[c-nsp] how to test multicast?

[Caren Litvanyi]

On Mon, 11 Jul 2005, Jared Mauch wrote:

> On Mon, Jul 11, 2005 at 05:04:28PM -0500, Andy Webster wrote:
> > hi,
> >  	I am trying to create a list of good resources to use to test
> > multicast.  I think what I really would like to compile is a list rps
> > that other people use to mtrace to in order to prove multicast is
> > working?  Does anyone else have pointers to something like this?   
> 
> 	you may want to look at using iperf.

Second that.  We often use iperf as the sender, and rtpqual as the
receiver for simple testing.
http://dast.nlanr.net/projects/iperf/
ftp://ftp.ee.lbl.gov/rtpqual.c

something like:
iperf -u -c <group> -p <port> -b <bps> -i 5 -T <ttl> -t <duration>
and
rtpqual <group> <port>

It's something simple that seems to work for us, anyway.
Of course you have to have access to boxes on either end,
or someone willing to help you by running such programs.
Since I think you are in govt/education, usually you can find
someone willing.

Mtracing to RPs doesn't really prove whether multicast is working
or not, but it can help find certain types of problems.  There are
a bunch of problems it can't catch afaik.

>  [...] 
> 	you can also use the multicast beacon
> 
> http://dast.nlanr.net/projects/beacon/
> 

We make use of the beacon as well.  It's been used among a "community"
of interested senders and receivers where they all subscribe to one
beacon group and report to a certral server, or a beacon group is
run among monitoring machines at a set of PoPs to show inter-PoP
multicast is functioning.  You can also join the general beacon group
and only run the client, as seen at http://beacon.dast.nlanr.net/,
which has several participants you are likely familiar with from the
education community.

Caren
------------
Caren Litvanyi, network engineer
Global Research NOC at Indiana University
litvanyi at grnoc.iu.edu