BCP38 - Internet Death Penalty

[adam.vitkovsky at swan.sk (Adam Vitkovsky)]

> If the best route you pick for the customer's advertisement goes to your
upstream instead of your customer, you won't advertise it to your peer. 
> And if your customer sets a BGP community defined to mean "don't advertise
to peers" then you won't advertise it to the peer. 
> Yet they may well transmit packets to you for which delivery to that peer
is directed by your routing table. 

Yes asymmetric routing would kill the update-based urpf unless there would
be an informational urpf NRLI we could use for these purposes

adam