All things related to multicast

[Richard Mavrogeanes <>]

We've done many systems like what you propose.  Perhaps
the best example is at University of Arkansas, but here
is a collection of case studies, almost all via multicast:

http://www.vbrick.com/casestudy.asp


With regard to desktop cost, a site license for the desktop
player is far less costly than you may think.  Vendors have
some flexibility for MPEG-1 clients, but MPEG-2 requires royalty
payments and that cannot be avoided.  Still, it is far less
costly than alternatives.  In our case, we even bundle a s/w
license in with our appliance (http://www.ethernetv.com).

Frankly, if your network is 100M switched, and you support
IGMP V2 (I mean, really...you can't always trust what your
switch vendor tells you), you can accomplish what you described
in about an hour.

Indeed, our customers like the fact that they have deployed a
multivendor standard, and are not locked into a proprietary solution.
Players tend to differ in how the stream is selected, and some vendors
like to include proprietary "enhancements" that, at least to my way of
thinking,
are unnecessary.  But if you save a MPEG stream as a file, then you can
edit it, rebroadcast it, etc. via any number of vendor's products.

Hope this helps,

Regards,

Rich Mavrogeanes






-----Original Message-----
From: Wilson Dillaway 
[mailto:]
Sent: Friday, February 22, 2002 6:00 PM
To: Multicast Working Group
Subject: question concerning MPEG-2 distribution of student TV station


     Tufts University has not done much with multicast
so far, but the TUTV student television station, which
currently broadcasts only over the campus analog cable
TV network, would like to experiment with MPEG-2
multicast transmission to all desktops on campus.  We
think a 24-hour, 7-day MPEG-2 multicast stream would
be a great way to debug our router structure (not to 
mention the other benefits!).  Does anyone have 
experience with this application (continuous 
broadcasting to a large audience) and can share some 
impressions?

     We are reasonably confident about our overall
infrastructure (mostly 100-switched to the desktop;
gigabit ethernet between buildings; Foundry routers
in the backbone).  To minimize the support 
implications, we would like to purchase an appliance-
type MPEG-2 encoder rather than build something from
generic servers and software.  (Happy to have 
recommendations on brands and models.)  Alot of the
MPEG-2 products on the market seem to be more focused
on the point-to-point bidirectional videoconferencing
need rather than one-way broadcasting, although I 
guess they can do both.

     For this particular application, we would want to
distribute client viewing software that could display
full-screen video (or partial-screen video in a window,
at the viewer's discretion).  Is there such a thing as
a generic MPEG-2 decoding client?  Every vendor seems 
to have its own proprietary software product, which
the viewer must download and install.  That's a 
manageable problem, but the bigger issue is that these
proprietary software products are not free.  I have no
problem with the software producer being fairly 
compensated for their work, but an enterprise-wide
site license for this software can be many times the
cost of the hardware encoder.  For this particular 
application, the students may only attract hundreds
of simultaneous viewers, at least to start, but there
is no easy way to make software available on a more
restrained basis than enterprise-wide.

     Anyone have any experience with this, or any 
thoughts to share?

      Wilson Dillaway
      Tufts University