-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Bradley Urberg Carlson wrote:
I have a few customers' customers, who appear at a local IX. Due to the MLPA-like nature of the IX, I hear their prefixes both at the IX and via my own transit customers. I normally use localpref to prefer customer advertisements over peers' advertisements.
There is a customer's customer who is advertising more-specifics at the IX (and using a different source AS, to boot). I can think of a couple ways to prevent hearing these, but thought I should ask for suggestions first.
I have seen the opposite of this as well. ISP X announces an aggregate at the local IX, but has some more specifics announced to the transit providers for TE needs. To avoid sending/receiving traffic over transit links and prefer peering route, they were suggested to also announce their more specific to their peers. In your case, if your customer's customer is multihomed, they might be announcing more specific in line with their own routing policies. If you don't like it - then you'd setup a specific filter, resulting most probably in asymmetrical routing. thanks - gaurab -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.7 (Darwin) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFHFJMlSo7fU26F3X0RAqYLAJ9suyoqQ5Q9qU6lJKaaH0imAznsUACgxKxk CDM0aL0Ij32L5By3lnVjFuQ= =CgYZ -----END PGP SIGNATURE-----