PingER

SLAC IEPM PingER and BW monitoring & tools

Presented by Les Cottrell, SLAC

At LBNL, Jan 21, 2003 www.slac.stanford.edu/grp/scs/net/talk03/lbl-jan04.ppt

1

History of the PingER Project

• Early 1990’s: SLAC begins pinging nodes around the world to evaluate the quality of Internet connectivity between SLAC and other HEP Institutions.

• Around 1996: The PingER project was funded making it the first Internet end-to-end monitoring tool available to the HEP community.

• Today: Believed to be the most extensive Internet end-to-end performance monitoring tool in the world 2 PingER

PingER Today

• Today, the PingER Project includes 35 Monitoring hosts in 12 countries. They are monitoring Remote hosts in 80 countries. Over 55 remote sites.

• THESE COUNTRIES COVER 75% OF THE WORLD POPULATION AND 99% OF THE INTERNET CONNECTED POPULATION!!!

Just added Pakistan!

Colored by region Colored countries have remote PingER hosts 3 PingER

PingER Architecture

PingER • • • There are three types of hosts

Remote-hosts

:

Archive Archive

hosts being monitored

Monitoring-hosts

:

Monitoring REMOTE Monitoring

Make ping measurements to remote hosts

REMOTE Archive/Analysis hosts

: gather data from Monitoring-sites, analyze & make reports

REMOTE REMOTE Monitoring REMOTE REMOTE REMOTE Monitoring REMOTE

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Methodology

• Every 30 mins send 11*100Byte followed by 10*1000Byte pings from monitor to remote host • Low impact: – By default < 100bits/s per monitor-remote host pair – Can reduce to ~ 10bits/s – No need for co-scheduling of monitors • Uses ubiquitous ping – No software to install at any of over 500 remote hosts – Very important for hosts in developing countries • By centrally gathering the data, archiving, analyzing and reporting, the requirements for monitoring hosts are minimal (typically 1-2 days to install etc.) 5

Worldwide performance

• • Performance is improving • Developed world improving factor of 10 in 4-5 years • S.E. Europe, Russia , catching up • India & Africa worse off & falling behind • Developing world 3-10 years behind

Many institutes in developing world have less performance than a household in N. America or Europe

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Current State – Aug ‘03 (throughput Mbps)

Monitoring Country

• Within region performance better – E.g. Ca|EDU|GOV-NA, Hu-SE Eu, Eu-Eu, Jp-E Asia, Au-Au, Ru Ru|Baltics • Africa, Caucasus, Central & S. Asia all bad Bad < 200kbits/s < DSL Poor > 200 < 500kbits/s Good > 1000kbits/s

Network Readiness Index vs Throughput

• NRI from Center for International Development, Harvard U. http://www.cid.harvard.edu/cr/pdf/gitrr2002_ch02.pdf

NRI Top 14 Finland US Singapore Sweden Iceland Canada UK Denmark 5.92

5.79

5.74

5.58

5.51

5.44

5.35

5.33

Taiwan Germany Netherlands 5.28

Israel 5.22

Switzerland 5.18

Korea 5.31

5.29

5.10

• NRI correlates reasonably well with Network Readiness 8



Typical uses • Troubleshooting

 Discerning if a reported problem is network related   Identify the time a problem started Provide quantitative analysis for Network specialists  Identifying step functions, periodic network behavior, and recognize problems affecting multiple sites.



Setting expectations (e.g. SLAs)



Identifying need to upgrade

Providing quantitative information to Policy makers & Funding agencies

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Seeing the effects of upgrades

Karachi

Pakistan performance

Routes: ESnet (hops 3-8) - DC ATT (9-21) - Karachi NIIT/Rawalpindi Islamabad Loss % RTT ms Lahore Routes: ESnet (hops 3-6) - SNV SINGTEL (7-12) - Karachi Pakistan Telecom Karachi Rawalpindi Routes: ESnet (hops 3-6) - SNV SINGTEL (7-12) - Karachi Pakistan Telecom Karachi Lahore 10

NIIT performance from U.S. (SLAC)

Preliminary results, started measurements end Dec 2003.

Ping RTT & Loss Nb. Heavy losses during congested day-times Avg daily: loss~1-2%, RTT~320ms

Bandwidth measurements using packet pair dispersion & TCP

ABW (pkt-pair dispersion):Average To NIIT: ~350Kbits/s From NIIT: 365 Kbits/s Iperf/TCP: Average: To NIIT: ~320Kbits/s From: NIIT 40Kbits/s Can also derive throughput (assuming standard TCP) from RTT & loss using:

BW~1.2*S(1460B)/(RTT*sqrt(loss)

 ~ 260Kbits/s Nominal path bottleneck capacity 1Mbits/s 11

In Summary PingER provides ongoing support for monitoring and maintaining the quality of Internet connectivity for the world wide scientific community. Information is available publicly on the web http://

www-iepm.slac.stanford.edu/cgi-wrap/pingtable.pl

PingER also quantifies the extent of the “Digital Divide” and provides information to policy makers and funding agencies.

12 PingER

IEPM-BW

• Need something for high-performance links – 10pings/30 mins, i.e. min=0.21% in day, or 0.007% in month (10 -8 BER) – today’s better links exceed this – Ping losses may not be like TCP losses • Need for Grid, HENP applications and high performance network connections – Set expectations, planning – Trouble-shooting, improving performance – Application steering – Testing new transports (e.g. FAST, HS-TCP, RBUDP, UDT), applications, monitoring tools (e.g. QIperf, packet-pair techniques …) in production environments – Compare with passive measurements, advertised capacities 13

Methodology

• Monitoring host every 90 minutes (+- randomization) cycles through collaborating hosts at several remote sites: – Sends active probes in-turn for: bbftp, gridtcp, bbcp, iperf1, iperf, (qiperf), ping, abwe … • Also measures traceroutes at 15min intervals • Uses ssh for code deployment, management and to start & stop servers remotely – Deploy server code for iperf, ABwE, bbftp, GridFTP & various utilities • 10 monitoring sites, each with between 2 and 40 remote hosts monitored – Main users SLAC (BaBar) & FNAL (D0, CDF, CMS) • Data archived, analyzed, displayed at monitoring hosts 14

Deployment

Monitor

HENP Net research

100Mbits/s host

Gbits/s host 15 125 measured bw Aug ‘02

• Time series: – Overplot multiple metrics – + route changes – Zoom, history – Choose individual metrics

Visualization

Scatter plots Histograms Access to data 16

Traceroutes

• Analyse for unique routes, assign route #s • Display route # at start, then “.” if no change • If significant change, the display route # in red • Links to: – History – Reverse – Single host – Raw data – Summary for emailing – Available BW – Topology Several routes changes simultaneously 17 Demo

Topology

• Select times & hosts & direction on table • Mouse_over to see router name • Click on router to see sub path below • Colored by deduced AS • Click on end nodes to see names of all hops 18

Performance (ABwE)

• Requires ABwE server (mirror) at remote sites • Gets performance for both directions • Low impact 40 * 1000 byte packets • Less than a second for result • Can do “real-time” performance monitoring

Current bottleneck capacity

(Usually limited by 100FE) Iperf (90m)

Available bandwidth Cross-traffic

24 hours 19

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ABwE/Iperf match: Hadrian to UFL Heavy load ( xtraffic ) appeared It shows new DBC on the path

Normal situation

CALREN shows sending traffic 600 Mbits/s IPLS shows traffic 800-900 Mbits/s

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Abing CLI • Demo abing command line tool

– Since low impact (40*1000 packets) can run like ping 22

• MonALISA

Navigation

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Prediction, trouble

• For ABwE: in bandwidth qualifying effectiveness – Looking at NLANR change detector) • – Look at correlation between RTT /Abstracts/talk_03.html

after if changed), bandwidth info (fwd & rev) – Fold in diurnal changes with filtering

NDT

info,

shooting

• Working on auto detection of long term (many minutes) step changes – Developed simple algorithm and (McGregor/H-W Braun plateau http://www.ripe.net/pam2001 performance & route changes & – For significant changes, gather: RTT, routes (fwd/rev, before & – Generate real-time email alerts demo Predictions Diurnal 24

Program API

• Not realistic to look at thousands of graphs • Programs also want to look at data. E.g.

– Data placement for replica servers – Analysis, visualization (e.g. MonALISA) – Trouble shooting • Correlate data from many sources when suspect/spot problem • Publish the data in standard way • W3C Web Service, GGF OGSI Grid Service – Currently XMLRPC and SOAP servers – Using Network Measurement Working Group schema ( NM-WG .xsd

) • Demo mainly proof of principal, to access IEPM single & multistream iperf, multistream GridFTP & bbftp, ABwE and PingER data – Not pushing deployment and use until schema more solid 25

IEPM SOAP Client

#!/usr/local/bin/perl -w use SOAP::Lite; my $node = "node1.cacr.caltech.edu"; my $timePeriod="20031201-20031205T143000"; my $measurement = SOAP::Lite ->service('http://www-iepm.slac.stanford.edu/tools/soap/wsdl/IEPM_profile.wsdl') ->GetBandwidthAchievableTCP("$node", "$timePeriod"); print “Host=“ .$measurement->{'subject'}->{'destination'}->{'name'},"\n"; print $measurement->{'subject'}->{'destination'}->{'address'}->{'IP'},"\n"; print “Times:\n”.$measurement->{'path.bandwidth.achievable.TCP'} ->{'timestamp'}->{'startTime'},"\n"; print “Values:\n”.$measurement->{'path.bandwidth.achievable.TCP'} ->{'achievableThroughputResult'}->{'value'},"\n"; Host=node1.cacr.caltech.edu

Not-disclosed Times: 8 1070646905 1070652306 1070657705 Values: 1.55 176.43

Results

1070528106 1070533504 1070538907 1070544307 1070549706 1070555108 1070560505 107 0565907 1070571306 1070576706 1070582106 1070587506 1070592906 1070598310 107060 3706 1070609111 1070614506 1070619905 1070625306 1070630706 1070636106 107064150 183.5 174.3 196.76 188.75 196.67 196.05 195.86 187.69 192.91 152.99 181.85 193.0

3 190.21 190.54 168.71 166.79 196.17 172.1 183.77 194.44 195.84 194.01 192.49 17 For more see: http://www-iepm.slac.stanford.edu/tools/web_services/ 26 Demo: http://www-iepm.slac.stanford.edu/tools/soap/IEPM_client.html

For More Information

• PingER: • – – www-iepm.slac.stanford.edu/pinger / • ICFA/SCIC Network Monitoring report, Jan04 www.slac.stanford.edu/xorg/icfa/icfa-net-paper-jan04.html

The PingER Project: Active Internet Performance Monitoring for the HENP Community , IEEE Communications Magazine on Network Traffic Measurements and Experiments .

• IEPM-BW – http://www-iepm.slac.stanford.edu/bw/ • ABWE: www-iepm.slac.stanford.edu/bw/abwe/abwe-cf-iperf.html

http:// moat.nlanr.net/PAM2003/PAM2003papers/3781.pdf

and 27 PingER