[ns] Simultaneous start

["Antonello" <digioia.m@tin.it>]

Hi,
I'm trying to evaluate performance of queueing algorithm. Actually I'm
simulating a simple topology:
2 flows CBR --> flow 1 send 8192 bytes every 33.33 ms  ($cbr1)
                             flow 2 send 8192 bytes every 8 ms    ($cbr0)

In Tcl code I wrote: $ns at 0 "$cbr1 start"
                                  $ns at 0 "$cbr0 start"
If I swap these two lines of code results are quite different....why?
I need to show that service curve algorithm performs better for flows that
need fixed delay bound ; if I use code with cbr1 first the results are
identical (with a simple DropTail); if I use code with cbr0 first service
curve algorithm appears better. What is wrong in this approach?

Thanks,
@nto