[c-nsp] STM-1 - TCP throughput

[Mikael Abrahamsson]

On Fri, 1 Dec 2006, Zahid Hassan wrote:

> Dear All,
>
>
> Can anyone shed any light into the relationship between RTT and TCP
> throughput.
>
> I have a STM-1 circuit where the Telco RTT SLA is ~ 30ms and I am getting
> a maximum TCP throughput of 20 M/s.
> When I do a test using UDP I am getting over 80 M/s.
>
> Is there anything that can done to fine tune the TCP stack to improve the
> achievable throughput ?

You don't say what OS but http://www.speedguide.net/ has a lot of 
information regarding this for several OSes.

There is also a lot of information to be had by googling for things like 
"tcp window size" and alike.

http://en.wikipedia.org/wiki/Transmission_Control_Protocol#TCP_window_size 
might be a good starter if you don't know what tcp window size is.

-- 
Mikael Abrahamsson    email: swmike at swm.pp.se