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Quantifying the need for Improved Network Performance for S. Asia. Prepared by: Les Cottrell SLAC & Shahryar Khan NIIT For the Internet2 Special Interest Group on Emerging NRENs Planning Meeting: Enhancing Research and Education Connectivity to and within South Asia April 26, 2007
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Quantifying the need for Improved Network Performancefor S. Asia Prepared by: Les CottrellSLAC& Shahryar KhanNIIT For the Internet2 Special Interest Group on Emerging NRENs Planning Meeting: Enhancing Research and Education Connectivity to and within South Asia April 26, 2007 http://www.slac.stanford.edu/grp/scs/net/talk07/sasia-case-apr07.ppt
PingER Methodology Uses ubiquitous ping >ping remhost Remote Host (typically a server) Monitoring host Internet 10 ping request packets each 30 mins Once a Day Ping response packets Data Repository @ SLAC Measure Round Trip Time & Loss
PingER Deployment • PingER project originally (1995) for measuring network performance for US, Europe and Japanese HEP community - now mainly R&E sites • Extended this century to measure Digital Divide: • Collaboration with ICTP Science Dissemination Unit http://sdu.ictp.it • ICFA/SCIC: http://icfa-scic.web.cern.ch/ICFA-SCIC/ • >120 countries (99% world’s connected population) • >35 monitor sites in 14 countries • Monitor 44 sites in S. Asia • Most extensive active E2E monitoring in world
World Measurements: Min RTT from US • Maps show increased coverage • Min RTT indicates best possible, i.e. no queuing • >600ms probably geo-stationary satellite • Between developed regions min-RTT dominated by distance • Little improvement possible • Only a few places still using satellite for international access, mainly Africa & Central Asia 2000 2006
Unreachability • All pings of a set fail ≡unreachable • Shows fragility, ~ distance independent • Developed regions US, Canada, Europe, Oceania, E Asia lead • Factor of 10 improvement in 8 years • Africa, S. Asia followed by M East & L. America worst off • Africa NOT improving SE Asia L America M East C Asia Oceania S Asia SE Europe Russia Developing Regions Africa E Asia Developed Regions US & Canada Europe
Losses • Mainly distance independent • Big impact on performance, time outs etc. • Losses > 2.5 % have big impact on interactivity, VoIP etc. • N. America, Europe, E. Asia, Oceania < 0.1% • Underdeveloped 0.3- 2% loss, Africa worst.
Jitter • ~ Distance independent • Calculated as Inter Packet Delay Variation (IPDV) • IPDV = Dri = Ri – Ri-1 • Measures congestion • Little impact on web, email • Decides length of VoIP codec buffers, impacts streaming • Impacts (with RTT and loss) the quality of VoIP Usual division into Developed vs Developing Trendlines for IPDV from SLAC to World Regions C Asia Russia S. Asia Africa SE Asia L. America M East Australasia Europe N. America E. Asia
VoIP & MOS • Telecom uses Mean Opinion Score (MOS) for quality • 1=bad, 2=poor, 3=fair, 4=good, 5=excellent • With VoIP codecs best can get is 4.2 to 4.4 • Typical usable range 3.5 to 4.2 • Calc. MOS from PingER: RTT, Loss, Jitter (www.nessoft.com/kb/50) MOS of Various Regions from SLAC Improvements very clear, often due to move from satellite to land line. Similar results from CERN (less coverage) Usable
World thruput seen from US Throughput ~ 1460Bytes / (RTT*sqrt(loss)) (Mathis et al) Behind Europe 6 Yrs: Russia, Latin America 7 Yrs: Mid-East, SE Asia 10 Yrs: South Asia 11 Yrs: Cent. Asia 12 Yrs: Africa South Asia, Central Asia, and Africa are in Danger of Falling Even Farther Behind
Normalized for Details • Note step changes • Africa v. poor • S. Asia improving • N. America, Europe, E Asia, Oceania lead
“Development” Indices • There are many “development” indices today (values 0-1), e.g.: • UNDP Human Development Index (2006, 177 countries) • UNDP Technology Achievement Index (2001, 72 countries) • ITU Digital Access Index (2003) and the Digital Opportunity Index (2006), both 180 countries • World Economic Forum’s Network Readiness Index (2004, 2005, 2006-2007: 122 countries) • Harvard University Network Readiness Index (2002, 75 countries) … • Typically subset of: GDP/capita, knowledge (e.g. tertiary education enrollment), life expectancy, network (hosts/capita, access, policy, usage, affordability, users/capita); technology (patents, royalties, exports, phones/capita, electricity) • The size of the Internet infrastructure is a good indication of a country's progress towards an information-based economy. • Indices are hard to gather, agree on, many countries do not report • Most Internet traffic in a developing country is international (75-90%) • We measure international Internet performance which is an interesting (good?) indicator.
Digital Access Index (DAI) infrastructure, affordability, knowledge and quality and actual usage of ICTs • Most European countries > 1500 Kb/s throughput and greater than 0.6 DAI. Exceptions: • Malta, Belarus and Ukraine. • Balkans is catching up with Europe, exception Albania is way down. • E. Asia apart from China clusters • M East: Israel & Cyrus close to Europe, Iran way down • SE Asia 3 cluster: Singapore at top, Malaysia and Brunei middle, Vietnam & Indonesia at bottom • S. Asia 2 clusters: • India, Pakistan, Sri Lanka • Bangladesh, Bhutan, Nepal • Africa at bottom • Correlation strong
S. Asia Coverage Min-RTT from CERN • Monitor 44 hosts in region. • 6 Monitoring hosts Loss from CERN
Routing • Between developing countries often use transcontinental links (like Europe in 80’s), e.g.: • Pak to Pak or India to India is direct, however, • Between Pak & India via US or Canada or Europe • Between India or Pak and Bangladesh via US or UK • Wastes costly transcontinental bandwidth • Need International eXchange Points (IXPs)
Bandwidth & Internet use • Note Log scale for BW • India region leader • Pakistan leads bw/pop • Nepal very poor • Pakistan leads % users • Sri Lanka leads hosts%% • Pakistan leads bw/pop • Nepal, Bangladesh, Afghanistan very poor
S Asia MOS & thruput Daily throughputs from US to S Asia • weekend vs. w’day, day vs night = heavy congestion RTT NIIT to QAU Pak (1 week) RTT ms Fr Su Mo Tu Sa We Th Mean Opinion Score to S Asia from US Usable • Last mile problems • Divides into 2 • India, Maldives, Pakistan, Sri Lanka • Bangladesh, Nepal, Bhutan, Afghanistan Pakistan
DAI vs. Thru & S. Asia • More details, also show populations • Compare S. Asia with developed countries, C. Asia
Conclusions • DD exists between regions, within regions, within countries • S Asia divides into two • Applications fail, no connectivity, telnet, VoIP/multimedia, Grid clusters and data transport (e.g. Pakistan) • Decreasing use of satellites, expensive, but still needed for many remote countries in Africa and C. Asia • Last mile problems, and network fragility • Affects data transfer, multi-media, VoIP • Africa ~ 10 years behind and falling further behind, • Internet performance (non subjective, relatively easy/quick to measure) correlate strongly with economic/technical indices • Increase coverage of monitoring to understand Internet performance • Need funding (used to be DoE (research in net mon), SLAC, US State Dept, HEC/MOST Pak), Pak continues, US needs to match
More information/Questions • Acknowledgements: • Harvey Newman and ICFA/SCIC for a raison d’etre, ICTP for contacts and education on Africa, Mike Jensen for Africa information, NIIT/Pakistan, Maxim Grigoriev (FNAL), Connie Logg (SLAC), Warren Matthews (GATech) for ongoing code development for PingER, USAID MoST/Pakistan for development funding, SLAC for support for ongoing management/operations support of PingER • PingER • www-iepm.slac.stanford.edu/pinger, sdu.ictp.it/pinger/africa.html • Case Studies: • https://confluence.slac.stanford.edu/display/IEPM/South+Asia+Case+Study • https://confluence.slac.stanford.edu/display/IEPM/Sub-Sahara+Case+Study • http://sdu.ictp.it/lowbandwidth/program/case-studies/index.html
What is it? • The term "digital divide" was coined in the 1990s to describe the perceived growing gap between those who have access to and the skills to use ICT and those who, for socio-economic and/or geographical reasons, have limited or no access. There was a particular concern that ICT would exacerbate existing inequalities.
Why Does it Matter 4. Sep 05, international fibre to Pakistan fails for 12 days, satellite backup can only handle 25% traffic, call centres given priority. Research & Education sites cut off from Internet for 12 days • School in a secondary town in an East Coast country with networked computer lab spends 2/3rds of its annual budget to pay for the dial-up connection. • Disconnects 2. Telecentre in a country with fairly good connectivity has no connectivity • The telecentre resorts to generating revenue from photocopies, PC training, CD Roms for content. Heloise Emdon, Acacia Southern Africa UNDP Global Meeting for ICT for Development, Ottawa 10-13 July 3. Primary health care giver, somewhere in Africa, with sonar machine, digital camera and arrangement with national academic hospital and/or international health institute to assist in diagnostics. After 10 dial-up attempts, she abandons attempts to connect
Costs compared to West • Sites in many countries have bandwidth< US residence • “10 Meg is Here”, www.lightreading.com/document.asp?doc_id=104415 • Africa: $5460/Mbps/m • W Africa $8K/Mbps/m • N Africa $520/Mbps/m • Often cross-country cost dominates cf. international 1 yr of Internet access > average annual income of most Africans, Survey by Paul Budde Communnications
Overall (Aug 06) • ~ Sorted by Average throughput • Within region performance better (black ellipses) • Europe, N. America, E. Asia generally good • M. East, Oceania, S.E. Asia, L. America acceptable • C. Asia, S. Asia poor, Africa bad (>100 times worse) Monitored Country
UNDP Human Development Index (HDI) • A long and healthy life, as measured by life expectancy at birth • Knowledge, as measured by the adult literacy rate (with two-thirds weight) and the combined primary, secondary and tertiary gross enrolment ratio (with one-third weight) • A decent standard of living, as measured by GDP per capita. Africa PingER - Strong Correlation - Non subjective - Quicker / easier to update
Med. & Africa vs HDI • N. Africa has 10 times poorer performance than Europe • Croatia has 13 times better performance than Albania • Israel has 8 times better performance than rest of M East Med. Countries • E. Africa poor, limited by satellite access • W. Africa big differences, some (Senegal) can afford SAT3 fibre others use satellite • Great diversity between & within regions
Network Readiness Index (NRI) • Ability to participate in and benefit from ICT developments • environment for ICT offered by a country or community • readiness of the community's key stakeholders (individuals, business and governments) • usage of ICT among these stakeholders. • Very similar to TAI (not shown) and DAI. Strong correlations