[al_bundling]

> Part of the problem is adding capacity in an HFC network is expensive and difficult

Sure, but no more than doing VDSL, which is basically the same thing for ADSL as splitting nodes in a HFC network. A FTTC+VDSL upgrade is about $400 per subscriber which is $17 per month on a typical 24 month contract. That's quite doable and typical network life cycles are much longer, which brings the cost further down.

[Aloha]

I don't fully agree.

When you build out VDSL, you're expecting to provide service to every customer in range at a fixed oversell ratio, if you need more bandwidth you can turn up additional fibers to the node, at the worst, split the mux down to smaller numbers of subs per, but the aggregation point never changes - it's always at the RSLAM.

With cable, the point of aggregation is at the subscriber prem, just like thinnet - the only way to get more bandwidth to the subscriber is to decrease the size of the broadcast domain by adding another node.

It's basically my contention that like most wireless networks the pinch point is access layer, not in the backhaul, HFC networks are much like wireless networks, they have a fixed amount of RF bandwidth shared with N subscribers over a given area - being that the amount of spectrum a given area can use is fixed (by licensing or by bandwidth limitations in the cable) the only way to handle more subscribers in a given area is to decrease the number of subscribers per network element, in short, add more sites, or nodes.