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What is theTCP Window size setting for?

PostPosted: Tue Mar 12, 2002 1:30 pm
by dexter
To optimize use of high latency connections, NewsBin provides a setting on the "Network" tab of the "Settings" screen. A high latency connection is a connection where the download datarate is much higher than the upload datarate. The setting we provide is the "TCP Window Size". This setting configures the network connection to send more data down on the fast link for each packet acknowledgment on the slow uplink. For example, say you have a 100MB download and your TCP window size is 16K. You will be acknowledging 6250 packets with your slow uplink connection. If you crank your TCP window size up to 50K, you will only be sending 2000 acknowledgments. The tradeoff is that there is more room for bit errors in 50K than in 16K. On a clean link asymmetric link ADSL, one-way cable, and possibly Satellite on a clear day, you can take advantage of large TCP window sizes. On dialup, marginal cable modems, wireless modems, or satellite on a rainy day, you may want to keep your TCP window size smaller. Of course experimentation is the only way to truly optimize this setting.