[ns] Re: Diffserv Model for NS 2.1b5 available from Nortel Networks OpenIP Environment Group

[Lloyd Wood <l.wood@eim.surrey.ac.uk>]

On Sat, 29 Jul 2000, Lloyd Wood wrote:
> On Fri, 28 Jul 2000, Peter Pieda wrote:
> 
> > A new release of the Nortel Networks Open IP Diffserv Model for NS 
> > is available for download at http://www7.nortel.com:8080/CTL/.
> > 
> > The following additions have been made to the model:
> > 	1. Class Selector PHB and Default PHB added.
> > 	2. Bounded Strict Priority Scheduler
> > 	3. DropTail AQM
> > 	4. Minor code adjustments (see feedback)
> > 
> > Thanks to all of those who gave feedback.
> > 
> > There is some on-going work to port this to the latest release of NS.
> 
> Porting it to the latest release is easy; patches (below)

are available at:
http://www.isi.edu/nsnam/archive/ns-users/webarch/2000/msg03653.html

> are pretty much what I posted last time bar the line nos.
> 
> However, although old policer regression tests pass just as before,
> the new 'schedular' regression tests fail on current ns due to slight
> differences in packet counts.

We've looked into this a bit further, testing release 6 of the Nortel
code with a very recent ns snapshot, with a 2.1b6-4-Nov-99 snapshot,
and with ns-2.1b5a on Solaris. These all gave us the same results for
the scheduler regression tests, which differ from the regression test
results supplied with the Nortel code.

So we built ns 2.1b5a under Redhat Linux, and got the same results -
which again didn't match Nortel's supplied scheduler regression
results. No problems with the policer regression tests, though.

You can grab a copy of our scheduler regression test results from:
http://www.ee.surrey.ac.uk/Personal/L.Wood/ns/nortel-6-schedular-output.txt

cheers,

L.

<L.Wood@surrey.ac.uk>PGP<http://www.ee.surrey.ac.uk/Personal/L.Wood/>