Getting ready for multimedia

Multimedia conferencing, the telecommunications industry's newest glamour technology, has recently been embraced by industry consultants and vendors alike. Audio conferencing-the grandfather of the conferencing industry and almost as common as the telephone-continues to be the foundation for all conferencing-related solutions.

Videoconferencing, based on a more complex set of variables, developed somewhat independently as a remote meeting solution. Its duration has been riddled with starts and stops, as differing approaches continue to be resolved among vendors and standards bodies. But videoconferencing's steady climb to stardom has proved that it is a viable business solution that meets the demands of today's global meetings (Figure 1).

Before the "discovery" of data conferencing-also referred to as audiographics and document conferencing-barely two years ago, no pressing reason existed for audio and videoconferencing vendors and service providers to jump into the fray together. Only in the last 12 months or so, as data conferencing has come into vogue, has the vision of combining audio, data and videoconferencing been born (Figure 2).

Today, we use the term multimedia conferencing to describe this new and still-evolving blend of technology solutions. Audio conferencing technology is proven and stable, and videoconferencing is well on its way to desktop acceptance. Before audio, video and data conferencing can be integrated, however, a number of challenges must be addressed, including infrastructure, ubiquity and others.

Where is multimedia conferencing today? What challenges are still ahead for data to catch up to the success of audio and videoconferencing? The future of multimedia teleconferencing lies in the answers to these questions.

Why multimedia conferencing? Personal computer users who like audio and videoconferencing will naturally want to conference data as well. Multimedia conferencing combines all three media through a desktop interface. It can best be visualized as two or more people using their computers to collaborate-to see and hear each other while working together on the same computer file.

Widespread penetration of multimedia conferencing depends on several factors aligning simultaneously:

a sufficient broadband network infrastructure to support the video quality expected by users economical cost for both endpoints and for the transmission bandwidth that ties them together compelling user applications ubiquity based on standards compatibility and ease of use Although these elements are being addressed from a variety of angles, they will not realistically converge for several years. Those who try to ramp up at this point in the game can expect to encounter some rough waters.

The search for the Holy Grail of the conferencing industry has always been the same: to find valid business applications that can be supported by an easy-to-use, economical infrastructure. To understand multimedia conferencing, it is best to understand its predecessors and the infrastructure required for each (Table 1).

Users have a tendency to focus on the endpoint cost as the "entry fee" for getting into a particular form of conferencing. Bandwidth, however, dominates the life cycle cost of any form of conferencing. Studies have shown that transmission accounts for more than 90% of a conferencing system's life cycle cost.

Meanwhile, pricing for the desktop endpoint is rapidly declining. In the relentless pursuit of new applications requiring higher-speed chips, Microsoft and Intel will provide conferencing ability for all desktops at the operating system and application level within the next two years. Conferencing capabilities will be built into the Intel MMX chip and into Netmeeting software, which will be bundled with Microsoft's Windows operating system. Essentially, the endpoint price will be free.

The infrastructure shift Transmission is becoming the key to the conferencing question just as the business infrastructure is undergoing a radical shift from a hybrid circuit and packet-switched model to one that is entirely packet-switched-but the full transition is still a few years away.

Currently, all telephony and video connections are on switched circuits. Most early adopters of desktop video are running individual ISDN lines to each host computer, which is extraordinarily expensive. Although ISDN pricing varies by region, the monthly access charges for each endpoint typically run between $20 and $100 a month, while domestic 128 kb/s connections average about $30 an hour.

Using ISDN also creates redundancies. It would be more economical if the user's computer could access videoconferencing applications through the local area network-a packet-switched network to which the user is already attached. Unfortunately, there are several issues that need to be resolved before this concept becomes reality.

First, a suitable video connection requires a minimum of 112 kb/s bandwidth to deliver the absolute minimum acceptable quality demanded by business users. A 384 kb/s connection is preferred.

Although a standard Ethernet LAN provides a 10 Mb/s bandwidth, that bandwidth is shared by all users, and an additional 112 to 384 kb/s may not be available. For multimedia conferencing to be supported by an enterprise network, the organization will have to upgrade its network infrastructure to switched Ethernet, isoEthernet, 100 Mb/s Ethernet or asynchronous transfer mode.

Another concern is that a packet-switched LAN does not guarantee a specific time of arrival for information packets. The packets are sent out by all endpoints when required. If a packet collision occurs, the endpoints resend the information. Unfortunately, an audio or videoconference requires constant information flow to sustain acceptable quality.

Recently, techniques for ensuring low latency-and consequently a guaranteed quality of service-have become available. The most popular of these is RSVP, a network resource reservation protocol in which an individual set of endpoints reserve bandwidth across a network. The implementation of this protocol requires upgrades to all the switches and routers in the network. This can be accomplished rapidly in a private network but will take several years for public networks.

Finally, until all endpoints are on packet-switched networks, a gateway between circuit and packet-switched endpoints will be necessary. Approximately 150,000 legacy group video systems are in use today. Several conferencing product vendors are in the process of designing gateways, although none have been delivered yet.

What do users want? Audio and videoconferencing have caught on more quickly than some technologies because they are a natural extension of the everyday meeting experience. People are accustomed to gathering in a room to see and hear each other. A key question is: How does data integrate into the conferencing experience? Data is completely absent from some meetings, which purely involve discussion. In other instances, data is brought to the meeting in the form of charts or some other type of graphic information. When data is required for audio or videoconferences today, it is sent to participants by fax, e-mail or an overnight delivery service before the meeting begins. Data conferencing provides an easier means for adding the data element, either before or during the conference.

The ability to conference data is governed by a set of standards labeled T.120 by the ITU-T. Interoperability issues have been addressed far in advance of the technology's widespread use, clearing the way for ubiquity and user interoperability-one of the first times that a technology group has addressed these important issues so far in advance.

Some industry consultants believe that the addition of data is appropriate for group presentations and deep collaborative project work. "Deep" in this context refers to the need to work on individual words, cells or graphical elements, as opposed to summary-level discussion.

The most compelling version of this concept is in the support of software help desks. Much of the difficulty of resolving software problems centers around getting the two involved parties to communicate. The user employs simple, non-technical terms to describe how he or she sees the problem, while the help desk staff uses "computerspeak."

If the help desk staff could directly view what the user is experiencing, look at the software configuration and even transfer files in real time to adjust it, the efficiency of the help desk process would be vastly improved. Given the amount of resources spent by both vendors and corporations on help desk support, this would be a major breakthrough.

Multimedia conferencing will also likely be critical for distance learning applications in which the instructor uses real-time communication and different forms of media to maximize the retention of knowledge. As the American economy shifts toward a knowledge-based service focus and more workers telecommute, this application seems particularly attractive.

Ubiquity Technology truly becomes ubiquitous when it is transparent to the user. Good examples are the motors and transistors used in hairdryers and many other everyday appliances. Engineers have ensured that consumers don't need to know anything about the technology to experience its benefits-in this case, dry hair. Audio conferencing is close to being ubiquitous right now-although videoconferencing and certainly multimedia conferencing are still pretty far off.

The question of ubiquity is directly related to the interoperability standards that underpin the technology. When fax machines first hit the market, each had its own proprietary language and could only speak to another of the same lineage. Because of industry consolidation around internationally sanctioned Group 3 and 4 fax standards, users don't have to concern themselves with the brand of fax machine to which they are transmitting. Similarly, because telephony standards have been in place for such a long time, users of audio conferencing don't have to worry whether their telephones are compatible.

The standards for videoconferencing and data conferencing, however, are relatively new. Most of the T.120 data conferencing standard was ratified in late 1995.

Although the H.320 videoconferencing standard was ratified in late 1991, it has taken more than four years for the videoconferencing industry to implement it with a modicum of success. Most large users continued to use tried-and-true proprietary algorithms because they knew they worked.

Ubiquity is also directly related to ease of use. When you pick up a hairdryer, you only have a few options to select from, any one of which is pretty simple to understand. Users of videoconferencing, however, are still required to understand video and audio compression algorithms and, to some degree, data rates.

T.120, the data conferencing standard, has a leg up because it could learn from the mistakes of H.320 and because it was largely driven by the efforts of one company. Databeam has been the chief architect behind the standard, licensing its implementation toolkit to the majority of industry players. Nonetheless, if history is a guide, there will be compatibility issues for at least a few years that will limit the penetration rate of this technology.

Also, before multimedia conferencing becomes widespread, icons must be easily understood, technology variables must be limited or addressed transparently, and multipoint service issues must be resolved.

Studies show that participants gravitate toward multipoint meetings as they become comfortable with a conferencing technology. They simply want to include the right people-who may be located in more than two places-in the meeting. At this point, however, multipoint multimedia conferencing cannot be conducted in an automated manner because of the server technology's current limitations. Users will expect a PC-based conference to work like a regular phone call, meaning that it should be called up on demand and have no pre-established duration.

Carrier concerns Realistically, multimedia conferencing will take several years to reach the success that has already been ascribed to it. We are currently in the "hard engineering" stage in which solutions are not very elegant or economical.

Carriers with the task of providing users with an immediate multimedia conferencing solution will want to focus on two critical infrastructure elements: creating sufficient bandwidth between users so that connection reliability and video quality are acceptable, and supporting a dependable help desk to which users can turn when they encounter difficulties.

Customers will have plenty of other concerns that will have to be addressed. Don't let them stub their toes out of the starting gate over issues that can easily be solved with sufficient bandwidth.

Art Zeile is Vice President of Marketing at LINK-VTC Inc., Boulder, Colo.