1. Masaki Hirabaru CRL, Japan APAN Engineering Team Meeting APAN 2003 in Busan, Korea August 27, 2003 Common Performance Measurement Platform

2. Real Situations MIT Haystack – CRL Kashima e-VLBI Experiment on June 27, 2003 to measure UT1-UTC in 24 hours –41.54 GB CRL  MIT 107 Mbps (~50 mins) 41.54 GB MIT  CRL 44.6 Mbps (~120 mins) –RTT ~220 ms, UDP throughput 300-400 Mbps However TCP ~6-8 Mbps (per session, tuned) –BBFTP with 5 x 10 TCP sessions to gain performance HUT – CRL Kashima Gigabit VLBI Experiment -RTT ~325 ms, UDP throughput ~70 Mbps However TCP ~2 Mbps (as is), ~10 Mbps (tuned) -Netants (5 TCP sessions with ftp stream restart extension) They need high-speed / real-time / reliable / long-haul high performance data transfer.

3. Purpose Ensure ~1 Gbps end-to-end performance in high bandwidth-delay product networks –to support for networked science applications –to help operations in finding a bottleneck –to evaluate advanced transport protocols (e.g. Tsunami, SABUL, TFRC, HSTCP, FAST, XCP, ikob)

4. Kwangju Busan 2.5G Fukuoka Korea 2.5G x1 KOREN Taegu Daejon 2.5G + 40G 0.6G1Gx2 QGPOP Seoul XP Genkai XP Kitakyushu Tokyo XP CRL Kashima 0.1G Fukuoka Japan 250km 1,000km 2.5G + 1G x2 TransPAC 10,000km 4,000km Los Angeles Chicago New York MIT Haystack HUT 10G 1G APII/JGN Abilene 0.1G? Helsinki 2.4G Stockholm 0.6G 2.4G GEANT Nordunet funet CRL Koganei 1G 7,000km Network Configuration (incl. near future plan)

5. Proposal Place a “good” PC box for performance measurement at each NOC / POP as well as experiment sites (hop-by-hop and end-to- end) Advanced rate-based / window-based transports (kernel may be modified) Common measurement method / tool (iperf?) Monitor for TCP / UDP protocol behavior (tcpdump & tcptrace, packet loss detector) Combine with ping, traceroute, routing stats Share the boxes and develop scheduler to avoid duplicate tests Need a consensus to put a strong pressure on our networks (?)

6. Examples Data Unavailable From Tokyo XP to KOREN Busan Blue line: UDP (loss < 1%)  better way Green area: TCP (with proper window size) Traffic Between Genkai XP and KOREN Busan Test stopped

7. Questions? See http://www2.crl.go.jp/ka/radioastro/index.html for VLBI