Let's take an example. I'm a small provider. I have an OC3 to FooNet and an OC3 to BarNet and I get full transit on both. I sell a DS3 to someone.
Now you can argue that I should just eat this cost.
Not quite my argument, but yes, I can argue this (see below).
In any event, it has always been my position that where possible and within reason, ISPs will be most competitive (and the Internet will remain the most stable) if they can develop and implement pricing models that charge their customers based upon the actual cost to provide the customer with the service.
Precisely the thoughts I intended to provoke. Assuming the group members are other customers of foo and/or bar, then foo and/or bar are charging both you and those customers (essentially charging you for something already paid for). Even if foo/bar is just routing to some other network and just passing on their overcharge to you, the argument stands that someone is charging twice for the same traffic. While it might be true that you have a cost based on your transit/peering agreements (i.e. the pricing model), the argument stands that multicast doesn't cost more. The truth is, it costs less. You're just being charged more because you accept it. And to recoup your cost, you consider passing it on to your customer (who with this model concludes multicast isn't cost effective). I haven't begun to conceive a model that works to everyone's satisfaction, but it's plainly obvious the existing model doesn't work in favor of multicasting. You can bet that whoever is pocketing the overcharges is not going to stop on their own accord. But until we come up with the right model, the profit potential of unicast is going to remain an obstacle to the general acceptance of multicast. -John