[ns] calculation error of pkt delays

[Bo Wen <bowen@mail.wsu.edu>]

Hi, all,

When I calculate packet delays by using arrival time
to substract time stamp of header, there is alway
an error between my result and what it should be,
that is, propagation delay plus transmission delay 
(also appears in trace file).  I removed queue on 
links, since I simulated circuiting switching, 
so, there was no queuing delay.

So, if I want to get accurate pkt delays, where should
I count the arrival time?  (I did once it at the agent
receiver, but results have errors as above).

Thanks a lot!
Bo Wen