TCP Use and Performance on Internet 2

SampledNetFlow data fr om a core Inter net2 router areanalyzedto characterizethe curr ent useand performance of Inter net2, with particular emphasison bulk TCP transfers. The distrib ution of thr oughput, transfer size, duration, and averagepacket sizefor 48,301observed bulk TCPs is presented. The top 10% of bulk transfer TCPs achieved thr oughputs of 3.9Mbps or greater, while the top 1% of bulk transfer TCPsachieved thr oughputsof 23Mbps or greater. The median bulk transfer TCP thr oughput observedwas880Kbps. Summariesof application and IP protocol mixes are presented. Popular applications included: NNTP (19.3% packets, 22.8% octets), active FTP (11.9% packets,14.2% octets),HTTP (10.5% packets,9.5% octets), and multicast (6.6% packets, 6.2% octets). Most used IP protocols were TCP (85.6% packets, 88.7% octets), UDP (12.5% packets, 10.0% octets), and ICMP (1.4% packets, 0.8% octets). Keywords— Inter net2, Abilene, OC-48c, backbone,TCP, thr oughput, NetFlow.