Bandwidth issues in the Sprint network

Sam Stickland sam_mailinglists at
Tue Apr 8 16:51:14 UTC 2008

Could be your TCP window size? A 17520 byte TCP window (Windows 2000) 
will cause a single flow to top out at 5Mbps at about 50ms. What is the 
latency on the link?

Try some figures here and see what limit you might be hitting:


Brian Raaen wrote:
> I am currently having problems get upload bandwidth on a Sprint circuit. I am 
> using a full OC3 circuit.  I am doing fine on downloading data, but uploading 
> data I can only get about 5Mbps with ftp or a speedtest.  I have tested 
> against multiple networks and this has stayed the same.  Monitoring Cacti 
> graphs and the router I do get about 30Mbps total traffic outbound, but 
> individual (flows/ip?) test always seem limited.  I would like to know if 
> anyone else sees anything similar, or where I can get help.  The assistance I 
> have gotten from Sprint up to this point is that they find no problems.  Due 
> to the consistency of 5Mbps I am suspecting rate limiting, but wanted to know 
> if I was overlooking something else.

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