What is net neutrality?
NET neutrality is the idea that all internet traffic should be treated equally by broadband providers regardless of its origin, destination or content.
Supporters say ISPs shouldn't prioritise any one form of content over another or block any legal content.
The battle is fierce, with major names like Sir Tim Berners-Lee, inventor of the World Wide Web, weighing in on the issue.
According to Berners-Lee, any erosion of net neutrality is an attack on the founding principles of the internet. And he should know.
Groups of advocates, content providers and smaller startups also support free access to an open internet.
But opponents say enforcing net neutrality would stifle innovation and the evolution of web services by forming a legislative firewall around companies attempting to make money online.
Do we have a neutral net at the moment?
Depending on who you listen to, the internet's neutrality ranges from just south of Switzerland to about as neutral as a chap standing in the Kop with LIVERPOOL tattooed across his forehead.
ISPs argue the exponential growth in online traffic means some form of web traffic management is necessary.
All the big ISPs now block illegal filesharing sites and provide parental controls.
And ISPs can and do block some services while prioritising others; a policy that campaigners fear could lead to a multi-tiered system, where those who pay more get priority.
Let's take a look at these points in a bit more detail.
Traffic management: throttling and fast lanes
In the UK, traffic management and fair use policies are the major factors affecting net neutrality.
Broadband providers say they manage their network bandwidth as a way of maintaining a particular quality of service for the majority of their customers. Sometimes this extends to prioritising specific content.
For example, activities like emailing, gaming, browsing and listening to music might be prioritised over bandwidth intensive applications like streaming video and file sharing.
So some people using larger amounts of data during peak times can find their connection speed deliberately slowed; this is known as throttling.
Providers can allocate extra bandwidth to traffic to ensure it's properly delivered; this is known as a "fast lane" and is often used for TV streaming services.
All the major providers - under the auspices of The Broadband Stakeholder Group - signed an Open Internet Code of Practice in July 2012.
While they all have different traffic management policies, they have to communicate these clearly to customers.
ISPs agree they'll "not target and degrade the content or applications of specific providers".
The whole code is available here [pdf] and was updated in May 2013 to clarify that "signatories would not be infringing the code if they deployed content filtering".
Blocking: court orders and parental controls
Few net neutrality advocates would argue that illegal content shouldn't be blocked online.
From 2015 ISPs can send letters to households suspected of downloading files illegally.
Net neutrality supporters are more worked up about plans to drastically increase households' use of parental controls, with ISPs blocking legal content by default.
Organisations like the Open Rights Group argue this kind of blocking is an affront to the open internet and could accidentally block many legal sites.
Paying for play: a multi-tiered web
In 2014, Netflix paid American ISPs millions of dollars to have their video streaming service prioritised.
The introduction of priority for content providers with the deepest pockets has less affect on UK users today.
But net neutrality advocates say big sites benefit and internet users will have to fork out extra to ensure a decent quality of service.
In February 2015, America's Open Internet Order banned paid prioritisation, along with blocking and throttling.
Consumer groups fear that setting providers loose will create an internet where, in the words of Robert Hammond, Head of Digital Communication at Consumer Focus, "...big bully boy companies rule, pushing out smaller websites and restricting consumers' choice."
However, Ofcom and the EU agree that as long as users are informed of how their traffic is prioritised - or not prioritised, as the case may be - a little traffic management is fine.
A spokesperson for the UK's Department of Communications said that it supported proposals from Europe and Ofcom which would leave broadband providers free to prioritise traffic as they see fit:
"A lightly regulated internet is good for business, good for the economy and good for people."
That said, it was the BBC who initially took a stand against paid content, putting themselves at odds on the matter with the UK Government and European Council.
They refused to pay ISPs to guarantee the delivery of the BBC iPlayer service, instead choosing to name and shame any providers who were detected to be slowing the streaming service in favour of other content.
How net neutrality affects you now
In the UK, ISPs have a lot of say in how they manage traffic, but they also have to communicate what they are doing; for broadband users this transparency can only be a good thing.
We've covered the ISPs fair use and traffic management policies in this guide.
In fact ISPs argue it should always be up to the market to decide who provides the best service, with people free to choose whichever they see fit.
This is partly why the European Commission have long been undecided about making laws around net neutrality.
If the EU introduces laws, they're likely to be minor and would make little difference to net neutrality in the UK.
America has already gone much further; its Open Internet Rules effectively make most of the principles of net neutrality law.
But in 2015, the UK's House of Lords suggested broadband should be reclassified as a utility, so there's still a possibility net neutrality could become reality here too.