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I first tried with the default windows XP TCP option(It doesn't have TCPWindowSize option and TCP1323 in its Registry setting). I dynamically set those options using TCP optimizer. Here I list out the result with and without TCP Tweaking option.

I see no major improvements in TCP after increasing window size optimally too.

What value should I set to increase the performance?


Without any window size and MTU setting from server to client (receiving)

TCPWindowSize :



Size:586 MB

total duration : 03:47

With window size extension from server to client (receiving)

Bandwidth :100 Mbps

Latency: 100ms

BDP :1250000

TCPWindowSize : 1250000

MTU :1500



total duration : 03:44

With window size extension from server to client (receiving)

TCPWindowSize :64240

MTU :1500

TTL :112

Size: 586MB

total duration : 03:49

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migrated from Apr 13 '10 at 2:42

This question came from our site for professional and enthusiast programmers.

See this question, it explains why you probably shouldn't try to optimize the TCP stack. Your bottleneck is probably somewhere else (slow hard disks perhaps?)

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The link in this answer refers to a page that has been removed. – martineau Aug 15 '12 at 22:46

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