On Wed, 5 Oct 2005, Matthew Crocker wrote:
This comes down to a little more than just "depeering" -- at least in the
BGP sense. There's active route filtering going on as well if connectivity
is dead; after all, I can bet the house that at least one of Cogent's
network edge peers has connectivity to Level3, and vice versa.
People who are single-homed to either Cogent or Level(3) are the ones who
are most likely to feel the pain of broken connectivity.