Re: TCP RTT woes revisited


mills@huey.udel.edu
Mon, 15 Dec 86 18:07:57 EST


Craig and Bob,

Keeping roundtrip-delay samples on a per-packet basis really does help
(the fuzzballs have been doing that for several years), as does initializing
the estimator with the SYN/ACK exchange. Another thing, first pointed out
by Jack Haverty of BBN, is the behavior when the window first opens
after it has previously closed. If the ACK carrying the window update is
lost, performance can lose big. This may be one reason TP-4 uses a different
"active ACK" policy. While at it, consider the receiver policy and when
to generate ACKs (delayed or not). Silly implementations that always send



This archive was generated by hypermail 2.0b3 on Thu Mar 09 2000 - 14:37:00 GMT