1. Support for high performance UDP/TCP applications Xing Li 2007-08-25

2. Background More and more demonstration and trials on high- performance applications –Application-specific stream or data –Consume large network bandwidth –Heavily rely on network support What can NOC do to support for it? –If there is a lambda path lucky! RTT is still an issue –Otherwise Measurement and monitoring –Network performance measurement tool –Application-specific measurement tools End to end performance guarantee –Inter-AS routing adjustment –Agreement on enabling application-related ACLs

3. Where are the bottlenecks? AS2 AS3 AS1 access Bad cabling Wrong speed Wrong duplex mode Bad cabling Wrong speed Wrong duplex mode firewall Bandwidth bottleneck Host parameter s Host parameter s

4. Possible Paths

5. Case study In KR It is not via the CERNET – KR path It is not via the CERNET– APAN – KR path It is not via the CERNET – TEIN2 – KR path It is not via the CERNET – TEIN2 – JP – KR path It is via the CERNET – APAN – Abilene – KR path And the return path may be totally different

6. The Ideas Use measurement tools to –Help users to do self-service –Separate the network problems from the end system problems –Find the network segments which cause the problem

7. SASM Framework

8. The operation modes of basic tools

9. Server discovery and registration

10. From Arlington to TEIN2 Beijing server using WALN Not good using RJ45 Good

11. TCP transfer speed Formula SUN §WINDOWS Theory

12. The TCP measurement Tool

13. The testing steps Default test –The default TCP transfer speed for the e2e peer Window size test –Check the client window Parallel session test –Check the server window –Physical speed limit Comparison with ping and UDP (dvping) tests –Check packet loss (ping and dvping) –Check RTT (ping and dvping) –Check throughput (dvping)

14. Comparison with UDP (dvping) Compare with UDP (dvping) –Check RTT, packet loss and the physical speed limit

16. Summary of the TEIN2 NOC measurement servers serverclinet ICMP U/UDP M/UDP U/UDP U/TCP U/UDP ping ssmping dvping iperf –c smjoin iperf –s smclock dvmcast ssmpingd Socket stack U – Unicast M - Multicast

17. 202.179.252.102 202.179.244.105 202.179.242.102 202.112.35.200 CERNET TEIN2 TEIN2 Measurement Server Locations

18. SASM Framework

19. A Document http://noc.tein2.net:8036/support-for-hp/hp-mc-20070507.html Login: tein2passwd: tein2

20. eVLBI example

21. Summary Application specific tools –dvping (UDP) –iperf (TCP/UDP) Distributed servers alone the path –Scalable Application Specific Measurement (SASM) Open traffic monitoring –SNMP –Netflow Applications –TCP vs. UDP International collaboration