Re: VOIP to replace VM copper wires.
 

Would there be any benefit for VM in making their TV service IPTV and putting all three services down their broadband?

Re: VOIP to replace VM copper wires.
 

If it was IPTV, it would have to be multicast - and I'd guess the overhead would quite likely be higher than for the existing multiplexed streams

Re: VOIP to replace VM copper wires.
 

Nope. Wouldn't think so. VM could make for more spectrum availability by making their TV service a "pull" rather than "push" system, where the node only supplies the channels that are requested by the boxes in the same way as OD operates now.

Re: VOIP to replace VM copper wires.
 

I would imagine that it would be IPTV - but only the channels being watched on a given node would be present. For example, there might be only a few people on a given nodal area that are watching a particular channel, so it would be multicast. As soon as that number drops to zero, the channel is temporarily removed from the multicast stream to that node. Dynamic edge-QAM would reprovision the bandwith at that moment for broadband, providing a temporary speed boost.

Part of me thinks this might not happen quite how I'm imagining it however, because if you take it to an extreme, the variation in bandwith available at any one time on a single nodal area might be such that it becomes difficult to sell a certain fixed speed broadband package (as being that speed) since it varies so much depending on how many downstream channels are being used for multicast services. The worst case would be that everyone on the node is watching a different channel at the same time.

You would either have to overpromise and then allow the B/W to drop as more TV channels are assigned multicast bandwidth, or give more Internet bandwidth than advertised up front and reserve some for TV - but that's effectively what happens now by having fixed multiplexes.