the need of organisations to have packets flow
along
paths which are determined by their
business relationships.
I support this need of organisations( combine the inter-domain-ly derived
and geographically organized topology with the entire intra-domain topology even
if the latter one spans the entire globe; enable inter-domain multipath as
extensively as demonstrated on my website, of course while taking care that
preferences can be made according to business relationships)
(It is assumed that
the Internet's routing and addressing
system should not require any organisations to have a
business relationship or handle each other's
packets
simply because they are in
some kind of geographic
proximity.)
Bill's challenge to Heiner
illustrates point 2 nicely:
http://psg.com/lists/rrg/2008/msg01815.html
http://psg.com/lists/rrg/2008/msg01829.html
3
- Organisations need to choose who they connect their networks
to according to various criteria which are at odds
with
geographical aggregation, including being
free to create
links to distant networks.
Scenarios include:
a - Redundant
paths to cope with (geographically) nearby
failures and points of congestion.
b - Similarly, paths (such as by a fibre link,
not
tunnelling through the
Net) which enable packets
to travel whilst meeting security and policy needs.
(For instance, for security - not
through any
given
country or company. Also, to meet local
Internet censorship, anti-terrorism etc.
laws,
it may be
necessary to make links which avoid
certain countries. Encryption is not a
proper
solution,
and security can be damaged just
by analysing traffic patterns, even if the
contents cannot be
deciphered.)
c - Efficient traffic
handling within global private
networks which nonetheless use public address space.
All of this can be supported much better than so far.
Having the scalability of the Internet's routing system depend
on
assigning addresses according to geographical location -
implicitly
with forwarding of packets being dependent upon those addresses
- is
completely incompatible with the business, policy, security
and
efficiency requirements of the great majority of providers
and
end-user networks.
Geographical aggregation is the sort of thing
which looks good on
paper, but will never be acceptable in the real
world.
This is a clear statement. My answering statement is this:
IETF was the first to do route computation but is meanwhile far
behind. We could do internet routing as perfectly as Google map can
compute a path from New York to L.A.
What it takes is a clean vision ( which I think I have), the
proper computation technology (which partly exists for 20 years) and a common
process to develop a new Topology Aggregating Routing Architecture (TARA).
Heiner