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to TCP or not to TCP. D. Towsley U. Massachusetts. throughput. loss prob. Observations on TCP. TCP 1/p ½ (defined as a response function) not appropriate for region of low p redefine response function for small p ~ 1/p 0.84 p < 0.001 (S. Floyd)
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to TCP or not to TCP D. Towsley U. Massachusetts
throughput loss prob. Observations on TCP • TCP 1/p½(defined as a response function) • not appropriate for region of low p redefine response function for small p ~ 1/p 0.84 p < 0.001 (S. Floyd) or ~ 1/p , p < 0.001 (T. Kelly) • both do well! • at least 1Gbps • fairness? Enhanced TCP CC algorithm robust
the hard stuff! Observations on Transport • several successful transport protocols • even TCP (carefully tuned)! • > 1 GBs • current limitations lie outside transport protocol • access BW (1GE) • NIC issues • I/O (disk to NIC) • OS issues
HSTCP? throughput loss prob. Observations on Transport (ctd.) • need for standardized protocol • reduces net admin costs frees up money for research • specialized vs. general purpose • scalable protocols • 10Gbs – 40 GBs – 160Gbs – 640Gbs • bit errors? • congestion notification? • startup, fairness 1/p