All things related to multicast

[Alan Crosswell <>]

Most institutions pay for I2 so scientists can transfer massive amounts of data 
via unicast -- not for video edutainment.  I don't see real science being done 
using multicast with perhaps the exception of the Access Grid meetings (and we 
don't have an AG node here).  All the interdomain multicast we've done has been 
essentially P.R. oriented videos (commencement, musical performances, etc.).

I can tell you first hand there are a lot of unsolved problems mostly having to 
do with L2 multicast working correctly and not flooding hundreds of legacy cat3 
10/half ports.   It is also hard to set up and hard to keep working reliably -- 
when multicast breaks its very hard to debug compared to unicast.  There's also 
paranoia at our medical school that has led to a campus firewall there and not 
much liklihood of them opening up for multicast anytime soon given they don't 
even want to do unicast with the rest of the world anymore.  Several 
schools/departments who run their own building networks have such old L2 
equipment they can't even support multicast.  They see no compelling reason to 
upgrade hardware just to support multicast.  It works good enough for unicast.

Most campus IT staff are very busy these days just dealing with eradicating 
Windows viruses.  Some are probably happy they didn't have MSDP running when 
Sasser hit.

I think the only thing that will push multicast out there is getting commodity 
ISPs to deliver it on behalf of the big entertainment content providers (like 
CNN) and the economic case doesn't seem to have been made for that.  I have to 
pay Realnetworks extra to enable "scalable multicast" on my Helix server so I 
wasn't even able to turn it on like I had hoped.

Life sucks in the land of multicast.  But we'll keep pushing for it.
/a

Richard Mavrogeanes wrote:
> In the "Why don't we use multicast more often" department, we have just concluded a 5 
> day interactive video broadcast from the bottom of the Atlantic ocean (the mission continues at 
> www.explorethesea.com, but the interactive portion is over).  I received at least 25 messages 
> from folks trying to tune in to the multicast but could not. Quite a few of these were along the 
> lines shown in the message below, where they have I2 connectivity but cannot receive multicast 
> due to "cautious network engineers".  I suspect we make progress in having uses 
> complain that they cannot participate, thus putting pressure on the staff to allow multicast 
> thru, but I still see lack of availability at the user level to be a major problem.  Personally, 
> I find it amazing that institutions pay the very expensive I2 connectivity fees but, what, use 
> the connetion for high speed email?  In the next few weeks, the interest in multicast is likely 
> to increase as we broadcast much of Dr. Ballard's return to
the Titanic, live, via multicast.
> I think it would be great if someone in this group could create/sponsor a multicast 
> IMPLEMENTATION FAQ targeted at members IT staff. We don't need a "what is multicast" 
> but a "how to" FAQ. I further think this group might form and post a volunteer list of 
> email and phone numbers that member's  local IT staff could turn to for help in setting up their 
> networks (I cannot volunteer mostly because I do not have I2 access).
>
> It would have been useful if I could tell this below user to tell their IT 
> staff to contact a designated member for help...
>
>
> > Cautious network engineers 
>
>
> > > > "Richard Mavrogeanes" <> 5/21/2004 5:21:02 PM >>> 
> >
> > No, all video is sent via multicast. It's hard to think of a reason why 
> > you would not have it enabled unless you have very old equipment. 
>
>
> >       -----Original Message----- 
> >       From: J 
> >       Sent: Fri 5/21/2004 6:15 PM 
> >       To: Richard Mavrogeanes 
> >       Cc: D 
> >       Subject: RE: Explore the Sea Internet2 Video 
> >       
> >       
>
>
> >       We're connected to Internet2 but do not have multicast enabled. 
> > Will the Vbrick work? What firewall protocols, ports do you need? 
>
>
>