1 / 36

A WAN-in-LAB for Protocol Development

A WAN-in-LAB for Protocol Development. Netlab, Caltech Lachlan Andrew, George Lee, Steven Low(PI), John Doyle, Harvey Newman. Outline. What and why is WAN-in-Lab? What can I do with WiL? Why would I use WiL? How do I use WiL? Future plans. What is WAN-in-Lab?.

nhu
Download Presentation

A WAN-in-LAB for Protocol Development

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. A WAN-in-LAB for Protocol Development Netlab, Caltech Lachlan Andrew, George Lee, Steven Low(PI), John Doyle, Harvey Newman

  2. Outline • What and why is WAN-in-Lab? • What can I do with WiL? • Why would I use WiL? • How do I use WiL? • Future plans

  3. What is WAN-in-Lab? • “Wide Area” Network in a laboratory • Real fibre delays • Carrier-class routers, switches, …

  4. ? DummyNet EmuLab ModelNet WAIL UltraLight PlanetLab Abilene NLR LHCNet CENIC etc NS2 SSFNet QualNet JavaSim Mathis formula Optimization Control theory Nonlinear model Stocahstic model Why -- Spectrum of tools cost abstraction live netwk WANinLab emulation simulation maths All scales are important– WAN-in-Lab fills a gap

  5. What can I do with WAN-in-Lab?

  6. Other groups’ interests • Protocol development • FAST, delay-based • MaxNet, explicit signalling • ADPM, single-bit explicit signalling • Impact of small buffers (U. Pittsburgh) • Test automatic configuration of routers (MonALISA, Ultralight) • Test distributed file-system (MojaveFS)

  7. TCP Benchmarking • Our current main direction • Evaluating others’ protocols, not ours • Web interface • Submit kernel patch • Standard tests automatically performed • Results mailed back • Explicit or implicit signalling protocols

  8. Physical topology

  9. Capabilities: Delay • 24 spools of 100km fibre, many loopbacks • Set delay by MEMS switching loops in/out • 130ms physical delay • more with IP loopback • 2 Dummynets: long delay for cross-traffic 125 ms, 1.8ms steps

  10. External connections • Linked to Ultralight, 10Gbps Physics WAN • Smooth migration testing -> deployment • Delay • longer • jitter • Cross traffic • Monitordata routedthrough WiL

  11. Why use WAN-in-Lab?

  12. Why use WiL? • Complement other levels of abstraction, not replace them • Different ways to use it: reasons for each • Standard platform for TCP benchmarking • Easier to compare with others’ results • No need to write your own test suite

  13. 83 packets Artifacts of software delays • Packets sent on 1ms “ticks” • 1Gbps = 83,333 pk/s 1ms

  14. How can I use WAN-in-Lab?

  15. Management structure

  16. Time sharing • Coarse switching between projects • Servers rebooted, routers reconfigured • Switchover takes ~5 minutes • Book in advance • For longer bookings, book further in advance • Also “ad hoc” bookings for individual hosts • Can log in while others have booked

  17. Future plans

  18. Future plans • Benchmarking infrastructure • Standardise tests • Use it ourselves • Develop “indices” of TCP performance • Better control over capacities and buffers • Better cross-traffic generation • Currently Harpoon • Investigate differences from DummyNet • Integrate DAG cards

  19. Conclusion • WAN-in-Lab fills the gap between emulation and live network experiments • Seeks to be as realistic as possible • Long links, simple topology • Focus will be on TCP benchmarking • We welcome people to use it <http://wil.cs.caltech.edu>

  20. Spare Slides

  21. Case Study: MaxNet

  22. Aim: Wind Tunnel of Networking • WAN in Lab • Capacity: 2.5 – 10 Gbps • Delay: 0 – 120 ms round trip • Breakable • Won’t take down live network • Flexible, active debugging • Passive monitoring, AQM • Configurable & evolvable • Topology, rate, delays, route • Modular design stays up to date • Integral part of R&A networks • Transition from theory, implementation, demonstration, deployment • Transition from lab to marketplace • Global resource • Part of global infrastructure UltraLight led by Harvey Newman

  23. Equipment • 4 Cisco 7609 routers with OC48 line cards • 6 Cisco ONS 15454 switches • A few dozen high speed servers • 1G switch to routers/servers • Calient switch for OC48 • 2,400 kilometres of fibre, optical amplifiers, dispersion compensation modules • 63ms aggregate RTT delay, in two hops • 120ms using IP loopbacks

  24. Accounts • Mail wil at cs.caltech.edu • Sudo access to “network” commands • Ifconfig/…/ • Custom commands to set topologies • Login to routers if required • Separate accounts for “benchmark only”

  25. Configuration -- Delays • Want maximum delay from limited fibre • Signals traverse fibre 16 times • 4 WDM wavelengths • 4 OC48 (2.5G) MUXed onto OC192 (10G) • Lots of transponders • WDM amplifier joins 100km spools  200km

  26. OC48 slot Configuration – delays -------WDM Wavelength-------- 16x200km Amp Bidirectional 100km Bidirectional 100km

  27. Configuration – delays • Delay varied by adjusting the number of OC48 hops traversed • Calient optical switch selects required hops • Hop lengths 200km up to 1600km • Maximise granularity given limited switch ports Switch

  28. Projects • TCP benchmarking • FAST • Delay-based congestion control • MaxNet • Explicit signalling congestion control • MojaveFS • New distributed file system • University of Pittsburgh • TCP with small buffers • University of Melbourne • Single-bit congestion marking

  29. WAN-in-Lab testbed • Dummynet and simulation introduce artifacts • Also need to test on real equipment • WAN with real delays, located in a single room • Connected to an external WAN (Ultralight) • Open for the community to use for benchmarking OC-48 OC-48

  30. WAN-in-Lab capabilities

  31. OC48 slot Configuration -- delays -------WDM Wavelength-------- Amp Bidirectional 100km Bidirectional 100km

  32. Using WAN-in-Lab • Contact me – lachlan at caltech . Edu • Coarse timesharing • Some users set up experiments while others run experiments • Software setup still being developed • Your chance to influence our directions to tailor it to your needs

  33. Sample MaxNet results • Achieves realistic delay at 1Gbit/s

More Related