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Re: [ns] TCP Session start and stops





>Again this is all explained in the ns manual section 33.2.4 (as well as
the
>recv and resume callbacks) I suggest you just play around with it and
if you
>run into difficulties send the tcl script and describe what problem you
>encountered.
>

Thanks Mark.

I have used "done" before to emulate sequential request/response -
similar to the NETPERF and other real life tools. I think Biplab
was looking for something similar to emulate new TCP flows
with each transfer. I don't think using "send" the way you
describe it will do the reset of TCP state.

I have used "reset" in the past and found that it doesn't do 
a comprehensive resetting of the entire TCP state. As such
certain parameters would report incorrect results. Another
way of solving this was to allocate and start new FTP 
agents from within "done". However, in this case, 
I found that I ran out of memory when the number of flows
was large or the simulation duration was long. 
I never solved the latter problem but simply ensured that 
I limited the simulations to the size of memory.

If anyone has sample code that frees TCP agents
from within done, (without causing a segmentation dump),
I would be grateful to get a copy - I guess you have to 
free not the current agent but previous ones that have 
already completed.

Best,
Nabil