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Re: What is txtime()?



txtime(p) is the time necessary to trasmit the full packet on a link
with zero delay, viz. end_trasmission_time - start_trasmission_time,
viz. packet_size(bit)/link_rate(bit/sec) (look in delay.h).
The arrival time at node i+1 is defined as that time at which the last
bit of packet k has arrived at this node, so the LinkDelay at node i
schedules the arrival of k at node i+1 at time txtime. If there is also
a delay it will be txtime + delay, so
		s.schedule(target_, p, txt + delay_);

Gang Zhang wrote:
> 
> Hi, there:
> 
> PLease take a look at the following question:
> 
> it is in the file delay.cc
> 
> +++++++++++++++++++++++++++++++++++++++++++++++++
> void LinkDelay::recv(Packet* p, Handler* h)
> {
>         double txt=txtime(p);
> 
> /************ what do the txtime(p) mean      *****/
> 
>         Scheduler& s=Scheduler::instance();
>         if (dynamic_) {
>                 Event* e=(Event* )p;
>                 e->time_=txt+delay_;
>                 itq_->enque(p); //for convinience, use a queue to store
> packets in
>                 s.schedule(this, p, txt+delay_);
>         } else {
>                 s.schedule(target_, p, txt + delay_);
>         }
>         s.schedule(h, &intr_, txt);
> }
> 
> ++++++++++++++++++++++++++++++++++++++++++++
> could sb give me a hint? thanks a lot.
> 
> gang

-- 
Massimo Pegorer, student
Dipartimento di Elettronica e Informatica
Universita' degli Studi di Padova
Padova - ITALIA