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Re: What is BCP re De-Aggregation: strict filtering /48s out of /32 RIR minimums.


From: Michael Smith <mksmith () mac com>
Date: Wed, 14 Nov 2012 12:10:43 -0800


On Nov 14, 2012, at 10:06 AM, William Herrin <bill () herrin us> wrote:

On Wed, Nov 14, 2012 at 12:08 PM, Ben S. Butler
<Ben.Butler () c2internet net> wrote:
Yes, nice.  But... It does not address the case when this is
not the ISPs customers but the ISP (read content provider)
that operates globally but without a network interconnecting
their routers.

Hi Ben,

That case is covered by things like ARIN's multiple discrete networks
policy which permit an ISP /32 or end-user /48 for _each_ distinct
network. There are plenty of addresses in IPv6. You should be break up
a /32 for traffic engineering purposes, not for the sake of handling
multiple disconnected sites. And when exercising TE, you can offer a
covering route and expect the network as a whole to still function
regardless of other folks' suballocation filtering.

Regards,
Bill Herrin


I guess I'm confused.  I have a /32 that I have broken up into /47's for my discrete POP locations.  I don't have a 
network between them, by design.  And, I won't announce the /32 covering route because there is no single POP that can 
take requests for the entire /32 - think regionalized anycast.

So, how is it "worse" to announce the deaggregated /47's versus getting a /32 for every POP?  In either case, I'm going 
to put the same number of routes into the DFZ.

Mike


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