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

Wed Nov 14 20:10:43 UTC 2012

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

> On Wed, Nov 14, 2012 at 12:08 PM, Ben S. Butler
> <Ben.Butler at 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