OPCA : Overlay Policy Control Architecture for BGP

1. Evaluation Problem • Analytical • Using real topologies, real BGP data • Calculate potential improvement • Implement and emulate • Code complete architecture • Use software BGP speakers (GNU Zebra) • Use Planetlab infrastructure • Measure convergence, traffic balancing, overhead, scalability • Multihoming • Increasing trend • For failover and traffic load balancing • But BGP failover takes ~15 minutes! • Can only manage outgoing traffic • Data shows • Multihoming trends • Trying to manage incoming traffic can have bad global consequences • Goal • Reduce route failover time • Improve incoming load balancing • Reduce time to switch traffic between paths • Not worsen route flapping • Not worsen table bloat • Coexist with IGP & BGP • Incrementally deployable Updates by Prefix Multihoming OPCA Architecture Design Challenges • Local optimization is not enough • Locus of control is remote • Current BGP tricks are unscalable, ineffective • Global optimization is unattainable • Computationally complex • Link state scalability problem • Full disclosure of policies is bad • Middle ground needed • Logically separate routing control plane • Find loci of control • Negotiate policy control • Adapt to non-responsiveness • Adapt to network change OPP Messages Relationship Inferences AS Hierarchy AS Z MI PD E-BGP PA Other AS domains/networks in the Internet PA Directory RMAP AS X PA E-BGP sessions EBGP E-BGP PA MI PD AS W AS Y E-BGP speaker OPCA : Overlay Policy Control Architecture for BGP Sharad Agarwal, Chen-Nee Chuah, Randy Katz