[brite-users] Plot a topology

Robert P Ricci ricci at cs.utah.edu
Mon Feb 6 11:54:56 EST 2006


At the beginning of the file, you'll need the following two lines:

source tb_compat.tcl
set ns [new Simulator]

The first is Emulab-specific - it loads the parsing code for Emulab. The
second is required for any NS script. It creates a new simulator object,
to which the nodes and links will be attached.

At the end, you'll need these two lines:

create_topology
$ns run

The first is required because BRITE has, instead of directly defining
nodes and links for you, defined a function that, when run, creates the
nodes and links. The second is required for any NS script, and tells NS
to run the simulation.

After doing these things (and the others discovered by you and Michael),
Emulab would parse your NS file. However, there was one more problem -
the NS file that you showed me had lines like this:
        $ns duplex-link $n(9) $n(3) 10.0Mb 0.004703253630954915ms $qtype

Note that the delay is being set to 0.0047 MS! Definitely an unrealistic
delay. So, in order to get Emulab to accept the file, I changed all of
the delays to 0. But, if you're going to run a simulation or emulation
with this topology, you should probably investigate why BRITE is giving
you such small delays.

Thus spake Massimo Canonico on Mon, Feb 06, 2006 at 04:57:37PM +0100:
> I realized to take off just the last comment. Now, I put all comments in
> a new line, and Emulab wants a 'Simulator run' statement. Using the file 
> in attachment, I got this error:

-- 
/-----------------------------------------------------------
| Robert P Ricci <ricci at cs.utah.edu> | <ricci at flux.utah.edu>
| Research Associate, University of Utah Flux Group
| www.flux.utah.edu | www.emulab.net
\-----------------------------------------------------------


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