They're hardly out of the tech headlines these days - Amazon - and they're back in them again with their latest offering, called "Amazon Video on Demand." I have to admit I like the name, I'm a big fan of stating the obvious and it's a much better name than calling their new service "Wendy," or some meaningless made-up piece of with-it jargon. It's actually a clever service, too, they've given it plenty of features and done everything they can to make it idiot-simple to use. It's possibly even easier than going to YouTube to find something to watch. So why do I think they're pushing their luck? Why do I think they could fall flat on their faces with this?

The short answer is bandwidth. Amazon are only the latest to jump on the video-on-demand bandwagon, albeit theirs is the neatest offering yet. But they all require users to download vast quantities of streaming data to watch a film or television programme and the Internet is already creaking under the strain, even before this service goes live.

Comcast is the first network provider to crack. Unfortunately, their chosen method of dealing with the problem is particularly clumsy and has enraged a lot of free-speech advocates who have now complained about them to the US Federal authorities, the FCC. Comcast have targeted the biggest source of bandwidth usage and has penalised those of its customers who use BitTorrent, a file-sharing site. Anyone can share audio and video files with anyone else on BitTorrent, but Comcast is slowing down the response rate for its own customers to try and reduce the amount of bandwidth being used at peak hours. They are developing software that will do this for any user who is moving large amounts of data at peak times from any site, but for now, this is their cheap-and-cheerful solution. The complaint is that Comcast are wrong to target a specific site in this way as it impinges on the rights of their customers to visit whatever (legal) web sites they want. Frankly I agree with the complainants, Comcast have been clumsy, but the lack of bandwidth is the underlying problem and it is only going to get worse.

So this is the background to Amazon's new video-on-demand service. There is a colossal amount of material out there, and we have content creators and owners as well as broadcasters competing to set up video-on-demand services so we can access it all. I agree this spells the end of the local Blockbuster store, but who is going to be happy watching a gripping movie that is intermittent? Network providers will have to introduce bandwidth limits at peak times. That's not a prediction, it's a necessity, and they're talking about it now. Technically this means that blocks of data will be delayed and bandwidth will be shared between other customers using a lot of bandwidth at the same time. In practical terms, this means that whatever you are watching will come in fits and starts, with gaps of a few seconds or even a few minutes between segments. It will not be possible to increase network capacity in time to meet the demand that Amazon and many others including Sky, Channel 4, the BBC, are going to create.

The storm clouds are gathering and now is not the time for Amazon to push their boat out onto these particularly choppy seas.