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PingER : Actively measuring the worldwide Internet’s end-to-end performance. Les Cottrell SLAC MYREN meeting, Kuala Lumpur December 12, 2012. Agenda. Using PingER measurements going back to 1998 and covering 168 countries, this talk will illustrate, Internet performance worldwide.
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PingER: Actively measuring the worldwide Internet’s end-to-end performance Les CottrellSLAC MYREN meeting, Kuala Lumpur December 12, 2012
Agenda Using PingER measurements going back to 1998 and covering 168 countries, this talk will illustrate, Internet performance worldwide. • Brief history • How can the Internet help development? • How does PingER measure Internet performance? • What do we measure, what does it tell us? • What do we find? • Case studies illustrating PingER
History • Story of Ping • Early PingER • Extension to Developing Regions • Extension to Pakistan • Extension to Malaysia
The start • Ping tool invented by Mike Muus • “a little thousand-line hack” during a single evening to troubleshoot “odd behavior” on the computer network at the U.S. Army’s Ballistic Research Laboratory in Maryland. • sent a small data packet known as an echo request to an IP address, typically a remote server or network node. If the target address was reachable, it echoed back the same data, and the program recorded the time it took for the round-trip journey. • Reminded Muuss of the percussive sound pulse sonar systems use to detect objects underwater, he named it after that sound—ping.
Measurement Mechanism: PingER >ping remhost Monitor Host Internet 10 ping request packets each 30 mins Remote Host (typically web server) Ping response packets Measure Round Trip Time & Loss Joint Techs: I2 & ESnet, Stanford
Early PingER • As the head of networking at SLAC, I set up the system using ping simply to test connections between the laboratory and several dozen research institutions in about a dozen countries that were collaborating on a physics experiment known as BaBar to study properties of subatomic particles. • Over the next half-decade, as word of PingER’s value spread, I extended monitoring to hundreds more physics laboratories and science centers across the globe. But the project didn’t take a humanitarian turn until 2001. UNIMAS Workshop, Sarawak, Dec 2012
Extension to the Developing regions • In 2001 I visited ICTP in Italy. • Driven by ICTP’s goals of bringing first-class science and technology to developing countries they wanted to know how well the networks were working. • The simple PingER project was the perfect tool for the job. Ubiquitous ping so nothing to install at remote targets. • They offered to help expand the project to those parts of the world that needed it most. • Within the next year, we began establishing monitoring and target hosts in countries as diverse as Ecuador, Rwanda, Jordan, and Bhutan. UNIMAS Workshop, Sarawak, Dec 2012
Extension to Pakistan • In 2004 set up joint agreement with NUST in Pakistan • Soon got my first real glimpse of just how much of a difference PingER can make. • Set up a PingER monitoring site in the country to assess performance on the then year-old Pakistan Educational Research Network (PERN). • The network’s providers touted its bandwidth of 155 Mbps, impressive at the time. But PingER revealed that the “last mile” links to universities were dreadful. These bottleneck connections funneled data at no more than 1 Mbps, causing long delays and high packet loss. UNIMAS Workshop, Sarawak, Dec 2012
Extension to Pakistan • During a visit to the university, I presented our findings to the chairman of Pakistan’s higher education commission, Atta-ur-Rehman, who was preparing to fund the next major upgrade to PERN. • He clearly took PingER’s lessons to heart. When construction of PERN2 began in 2009, its plans included extending high-speed, 1-Gbps data links all the way to university data centers UNIMAS Workshop, Sarawak, Dec 2012
Extension to Malaysia • Have set up an official signed MoU between SLAC & U of Malaysia in Sarawak (UNIMAS) • Idea was to replicate the NUST project • Fortnightly meetings by Skype • Just getting started, no students yet • Met with Vice Chancellor (VC) at one meeting • This workshop is a follow up. UNIMAS Workshop, Sarawak, Dec 2012
Why do measurements of the Internet matter UNIMAS Workshop, Sarawak, Dec 2012
Why does it matter • African scientists isolated • Lack critical mass • Need network to collaborate but it is terrible • Brain drain • Brain gain, tap diaspora • Blend in distance learning • Provide leadership, train trainers Tertiary Education from http://www.worldmapper.org/ Cartograms from: www.geog.qmw.ac.uk/gbhgis/conference/cartogram.html 12 Internet Users 2002
How does the Internet help • Investment in information technology plays the role of a "facilitator" that allows other innovations to take place.http://findarticles.com/p/articles/mi_m1093/is_3_45/ai_86517828/ • World Bank / IFC report: for every 10% increase in high-speed Internet connections there is an increase in economic growth of 1.3 percentage points. April 2010. http://www.infodev.org/en/Article.522.html • Example: Uganda 15% increase in price of maize based on improved farmer bargaining power. www.itu.int/ITU-D/.../S1-01-NG-ICT_Indicators-Tim_Kelly.pptx eGY Africa 2012 Workshop, Nairobi Oct 2012
How does PingER work • Mechanism • Coverage UNIMAS Workshop, Sarawak, Dec 2012
Measurement Mechanism: PingER >ping remhost Uses ubiquitous ping Monitor Host Internet 10 ping request packets each 30 mins Remote Host (typically web server) Once a Day NUST Ping response packets Repositories Measure Round Trip Time & Loss Joint Techs: I2 & ESnet, Stanford
Deployment • Beacons monitored by most monitors (~100) • Monitors > 90 in 23 countries, 4 in Africa • Remote sites monitored by some monitors (~750) Summer Joint Techs Stanford, July 2012
Metrics Available from PingER • UnReachability • Minimum RTT • Average RTT • Jitter • Loss • Derived throughput • MOS • Directness of Connection • Others UNIMAS Workshop, Sarawak, Dec 2012
Unreachability: e.g. N. African uprisings Jan ‘11 Unreachability =No pings respond NARSS (Cairo) 23:59 Jan 27 Helwan (Cairo) 12:00 Jan 27 EUN (Cairo) 23:59 Jan 28 • Impact varied: start time, recovery time, after effects • Egypt University Network (EUN) down least time • NARSS via Alternet->Italy->Egypt, Helwan &EUN via PCCW Global • Libya first went dark 06:00 Feb 19 for 3 days, then again on Mar 4th more permanently • Algeria, Morocco, Tripoli not noticeable eGY Africa 2012 Workshop, Nairobi Oct 2012 Summer Joint Techs Stanford, July 2012
Average Round Trip Time (RTT) • Mainly a distance related, but also congestion (i.e. at the edge) • For real-time multimedia (H.323) traffic RTT: 0-300ms =Good, 300-600ms=Accceptable, and > 600ms= poor. UNIMAS Workshop, Sarawak, Dec 2012
Minimum RTT history by region • Minimize effects of congestion and queuing UNIMAS Workshop, Sarawak, Dec 2012
GEOS (Geostationary Earth Orbit Satellite) • Good coverage, but expensive in $/Mbps • & long delays min RTT >450ms easy to spot Impact of GEOS vs Terrestrial N.b. RTTs > 250 ms bad for VoIP GEOS UNIMAS Workshop, Sarawak, Dec 2012
Conversion history by country seen by min-RTT UNIMAS Workshop, Sarawak, Dec 2012
Jitter • Mainly at edges, critical for real time: VoIP, gaming • Exponential improvement (factor 10 in 6 yrs) • The optimum amount of one way latency is 11 ms for keeping time in music. • Above that delay and they tend to slow down. • >50-70 ms performances tended to completely fall apart. • For real time haptic control and feedback for medical operations <=80ms is needed. N. America, Europe, E Asia & Oceania < 1ms Africa, S. Asia & S.E. Asia worst off UNIMAS Workshop, Sarawak, Dec 2012
Losses Loss • Low (<1%) losses are good. • Real time impact due to recovery timeouts, e.g. echoing typing • Losses are mainly at the edge, so distance independent • Losses improving roughly exponentially, ~factor 100 in 12 years • Loss has Similar • behavior to thruput • Best <0.1%: N. America, E. Asia, Europe, Australasia • Worst> 1%: • Africa & C. Asia Summer Joint Techs Stanford, July 2012 24
Derived Throughput Europe, E. Asia & Australasia merging Behind Europe: 4 yrs: Russia, 7 yrs:L America, M East, SE Asia 11 yrs: India, C. Asia 13 yrs: Africa Derived throughput ~ 8*1460/(RTT*sqrt(loss)) Mathis et. al UNIMAS Workshop, Sarawak, Dec 2012 Summer Joint Techs Stanford, July 2012
Mean Opinion Score MOS) MOS • ITU metric, based on quality of a conversation • Originally people listen and give quality 1-5 • Can derive from RTT, jitter and loss • >=4 is good, • 3-4 is fair, • 2-3 is poor. Usable Important for VoIP UNIMAS Workshop, Sarawak, Dec 2012 From the PingER project http://www-iepm.slac.stanford.edu/pinger
Directness of connection (Alpha) • Alpha to allow for delays in network equipment & indirectness of actual route. D = 1 way distance • Alpha = D(km) / (min_RTT[msec] * 100 [km/msec]) • If know lat/long of monitor and remote host then know D, so with min-RTT can estimate Alpha • Max(Alpha) =1 = direct (great circle) route and no network delays • Alpha > 1 probably identifies bad lat/long coordinates for hosts. • Low values typically mean very indirect route, or satellite or slow connection (e.g. wireless) • Alpha typically ~ 0.45 UNIMAS Workshop, Sarawak, Dec 2012
Alpha worldwide NSK.RU DE JP 0.32 SLAC EG 0.34 TW 0.18 Alpha=0.71 JP 0.16 IN o.41 AU 0.53 Alpha=0.73 Alpha=0.73 AU NZ • Interest in Polar route with Global warming Summer Joint Techs Stanford, July 2012 UNIMAS Workshop, Sarawak, Dec 2012
Directivity (Alpha) from SLAC to world • Big improvements for C Asia, S Asia & Australasia More stable year to year as add more hosts UNIMAS Workshop, Sarawak, Dec 2012 Summer Joint Techs Stanford, July 2012
Other metrics • Duplicate packets (try ping www.cern.ch, load balancing?) • Out of order packets (parallel paths) • Conditional Loss Probability (non-random loss) • one packet is lost the following packet is also lost • route change, loss of sync, spanning tree reconfig • Maximum packet loss (useful for buffer bloat?) UNIMAS Workshop, Sarawak, Dec 2012 Summer Joint Techs Stanford, July 2012
More Information • PingER web home page • http://www-iepm.slac.stanford.edu/pinger/ • Tutorial on network monitoring • http://www.slac.stanford.edu/comp/net/wan-mon/tutorial.html • PingER data Explorer • www-iepm.slac.stanford.edu/pinger/explorer.html • Telegeography submarine cable map • http://www.submarinecablemap.com/ UNIMAS Workshop, Sarawak, Dec 2012
S.E. Asia • Just started mining early data • Where does Malaysia sit • How much variation in SE Asia • Variation in Malaysia • Troubles at UNIMAS • Top and bottom 3 sites monitored in Malaysia UNIMAS Workshop, Sarawak, Dec 2012
Malaysia vs Other Regions UNIMAS Workshop, Sarawak, Dec 2012
Variation between SE Asian countries • Factor of 10 between Singapore and Laos • Singapore 4x better than next countries • Exponentially improving with time • On its ownSingaporeapproachesE Asia. UNIMAS Workshop, Sarawak, Dec 2012
Avg-RTT, jitter & loss by Malay State • Need low values of all 3 metrics • RTTs similar, big diffs in jitter & loss • AllianzeUniColl looks bad • UTP next worst loss Seen from SLAC, Nov 2012 UNIMAS Workshop, Sarawak, Dec 2012
Non lossy Malaysian hosts seen from SLAC Nov 2012 UNIMAS MIMOS MIMOS UNISZA Note monitoring host (SLAC) down UNIMAS Workshop, Sarawak, Dec 2012
Lossy host seen from SLAC Nov 2012 UTEM MIU UPSI OCESB AIU Sabah UNIMAS Workshop, Sarawak, Dec 2012
Diving deeper: packet loss Nov 27-28 • Allianze University College unreachable • UTEM, MIU, UPSI, OCESB, AIU, SABAH experienced loss Nov 26 • No PingER loss from the rest on Nov 26: Johor, Kelantan, KL, Negeri Sembian, Sarawak, Terenggan 1930-midnight MST, backup? Losses isolated, not correlated with large RTT UTEM UNIMAS Workshop, Sarawak, Dec 2012
Another host, large RTTs correlate with time of day (note MST) UNIMAS Workshop, Sarawak, Dec 2012
UNIMAS Jitter Allianze University College UNIMAS to Malaysia Jitter UniversitiTechnologi Petronas UNIMAS Workshop, Sarawak, Dec 2012
Why not show UNIMAS to Malaysia more • Big changes in RTT affect throughput especially for Kuching • UNIMAS was seeing congestion • This would be seen everywhere • Turn on shaping • Removes loss &day-night variations SLAC to UNIMAS Oct-Nov 2012 2 RTT ms 1 Background loss colors UNIMAS Workshop, Sarawak, Dec 2012
Increase of capacity to UNIMAS from 200Mbps to 500Mps UNIMAS Workshop, Sarawak, Dec 2012
Improvement UNIMAS Workshop, Sarawak, Dec 2012
Unreachable Malaysian hosts • Unreachable from SLAC Nov 1-26, 2012: • 92% Allianze University College • 20% www.ocesb.com.my (Speedtest) • 17% Universiti Teknologi Petronas,Bandar Seri Iskandar • 4% University Malaysia Kelantan • 100% Reachable • MIMOS, UNIMAS, Sultan Zainal Abidin University, USIM, University Teknologi Malaysia, Sultan Idris University of Education UNIMAS Workshop, Sarawak, Dec 2012
Demo • Interactive demonstrations of the data mining capabilities of public data sources provided by organizations such as the UN and ITU coupled with monitoring data from PingER • http://www-iepm.slac.stanford.edu/pinger/explorer.html Summer Joint Techs Stanford, July 2012 UNIMAS Workshop, Sarawak, Dec 2012
Comparison to UN ITU ICT Development Index 10000 1000 PingER Derived throughput (kbits/sec) 100 Bubble size = Population 4 6 8 2 10 ICT Development Index from the UN International Telecommunications Union UNIMAS Workshop, Sarawak, Dec 2012
More Information • PingER web home page • http://www-iepm.slac.stanford.edu/pinger/ • Tutorial on network monitoring • http://www.slac.stanford.edu/comp/net/wan-mon/tutorial.html • PingER data Explorer • www-iepm.slac.stanford.edu/pinger/explorer.html • Invitation to set up a Monitoting host • www-iepm.slac.stanford.edu/pinger/letters/invite-monitor.doc UNIMAS Workshop, Sarawak, Dec 2012
Congestion at UNIMAS • SLAC to UNIMAS Nov 1st through Dec 6th • Note the diurnal changes until shaping Loss RTT UNIMAS Workshop, Sarawak, Dec 2012