WRT to influencing inbound traffic using BGP I always thought AS_Path prepend was used when you have two different ISP providers (ie peering with different autonomous systems) and MED was used when you had multiple links to the a single ISP (ie multiple peering session with the same autonomous system).
I just read something that states "bgp always-compare-med allows comparison of MEDs from different AS's" but I'm not sure how that would work if MED is an optional, NON-transitive attribute (how do your MED settings get passed your peer's AS?) And since "bgp always-compare-med" is not enabled by default (or is it?) you would have to assume that it was enabled by the ISP or that you've spoken about this with the provider. I would not have come to the conclusion that bgp always-compare-med was enabled based on the information you provided. In short, I think I would also have gone with the AS_path prepend option. Maybe I'll come to another conclusion once I understand how "bgp always-compare-med" works. On Dec 10, 2010, at 9:41 AM, Ryan Jensen wrote: > Is there a rule of thumb when to use AS_Path vs MED? Thanks! _______________________________________________ For more information regarding industry leading CCIE Lab training, please visit www.ipexpert.com
