November 1997

BY ANDY THOMAS AND WILLIS CHUN

The merging of high-speed and sophisticated communication techniques with powerful new personal computers has dramatically altered the face of long-distance collaborative computing in recent years. Technology has progressed beyond the days of jerky video conferences resembling Bgrade, out-of-synch foreign films. Sophisticated call management features and new video handling algorithms have made the collaborative computing experience more pleasurable and natural.

UNDERSTANDING COLLABORATION
Before you try to analyze the relative technical merits of multimedia collaborative computing systems, understanding the dynamics of collaboration will help establish the priorities you should use to compare systems. After all, leading edge technology matters little if it is not needed or if it does not add substantively to the collaboration.

As one might expect, video imaging is critical during the early stages of collaboration, but as the process continues, video communication recedes in importance as audio and data applications carry the communication load. For example, when a project team is first formed, team members need to get to know each other and this involves seeing what the others on the team look like. But as team members become comfortable with each other, verbal communication emerges as the most important medium. Video provides secondary visual clues.

Much of the information exchanged during a collaborative meeting will be communicated verbally. Decisions will be reached, responsibilities assigned, and actions taken on the basis of the spoken word. As a result, call management capabilities like directory dialing, call logs, powerful directory management facilities, and visual voice mail processing can have a palpable effect on the productivity of a group. In addition, systems that require the use of headsets or ear slugs often impede audio communication rather than improve productivity.

Once the work of a group has reached a certain point, the amount of information that must be shared often exceeds the effective limits of verbal communication. Data communication becomes critical at this point. Data applications, such as shared spreadsheets, interactive white boards, electronic slide presentations, and high-speed file transfer, facilitate the sharing of large amounts of data.

KEEP YOUR OPTIONS OPEN
Collaborative computing has a way of snowballing. Once an individual or a group begins using it, others soon follow. As use increases, pressure builds to expand the collaborative computing systems or to increase the number of systems available. By implementing systems that conform to industry standards, you are assured the systems you purchase today can be efficiently expanded in the future.

The umbrella industry standard for multimedia conferencing, H.320, was defined in 1990 by the International Telecommunications Union (ITU). In theory, audio and video equipment that is H.320-compliant will function with any other vendor’s H.320 equipment. H.320 defines most of the basic processes involved in multimedia conferencing, such as video compression, decompression and digitization, as well as high-quality audio compression and transmission. Even though an H.320 channel includes a data link for shared data processing applications, H.320 does not establish the protocol used on this data link. For this reason, you can not be assured that data applications on H.320 systems from different vendors will interoperate.

Another ITU standard known as T.120 establishes the data application protocol. When an application is said to be T.120compliant, it can be shared by meeting participants at either end of a two-way multimedia conference or by several groups of participants in a multipoint conference. Many experts believe that T.120 applications will gain popularity because one of the first T.120 applications, NetMeeting from Microsoft, is distributed free of charge. In fact, Microsoft is bundling NetMeeting into its Windows98 PC operating system. NetMeeting was originally developed as a collaboration tool for local-area networks (LANs), but it can also be used for multimedia conferences over the wide-area network (WAN). Microsoft claims that as many as 10 million copies of NetMeeting have already been downloaded from its Web site.

Another ITU conferencing standard, H.323, is visible on the horizon. H.323, which defines how multimedia conferencing will be conducted over the Internet, will have a profound effect on collaborative computing throughout the rest of this century and well into the next. Although H.323 promises to eliminate the complexity of implementing today’s specialized circuits for multimedia conferencing by simply using LAN/WAN connections, most corporate networks today can not support widespread use of H.323 conferencing. This will change of course, but most experts believe H.323 will not be used pervasively until around the year 2000. Until then, traditional circuitswitched connections will still be required.

FLEXIBLE CONNECTIONS
For collaborative computing to be productive, a high-speed communication connection must be established and that means ISDN. How ISDN lines are provisioned today will affect how easily collaborative systems can be expanded in the future. Simply running ISDN lines from a phone company to all the conferencing systems in a facility may seem to be the easiest solution, but this means bypassing the facility’s PBX, if one is present, and hardwiring the ISDN lines to certain locations in the building.

An alternative with greater flexibility involves bringing ISDN lines into the PBX and switching the high-speed links to the conferencing systems. Some PBXs automatically provide ISDNequivalent speeds to the digital telephones they are connected to. In this case, no additional ISDN-specific wiring is needed because every phone line can provide highspeed access for multimedia conferencing systems. Existing or additional PRI trunks between the PBX and the network are also available for other applications when they are not being used for collaborative computing. ISDN lines that are hardwired into conferencing locations, on the other hand, would sit idle when collaborative computing systems are not in use.

GETTING THE MOST OUT OF YOUR SYSTEM
Certainly the growth potential for a multimedia conferencing system is an important consideration, but just as critical is whether the system is powerful enough to provide the functionality you need now. The inherent power of the system’s codec (coder/decoder) will dictate the performance of a system. Many codecs rely on the horsepower of the PC’s CPU and actually assign conferencing tasks to the CPU. Although many CPUs are quite powerful in their own right, burdening them with conferencing tasks will only slow down other PC applications. Anyone who has struggled with an unresponsive network server knows how aggravating a slow application can be.

Video input and output flexibility will also affect a conferencing system’s usefulness. Besides camera inputs, users may want to input images from video cassette tapes or laser discs. In addition, some conferences are more productive when the live video feed is output not to the PC monitor, but to another device such as an external television. This frees the PC monitor for sharing data applications. Some multimedia conferencing systems are capable of outputting an NTSC-composite video signal, which can be switched directly from the PC to an external television.

BUYING THE RIGHT SYSTEM
Comparing multimedia conferencing systems with equivalent capabilities and functionality is more difficult than it may seem. Careful analysis may reveal that capabilities you require are considered system options and aren’t included in the quoted cost. Spending time to specify the functional and operational capabilities of the system will pay off in the long run. Multimedia combined with the Internet has enhanced the productivity of collaborative computing and this, in the end, is what should matter most to business users when making the decision to purchase a conferencing system solution.

Willis Chun and Andy Thomas are part of Symposium Multimedia Conferencing at Nortel. Symposium harnesses today’s sophisticated media into an integrated portfolio of products and services that delivers powerful communications solutions for offices and call centers. Visit the company’s Web site at www.nortelnetworks.com.