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Re: BCP for multisite multihoming

On 22-mei-2007, at 19:42, Jason Schiller wrote:


The trouble is, for this to work without too much trouble, address
space needs to be given out with geography in mind. I don't think
IANA and the RIRs are going to do that without the IETF telling them
it's a good idea.



David said it already. The IETF won't waste it's time doing this so
long as it thinks that the proposal will go nowhere in
practice.
Oh, I'm sorry. I wasn't aware the current practice was entirely without problems and as such, out of the box thinking was neither required nor desired.
I concur. The problem with a geography-related approach to routing, is 
that all of the ISP networks also need to be reorganized to also be
related to the geography.


Says who?
UPS, Fedex, DHL and tons more of these guys all work with the same geographical addressing. They also all use their own ideas about what's the best routing in their own "networks". I got a package from DHL the other day. They sent it from New York to Brussels to The Hague. Most others send it through Amsterdam. They all get to decide all of this for themselves. But the important point is, that the driver in New York doesn't need a street map for The Hague for the package to arrive at my door.
The problem with all of this is that IETF participants almost always reject the notion of geography-related routing out of hand without really knowing what they're talking about. If I were to tell a second year computer science student that I have a sort algorithm that scales O(n) they'd tell me I'm crazy, too, because how can anything be better than qsort? There are of course reasons why qsort is used all the time and radix sort so rarely that it doesn't even get discussed in the text books, but if pure scalability to ridiculous numbers is what you need, then radix sort fits the bill and qsort doesn't.
In short all transit providers will need to restructure their networks to 
mirror the geographical regions.
All transit providers in a given geographical region would be required to 
do SFI-Peering,


What's SFI-Peering?
It is not clear what the approprate geographical region is-- should it be 
per continent? per country? per metro area of a give sized
polulation? per area code? per city? per LATA? per zip code designation? per sub-development? per street? per city block? per building? per floor?
Do you give each geographical region the same amount of IP space? What if 
a region consists entirely of desert or ocean? Should it be based on
population density?
Since you ask... Below is the text that explains the algorithm, but it's easier to simply look at http://arneill-py.sacramento.ca.us/ ipv6mh/geov6.txt 

   The geographical aggregation scheme splits the global routing domain
into a number of smaller regional ones, where flat routing happens in each region. Ideally, outside the region only aggregates are visible. 
   For simplicity and to allow efficient implementation, the framework
   presented here requires "areas" where flat routing takes place to
   have a fixed size: a /32 holding up to 65536 (2^16) fixed sized
   end-user /48 assignments. The maximum number of these /32 areas is
   also 65536. Areas are grouped in CIDR-like fashion if a geographic
region has a population that warrants allocating more than a single / 
   32. The highest level of aggregation is the subcontinent or "zone"
   level. There are 13 entities at this level, in order of population:

   1.   China

   2.   Continental Asia

   3.   India

   4.   Northern Africa

   5.   Asian Islands

   6.   Western Europe

   7.   North America

   8.   South America

   9.   Eastern Europe

   10.  Middle East

   11.  Southern Africa

   12.  Central America

   13.  Oceania

   The next level is the country level. Every country is assigned a
   range of /32 blocks, depending on population. Countries that are
   medium-sized or larger may be subdivided according to existing
   administrative boundaries, such as by state or province. The
   allocation size per state or province must match the population
   relative to the country and other states or provinces. The lowest
   level of aggregation is the metropolitan level. Cities of sufficient
   size are allocated one or more "metro areas". Assignments to
   end-users in, or very close to, a city are drawn from one of the
   metro area /32s allocated to the city. Addresses for end-users in
   small cities or rural areas are drawn from one of the /32 areas
   allocated to the country (if not subdivided), state or province (a
   country/state/province or "CSP" area).

8.1 Allocation policy

   The goals of the allocation policy are:

   1.  Be completely neutral, fair and unbiased, in order to minimize
       the potential for political complications

   2.  Good aggregation at all levels

   3.  Reasonable flexibility

   4.  Ease of implementation


8.2 Country Allocations

   Each independent country is allocated at least one /32 area. The
   allocation size depends on the country's population figure for the
year 2001. This is divided by the number D1, which equals 131072. The 
   result of the division is rounded up to the next power of two.

   This is the number of /32s constituting the country's allocation.

8.3 Zone Allocations

   The subdivision of the globe in 13 zones is relatively arbitrary.
   However, this division fits current and expected future Regional
   Internet Regions well, and limits the population per zone somewhat
   over a strict by-continent subdivision. Zone allocations are chosen
   such that they are large enough to hold the country allocations for
   all countries located within the geographic bounds of the zone. If
   for any of the zones that encompass more than a single country, the
   number of /32s not allocated to countries is less than 25%, the zone
   allocation size is doubled.

8.4 Subdivision of Large Countries

   When a country has an allocation of 32 or more /32s, this address
   space may be distributed over the country by allocating blocks of /
   32s to existing sub-entities such as provinces or states. The exact
   geographic bounds of these sub-entities must be clear to the general
   public and not subject to any controversy. The size of each
allocation is determined by dividing the population of the sub- entity 
   by the number D2, which is twice D1.

   At least 40% of the country allocation must remain unallocated. If
   necessary, a higher value than D2 may be used as a divisor in this
   country to reach this objective. The average number of /32 areas per
   state or province must be at least 4.

8.5 Metro Allocations

   All cities with a population of at least D2 within the city limits
   are allocated a block of /32s. The population for small cities or
   municipalities that do not qualify for an address block of their own
   is added to the closest city that qualifies, if there is one within
   40 kilometers. (Distance measured center to center.) The size of the
address block for a city and its surroundings is determined by taking 
   the total populace, dividing it by D2 and rounding down to the next
   power of two.