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Internet2 QoS: Overview and Early Experiences

Internet2 QoS: Overview and Early Experiences. Russ Hobby <rdhobby@internet2.edu> December 4, 2000 Campus Focused Workshop on Advanced Networks. How We Got Here (short version). Began chanting: “enable advanced applications,…” Assessed requirements Recommended DiffServ

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Internet2 QoS: Overview and Early Experiences

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  1. Internet2 QoS: Overview and Early Experiences Russ Hobby <rdhobby@internet2.edu> December 4, 2000 Campus Focused Workshop on AdvancedNetworks

  2. How We Got Here (short version) • Began chanting: “enable advanced applications,…” • Assessed requirements • Recommended DiffServ • Selected “Premium” service to meet demands of loss/jitter sensitive apps • Charted QBone initiative • Specified QBone architecture • Now proceeding to implement it and tweak the architecture architecture deployment Internet2 QoS: Overview and Experiences—Campus Focused Workshop on Advanced Networks (December 4, 2000)

  3. Internet2 QoS Milestones1/2 Jun 1998 Jun 1997 Jun 1999 Jan 1999 Jan 1998 Jan 2000 Bay WorkshopQoS WG DiffServRecommendation Early Internet2 QoS requirements gathering QIG opened QBone CFP RTP QIG Evanston QIG QPS demonstrated (nM demo) QBone initiative launched Las Cruces QIG BBop QCon PittsburghQBone BOF APS Test Program launched QBone architecture draft (v1.0) QBone Forum launched QUALIT Houston I2/DOE QBone Workshop QBone architecture “last call” Internet2 QoS: Overview and Experiences—Campus Focused Workshop on Advanced Networks (December 4, 2000)

  4. Internet2 QoS Milestones2/2 Jun 2000 Jan 2001 TorontoQoS BOF You are here! SC2K QBone demo WG re-chartering Internet2 QoS: Overview and Experiences—Campus Focused Workshop on Advanced Networks (December 4, 2000)

  5. IntServ/RSVP vs DiffServ IntServ/RSVP • Per-flow service state at every hop • Scalability problems • Focus on multipoint multicast BB BB DiffServ • Abstract/manage each cloud’s resources (BBs) • Packets colored to indicate forwarding “behavior” • Focus on aggregates not individual flows • Policing at edge to get services Internet2 QoS: Overview and Experiences—Campus Focused Workshop on Advanced Networks (December 4, 2000)

  6. DiffServ Overview • Applications contract for specific QoS profiles • Policing at network periphery • “Color” packets with a few simple, differentiated per-hop forwarding behaviors (PHBs) • Indicated in packet header • Applied to PHB traffic aggregates • PHBs + policing rules = range of services • DS domains contract with each other for aggregate QoS traffic profiles • Policing at cloud-cloud boundary • Supports simple, bilateral business agreements • Exploits edge/core distinction for scalability Internet2 QoS: Overview and Experiences—Campus Focused Workshop on Advanced Networks (December 4, 2000)

  7. Example Service #1: Premium • Assurance: like a leased line • PHB: Expedited Forwarding (RFC 2598) • EF in separate queue configured with minimum departure rate • Example mechanisms: strict priority, MDRR, WFQ • Policing: police to a specified peak rate and drop out-of-profile packets; effectively a leaky bucket with depth 1 MTU Internet2 QoS: Overview and Experiences—Campus Focused Workshop on Advanced Networks (December 4, 2000)

  8. Example Service #2: Controlled Load • Assurance: network looks “lightly-loaded” for conforming traffic • PHB: Assured Forwarding (RFC 2597) • 4 independent AF classes • 3 drop preference levels within each class • Example mechanisms: WRED, WFQ • Policing: police to specified rate and burst profile, remarking out-of-profile packets to have higher drop probability Internet2 QoS: Overview and Experiences—Campus Focused Workshop on Advanced Networks (December 4, 2000)

  9. Example Service #3: CoS • Assurance: “better than Joe” • PHB: “drop the lower classes first ” (AF or class selector PHBs) • Policing: could be based on anything (e.g. higher priority for the CEO) • A.K.A.“Olympic” classes of BE service (e.g. Gold, Silver, Bronze) Internet2 QoS: Overview and Experiences—Campus Focused Workshop on Advanced Networks (December 4, 2000)

  10. QBone Architecture • A Service: QBone Premium Service • Built on Expedited Forwarding (EF) (RFC 2598) • Assurance: near-zero loss & low, bounded jitter for marked traffic conforming to a specified peak rate • a.k.a. “virtual leased line”, “virtual wire” • Reservation Setup Protocol • Now: long-lived, manual setup • Proposed: SIBBS protocol between QBone domains; RSVP end-to-end between hosts • QBone Measurement Architecture • Uniform collection of QoS metrics • Uniform dissemination interface Internet2 QoS: Overview and Experiences—Campus Focused Workshop on Advanced Networks (December 4, 2000)

  11. QBone E2E Picture X Kbps of QPS from hither to………..yon CampusA CampusB Campus C CampusD GigaPoPA GigaPoPB Backbone Key Internet2 QoS: Overview and Experiences—Campus Focused Workshop on Advanced Networks (December 4, 2000)

  12. Abilene Premium Service (APS) • Goal: • Make APS a reference implementation of the QBone architecture • Why? • Catalyst: Enable wide-area QoS experimentation and propagate Abilene’s experiences to larger community • Safety Belt: Congestion is only one success catastrophe away! • The Team: • UCAID • Indiana University • I-TECs (NCNI, OARnet) • NLANR/NCNE • Cisco • Qwest • Nortel Internet2 QoS: Overview and Experiences—Campus Focused Workshop on Advanced Networks (December 4, 2000)

  13. APS Participation • Participation Criteria • Abilene connector status necessary but not sufficient • QBone participation • Capability of access router / Abilene edge card • Current Participants • MAGPI (U. Penn) • iCAIR • PSC (Penn State) • OARNet (Ohio State) • Others in the wings • NASA EOS • Various international • ANL • UIUC • DOE Science GRID (peering transit network) Internet2 QoS: Overview and Experiences—Campus Focused Workshop on Advanced Networks (December 4, 2000)

  14. Initial Engineering Plan (obsolete) Sweetwater Midland Odessa Pecos Measurement Edge Policing Manual Setup EF Core Forwarding EF Edge Forwarding (MDRR) (BB) Shaping (Surveyor + SNMP + HTTP) (“Firehose” CAR) (Whiteboard + CLI) (MDRR) Automated Setup (GTS) Internet2 QoS: Overview and Experiences—Campus Focused Workshop on Advanced Networks (December 4, 2000)

  15. APS Phase 1: “Sweetwater” • First, crawl… • Ingress policing • Measurement feedback • Limited technical support • No priority queuing yet, but still get benefit of Abilene’s over-provisioning! • Goals • Begin to establish operational practices for responding to admissions requests • Provide participants with the experience of sitting behind a policer Internet2 QoS: Overview and Experiences—Campus Focused Workshop on Advanced Networks (December 4, 2000)

  16. APS Measurements • Goal: implement QBone measurement architecture (collection + dissemination) for a single QBone domain • Hoped-for Side Effects: • Tools to ease implementation for others • Adjustments to QMA based on implementation experiences Internet2 QoS: Overview and Experiences—Campus Focused Workshop on Advanced Networks (December 4, 2000)

  17. Committed Access Rate (CAR) • Classifies traffic based on certain matching criteria and meters it to a leaky bucket traffic profile • Depending on metering result, different actions applied (drop, transmit, set DSCP,…) • Syntax: • rate-limit {input | output} [access-group [rate-limit] acl-index] bps burst-normal burst-maxconform-actionactionexceed-actionaction Internet2 QoS: Overview and Experiences—Campus Focused Workshop on Advanced Networks (December 4, 2000)

  18. CAR Experience • For the most part, CAR is exactly what the DiffServ doctor ordered • However, there are some limitations… • Performance • Token bucket depth • Classification of DiffServ aggregates Internet2 QoS: Overview and Experiences—Campus Focused Workshop on Advanced Networks (December 4, 2000)

  19. CAR Limitation 1: Performance • On E0 edge cards, no ASIC support for CAR •  there is a performance hit pps @ 256 bytes * Preliminary E0 CAR performance figures under retest by ITEC-NC Internet2 QoS: Overview and Experiences—Campus Focused Workshop on Advanced Networks (December 4, 2000)

  20. Addressing CAR Performance • Out of our hands • The Plan: • Load on access interfaces is still light, so performance not really an issue for now • Wait for E3 edge cards, which will have CAR in hardware Internet2 QoS: Overview and Experiences—Campus Focused Workshop on Advanced Networks (December 4, 2000)

  21. Virtual Trunk vs.“Firehose” Classification • What we want... • What we have now... • The good news: CAR can also classify by: • qos-group (Cisco proprietary concept) • With packets assigned to QoS groups through QoS Policy Propagation via BGP (QPPB) Internet2 QoS: Overview and Experiences—Campus Focused Workshop on Advanced Networks (December 4, 2000)

  22. Abilene Architecture Limitation: “Porous” Edge Problem • QoS theft problem with current architecture • MDRR (EF forwarding) on interior interfaces easily subverted by unpoliced connectors Internet2 QoS: Overview and Experiences—Campus Focused Workshop on Advanced Networks (December 4, 2000)

  23. Current Engineering Plan Sweetwater Midland Odessa Pecos Measurement Edge Policing Manual Setup EF Core Forwarding EF Edge Forwarding (MDRR) Automated Setup (DBP-TE? + BB) Shaping (Surveyor + SNMP + HTTP + WHOIS + traffic matrices) (CAR + QPPB + PIRC filtering?) (Whiteboard + CLI) (MDRR) (GTS) Internet2 QoS: Overview and Experiences—Campus Focused Workshop on Advanced Networks (December 4, 2000)

  24. SC2000 Interdomain QoS DemoNovember 6-9, 2000 • Premium service over two wide-area paths • LBNL-ESnet-Abilene-SCinet-Internet2 booth • Stanford-CalREN2-Abilene-SCinet-Internet2 booth • Congestion induced at multiple points • CD-quality interactive audio application shown with/without QoS • ESnet and Abilene QoS capabilities formed nucleus of QBone • SC2000 Network Challenge Winner: "Most Captivating and Best Tuned Award" Internet2 QoS: Overview and Experiences—Campus Focused Workshop on Advanced Networks (December 4, 2000)

  25. ALS ExtremeSummit1i ExtremeSummit1i OC-48 POS Abilene Core stan.calren2 qsv.calren2 SmartBits CCRMA Audio Access Edge NetCom X-PortCrystallography NetworkMonitoring CCRMAAudio GARA Cisco 12008 Cisco 12008 Cisco 7505 Cisco 7505 IPLS-QOS ANL-TB1 SND-GW LBL-TB1 Q-GW Cisco 7505 Cisco 7505 Cisco 7505 Cisco 7505 Cisco 7505 SmartBits 200 Interdomain Quality of Service Demo OC-12 10 Mbps OC-3 GE GE ESNet/DOE Science Grid Devicecontrol OC-12 OC-12 LBNL CalREN2 Abilene OC-48 OC-12 I2-GWCisco 12008 core-confCisco 12008 OC-3 SCinet OC-3 Traffic Generators Internet2 SC2000 Booth Stanford University = congestion + QoS control * All links 100Mbps fast Ethernet (FE) unless otherwise noted Internet2 QoS: Overview and Experiences—Campus Focused Workshop on Advanced Networks (December 4, 2000)

  26. Deployment • Good News: • DiffServ functionality in most modern routers • Many hosts support QoS signaling • Lots of isolated testbed trials • Some partial backbone implementations • Bad News: • Weak demand • Turnkey solutions are a long way off • Vendor implementations don’t always live up to hype • HR scarcity • Bottom line: • Progress can be made, but it takes a lot of people, time, and effort Internet2 QoS: Overview and Experiences—Campus Focused Workshop on Advanced Networks (December 4, 2000)

  27. Going Forward • Need increased focus on low-hanging fruit • Less than Best-Efforts (LBE) • Ad-hoc CoS at congestion points • Basic LBE idea • Low-priority traffic class • Agree on an Internet2 LBE code point • Benefits • Traffic management • License to hog (some users are self-policing) • New advanced applications (e.g. large scale distributed computation) • It’s easy! Internet2 QoS: Overview and Experiences—Campus Focused Workshop on Advanced Networks (December 4, 2000)

  28. Starvation: Making LBE Stronger • Define “starvation class selector” (SCS) • An SCS packet MUST never consume a network resource desired by a non-SCS packet • Corollary 1: there must not be a configured minimum departure rate for SCS traffic • Corollary 2: all queued SCS packets must be evicted before a forwarding element can drop a non-SCS packet (probably difficult to implement) • Result: it’s the dual of EF! Internet2 QoS: Overview and Experiences—Campus Focused Workshop on Advanced Networks (December 4, 2000)

  29. Any Questions? Internet2 QoS: Overview and Experiences—Campus Focused Workshop on Advanced Networks (December 4, 2000)

  30. For more information... • Internet2 Home: • http://www.internet2.edu/ • Internet2 QoS Working Group Home: • http://www.internet2.edu/wg/qos/ • QBone Home: • http://qbone.internet2.edu/ • Abilene Premium Service Home: • http://www.internet2.edu/abilene/qos/ Internet2 QoS: Overview and Experiences—Campus Focused Workshop on Advanced Networks (December 4, 2000)

  31. Internet2 QoS: Overview and Experiences—Campus Focused Workshop on Advanced Networks (December 4, 2000)

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