Re: [ns] buffering and pkt transmission.

[Ya Xu <yaxu@ISI.EDU>]

You can find the answer by reading the chapter 6: links of
ns docs

-ya

On Sat, 27 Oct 2001, abrar hussain wrote:

> Hello ns users,
> 
> I have a basic question related to buffering and pkt transmission.
> 
> Consider a source router R. R is supposed to generate traffic
> havings pkts of size 500 bytes. The interval between pkt
> transmission is 0.004 secs. The outgoing link has a bandwidth of of
> 10 Mbps.
> 
>  	The scenario is something like this ....
> 
> 
> 		Traffic Source	
> 			 ----           10 Mbps
> 			| R  |----------------------------->	
> 			 ----
> 		500 bytes pkt.
> 		0.004 sec pkt interval.
> 		Start flow at 1 sec.
> 
> 	Now if the first bit of the first pkt left router at 1 sec
> then the last bit of the same pkt will leave at 
> 	
> 		1 sec + ( 500 * 8 b / 10Mbps ) = 1 + 0.004 = 1.004 sec.
> 
> So the first pkt is completely transmitted at 1.004 sec.
> 
> Please give pointers to the following questions ...
> 
> (1) At what time-stamp is the pkt queued ? .
> (2) At what time-stamp is it dequed ?  ( is it 1.004 sec ?).
> (3) If the link speed were say 100Kbps ,when will R drop a pkt ?
> 
> 	Do we have a general formula for the last question ?.
> 
> 
> I appreciate your help and thanks in advance.
> 
> Sincerely,
> Abrar.
>