The Atlantic sea-floor is one of the few places where the information superhighway lives up to its name. The optical fibres that carry internet and phone traffic between the US and the UK might lie at the bottom of the sea, but they really are the fast lane of the web. Text, images and movies zip along these connections at the kind of speeds that, if we could access them at home or in the office, might justify some of the internet hype. But by the time data reaches our monitors, the highway is more like a muddy track.
As the internet gets more sophisticated, so the need for faster connections grows. Home users and the coming generations of mobile phones will consume bandwidth like never before. Work out a way to extendthe high-speed connections of the internet backbone into our homes and you'll find yourself very wealthy.
For home users, the highway stops with your local internet service provider (ISP). Big ISPs have a huge broadband connection to the backbone of optical fibres that sends internet data around the world. But home users connecting to ISPs use a link built for something totally different - the copper wires designed to carry our voices around telephone networks.
Copper wires carry digital signals just as well as analogue telephone conversations, but they're not up to shipping the kind of digital content that we want out of the internet. You can do some clever things - BT's new OpenWorld service uses ADSL technology to increase connections speeds by roughly tenfold - but fundamentally there is only so much bandwidth you can squeeze out of a metal wire.
Start doing the sums and it is clear that copper is not the way forward. ADSL offers 512kbps to about 6Mbps, a big improvement on the 56kbps most home users currently have. But high-quality full-screen moving images will need more like 30Mbps, leaving ADSL up to 10 times too slow. Cable modems, the main alternative to ADSL for home users, do not offer significantly more speed.
ADSL and cable might be the only way to improve your access right now, but over the other side of the pond, companies are pouring billions into what many believe is the only system capable of satisfying our need for bandwidth. After years of dithering, the US telecommunications giants are starting to extend the optical fibres that form the backbone of the internet to the "last mile" services that connect local ISPs to homes.
Piping optical fibre into homes isn't a new idea, but home use of the internet looks set to justify the huge costs of installing such connections. US phone company BellSouth trialled a video-on-demand system more than 10 years ago. Consumers liked it, but not enough for them to want to pay to dig up the roads to install it.
A decade later, the internet could make all the difference. Soaring home use and the promise of mobile web appliances vastly superior to today's Wap phones have persuaded a slew of telecommunications companies to get out the pneumatic drills and start laying new optical fibre networks.
Here in the UK, broadband access remains the preserve of universities - which have their own dedicated network - and companies able to afford the huge fees charged for megabyte per second T1 connections. And if the cost of fibre networks puts investors off for as long as it did in the US, the frustration of home internet use could be with us for several years to come.
In the meantime, UK companies may look instead to some of the more imaginative solutions being touted by smaller US outfits. TeraBeam, for example, has reasoned that laying fibre to carry light is unnecessary; light can travel happily through air without a guiding cable. The company plans to install an optical transmitter on a suitably high building in Seattle and beam signals straight through the windows of nearby offices. The £18,000 a month subscription fee means it will be available to business users only, but those lucky few will enjoy a 1 gigabyte per second connection.
Home users are more likely to benefit from a range of schemes to construct what US businesses call "high towers". In the case of the collaboration between Nasa and AeroVironment, the "tower" is actually a solar-powered pilotless plane that circles endlessly above cities. Named Helios, the plane acts like an extremely tall radio mast, capable of avoiding hills and buildings and beaming signals straight onto receivers on the roofs of houses.
Helios has already made its first flight, but more work is needed on the solar cells and the batteries to power it at night before it can start full service.
A lower-tech but perhaps more feasible high-tower solution is offered by old-fashioned airships. The Sky Station International consortium plans to build a fleet of 250 airships in Italy, the first of which should be airborne by 2002.
Once afloat it will hover 21km above cities and, according to the company, deliver 10Mbps connections - roughly 200 times faster than most current home links.
Whether these schemes will work remains to be seen. What is not in doubt is that our hunger for bandwidth will continue to grow, as content becomes increasingly sophisticated, delivering everything from live football to bedtime stories.
Give home users faster connections and watching movies on the web might become enjoyable. And once we want to watch movies on the net, someone, somewhere will find a way of getting the bandwidth into our houses to make it possible.
• Jim Giles works on the Wellcome Wing project at the Science Museum in London
