Customized BGP route selection Using BGP/MPLS VPNs

Vanbever, Laurent [UCL] François, Pierre [UCL] Bonaventure, Olivier [UCL] Rexford, Jennifer [Princeton, USA]

A large ISP typically learns many routes to remote destinations, and these routes differ in terms of their performance, cost, stability, and security properties. An ISP's customers may also have different preferences for the paths that would carry their traffic. For example, financial institutions may prefer the most secure paths (e.g., paths that circumvent untrusted ASes, such as ASes known to censor traffic), while providers of interactive applications like online gaming and VoIP may prefer short paths with low latency. If such options were available, customers might be willing to pay a higher price to have the paths they want. Yet some other customers may be perfectly happy with whatever path the ISP provides for a relatively low price. Yet, today's BGP requires each router to select a single best route, making it difficult for an ISP to select different routes for different customers. In this talk, we describe how an ISP can offer customized route selection using existing router mechanisms. Such a service requires to disseminate multiple BGP routes within the AS, perform customized route selection at each AS border router, and direct data traffic on the chosen interdomain paths. As a proof of concept, we present a configuration supporting customized BGP route selection based on the BGP/MPLS VPN machinery. We evaluate the overhead of our solution, and discuss how new BGP/MPLS VPN router features and protocol enhancements could improve its scalability.