INCITE – Edge-based Traffic Processing for High-Performance Networks

1. INCITE –Edge-based Traffic Processingfor High-Performance Networks R. Baraniuk, E. Knightly, R. Nowak, R. Riedi Rice University L. Cottrell, J. Navratil, W. Mathews SLAC W. Feng, M. Gardner LANL web site: incite.rice.edu

2. INCITE Project • InterNet Control and Inference from The Edge on-line tools to characterize and map host and network performance as a function of time, space, application, protocol, andservice INCITE Project – Rice, SLAC, LANL

3. INCITE Thrusts and Tools Thrust 1:Multiscale traffic analysis and modeling techniques • wavelet, multifractal, connection-level models Thrust 2:Inference and control algorithms for network paths, links, and routers • end-to-end path probing and modeling • network tomography and topology discovery • advanced high-speed protocols Thrust 3:Data collection tools • active measurement infrastructure • passive application-layer measurement INCITE Project – Rice, SLAC, LANL

4. pathChirp • Goal • estimate instantaneous available bandwidth (ABW) on an end-to-end network link • Basic probing paradigm • stream packets at some rate • no queuing delay  rate<ABW • queuing delay builds up  rate>ABW • Until now: tradeoff • high accuracy has required high volume probing (inefficient) • Unique to pathChirp • variable rateprobe packet train (exponentially spaced chirp) • 10x more efficient than competing techniques INCITE Project – Rice, SLAC, LANL

5. Network Tomography From end-to-endmeasurements… … infer internal topology and delay/loss characteristics INCITE Project – Rice, SLAC, LANL

6. TCP - Low Priority TCP alone 745.5 Kb/s TCP plus 739.5 Kb/sTCP-LP109.5 Kb/s TCP-LP is invisible to TCP • Goal • utilize excess bandwidth in a non-intrusive fashion • Methodology • sender-side modification of TCP: delay-based approach • Applications • bulk data transfers • available bandwidth monitoring • P2P file sharing • High-speed TCP-LP • TCP-LP + HSTCP • implementation • Linux-2.4.22-web100 • experiments • Stanford - Ann Arbor • Stanford - Gainesville INCITE Project – Rice, SLAC, LANL

7. Advanced TCP stacks • Standard TCP (Reno) has problems on today’s long-distance high-speed networks (e.g. trans ocean/continent > hundreds of Mbits/s) • Advanced TCP stacks (e.g. FAST, High-speed, TCP-LP …) and new rate based UDP transports address this issue • We have evaluated many (~10) new implementations for throughput, stability, fairness, ease of use etc. • BaBar (HENP) tier A sites (e.g. SLAC, IN2P3 (Lyon Fr) and FZK (Karlsruhe))now starting to use chosen TCP stack for production transfer of Monte Carlo data to SLAC • Easier to use than multi-stream TCP, only optimize one parameter (window size) INCITE Project – Rice, SLAC, LANL

8. Changes in network topology (BGP) can result in dramatic changes in performance Hour Samples of traceroute trees generated from the table Los-Nettos (100Mbps) Remote host Snapshot of traceroute summary table Note: 1. Caltech misrouted via Los-Nettos 100Mbps commercial net 14:00-17:00 2. ESnet/GEANT working on routes from 2:00 to 14:00 Drop in performance (From original path: SLAC-CENIC-Caltech to SLAC-Esnet-LosNettos (100Mbps) -Caltech ) Back to original path Dynamic BW capacity (DBC) Changes detected by IEPM-Iperfand AbWE Mbits/s Available BW = (DBC-XT) Cross-traffic (XT) Esnet-LosNettos segment in the path (100 Mbits/s) ABwE measurement one/minute for 24 hours Thu 9 Oct 9:00am to Fri 10 Oct 9:01am INCITE Project – Rice, SLAC, LANL

9. Crossing the Application/Network Divide Send data over network Application Segmentation TCP Flow & Congestion Control • Implications to the • application? • Insights for high- • performance network • protocols? Checksums IP Fragmentation : : Data Link Network monitors focus here. Network INCITE Project – Rice, SLAC, LANL

10. TICKET and MAGNET+MUSETICKET: Traffic Information-Collecting Kernel with Exact TimingMAGNeT: Monitor for Application-Generated Network TrafficMUSE: MAGNET User-Space Environment MUSE M A G N E T TICKET: tcpdump++ Send data over network Application Segmentation TCP Flow & Congestion Control Checksums IP Fragmentation : : Data Link Network For more information, go to www.lanl.gov/radiant/pubs.html INCITE Project – Rice, SLAC, LANL

11. MAGNeT  MAGNETMonitoring Apparatus for General kerNel-Event Tracing (at nanoscale granularity) • Why not extend monitoring to kernel events in general? Software Oscilloscope for Cluster and Grids • Debugging • e.g., IdentifiedLinux OS bug in the scheduler for SMPs. • Can be used to deploy, debug, and monitor the DOE UltraNet (UltraScienceNet), e.g., dynamic provisioning. • Performance Optimization • Improved performance of 10GigE adapters by 300%. Can improve end-to-end performance of DOE UltraNet. • Monitoring Grid Applications • Integrated MAGNET with SciDAC’s PERC TAU and SciDAC’s PERC SvPablo/Autopilot.* • Adaptive Resource-Aware Applications • SciDAC Deployment: PERC, Supernova Science Ctr, Transit Network Fabric + Terascale Supernova Initiative + Fusion Energy (emerging), and Earth Systems Grid II (emerging). * For more information, see M. Gardner, W. Deng, T. Markham, C. Mendes, W. Feng, and D. Reed, “A High-Fidelity Software Oscilloscope for Globus,” GlobusWorld 2004, Jan. 2004. INCITE Project – Rice, SLAC, LANL