If you believe many of the posters on internet discussion forums, “in a few years, things like Sky and Freeview won’t matter, because we’ll all be getting our TV over the internet”.

Certainly, the accepted wisdom of many is that TV may arrive over the internet in the future, rather than the airwaves.

But is that going to happen? How will it work? And, perhaps more importantly, what do people mean by ‘Internet TV’ and ‘IPTV’?

In this feature, we’ll explore the technologies, and their alternatives, and look at what it could mean for the future of UK television.

Given its astonishing growth since the launch over Christmas 2007, it’s no surprise that for many people in the UK, the BBC’s iPlayer and internet TV are more or less synonymous ­ if you want to watch the same programmes you see on TV, when you want, it’s the best source.

There are alternative sites such as Youtube ­ which uses the same Flash video technology for streaming ­ or Joost, from the creators of Skype, which has a reasonable range of niche material, but when it comes to watching the latest programmes legally and in decent quality, the iPlayer is the biggest hitter.

It’s not the only game in town, however; ITV has its own Catch Up service, and there’s Channel Four’s 4OD as well. There’s a mix of technologies available, with 4OD using ­ like the original version of the iPlayer ­ a peer-to-peer (P2P) download service called Kontiki, so that programmes are ultimately stored on the viewer’ s PC, rather than streamed in real time.

In fact, the BBC still offers this download option, but it’s been largely eclipsed by the streaming version of iPlayer. The streaming works on more platforms than just Windows, as well as not being reliant on installing a P2P service on your computer, something to which many users have objected, and which doesn’t find much favour with ISPs, either.

That, ultimately, is something of a shame as using a P2P distribution method is arguably a more efficient use of bandwidth than having millions of people trying to stream a programme at the same time from a single source, and could ease at least some of the problems ISPs are currently seeing.

IPTV or Internet television?
While services such as iPlayer, 4OD and Youtube might provide ‘television’ you can watch over the internet, they’re not IPTV services in the strictest sense. This is where things can get confusing, even for the tech-savvy user.

But, as more companies seek to offer TV programmes online, it will become increasingly important to understand what’s on offer, and how it’s delivered, to ensure that you don’t fall foul of download caps, bandwidth limits, or simple incompatibilities.

So, what exactly is the difference, and does it matter? To some people, ‘IP television’ simply means TV delivered over the internet; and the BBC iPlayer or Youtube certainly fall into that category. But to many, it’s a more tightly defined set of protocols that make up a ‘true’ IP service.

The difference, perhaps, is similar to the way in which people will refer to internet telephony, and include Skype’s proprietary system within that, but when they talk about VoIP, many will tend to assume you’re discussing services that use open protocols such as SIP, that allow interoperability.

Similarly, when it comes to TV over the internet, you can consider the popular services at present to be analogous to Skype ­ they’re simple to get to grips with, on the whole they ‘just work’, and they don’t use the same standards as a ‘true’ IPTV system.

In the strictest sense, an IPTV system is one that uses specific standards to deliver TV to a dedicated set-top box, using for example MPEG2 or MPEG/AVC video in ‘transport streams’, ­ the same sort of wrapper that is used in cable, satellite and terrestrial TV boxes. But instead of being wrapped up in a broadcast medium, it’s delivered via a TCP/IP connection.