Consider the following network. ISP B provides national backbone serviceto regional ISP
Chapter 4, Problem P39(choose chapter or problem)
Consider the following network. ISP B provides national backbone serviceto regional ISP A. ISP C provides national backbone service to regionalISP D. Each ISP consists of one AS. B and C peer with each other in twoplaces using BGP. Consider traffic going from A to D. B would prefer tohand that traffic over to C on the West Coast (so that C would have toabsorb the cost of carrying the traffic cross-country), while C wouldprefer to get the traffic via its East Coast peering point with B (so that Bwould have carried the traffic across the country). What BGP mechanismmight C use, so that B would hand over A-to-D traffic at its East Coast peering point? To answer this question, you will need to dig into the BGPspecification.
Unfortunately, we don't have that question answered yet. But you can get it answered in just 5 hours by Logging in or Becoming a subscriber.
Becoming a subscriber
Or look for another answer