The last piece of the convergence jigsaw doesn't want to fit into place...It's common these days to hear about converged voice and data networks but adding video to the mix is a trickier proposition. But that may not just be because of the required technology, writes Ben King. High-tech crystal ball gazers have been making fools of themselves for decades, predicting a massive rise in videoconferencing usage that stubbornly refuses to happen. The chief reason for this on-going non-boom has been the sheer difficulty and cost of getting videoconferencing to work. But this could be about to change. Until recently, most video meetings have taken place in special booths, (or 'suites', for those who feel grand). They need expensive equipment, which takes up expensive space, and has to be booked in advance. They generally need a dedicated ISDN line, which can be very expensive, and a patient technician on each end to set the call up. Alright, maybe videoconferencing is easier than getting into a plane and meeting someone - but only just in many cases, and you don't have duty free booze to dull the pain. Part of the problem is that video is an extremely greedy technology in terms of the network resources it uses - not just in terms of the bandwidth required but also the delay between a signal being sent and reaching its target - known in the trade as 'latency'. "A 400 milliseconds round trip is as good as live," says video communications analyst Christine Perey, president of Perey Research and Consulting. "It's essential to user adoption that latency is not too high." Networks capable of this level of performance are expensive and difficult to create. However, the coming of a new generation of IP-based enterprise networks has sent another generation of seers probing the entrails of the sacrificial technology goat and daring to make the call that landed so much egg on their predecessors' faces - that video may be a technology whose time has come. This time round, everything is meant to be different. Video will be delivered to the desktop. Video calls between conference booths will still be possible, as will calls from conference booth to desktop, or to home offices, even mobile phones. Calls will be set up conveniently and easily, by gently clicking buttons built into other common communications applications such as Outlook or Lotus SameTime or instant messenger offerings applications. These apps will know when the other parties are available and what the IP address of their machine is, so there's no need for a technician. They'll also integrate with other communications tools. So if you're talking to someone on the phone and you want to see what they are wearing, press a button and you can switch on a video screen on your phone, or switch seamlessly to your webcam-equipped PC. Video will not just be about conferencing. Training videos, inspiring messages from the CEO, customer interactions, perhaps even news will be delivered over video to the desktop. By 2006, Gartner predicts that 70 per cent of Global 2000 companies will have installed video to the desktop. Any reasonable desktop PCs can be made video ready with the addition of a simple £20 webcam. Video-capable phones are already on the market, though in relatively small numbers, and still at a prohibitively high price. To date, the stumbling block to making desktop video possible is network capacity - which is where converged IP networks come into their own. Video has been offered as one of the applications that will help to drive the next generation of networks. They do the job of today's data and telephone systems through a single network, all running on internet protocol, or IP. In today's cash-strapped times these 'converged' networks have largely been marketed as a cost saving opportunity. Why build one network when you can build two? They also offer a range of other features which tie in with contemporary IT trends, such as hotdesking. An IP-based telephony network can automatically route a call to whichever desk you're sitting at that day or to your home phone or your mobile. Video seems like a rather frivolous option compared to these solid business-like features which ring to the only tune that accountants want to hear - saving money. There are savings to be had from video conferencing but they come out of a range of different budgets, such as travel or training, so it's often difficult to consolidate them and present them as a convincing business case. For some companies video may be the reason they decide to launch a major upgrade or switch to IP. "Video over IP will be the app that comes first," says Steve Cramoysan, principal analyst at Gartner. "Companies don't have video yet - voice over IP is competing with an existing technology that already works well." For others, however, video comes about as an afterthought. Take a company that has installed a high-bandwidth company network or a VPN connecting different sites across the country or across the world. It has been specified to a very high level - to deliver, say, a one second refresh on a CRM application. With little or no extra investment in hardware, the network will be able to run video. A quality of service (QoS) system manages the network to get the different applications required. Low-priority traffic like email can be slowed down to give applications like video the bandwidth they need. The network doesn't have to be converged. "You can still run the phones off a traditional TDM network," says Clive Sawkins VP UK and Ireland at Avaya, a major supplier of converged network equipment. "But you only get the economic and performance benefits running a fully converged network with a gigabit backbone and QoS." When video apps can be deployed relatively cheaply, companies will be able to experiment with more freedom over how they use them, which employees use them and where. Paul Butcher, Mitel Networks COO, feels that for the moment the enterprise may not be ready for video to the desktop. He says: "A lot of people work in open plan offices. They're not very private. So we're still targeting the conference suite for the moment. Executives and sales people are the ones who really need to see their customers and that's where it's really selling at the moment." IP seems sure to displace the old ISDN conference booth sooner rather than later. It remains to be seen whether every office desk will have a webcam and videoconferencing will become as normal as making a phone call. If it does then the UK's pub landlords had better watch out. Someone will need to write a program that makes you look fresh as a daisy after a night on the tiles. For some things, voice will always have the edge.