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An introduction to the group and its projects Tony McGregor tonym@wand.nz

An introduction to the group and its projects Tony McGregor tonym@wand.net.nz. WAND Projects. CRCNet Active Measurement IP Measurement protocol Passive Measurement Simulation Integrated measurement and simulation Emulation Network Physical layer switch IPv6

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An introduction to the group and its projects Tony McGregor tonym@wand.nz

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  1. An introduction to the group and its projects Tony McGregor tonym@wand.net.nz

  2. WANDProjects • CRCNet • Active Measurement • IP Measurement protocol • Passive Measurement • Simulation • Integrated measurement and simulation • Emulation Network • Physical layer switch • IPv6 • topology, mobile stacks, fast handover • NZNOG ‘04

  3. CRCNetIntroduction • Project started almost 2 years ago • Rural communities were frustrated by low speed unreliable Internet access • Develop a new platform suitable to deploy future generation (>>10Mbps) wireless networks in rural and remote areas • based around a mesh architecture • Funded by Foundation for Research Science and Technology

  4. CRCNetArchitecture

  5. CRCNetStage 1 – Build Trial Network Range of equipment • 2.4Ghz (802.11b and g) • Orinoco radio cards and APs • Advantech and Soekris Biscuit PC • Linksys wireless Ethernet bridges • 5.8 GHz • Proxim Quick bridge20 • Trango

  6. Current Topology

  7. CRCNetPirongia Site

  8. CRCNetHSK Site

  9. CRCNetMFR Site

  10. Between Hamilton Zoo and the Fieldays site 6 wireless links CRCNetWeb Casting

  11. CRCNetStage Two – Platform Design • Routing protocols for mesh networks • Link Layer Design • Design of a new node

  12. AMPIntroduction • NLANR’s active measurement project • Approx 140 monitors, mostly in the USA. • International deployments • a single AMP monitor in about a dozen other countries • some national AMPs (Australia, Taiwan, Russia soon) • Measure • RTT • loss • topology • throughput (on demand) • NSF funded

  13. AMPUSA Sites

  14. AMPArchitecture

  15. AMPDemo

  16. AMPDemo

  17. AMPDemo

  18. AMPDemo

  19. AMPDemo

  20. AMPDemo

  21. AMPDemo

  22. AMPDemo

  23. AMPCost vs Function • Design • dedicated machines • 1ms accuracy • No GPS/CDMA • 1 sample per minute • Benefits • easy and cheap => wide deployment • full mesh • manageable • Limits • no one-way delays (bidirectional traceroute, IPMP OWD) • very short events missed

  24. AMPManagement

  25. AMPNew Zealand • Beginnings of a New Zealand AMP mesh • Waikato • Auckland • APE • Ihug (offer) • Can fund more monitors and maintenance • need hosts (here?) • hosts provide space, power and network

  26. IPMPIntroduction • Current active measurement protocols have weaknesses • multiple packets (overhead, phantom routes) • measurement of components (reverse path, CPU) • IPMP combines path and delay measurement in a single packet exchange with low router overhead

  27. IPMPArchitecture

  28. IPMPProtocol (IPv4)

  29. IPMPTimestamps • Router can use any timestamp it has available • Resolving to real-time is not done in the packet forwarding critical path • Uses a separate packet exchange (information request/reply) • supplies real-time reference points • other router information

  30. IPMPInformation Reply

  31. IPMPUses • POM made better • combined path and latency, no phantom routes etc • lower overhead • kernel based timestamps • explicit clock information • forward and reverse traceroute • DoS resistant • associates router interfaces • One way delay from NTP • Bandwidth Estimation • Deployment (AMP, CRCnet)

  32. Passive MeasurementOverview • To support simulation work the group developed passive header capture hardware. • Known as Dag cards • Speeds from Ethernet to OC48 (2.5Gbps WAN) • Spun off a startup • Endace (www.endace.com) • now OC192 • better support

  33. Passive MeasurementDag Overview • Capture IP headers or full packet • Add accurate timestamp • GPS or CDMA for external time • Originally header trace focused • real-time flow based • security applications • Optical splitter, electrical card relay or electrical tap

  34. Passive MeasurementDag 3 block diagram

  35. PassiveDag 4.2

  36. PassiveWITS Traffic Archive • Long traces from Auckland University and NZIX • traces up to 45 days (3.2 billion packets) • IP headers • GPS timestamps • Some analysis online • Can fetch traces from NLANR • Summary CD

  37. SimulationIntroduction • ATM-TN based • University of Calgary/Waikato partnership • parallel • BSDLite network stack (sort of) • high bandwidth delay, mixed real-time/TCP • NS-2 with FreeBSD stack • new work • network cradle • 802.11b link layer

  38. SimulationExample –TCP splitting

  39. SimulationThe simulation process

  40. SimulationExample –TCP spliting, Network parameters • Bandwidth 34.369Mbps (E3) • Delay 60ms • TCP buffer size • proxy 32767 bytes • servers as measured • MSS as measured • US delay as measured • NZ delay not simulated

  41. SimulationTCP Splitting – a single connection

  42. SimulationIntroduction

  43. SimulationIntroduction

  44. MessimIntroduction • Simulation is only accessible to very large network operators and users • AIM: Make simulation available to medium sized enterprises • Integrate measurement and simulation • FRST funded

  45. MessimIntroduction

  46. MessimProjects • Topology discovery • automated discovery of link layer devices • Traffic Models • further development of specific models (e.g. peer to peer) • generic • Extraction of simulation parameters from traces • Extended range of network stack models • Continuous validation • Hardware flows analysis

  47. MessimNetwork Stack Cradle Mozilla / Bash / KDE / etc. User space Network stack Kernel space FreeBSD 5 kernel

  48. Network Simulator Cradle (~200 functions) User space Network stack MessimNetwork Stack Cradle

  49. MessimGeneric models • 2d Empirical distribution

  50. MessimGeneric models

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