1. 1 Measurements of Internet performance for NIIT, Pakistan Jan – Feb 2004 PingER From Les Cottrell, SLAC For presentation by Prof. Arshad Ali, NIIT

2. 2 Results: Worldwide performance Performance is improving Developed world improving factor of 10 in 4-5 years S.E. Europe, C.Asia 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!!

3. 3 To Pakistan performance Karachi NIIT/Rawalpindi Islamabad Lahore Loss % RTT ms 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 Routes: ESnet (hops 3-8) - DC ATT (9-21) - Karachi

4. 4 From Pakistan Performance Note similarities, probably due to common bottleneck, probably in Pakistan NIIT to SLAC NIIT to CERN Route:Pakistan Telecom (2-5) Rawalpindi, Karachi SingTel (6-10) ESnet (11-14) - PAIX Route: Pakistan Telecom (2-5) Rawalpindi, Karachi Concert (6-9) London DataTAG (11-12).de

5. 5 NIIT performance from U.S. (SLAC) Ping RTT & Loss Nb. Heavy losses during congested day-times Bandwidth measurements using packet pair dispersion & TCP (Jan 2004) abing (pkt-pair dispersion):Average To NIIT: ~350Kbits/s From NIIT: ~365 Kbits/s Iperf/TCP (with SLAC): Average: To NIIT: ~320Kbits/s From NIIT: ~330Kbits/s Iperf/TCP (with CERN): Average: To NIIT: ~270Kbits/s From NIIT: ~300Kbits/s Can also derive throughput (assuming standard TCP) from RTT & loss (monthly) using: BW~1.2*S(1460B)/(RTT*sqrt(loss)  ~ 260Kbits/s (SLAC to NIIT) ~ 630Kbits/s (NIIT to SLAC | CERN) Nominal path bottleneck capacity 364 Kbits/s Preliminary results, started measurements end Dec 2003. Avg daily: loss~1-2%, RTT~320ms

6. 6 Available Bandwidth (Feb ‘04 after upgrade) green line is the bandwidth capacity of current bottleneck –deduced from the minimum packet separation blue line is available bandwidth = capacity-cross-traffic. Use available bandwidth estimator (abing) –Uses packet pair dispersion –Low impact, 40*1450Byte packets –Repeat once/minute –Client at SLAC, mirror/server at NIIT Iperf confirms with: –948Kbps (2streams), –952Kbps (4streams), –1042Kbps (10streams)

7. 7 To NCP Pakistan Cannot use PingER to measure to ncp.edu.pk –Pings blocked at FLAG router (62.216.145.154, AS15412) on way to Comsats (Pakistani ISP) Working with NCP to try and resolve –Trying to contact FLAG Using abing instead –Indicates 2Mbps –But link is 384Kbps Iperf shows 235 - 245 Kbps Rate limiting or shaping? ~ 2MBits/s, but link is 384Kbps Looking for discrepancy

8. 8 Within Pakistan SLAC – Karachi U: –ESnet (hops 3-8) – DC ATT (9-21) – Karachi SLAC – NIIT RawalpindiI: –ESnet (hops 3-6) – SNV, SINGTEL (7-12) – Karachi, Pakistan Telecom Karachi-Rawalpindi SLAC - U Lahore, similar to NIIT SLAC – NSC: –ESnet (hops 1-6), C&W (7-11) Santa Clara – NY, FLAG (12-16) NY – London – Karlsruhe, Comsats NIIT – NSC (Rawalpindi – Islamabad) few miles apart, –No peering in Pakistan, can this be changed? –Route goes via England: PIE (hops 1-5), Concert (6-9)- London, FLAG (10-14) London – Karachi, Comsats (15) –Takes longer than to SLAC

9. 9 Conclusions Big performance differences to sites, depend on ISP (at least 3 ISPs seen for Pakistan A&R sites) To NIIT: –Before upgrade got about 300Kbps - 380Kbps at best –After upgrade get 1 Mbps, as expected –The bottleneck appears to be in Pakistan –There is often congestion (packet loss & extended RTTs) during busy periods each weekday –Video will probably be sensitive to packet loss, so it may depend on the time of day –H.323 (typically needs 384Kbps + 64Kbps), would appear to have been be marginal at best before upgrade, since upgrade has been very successful. No peering Pakistan between NIIT and NSC

10. 10 Bulk Data Transfer Transfer time to send a file of various sizes between 2 sites with given capacity –assume can utilize 50% of capacity –format hours:mins:seconds PingER File size Typical BaBar file sizes 500MB-1GB

11. 11 Interactive Use Voice needs RTT < 250ms or else listener does not know when to speak RTT > 400ms makes productive interactive work such as interactive telnet/X-windows style typing difficult –Screen does not match the keyboard, especially when correcting text Losses: –Losses > 10% TCP connections fail –Losses >4-6% make video conferencing unintelligible for non-native language speakers –Losses of > 3-5% make TCP perform badly –Random loss of 2.5% will make Voice over IP annoying every 30 seconds or so –More realistic burst losses will cause VoIP to be annoying at >1% losses PingER

12. 12 More information NUST Institute of Information Technology (NIIT) –http://www.niit.edu.pk/http://www.niit.edu.pk/ PingER project –http://www-iepm.slac.stanford.edu/pinger/http://www-iepm.slac.stanford.edu/pinger/ ABwE available bandwidth estimator –www-iepm.slac.stanford.edu/bw/abwe/abwe-cf-iperf.htmlwww-iepm.slac.stanford.edu/bw/abwe/abwe-cf-iperf.html