[c-nsp] TCP throughput /WAN delay simulation with back to back routers

[Brandon Applegate]

On Wed, 19 Aug 2009, Thilak T wrote:

> Hello Folks ,
>
> I am trying to test TCP throughput with different variables. I want to
> simulate a delay of aprox 45msec between two test PCs connected two
> bat to back routers . How do we introduce an artificial delay where in
> the actual delay is on 2-3 msec.Using cisco routers.?

Google 'dummynet'.  FreeBSD with Dummynet does this nicely.  If you really 
want it transparent, you can build a dummynet machine with 2 NICs and do 
it in bridged mode.  You can play with bandwidth, delay, introduce packet 
drops etc.

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Brandon Applegate - CCIE 10273
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