Unfortunately, the focus on compression and efficiency has seen human requirements and interface developments somewhat neglected. Whilst standard TV cameras and screens with poor acoustics are often fit for purpose, the reality is, for many users they can be very lacking. From an engineering viewpoint, it is easy to become intoxicated by the advances made in compression technology and the detailed phenomena relating to displays. However, for the user, these issues are distracting and limit effective communication.

Existing video conferencing systems present images of humans of the wrong size and colour, that become blurred and jerky with movement. They lack good synchronisation between speech and lip movement, have a voice that does not emanate from the mouth, but from some box, do not permit eye contact or body language and do not create the illusion of "being there". This is compounded by the need for more than one screen and the lack of any shared workspace. Also, everyone appears to stare over each other's heads. All of this adds up to an unnatural and somewhat sterile workplace which is difficult to become acclimatised to if all those in a communications session have not been previously acquainted in real life.

The video telephone has even more problems with drastic signal compression, very small picture size and gross distortion in all respects. What is not clear is what the users will put up with. Perhaps it is not unreasonable to suppose that they may expect to see at least a 'living room standard' TV presentation.

Watching human interactivity in a real conference room reveals a few seemingly imperative requirements to maximise the usefulness and chances of success of any tele-meeting. Mimicking such environments as closely as possible to provide a facsimile - a virtual conference room, with humanised interfaces and workspace might just work.

Presenting people in full size on a distortion free, high definition daylight bright screen, with electronically steerable microphones that focus the acoustics on any one speaker so their voice emanates from their image seems essential for realism. Mounting cameras behind the display screens to achieve the illusion of eye contact, a shared workspace - whiteboard and desk top - for all users to interact with also gets us closer to reality. For those with a paper fetish an instant fax can be realised at only 240kbit/s.

Attaining the objective of feeling that ?you are there? - teleported to a new location with humanistic interfaces and facilities has to be a primary objective. For beyond telecommunications there is a need for: a global reduction in physical transport and travel; a more efficient and reduced use of raw materials and energy; and more productive and less stressful lifestyles. All of this is now possible by the removal of the capacity bottleneck inflicted by copper cable and radio systems, which have been outmoded by optical fibre. For the most part all of the other technologies required are available or coming to fruition. Probably the most demanding requirement is the change of mind set required - telecommute with a speck of oil instead using gallons to travel.

Peter Cochrane holds the Collier Chair for the Public Understanding of Science & Technology at the University of Bristol. His home page is:
http://cochrane.org.uk