by A.B. Covell  Designing a Videoconferencing Solution Videoconference System Alternatives A review of the various system alternatives, the focus of this section, will help you to get a handle on the videoconference functionality and quality you can achieve at various price points. It will also stimulate you to begin to craft some preliminary deployment ideas, which may incorporate systems from more than one of the categories described here. Room System A well-done room system offers the highest quality available, but at the highest cost as well. A room system implies a room with specially designed lighting and acoustic characteristics designed for even, clear audio and video capture. Multiple cameras and microphones are mounted with a technician controlling the active video source and mixing the audio, ensuring that everyone in the room can be seen and heard clearly. The technician may be housed in an a djacent soundproofed control room with a glass panel that enables the technician to keep an eye on the activity in the videoconference room. Supplementary video inputs, such as a document camera and computer with T.120-compliant data/applications sharing software, complement the standard talking-head video feeds. Multiple display devices enable room system participants to simultaneously view various inputs from the remote site. Many of the technical components of the room system (e.g., cameras, microphones, mixers, etc.) are the same as those used in a regular video production studio, and these items are purchased through standard media industry channels. The networking and telecommunications gear and codec provide the videoconference connectivity capability, and are purchased from specialized videoconference vendors and telecom companies. Room systems are sometimes equipped for satellite transmission, though most systems rely on dedicated leased WAN services or switched ISDN connections. The cost of room systems can easily run into the hundreds of thousands of dollars. In addition to the start-up cost to construct and equip the room, there is an ongoing cost to staff the facility during videoconference sessions. Many large corporations have been able to justify the significant expenditure for such high quality, dedicated facilities by virtue of the savings on travel and the increased windows for effective communication that can occur among high-level corporate decision-makers. Rollabout The rollabout is a midrange system for individuals and small groups. The rollabout bundles a codec, camera, monitor and microphone on a cart with wheels that can be easily rolled from room to room. A wireless remote-control unit, touchpad, or keyboard lets a single system operator place a video call, then control the camera position, speaker volume and video source. The controls are designed with ease of use in mind so that a trained technician is often unnecessary -- for most rollabouts a videoconference participant with a minimal technology comfort level can operate the equipment. The quality of the rollabout system can't match the quality achievable with a room systems, given the acoustic treatments, multiple cameras and high-quality components, but a rollabout running H.320 384-Kbps ISDN can provide more than 20 frames-per-second video at full CIF (full screen on a standard U.S. video monitor), with high fidelity audio. The resulting quality is fairly impressive. The rollabout solution not only offers good quality videoconferencing, it also ensures a useful degree of flexibility. Given that the unit is on wheels, it can easily be moved about and be plugged into WAN ports (e.g., bridged ISDN circuits), turning your conference rooms into videoconference ready meeting rooms, at minimal cost. Rollabout system prices are in the $20,000 to $60,000 range and are available from videoconference vendors such as PictureTel, VTel and CLI. Lower-end systems will still offer the basic technology but lack features that extend functionality such as dual monitor capabilities, the ability to include voice calls in a conference, voice-activated camera positioning, and high-resolution graphics displays. The quality and functionality of rollabout systems has increased over the past few years, as prices have fallen, making them a popular choice for many organizations with a sufficient need for in-house videoconference facilities. If your users will demand higher-quality video and audio, but you want to retain a degree of flexibility, the rollabout may be a good choice. Desktop Videoconferencing Desktop systems now come in various flavors, including low-bandwidth Internet and POTS systems and higher-quality ISDN and LAN/intranet systems. Each is built on the same basic model -- that of a compact camera and single microphone that capture the sights and sounds of your desktop and the desktop you wish to interact with, and transmit that through the network to enable individual int eraction, desktop to desktop. Desktop systems also routinely provide whiteboard, document sharing and applications-sharing features, making them very productive tools for professional collaboration that overcome geographic barriers. Until recently, these tools had been offered as proprietary extensions, but with the new T.120 suite of standards, vendors are now building interoperable collaboration tools into their products, significantly extending the functionality of desktop videoconference systems. POTS-based systems, like VDONet's VDOPhone, are usually very inexpensive. Video and audio compression usually occurs in software, keeping hardware costs down. The bandwidth constraints of today's 33.6-Kbps modems requires compression that produces relatively poor quality video and audio, which is substandard for most business applications. Still, the ubiquity of the POTS network and the low cost of POTS videoconference solutions make this the videoconference option with the greatest potential when it comes to universal deployment, especially in rural locations. If you think POTS videoconferencing is in your future, make sure you select H.324-compliant software and modems that adhere to the new V.80 standard for synchronous data flow over asynchronous modems. Videoconferencing systems running over ISDN, like Intel's Proshare Conferencing System 200 and the PictureTel Live 200 , take advantage of the bandwidth guarantee of the circuit-switched ISDN network to delivery higher-quality video and audio. With hardware video capture and compression, better-quality camera, ISDN NT-1 and adapter card, and ISDN circuit, the ISDN desktop solution costs much more than the POTS or Internet solutions, usually running from $1,000 to $2,000. The typical ISDN desktop system uses two bonded ISDN channels at 128 Kbps and complies with H.320 and T.120 standards, providing a solution that offers excellent flexibility when it comes to connecting with other videoconference desktops both in and out of the enterprise. With decent quality, reliable video and audio, and good data and applications-sharing tools, the ISDN solution is especially well-suited when business professionals need to routinely collaborate on projects from remote locations. The LAN and intranet videoconference solution typically uses capture and compression hardware similar to that bundled with ISDN solutions, but is configured to run over a packet-based transport. For example, Intel Proshare Conferencing System 200 can run over IPX or TCP/IP packets, as can the PictureTel LiveLAN product. The LAN/intranet solution can save money on unnecessary ISDN connections if the videoconference users share the same network infrastructure. Of course, the flexibility to interact with outside parties is eliminated, and the LAN/intranet network manager must manage usage to avoid situations where videoconferences conflict with applications that consume network resources. Internet videoconferencing systems, like White Pine's Enhanced CU-SeeMe and Microsoft's NetMeeting, provide a low-cost Internet alternative to POTS videoconferencing. Here again, the emphasis is on low cost with inexpensive capture technology and compression technology, resulting in low-quality audio and video. The standard problem of synchronous delivery of decent quality audio and video is compounded since the Internet is a packet switching "best-effort" transport (For more on this see Network Considerations in the next section). The Internet solution, while currently somewhat limited due to bandwidth realities, has incredible potential for future growth given the pervasiveness of the Internet. Sales and customer-service applications, educational uses and a bevy of other applications will undoubtedly flourish once Internet videoconferencing becomes a more viable tool. Now that we've described some general categories of videoconference systems to give you a feel of what's available at the various price points and in differing network environments, we've got to w arn you that the lines among these categories are blurring. For example, PicturePhone Direct now bundles a desktop ISDN system with a large monitor and a third-party echo cancellation product on a rollabout card, and sells it as a poor man's rollabout. Enhanced CU-SeeMe, a low-end Internet product, can be deployed at higher frame rates across an intranet and provide competition for the likes of Intel Proshare. PictureTel is now offering SwiftSite, a low-cost ISDN rollabout that offers ease of use with somewhat lower-quality audio and video than what we've come to expect in a rollabout system. Expect further blurring as the technology evolves and products arrive with enhanced quality and reliability at reduced cost. Designing a Videoconferencing Solution Typical Videoconferencing Applications Characteristics Of A Successful Videoconference Solution Summary of ITU Videoconferencing Standards Videoconference System Alternatives Network Considerations Mix and Match Sample Scenarios Putting It All Together Videoconferencing Web Resources Print This Page E-mail this URL