Re: link dynamics bug

[Kannan Varadhan <kannan@ISI.EDU>]

Hi Hyogon,

> Yes, I was missing something. I was bringing down *all* links in the
> script, and after I changed the setting the simulator worked just as
> I expected. Please ignore my stupid question above.

There are two things going on.  You identified one, i.e. you are causing
a node to fail, instead of a particular link.  This is as documented in
http://www-mash.cs.berkeley.edu/ns/nsDoc.ps.gz.

However, there is one more problem.  You should have expected some
throughput when the node was up.  Because we fucked up the design of
network interfaces earlier, the dynamics code tries a simple and
generic way of composing this link which does not work in some
special cases.  Hence, you do not see any throughput at all.  If you
use the following:

	set bogusTraceFile [open /dev/null w]
	$ns trace-all $bogusTraceFile

at the top of your script, you might be more pleased.  Note however,
this should be a short-time hack.  Fixing that interfaces code is
high on my list of things to do, but defending and finding a job are
a tad bit higher.  Nevertheless, it will be fixed before summer's end.


Kannan

--
kannan@isi.edu
http://www.isi.edu/~kannan