Le 13/01/2016 18:36, Reza Motamedi a écrit : > Hi NANOG, > > I am researcher at the University of Oregon and my question is rather > primitive. My research background is in networked systems and Internet > measurement so I know how things work in theory. > > My question is about BGP and what can be inferred from the output of > different "show" commands, regarding the point of traffic exchange of two > networks with different ASNs. I tried going through the some samples on > Juniper and Cisco documentations but I did not get my answer. > > Consider the following scenario; Say the point of traffic exchange between > AS_a and AS_b is in San Francisco and we run "show bgp summary" and "show > ip bgp <prefix>"on a BGP router of AS_a in LA. Do we see the peering > between AS_a and AS_b in San Francisco using any of the two commands. If > yes is there a way to infer that in fact the traffic is not exchanged > locally in LA? I think there should be a flag to differentiate records > showing iBGP vs eBGP. > > On the same note, if we issue the commands on a router other than the > border router in San Fran, is there any difference in the output of show > commands? > > Now how are things different if we actually run the commands on that > gateway router in SF?
Hi Reza, A reasonably recent paper discussing AS relationships: http://arxiv.org/abs/1106.2417. Cheers, mh > > Best Regards > Reza Motamedi (R.M) > Graduate Research Fellow > Oregon Network Research Group > Computer and Information Science > University of Oregon
