How do you put a TV station on the Mbone? (was: Royal Wedding...)

Octavio Alvarez alvarezp at
Fri Apr 29 21:46:23 UTC 2011

On Fri, 29 Apr 2011 10:48:51 -0700, Jay Ashworth <jra at> wrote:

> ----- Original Message -----
>> From: "Rubens Kuhl" <rubensk at>
> And that's the snap answer, yes.  But the *load*, while admittedly
> lessened over unicast, falls *mostly* to the carriers, who cannot anymore
> bill for it, either to end users, providers, *or* as transit.
> Will they not complain about having their equipment utilization go up
> with no recompense -- for something that is only of benefit to commercial
> customers of some other entity?

Why would they bill someone for a service they are already providing?

So the first user in a router tunes to a multicast stream. Consumption
for the ISP and all the routers in the chain to the source: same as if
it were a unicast stream. Then a second user tunes to a multicast
stream. Cost for the ISP: zero.

So 5000 users connect each to a different multicast source. It is the
same as if they all used unicast. The utilization can never be
worse than a unicast-only network.

So maybe I'm oversimplifying, but I fail to see a problem, only an
artificial one created for the sake of it. Other than the potencial CPU
load of the routing protocol, I even fail to see the commercial value of
not providing multicast.

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