Re: [ns] Question about FullTCP

[Dimitris Velenis <dbelen@netmode.ece.ntua.gr>]

Hi Sandro, 

The record proc performs periodic sampling of the variables you specify in it,
and therefore there is no guarantee that it will record ALL values. 
You'd better use the tracing facilities provided by the agent.
You can do something like this:

$tcp_agent attach-trace $trace_file_handle
$tcp_agent trace t_seqno_
$tcp_agent trace ack_


You can also get sequence number & ack info from the packet trace file, 
using grep & awk.

Dimitris.

On Wed, Nov 21, 2001 at 09:44:00AM +0100, Sandro Petrizzelli wrote:
> Hi to all,
> I'm using FullTCP for my simulations. I want to use the procedure called
> "record" (from the tutorial of Marc Greis) to record values of "seqno"
> produced by the sender and "ackno" produced by the receiver, but I have
> found only the variable called "t_seqno_" to record sequence numbers, while
> there is no variable for ACK numbers. Can anyone help me?
> 
> Thanks in advance
> 
> Sandro Petrizzelli
> 
> 
> P.S. Here is my procedure "record":
> 
> proc record {} {
>  global ns mitt ricv output
>  set ns [Simulator instance]
>  set time 0.1
>  set now [$ns now]
>  set numseq [$mitt set t_seqno_]
>  puts $output "$now $numseq "
> 
>  $ns at [expr $now+$time] "record"
> }
> 
> 
> 
> 

-- 
Dimitris Velenis                              <dbelen@netmode.ece.ntua.gr>
Network Management & Optimal Design Lab
National Technical University of Athens