This is a hot topic for all sorts of reasons both in the UK and in the US, and OFCOM recently made some comments on it as well. I'd like to try and explain it simply enough that even Pauline does not have to stop reading after the first paragraph...
Basically, ISPs sell people Internet access. Simples.
The problem is that the term "Internet access" is a bit vague - what does it mean? An ISP cannot, for example, guarantee connectivity or even speed to any specific endpoint on The Internet. That is because to get there means going through other ISPs. If you want to get to your favourite web site and the site is down, or just slow, then that is not the ISPs fault. There are a lot of ways bit of the Internet may not be working in various ways for all sorts of reasons and that is not something the ISP can control.
So what do ISPs provide, or perhaps more to the point, what do customers of ISPs expect.
Well the main thing is for everything to be treated fairly, whatever that means. It is not too hard to pin down examples where that is not the case. If, as an ISP, I was to do a deal with ITV and clamp down BBC iPlayer so it is unusable, that would be bad and unfair. That sort of extreme is what this is about.
So what about Sky Anytime+ which can only be accessed if you have a Sky broadband line? Does that mean BT, for example, is not providing access to the whole Internet as its customers cannot access that IP based service?
The problem is that ISPs do have various types of "traffic management" for all sorts of reasons. The main one is that people can hog all the bandwidth. This is like having a hose-pipe ban - you want to stop the handful of people using all the water on an "unlimited" (i.e. un-metered) tariff. Is that against net neutrality - some say yes. But if ISPs cannot clamp torrents then they give everyone a bad service, or they have to charge more or charge for usage (like we do). Some people want a simple cheap fixed cost service and don't want to pay for usage. For them, a service that does clamp heavy users it excellent.
One thing I think is very important and that OFCOM did pick up on is transparency. ISPs should tell customers up front what they do. If you are buying a cheap fixed price Internet service you actually want an ISP that filters all the high traffic torrents that screw up your Internet - well most people do - the few wanting to run torrents don't want that. Either way, and ISP that tells you up front what they do is ideal as both types of customer as they know where they stand.
Another thing OFCOM did say is that anyone blocking or restricting access to legal content should not be allowed to say they are selling Internet access. That is a principle I do agree with. However, it has some interesting implications.
Firstly it is a nightmare to define is anything is treated in some preferential way, or conversely in a way that is not, and hence "restricted" in some way. Our mail servers are on our network and so will have better connectivity than competing mail servers. Is that wrong? It would be mad if we had to host our servers on a separate network to comply with net neutrality rules.
Similarly we have peering with people like BBC. Is that preferential treatment? Technically, for some levels of load on our network and some types of measurement it is. Should we not be allowed to peer with anyone? That again would be silly.
These are edge cases, and a tad technical, but trying to work any rules on net neutrality have to allow for these but somehow outlaw the more overt commercial preferences that could come about and be considered bad somehow.
There are then a few fun side effects of the idea of not blocking or restricting legal content - like BT's newzbin block. That site has legal content and services even if only the image of their own logo and their front page. That legal content being blocked (even if it is because of a court order) means BT could not sell Internet access under the OFCOM proposals. Ooops!
Of course you could talk about all content that an ISP is not legally required to block. That would get BT out of problems, except for the fact the the IWF list (child abuse) is not something ISPs are legally required to block and you can be sure at least some content on the block list is not illegal to access even if just a css style sheet on a site. Again, the devil will be in the detail.
So all the net neutrality is at serious odds with court ordered and voluntary blocking of some Internet services. That is not a huge surprise to be honest.
Then you have the real fun - any ISP not providing IPv6 would be blocking access to some legal content like www.loopsofzen.co.uk and so not allowed to sell as Internet access. We like that one :-)