WAN transfer rates

Iljitsch van Beijnum iljitsch at muada.com
Tue May 11 09:19:07 UTC 2004

On 11-mei-04, at 10:24, Jeff Nelson wrote:

> I realize that transfer rates across the Internet diminish 
> significantly
> with latency, but what's the good answer for someone shrunk down to
> <10Mbps when the smallest pipe between them is 100Mbps and latency is
> <40ms?

> Does anyone have reference to any study done in this area? I'm sure
> window tuning can alter this, but I'm interested in average statistics.

The best you can do is transfer a window size per round trip. You can 
see the window size with tcpdump or one of its cousins, and looking at 
netstat output will get you somewhere in the neighborhood too. So if 
your window is 16k and your RTT 25 ms, that's 16k every 25 ms. Or 16 * 
1000 / 25 = 640k per second = 640000 * 8 = 5 Mbps.

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