Fixed Rate
Remember the halycon days of 56k modems on an 0845 number? Back then "unmetered" internet was but a dream, but the charging was fair. You paid by the minute, if you were on for 10 minutes you would be charged the connection fee (5p) and 1p a minute, so it cost 15p for 10 minutes internet access.
Then game 0808 numbers and "unmetered" internet, 56k modems could be connected without having to pay BT £300 a quarter, of course there were tiers, 5 hours a week, 50 hours a week and you paid for what you used.
Then along comes ADSL and again the market changed, now you had "true" unmetered internet access, able to be online 24/7 without your ISP cutting you off every 2 hours and 30 minutes of engaged tones.
The problem with that was there were no tiers, someone who only used the internet for an hour a week sending emails, was paying as much as someone who used their DSL 24/7 downloading every hentai they could find.
Therein lies the problem, ISP's have to reintroduce tiers. If you want to download tentacle squid machine fifteen from some Japanese p2p application, you should be willing to pay your fair share, you shouldn't expect to be subsidised by Granny Smith who sends photos of her cats and rude turnips to Uncle Peter in Australia.
The ISP model does have to change, the entire range of products have to change, the people who use their internet connections have to start paying for what they use. We have to go back to the 0845 model, only instead of being charged per minute, we are charged per GB.
Yes there would be lots of "gimme my MAC! X ISP is offering unlimited internet access!" at the start, but then X ISP would go bankrupt unless they switched to a per GB pricing model, if you want to download 100GB/Month, you better be prepared to pay £200 for it instead of £8.99.
Would this change the market? Yes it would, companies which invest heavily in LLU and can support an "unlimited" model would start to offer heavy competition to BT's model, BT would be forced to change their network to remain competetive with LLU suppliers, ISP's would be able to lower their costs per GB and pass the savings onto their customers and we would end up with a healthy broadband infrastructure which is able to cope, not only with current SD content, but future HD content where bandwith needs will double? Triple? Quadruple?
If ISP's are unable to cope *now* with the issues that the iPlayer had introduced, what hope do they have on future projects? None. they need to stop blaming the BBC for what is pretty much the fault of their own creation, they need to start fixing it and introducting fair pricing, and until they actually put their house in order, the industry as a whole will suffer quite badly.