Re: Customer AS

[randy () psg com (Randy Bush)]

Hi Hank,

> > > Not sure what you mean here concerning 'unroutable' prefixes, but the
> > > issue with obtaining an allocation for one of the upstream provider's
> > > CIDR block when multihomed *does* have its drawbacks, at least from
> > > the end-user perspective. If said prefix (let's say a /24) is announced
> > > in the 'allocating' provider's aggregate, and the more specific is
> > > announced via the 'other' provider, the more specific will always be
> > > preferred.
> >
> > This is brain damaged.  Given
> >
> >
> >            AS1 ----- Sprint
> >             |
> >             |
> >             |
> >             |
> >            AS2 ----- anything else not Sprint
> >
> >
> > You can not announce a bit of Sprint space AS1->AS2->MCI as a fallback
> > (note the 'extra' AS hop) because Sprint aggregates your announcement
> > and the longer prefix is announced to the world via <anything else>.
> >
> > Use Sprint space, bye bye fallback.
> >
> > To the best of my knowledge (which ain't that hot), all other providers
> > have discovered suppress-map.
>
> This is mainly due to the fact that Sprint does not listen to any
> announcements from its peers for anything within its "non-portable"
> blocks.

What?!?  I.e. if a Sprint customer C is multi-homed and their Sprint line
goes down, traffic to C from other Sprint customers will not be able to
reach C?

> BTW, Sprint also does not listen to any of its peers ASes through
> other peers so peering with Sprint and still paying someone for
> transit services do not help you get more redundancy with Sprint's
> network.

And this is considered good networking architecture?  Jeezus!

randy
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