[ppml] "Recommended Practices" procedure

On 06/30/06 at 9:01am -0400, Robert E.Seastrom <ppml at rs.seastrom.com> wrote:

> Scott Leibrand <sleibrand at internap.com> writes:
>
> > To multihome with PA space, you must ensure that your transit providers,
> > and any of their transit providers (recursive), accept your /48 from each
> > other.
> >
> > Still pretty simple, no?
>
> There's an implicit assumption here that peers (as opposed to upstream
> transits) do not filter.  History has shown counting on this to be unwise.

No, I'm not making that assumption.  I'm saying that only your
transit-free transit providers need to exchange your route.  Everyone else
can send the traffic towards the provider's /32 aggregate, and once it
enters the provider's network the more-specific /48 will take over.
That's not ideal for traffic engineering or route optimization, but it's
adequate for reachability.

-Scott