Peering Games for critical internet flows Stefano Seccia,b, Jean-Louis Rougier a, Achille Pattavina b, Fioravante Patrone c, Guido Maier ba Télécom ParisTechb Politecnico di Milanoc Università di Genova2009 EuroNF Workshop on Traffic Management and Traffic Engineering for the Future Internet, December 7-8, 2009, Paris, France
Inter-domain IP routingcurrent practice across top-tier interconnections • Improvement of BGP routing in the Internet core • Routing decisions based on unilateral costs • Lack of routing coordination, especially on peering links • Routing on peering links is increasingly unstable • High risk of peering link congestion IGP weights reopt BGP route deflections • AIM: control the coupling between IGP and BGP routing ISP international ISP international Change of colour = change of top-50 carrier border (10 min sampling) ISP national ISP national ISP national ISP national ISP regional ISP regional ISP regional ISP regional ISP regional ISP regional
Coordinated inter-provider BGP routing a game-theoretic approach Coordinated Multi-Exit Discriminator (MED) game selfish + dummy + congestion games potential game Nash equilibrium minimum of the potential function IGP cost variations potential min. threshold enlargement of the Nash set Need for a coordination policy to select efficient multipath equilibria page 2
Coordinated inter-provider BGP routing NEED for a coordination policy: two examples Simple mono-pair 3-link ClubMED game The Nash equilibrium is unique and Pareto-efficient 13 13 13 14 15 10 page 3 4 The Pareto-superior Nash equilibrium is not Pareto-efficient any longer!
Coordinated inter-provider BGP routing DEALING with IGP path cost variations In practice, ASs may implement IGP-WO the IGP path cost can change after the route change Selfish game Gs adaptation. Each peer: Computes δ path cost variations w.r.t. each possible strategy profile Computes optimistic directional cost errors (ingress and egress) For example, egress error cost for AS I: Broadening of the Nash set and of the Pareto-frontier A potential threshold is arisen above the minimum More candidate Nash equilibria A coordination policy is still more necessary Tp
Coordinated inter-provider routing realistic emulations Peering Equilibrium MultiPath Routing policies NEMP, Pareto-frontier, Unselfish-jump, Pareto-jump Practical implementation via the MED attribute of BGP Lower routing costs, better route stability, inter-provider congestion avoidance page 5
Summary • Proposition of a routing game upon the usage of the MED attribute of BGP • Adapted for peering coordination rather than for transit settlements • Improvements: • peering link congestion avoidance, • reduction of bilateral routing cost, • control of the route deflections • Further work • Definition of a generic PEMP execution policy: when it is worth apply new sol? • Adaptation of the game modeling for other FI contexts (e.g., LISP)
Related publications • S. Secci, J.-L. Rougier, A. Pattavina, F. Patrone, G. Maier, "PEMP: Peering Equilibrium MultiPath routing", in Proc. of 2009 IEEE Global Communications Conference (GLOBECOM 2009), 30 Nov. - 4 Dec. 2009, Honolulu, USA. • S. Secci, J.-L. Rougier, A. Pattavina, F. Patrone, G. Maier, "ClubMED: Coordinated Multi-Exit Discriminator Strategies for Peering Carriers", in Proc. of 2009 5th Euro-NGI Conference on Next Generation Internet Networks (NGI 2009), Aveiro, Portugal, 1-3 July 2009. Best Paper Award. • S. Secci, J.-L. Rougier, A. Pattavina, F. Patrone, G. Maier, "Peering Equilibrium Multi-Path: a game theory framework for Internet peering settlements", submitted to IEEE/ACM Transactions on Networking.
Funding projects I-GATE: Internet – Game-theoretical Analysis of Traffic Engineering mechanismsFunded by Institut Télécom, ICF Networks of the Future Lab. Jan. 2009 - Dec. 2009.With Télécom ParisTech, PoliMi, UniGenova. INCAS: INter-Carrier Alliance StrategiesFunded by FP7 Euro-NF JRA.S.7. Sep. 2008 - Aug. 2009. With Télécom ParisTech, PoliMi, Alcatel-Lucent, WUT.