TCP and WAN issue

Roland Dobbins rdobbins at
Tue Mar 27 20:37:03 UTC 2007

On Mar 27, 2007, at 1:26 PM, Philip Lavine wrote:

> inherent in Windows (registry tweaks seem to not functions too well)?

You should certainly look at your MTU and MSS values to ensure there  
are no difficulties of that sort.  Is there any other factor such as  
perhaps slow DNS server (or other lookup-type services) responses  
which can be contributing to the perceived slowness?  How about  
tuning the I/O buffers on the relevant routers?  Can you tune the I/O  
buffers on the servers?

And what about your link utilization?  Is the DS3 sufficient?  Take a  
look at pps and bps, and take a look at your average packet sizes  
(NetFlow can help with this).  Are your apps sending lots of smaller  
packets, or are you getting nice, large packet-sizes?

Finally, if none of the above help, you could look at something like  
SCTP, if your servers and apps support it.  But I'd go through the  
above exercise, first.

Roland Dobbins <rdobbins at> // 408.527.6376 voice

         Words that come from a machine have no soul.

                       -- Duong Van Ngo

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