Six European telecommunications and eight video-telephony companies have started a nine month project, the European Video-telephony Experiment part two, EVE-2 for short. It will concentrate on the human, social and marketing aspects of video telephony and follows earlier work on getting various phones to work with each other. As is usual with standards, the core video-telephony work provides a number of options, so before EVE-2 could get under way, preliminary work was needed to define a functional profile. For example, it was discovered that some of the videophones took their timing from the network clock, whereas others are timed from the video data stream – both are permitted within the standard, but they are fundamentally incompatible. Likewise, the protocol for dynamic changes in allocation between sound and video was unclear, with some phones having the ability to change a partner’s attempt to shuttle bandwidth between the two channels. Now that the technicalities are more or less worked out, EVE-2 is looking at how people actually use the technology. Graham Seabrook, technology manager with British Telecommunications Plc’s Visual Business Systems, says that trial customers have agreed to keep a call diary until next June, detailing the nature of their calls and any technical problems. On top of that, the companies involved – the Deutsche Bundespost Telekom, France Telecom, PTT Telecom Netherlands, SIP of Italy and Norwegian Telecom – will be logging ISDN lines to pick up call pattern data. Users will be interviewed on a monthly basis and information collected on their circumstances. Some preliminary findings are already coming in. Surprisingly, Seabrook says that call durations actually seem to increase when people use video – partly, he suspects, because it’s more difficult to cut someone short when eyeball to eyeball. EVE-2 is part of a five-year European video-telephony programme that is still being sketched in by the partners. Equipment suppliers include Tandberg Data A/S, Philips Electronics NV, Matra SA, Dornier GmbH, Standard Elektrik Lorenz AG and Aethra SA.
