Fwd: ssmping

[Thomas D. Uram]

Very cool, even if it is only for SSM.  We could build a similar tool for ASM.

Also interesting is the mention of dbeacon at the bottom of the ssmping page:

http://artemis.av.it.pt/~hsantos/dbeacon/

Tom


On 04/22/05 09:55, Robert Olson wrote:
> some cool tech.
> 
> Begin forwarded message:
> 
>     *From: *Stig Venaas <Stig.Venaas at uninett.no>
>     *Date: *April 22, 2005 9:11:32 AM CDT
>     *To: *wg-multicast at internet2.edu
>     *Subject: ssmping
>     *
>     Hi
> 
>     I've written a utility called ssmping. This is based on the ssmping
>     idea by Pavan Namburi, Kamil Sarac and Kevin C. Almeroth. They way
>     I've done this is slightly different however, I only use UDP and
>     need no support from the network.
> 
>     The idea is pretty simple. On a host one runs a daemon called ssmpingd.
>     Let's say the host has unicast address S.
> 
>     On a client you run a utility called ssmping which is sort of like
>     normal ping. It joins (S,G) (with S the unicast address of the server
>     and the group G is hardcoded), and then sends unicast UDP packets to S
>     every second.
> 
>     When the daemon receives a unicast request, it will send a unicast
>     packet, and also a multicast packet to G.
> 
>     The client should receive both the messages. If it receives the unicast
>     but not the multicast, you know multicast doesn't work.
> 
>     The tool supports both IPv4 and IPv6. Let me give you an example.
> 
>     At ssmping.uninett.no I'm running ssmpingd. It has both IPv4 and IPv6
>     multicast connectivity.
> 
>     At xiang.ecs.soton.ac.uk I run the client and get:
> 
>     sv at xiang sv $ ~/src/ssmping storhaugen.uninett.no
>     ssmping joined (S,G) =
>     (2001:700:1:7:290:27ff:fe22:7186,ff3e::4321:1234)
>     pinging S from 2001:630:d0:111:250:fcff:fe6a:42b3
>     unicast from 2001:700:1:7:290:27ff:fe22:7186, seq=0 dist=20 time=61.8ms
>     unicast from 2001:700:1:7:290:27ff:fe22:7186, seq=1 dist=20 time=63.9ms
>     unicast from 2001:700:1:7:290:27ff:fe22:7186, seq=2 dist=20 time=57.3ms
>     multicast from 2001:700:1:7:290:27ff:fe22:7186, seq=2 dist=12
>     time=59.7ms
>     unicast from 2001:700:1:7:290:27ff:fe22:7186, seq=3 dist=20 time=55.8ms
>     multicast from 2001:700:1:7:290:27ff:fe22:7186, seq=3 dist=12
>     time=59.2ms
>     unicast from 2001:700:1:7:290:27ff:fe22:7186, seq=4 dist=20 time=55.9ms
>     multicast from 2001:700:1:7:290:27ff:fe22:7186, seq=4 dist=12
>     time=59.2ms
> 
>     This means that multicast is working, but it took about 2s for the
>     multicast tree to be built (the 2 first packets got lost).
> 
>     You can also see that there is 20 unicast hops from the source, but
>     only 12 multicast hops. And that the delay is somewhat larger for
>     multicast.
> 
>     At the server I see this:
> 
>     received request from 2001:630:d0:111:250:fcff:fe6a:42b3
>     received request from 2001:630:d0:111:250:fcff:fe6a:42b3
>     ...
> 
>     Note that it support both IPv4 and IPv6. It used IPv6 in this case
>     because hostname is registered with both A and AAAA.
> 
>     You are welcome to try both client and server. You can try to ping
>     ssmping.uninett.no or some other ssmping servers to check that you
>     can receive IPv4 or IPv6 SSM from them. If you tell me your server
>     name I can also try to ping you.
> 
>     I have a web page for ssmping at
>     http://www.venaas.no/multicast/ssmping/
> 
>     You can find a list of public servers to ping there. I could also
>     list yours if you want.
> 
>     At this web page you also find the sources. It's quite simple to
>     build on Linux and relatively simple on Solaris. Those are the
>     tested platforms so far. I would be happy if people tried it on
>     other plaforms, but note that on the client side, you need a
>     system that supports the source filter API, that speaks IGMPv3 or
>     MLDv2 and of course a router doing that a well.
> 
>     Well, have a look at the web page if you're interested. And I'm
>     happy for any comments, questions ets.
> 
>     Personally I've already made use of this tool for some debugging.
> 
>     Stig
>