Re: Policies: Routing a subset of another ISP's address block

[Randy Bush <randy () psg com>]

> You're going to have to exempt multihomed downstream customers from your
> anti spoofing filters anyway, whether they use your space, someone else's
> or their own.

indeed this seems to be the case.  which breaks the schemes for ingress
filtering based on forwarding table entries <sigh>.

> To put it another way, if you have clueful downstreams, you should
> delegate anti spoofing to them, they will do it closer to the edge where
> there is no asymetrical routing.

one of the rare bits of positive feedback here.  multi-homed customers do
tend to be a bit more clued.  so, in this too rare instance, the pain is
near some clue to fix it.

randy