Technology Showcase: Videoconferencing Systems

Feb 1, 2004 12:00 PM, By Nick Dager

For the longest time, videoconferencing was one of those “next-year” technologies. Although the concept has been in at least limited application for more than two decades, videoconferencing never quite became a mainstream business tool. The available technologies were seen by many to be too cumbersome or too expensive, and in addition to that, most businesspeople believed in the power of face-to-face meetings. All of that was coupled with the fact that domestic and even international travel was relatively easy and affordable for most companies. “Next year” was always going to be the year that videoconferencing would really catch hold in the market.

Today videoconferencing is experiencing more widespread use than ever before, and there are several factors to explain why that is so. One, unfortunately, has been the aftermath of 9/11 and the subsequent economic downturn. With travel dramatically restricted and company budgets slashed, businesses increasingly turned to various kinds of videoconferencing not as a luxury but as a necessity.

But technology improvements have contributed to the success, as well. There is a wide range of videoconferencing systems, but all of them are based on the same basic concepts. Display devices and cameras are linked to various remote locations through phone lines or, increasingly, the Internet. There are many variations on this theme, and systems are evolving to serve different applications. Some videoconferences involve major meetings and require larger display screens with superior visual quality. Other more routine meetings rely on Internet-based systems that can deliver a videoconference right to the desktop.

Even in the best of times, videoconferencing can offer many benefits to businesses, government agencies, schools, and other large organizations, especially those with offices that are spread across a country or across the world.

The most obvious benefit is the reduction of travel costs, but there are others. Videoconferencing has the potential to speed up the decision-making process, and it can help keep meetings shorter and more focused than face-to-face meetings. Top management can use it to reach employees who are scattered all over the world at the same time. Videoconferencing can be invaluable in delivering training to far-flung personnel without requiring them to travel to a central location.

One often overlooked potential benefit is the ability to use videoconferencing to share key documents or images in real time. Design teams can brainstorm while everyone is looking at the same drawing. When time might mean the difference between life and death, doctors can consult while studying the same x-ray. Expert witnesses can appear in a courtroom without having to travel. Students in extreme rural areas can interact with a campus miles, even entire states, away.

THE BASICS

There are three basic kinds of videoconferencing systems: desktop, set-top, and integrated.

Desktop videoconferencing systems bring video communications into a worker's office. They are capable of delivering full-motion video directly from a standard PC. Currently, there are desktop systems from a variety of manufacturers that can deliver high-quality images and sound at a reasonable cost. These systems provide H.323 standard voice and video, as well as the ability to share applications such as documents, charts, and graphs.

Set-top videoconferencing systems are more complete and get their name from the fact that they're designed to sit on top of a video monitor. They are particularly useful in smaller conference rooms or in any other venue where small work groups are gathered to meet. Generally, set-top systems are portable enough to fit on a cart so that they can be moved from room to room for shared use. Set-tops tend to have better video quality than desktop systems, and they also tend to work better with auxiliary equipment, including devices such as document cameras.

Integrated systems are the largest videoconferencing systems. They are most often employed in large conference rooms or classrooms that can accommodate a large number of participants. An integrated system typically involves a centralized location for the wiring and processors that control the operations. Equipment in the main conference room usually includes the principal camera, displays, and peripheral video sources. Integrated systems are typically customized configurations and are equipped with features that allow for the room to be used for other functions in addition to videoconferencing. Most integrated systems available today are capable of connecting to both H.320 (ISDN lines) and H.323 (IP/LAN).

H.320 and H.323 are among the global technical standards for videoconferencing that have been defined by the International Telecommunications Union. As standards they are accepted everywhere.

The basic technical standard is H.320, which is actually the suite of standards that defines videoconferencing interoperability over ISDN lines. These standards define rules for establishing communications, framing and synchronizing media, and inverse-multiplexing ISDN channels.

H.320 includes other video and audio coding standards. H.261 is a video compression standard for bandwidth multiples of 64 Kbps. G.711 is the basic audio compression at 48 Kbps to 64 Kbps. G.722 is higher-quality audio at those same bandwidths. G.728 is an audio compression standard for lower bit rates (16 Kbps).

H.323 is the suite of standards defining interoperability of videoconferencing over packet-switched networks with no guaranteed quality of service (QoS). These standards define the packetization and synchronization of media over non-QoS packet networks and define a gateway for the interoperability of H.320 and H.323 systems.

H.323 also includes the following video and audio coding standards. H.261 is the same video compression standard used in H.320 and H.323. G.711, G.722, and G.728 are audio compression standards also used in H.320. G.723 is the audio compression standard for 5.3 Kbps and 6.5 Kbps.

H.324 is the suite of standards defining videoconferencing interoperability over POTS (plain old telephone system) that establishes low-bandwidth multiplexing and control protocols. Although H.261 is included in the standard, H.263 is commonly used because it can compress video for transmission at low bit rates. H.324 incorporates only the low-bit-rate audio compression, G.723. In addition, V.80 is the standard application interface for developing H.324 systems that convert synchronous data streams to modem asynch, enable rate adjustments during a call, and notify client software of lost packets.

T.120 is the suite of videoconferencing data collaboration standards that is included in the three H.32x standards described previously. T.120 includes T.124, a conference control standard; T.126, a standard for sharing still images; and T.127, a binary file transfer standard.

Some new videoconferencing systems coming to market this year are based on the H.264 standard, which incorporates MPEG-4 compression for higher-quality video images.

CHOOSING A SYSTEM

Selecting the right videoconferencing for your application really boils down to the way you answer a few basic questions. The first is, how does your company want to use such a system? Put another way, what do you want to accomplish with videoconferencing? How many offices or locations will need to be connected? How many people will take part in videoconferences at each location? Will each location have the same equipment, or will headquarters have a higher-quality system than will regional outlets? Will you be using that for conversations only, or will charts, graphs, and other documents need to be displayed, as well? Where will the system reside in your facility? Will it be in an existing room, or will you need to build a room dedicated for this purpose?

In addition, how will the system be connected? Will it be through existing or new phone lines? Cable modem? The Internet? Will this be a dedicated line, or will it have other uses?

Once you know the answer to those basic questions, you'll be ready to speak with manufacturers to determine the right videoconferencing system for your application. Here are a few examples.

MANUFACTURER RESOURCES

Aethra's set-top Vega StarGold's integrated multipoint conferencing unit connects as many as seven sites in mixed mode (ISDN and IP) with dial-out and dial-in (Meet Me) configuration. The Continuous Presence feature lets participants at all sites view one another simultaneously. Several versions are available for connections up to 768 Kbps over ISDN BRI and 2 Mbps over IP, as well as connections up to 2 Mbps over ISDN PRI and IP or over leased lines (X21, V35, RS449, G703). XGA input and output ports provide PC plug-in or LAN connection for simultaneous dual-stream video and live PC presentations with enhanced images. Voice Tracking technology enables the camera to automatically track and frame the person who is speaking.

ClearOne recently discontinued its domestic A/V integration services but introduced its full suite of Let's Conference services this year. ClearOne's set-top models, designed to be easy to use, feature built-in Web browsing and application-conversion tools to enhance presentation capabilities. The V-There line of videoconferencing systems allows Web browsing and the sharing of audio and video over LAN or ISDN at rates of up to 364 Kbps.

Compunetix manufactures and supports a complete family of H.320 standards-based Multimedia Multipoint Control Units. Its products, including the Orchestrator and the Virtuoso Hybrid, are modular and range from 8-port systems to 160-port systems.

Conferserv is an H.32x-compliant platform or bridge that enables the recording and streaming of H.32x meetings, presentations, and Webcasts. It is designed to work with industry-standard videoconferencing systems such as Tandberg and Polycom. The platform is built on Microsoft .NET and other leading industry standards to ensure a robust and secure operating environment.

D-Link offers the patent-pending D-Link DVC-1000 i2eye videophone as a standalone device that does not require a computer to videoconference over the Internet. A standard telephone and television plug in to a broadband Internet connection through the DVC-1000. Using compression technology, the system can send and receive video at up to 30 frames per second. The manufacturer calls it an “ideal solution for consumers and small businesses with high-speed Internet access.” Calls are received or initiated using a built-in remote control. There is also built-in caller ID for added privacy protection.

Motion Media's mm745 IP videophone is another telephone-based system with an integrated Web browser. Ordinary telephones operate using a 3.5 kHz bandwidth. By comparison the mm745 makes use of 7 kHz for increased clarity. The mm745 uses the Equator processor. Touch-screen control has been developed as an option. The mm745 is designed to be compatible with other H.323-based videoconferencing equipment, multipoint conferencing systems, and network hardware such as gateways and gatekeepers.

Polycom makes a wide range of videoconferencing systems. The VSX 7000 comes with a trademarked feature called the Siren 14Plus, which includes an integrated speaker and subwoofer for improved audio. The VSX 7000 is an integrated part of Polycom's Office product and supports Polycom's Global Management System, PathNavigator, MGC conferencing bridges, and IP phones.

Scotty manufactures the Scotty Mobile. It features an industrial PC as its platform, a high-speed data transfer system, digital video recording, as well as traditional H.320/H.323 videoconferencing and data conferencing. It runs through satellite phone, VSAT, ISDN, IMUX, or leased line. DC power supply, multiple network interfacing, high-resolution camera, speaker, microphone, and echo cancellation are all built-in. No extra adapters are needed. The Scotty switching matrix manages numerous inputs and outputs for external audio and video.

Sewam Holdings' iCam UC350 features a multifunctional pan/tilt Web camera that works on an IP network. An autotracking system allows it to be controlled remotely by a Web-site visitor. The iCam UC350 is bundled with software programs such as iMeeting, iWeb, M-Meeting, and iGame and can deliver functions such as video chatting, IP phone, IP videophone, video monitoring, Web broadcasting, multimedia office, and multimedia gaming without additional cost.

Sony has added its Memory Stick technology to videoconferencing. The PCS-1600 system features a built-in Memory Stick port to share images and incorporate multimedia live into meetings. Color-coded cabling expedites setup. Once the PCS-1600 unit is plugged in to a network interface, the system configures itself automatically. The optional Smart Management Solutions software provides organizations with centralized scheduling, systems management, and address-book control through any PC connected to the company's LAN/WAN. The PCS-1600 has a built-in ISDN port as well as a 10/100Base-T port for LAN/WAN connectivity.

Tandberg offers multiple videoconferencing systems, including the 2500 and the 8000. The 2500 has one or two monitors, a roll-about stand, a camera, remote control, a microphone, as well as integrated cabling. The 8000 includes includes two monitors, a stand, a camera, remote control, a tracker, a microphone, and integrated cabling. The key differences between the two is the size of the monitors and the relative image quality. The 2500 comes with one or two 27/29-inch monitors; the 8000 has two 50-inch, 16:9 plasma screens. Both can support multiple networks such as ISDN BRI, IP (LAN), X.21, or V.35.

Vcon has a wide range of videoconferencing products. The MediaConnect 9000 work-group videoconferencing systems can be used as large-screen multimedia devices even when not being used for videoconferencing. It is available in an integrator's configuration or as a full roll-about model that includes cart and monitor. Dual-monitor and triple-monitor systems are also available for large conference rooms, training facilities, or classrooms. All systems are dual-mode (H.320/H.323) and use a VGA monitor. The MediaConnect 9000 includes VoiceFinder, a voice-activated camera tracking system, as an option.

VTEL's Vista Pro includes the company's videoconferencing codec, an integrated Windows PC, a pan/tilt/zoom video camera, an omnidirectional microphone, and a wireless handheld remote control unit. It carries a 36-month factory warranty that covers hardware and VTEL software.

Please gather as much information as possible about the videoconferencing systems that meet your needs. From there a good place to start is a visit to the Web site of any of these videoconferencing systems manufacturers.

Nick Dager is the editor and publisher of Digital Cinema Report, an online news service about wide-screen production and presentation. He can be reached at nickdager@digitalcinemareport.com.