Multicast Traffic on Backbones

Essentially every major network operator has one network engineer
who can set up multicast for customers. The problem is very few
networks have figured out how to turn multicast into a commercial
product. So if you don't find that one engineer, you are out of
luck.

Unicast streaming may be less efficient, but most providers can figure
out how to charge for it and make it a supported product. Unfortunately
some folks have confused multimedia with multicast. While I've seen
many multimedia multicast applications, I haven't seen one which can't
have its essential elements replicated by unicast streams. Is there
a killer-ap for multicast?

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Unicast streaming may be less efficient, but most providers can figure
out how to charge for it and make it a supported product. Unfortunately
some folks have confused multimedia with multicast. While I've seen
many multimedia multicast applications, I haven't seen one which can't
have its essential elements replicated by unicast streams. Is there
a killer-ap for multicast?

Multicast is an extension to Unicast. I don't think there is a multicast
application that cannot be run over unicast protocols as well. Our
application for multicast will be:

  live broadcast of academic and technical classes
  live broadcast of sporting events
  live broadcast of campus television station
  live broadcast of campus radio station
  video conferencing across multiple locations

All these things CAN be done using unicast, but multicast is much more
efficient.

=== Tim

Sean Donelan wrote:

While I've seen many multimedia multicast applications, I haven't
seen one which can't have its essential elements replicated by unicast
streams. Is there a killer-ap for multicast?

24x7 broadcast media is the obvious/visible application.

HOWEVER, most of the 24x7 media sites (CNN, etc.) are doing on-demand
video, rather than streaming a constant feed. Content providers are
treating the Internet like a VCR instead of treating it like television,
and multicasting has very little value in a VCR model.

Whether or not the Internet is suitable for a television model is unproven
at this point. I would assume that it is, and that it is likely to
eventually be used in this capacity. But it isn't yet.

There is probably a chicken-v-egg thing going on here, too. On the one
hand, content providers aren't offering 24x7 multicast feeds because there
isn't enough multicast access at the end-points. Meanwhile, carriers
aren't offering multicasting because there's no demand for it from the
content providers.

Apart from 24x7 broadcast there isn't an obvious killer app. Most of the
multicast activity is going on in the local/admin scope, with discovery
and management protocols.