UCB Tools for Smart Networks Jean Walrand BITS (Berkeley Information Technology & Systems) U.C. Berkeley
UCB Outline What are Smart Networks? Why Smart Networks? Tools for Smart Networks Project Example 1: DiffServ Example 2: Bandwidth Allocation Conclusions
UCB What are Smart Networks? Measure Analyze Modify
UCB Why Smart Networks? Before: “Simple Network” IP Transport Applications Transport Applications Client Server Network
UCB Why Smart Networks? (continued) Now: “Complex Network” Network Application Servers, Content Servers Caches, Traffic Shapers, Redirection Agents, Processing
UCB Why Smart Networks? (continued) Simple Network: IP Forwarding Routing Table Updates DNS Intelligence in Hosts Complex Network: New Functions New Transport Services (e.g., CoS, SLAs) Needs Intelligence in Network
UCB Why Smart Networks? (continued) INTERNET IP LANs, ATM,... Applications Success of SimplicitySuccess of Complexity TELEPHONE SS7, Billing,... OC-n, DS-n, UTP Applications
UCB Why Smart Networks? (continued) Probably not very desirable! INTERNET IP LANs, ATM,... Applications
UCB Why Smart Networks? (continued) INTERNET IP LANs, ATM,... Applications IP LANs, ATM,... Applications M/A/M Tools for Planning, Design, Operations
UCB Tools for Smart Networks Project Joint UCB - Cisco Project DARPA Funding + Cisco Combines Measurements Analysis & Simulation Real-time Control Objective: Product
UCB Tools for Smart Networks Project (cd) Utility Comprehension Simulations Measurements Analysis Integrated Tools
UCB Tools for Smart Networks Project (cd) Cisco: David Jaffe (Lead Investigator) Karl Auerbach (Lab Design and Implementation) Anna Charny (MPLS) UCB Anantharam, Tse, Varaiya, Walrand Stavros Tripakis (post-doctoral scholar) About 6 graduate students TEAM:
UCB Example 1: DiffServ Goal: CoS without per-connection state No route-pinning Planning and operations based on aggregate statistics and worst-case routing Peer-to-peer SLAs that specify total rate but not traffic destination Solution:
UCB Example 1: DiffServ (continued) Cloud 2 Cloud 1 Policing Shaping SLA
UCB Example 1: DiffServ (continued) Ingress 1 Ingress 3 Ingress 1 Ingress 2 Ingress 3 Typical Case Worst Case Ingress 2 Bottleneck Link DiffServ SLA: Worst Case Admission Control Terribly wasteful!
UCB Example 1: DiffServ (continued) New Admit if peak(new) < Gap at all times Capacity Mean + 2.4s Gap DiffServ SLA: Measurement-Based Admission Control
UCB Example 1: DiffServ (continued) How well does this approach work? Simulation study: Construct traffic model (parametric FBM) Validate model against measurements Simulate admission control policy Test fraction of SLAs that see congested links and level of congestion Experimental study (coming year) Implement measurements and admission control Evaluate performance
UCB Example 2: Bandwidth Allocation Problems: How to share bandwidth How to renegotiate SLAs Issues: Scalability Efficiency Fairness, Optimality,...
UCB Example 2: Bandwidth Allocation (cd) Proposed Adaptation Scheme: Renegotiate “blocks” of permits based on thresholds
UCB Example 2: Bandwidth Allocation (cd) Implementation Peer-to-peer negotiation between bandwidth brokers Two versions Shadow prices Actual pricing
UCB Example 2: Bandwidth Allocation (cd) How well does this approach work? Simulation study: Birth/Death Model of Bandwidth Study Efficiency vs. Rate of Renegotiation