All things related to multicast

["Richard Mavrogeanes" <>]

Bill,
 
If *we* are those with high speed network connections to the the I2 that 
support multicast, then I'm afraid I'm not a *we* 
and that is part of the problem.
 
If the value of the network is equal to the square of the number of users, 
then the multicast network is not very valuable.  
 
It would be fun to have a multicast video conference with the members of this 
group, but after a trial I suspect it would
be little used.  I fear that we would simply pat each other on the back, 
marval at how good it is, and then not use it again 
for a long time. I've built such a system and it is in use in enterprise 
networks today (it uses VBrick appliances, and is therefore
not free, but those with these boxes might be interested in testing it).
 
I think the real interest would be in getting others to engage, but there is 
a problem because multicast does not generally
reach out to non-techie users.   The I2, for example, goes to ~203 
institutions and (trust me on this) the reach of multicast within 
those organizations is spotty at best.  
 
We are multicasting live undersea reseach on the I2 (www.explorethesea.com), 
including Dr. Bob Ballard's return to
the Titanic, live on the I2 (currently, we are replaying a video from last 
year for testing and I've be most interested if the
folks on this list can see it...PLEASE let me know). 
 
The marine science departments at Universities and the K-12 folks who "think" 
they have I2 access quickly 
discover it does not work.  To some degree, this is all part of a grand 
plan...provide compelling content
that makes users complain to their local IT staff.  We did this last year 
with the Black Sea project too (www.expedition2003.org),
but learned that too many local IT guys tell their users to go away and be 
happy they have unicast.  It's not completely their
fault...their network are often a mix of legacy hubs and uncontrolled wild 
growth. What I find is that the IT staff is very fragmented 
in Universities.  Sure, the IT guy for the science dept. is willing to fix 
it, but the IT guy in the main building who 
controls the access point has no interest. 
 
I think that if we really want to see multicast take off, then there needs to 
be a great public tunneling service so no one needs to be
left out.  Local IT staff may then become motivated to deploy multicast as a 
bandwidth-saving measure when their users are sucking up
lots of high bandwidth unicast.  To many, multicast is "revolutionary" and 
what may work best is "evolutionary" solutions that
enable a migration.
 
I'd love to see multicast-to-unicast reflector service on the I2 that offers 
all mbone/I2 multicast content as unicast, but that times out
after 60 seconds with a message that says "Sorry, your unicast service is 
consuming too much bandwidth.  Multicast service is
available to you without limitation. Please contact your local IT 
department".  Then all it takes is plenty of compelling content, and
there is a chance such content will appear when there is truly an audience 
big enough.
 
My 4 cents, this time.
 
 
rich
 
 
 
 
 
 
 

        -----Original Message----- 
        From: Bill Owens 
[mailto:]
 
        Sent: Thu 5/13/2004 5:07 PM 
        To: 

 
        Cc: 
        Subject: Re: Why don't we use multicast more often?
        
        

        On Thu, May 13, 2004 at 04:24:36PM -0400, Richard Mavrogeanes wrote: 
        > My two cents: 
        > 
        > Multicast is not used more often because: 
        > 
        > 1. The default condition of virtually all routers is to disable 
multicast. 
        . . . 

        All true, and I certainly know that multicast is not an easy thing to 
configure, manage and repair (or even understand!) but I'm intentionally 
preaching the choir here. I wasn't asking why Joe Public doesn't use 
multicast more often, I was asking why *we* don't use it more often. 

        My application, weekly recurring conference calls with a standing 
group of people, all at Internet2 sites, all of them advanced network users, 
seems like an ideal place to use multicast a/v tools - and yet, we don't. 
There must be dozens of similar conference calls every week; heck, Internet2 
has their own conference system, and they wouldn't have bothered if they 
didn't use it a lot. Isn't there something wrong with that picture? 

        Bill.