Past Issues of Government Technology

Videoconferencing Status a Moving Picture

Videoconferencing technology is evolving rapidly, providing new avenues of communication.

by / June 30, 1995 0
July 1995

Vendors: VTEL, VideoServer, ITU, ProShare, Dolch Computer Systems, DSVD, Multitech, DataBeam Corp., Farsite, PictureTel, AT&T;, DataPoint Corp., ViewPoint Systems, VIVO, Hitachi, JVC, Sanyo, Sharp, Creative Labs, Alpha, Altec Lansing, Intel, Personal Technology Research, Microsoft, IBM, Compression Labs, VTEL, Target Technologies

By Alan Freedman

Contributing Editor

Videoconferencing offers the next obvious step in communications, which is "almost" being there. That is, being there enough to accomplish a lot of things you can't do over the plain 'ole telephone system, affectionately known as "POTS." Being there enough to see the body language that speaks louder than words. Being there enough to collectively collaborate on a design. Being there enough to examine a patient and consult with a specialist in the big city.

Video allows criminal suspects to be arraigned while they're lounging in the local hoosegow. In education, holding classes by video with a remote instructor saves time and money.

The applications for learning and technical collaboration are endless. An interesting byproduct of videoconferencing is that group meetings are speeded up, because people have a different attitude when they are "on camera." They come better prepared in the first place, and they're more attentive. Speeding up endless meetings that drone on forever is an automatic productivity boost.

Videoconferencing is going to reduce the costs of business travel, and will allow for some real honest-to-goodness telecommuting. Bosses feel much more comfortable seeing their telecommuting employees than just talking to them.

Waltham, Mass.-based Personal Technology Research, a market research and consulting firm which tracks this business, estimates that shipments of PC and UNIX-based desktop videoconferencing systems - virtually a handful in 1994 - will grow to over five million units in 1999.

Why such explosive growth? Several things are intersecting. First of all, products have reached a certain level of maturity. Although LAN and POTS-based systems are relatively new, WAN-based systems are now in their second or third generation. Prices for WAN-based desktop systems - formerly ranging from $6,000 to $10,000 - have dropped to as low as $2,500 per seat, not including phone lines.

Secondly, ISDN service is finally becoming widespread, and costs have dropped to as little as $17 a month more than a standard business line. It only took the telephone companies a decade to get this vitally-needed service going. Thirdly, Intel has capitulated. Intel was trying to set its own standard for videoconferencing, called PCS, but the international ITU H.320 standard is simply too open and appealing. Intel has announced its ProShare video products will be H.320 compliant.

Lastly, LAN-based videoconferencing is emerging and gaining a lot of attention. Prices - from about $2,000 to $3,000 per seat - are appealing. POTS-based systems are also emerging for as little as $800.

Videoconferencing-equipped PCs will become available by the end of this year. Expect to see portables from Toshiba and others by the end of 1995 or early 1996, and if you can't wait, you can have one right now. Dolch Computer Systems of Fremont, Calif., makers of high-end ruggedized portables, already offers a video-equipped road machine. Both Microsoft and IBM are building in data collaboration and most likely other videoconferencing capabilities into Windows and OS/2 for release some time in 1996.

The First Major Standard

The International Telecommunications Union (ITU) H.320 standard defines the international protocol for videoconferencing, which includes the communications handshaking and the compression algorithm used to squeeze the digitized audio and video into an economical bandwidth. Before H.320, all videoconferencing systems were proprietary, and most of the installed systems today still are.

All current videoconferencing systems are being built with the H.320 protocol. It wasn't until early 1994 that the bugs were worked out and systems were actually talking to each other. By the way, H.320 does not define video quality. Pre- and post-processing techniques plus the quality of the camera contribute to visual quality. Many vendors still feel their proprietary protocol is better than H.320 and of course continue to include it to talk to their installed base.

Data Collaboration

Data collaboration means working on the same data together although in different locations. The first method is the whiteboard - the electronic equivalent of the old fashioned blackboard.

Whiteboard capability lets users interactively draw and annotate anything from complex equations to the design of a new product. A whiteboard is similar to a paint program but with rather elementary tools to draw and erase lines. Some whiteboards allow for simultaneous interaction, others turn the cursor inactive for all but the party drawing at the moment.

Whiteboarding also lets you work on your own data together. It's done by cutting and pasting a window of data into the whiteboard, which can be viewed and marked up by conference participants.

The second data collaboration method is called application sharing, and it provides direct interactive document collaboration. It works like a remote control program, which lets two users each at their respective machines work on the same document, spreadsheet or database simultaneously, although the application is loaded in only one machine. For a number of years, remote control programs have been used very effectively for remote tech support and training.

But we're in the early stages. Many application sharing technologies only provide application viewing. Conferees can view a document being changed and highlight parts of it, but only the user with the application can interact with the software. If you need mutual drawing capabilities for example, look for true application sharing.

In reality, neither whiteboarding or application sharing require a video window. Audio is usually sufficient. For example, U.S. Robotics is bundling Intel's ProShare data collaboration software with its new Digital SVD (simultaneous voice and data) modems (DSVD). DSVD and other types of SVD modems are now arriving on the scene.


The ITU is completing the T.120 standard, which is the specification for data collaboration. The standard provides interoperability of whiteboarding and application-sharing applications, all of which are expected to be T.120 compliant by 1996. Lexington, Ky.-based DataBeam Corp. is the leader in T.120-compliant data collaboration software. It sells its own Farsite whiteboarding and file transfer system and licenses its T.120 communications stacks to all the other vendors, including Microsoft, which plans on building in data conferencing pieces in future versions of its applications in operating systems.

Room and Desktop

Room - or group - system videoconferencing is where it all started. San Jose, Calif.-based Compression Labs (CLI) pioneered digitized video for in-house videoconferencing back in 1982 and is still the leader in large full-motion video room systems running at 384 Kbps and higher. Today, PictureTel, CLI and VTEL all make room systems, with PictureTel having captured more market share, especially with smaller systems running at 128 to 384 Kbps.

Room systems are designed to work with a group of people sitting at a conference table. Group meetings, board meetings and distance learning lend themselves to this type of conferencing.

What's stirring everyone's imagination these days, however, is desktop conferencing. It's one thing to schedule a group conference, it's another to dial up a co-worker and collaborate on-the-fly when the need arises. The desktop also provides single remote users the ability to join into a room system conference.

Point-to-Point and Multipoint

Video communications work two ways: point-to-point and multipoint. Point-to-point is simple. You dial up the person via WAN (ISDN, switched digital, T1, etc.), LAN or POTS - only now you make sure your clothes are color-coordinated lest you appear like a ragamuffin.

Multipoint systems allow three or more room or desktop systems to videoconference with each other. It's this kind of group collaboration that will build the virtual office of the 21st century. But, multipoint is more complicated than point-to-point. WAN-based systems need a multipoint control unit (MCU), which functions like a central switch, or PBX, and joins the lines together.

The MCU also manages the video. It can be set up to switch automatically from one participant to another. It can be manually directed to a particular party, or it can automatically switch the video depending on who's speaking. Lexington, Mass.-based VideoServer Inc. is the preeminent manufacturer of MCUs and OEMs them to major vendors as well as the telephone companies.

If it's too complicated to set up an in-house MCU, call your friendly long distance carrier. AT&T;'s WorldWorx service is a nationwide network that allows H.320 compliant systems to hook up via ISDN lines and have a multipoint conference with up to 24 other conferees. This is the glue needed to make desktop videoconferencing widespread, and should be available this summer. WorldWorx - initially only ISDN compliant - may provide POTS capability by the end of the year after the H.324 standard is completed. H.324 is for analog POTS, as H.320 is for ISDN and other digital services. MCI has announced a similar service.

Multipoint on the LAN should be shipping by the time you read this from ViewPoint Systems of Dallas. Other vendors are working on their multipoint systems, so expect to see more by the end of the year or by spring 1996.


ISDN was introduced more than a decade ago, but its growth has been as slow as molasses. Now it's almost here. By the end of 1995, the telcos are expected to offer ISDN to 75 percent of their customers. Some as high as 90 percent. ISDN has become the de facto wide area standard for videoconferencing.

ISDN's basic service, known as Basic Rate Interface (BRI) provides 128 Kbps bandwidth, four and a half times more than a V.34 modem. This 128 Kbps is often throttled down to 112 Kbps (two 56 Kbps channels instead of two 64 Kbps channels) if there are long distance connections or older equipment in the central office, but 112 Kbps can deliver reasonable video performance.

Room systems from PictureTel, CLI and VTEL start in the $20,000 range and go up from there. Desktop ISDN systems such as PictureTel's PCS, Intel's ProShare, AT&T;'s Vistium and VTEL's S-Series range from $2,000 to $5,000 per seat. Intel has worked a subsidy deal with the telephone companies similar to purchasing a cell phone, and if you agree to keep your lines for x number of months, you get ProShare for $999.

Desktop systems come with data collaboration and conferencing software, a camera and boards that perform the video capture, video and audio compression (the codecs), and ISDN attachment. Unfortuneately, most systems come on two boards and need two free bus slots.

Another downside is the fact that the boards are used only for videoconferencing. Waltham, Mass.-based VIVO Software's Vivo320 system so far stands alone in using a software codec. It keeps the per-seat price down to under $2,000. VIVO uses third-party ISDN adapter and video capture boards that can be used for any ISDN transmission and video capture job, not just videoconferencing. VIVO's doing what many in the industry feel will become mainstream - that the differentiation will be in the software.

Compression Labs is selling Intel's ProShare for ISDN and LAN, because it feels desktop videoconferencing hardware will become just another PC commodity, and further investment in this technology isn't going to pay off. It is thus concentrating on developing data collaboration tools that will allow room systems and desktops to work together. Perhaps it's a wait-and-see strategy. Videoconferencing over the LAN is, after all, a new ballgame.

Pots Service

If all you want to do is look at the person you're talking to, you can already do that with AT&T;'s VideoPhone 2500. It's a regular POTS telephone with a camera and small color screen. It's maximum video rate is 10 frames per second, one third the rate of TV, and noisy lines will reduce that even further. AT&T; has licensed this technology to Hitachi, JVC, Sanyo and Sharp, so while VideoPhone street prices are already less than $1,000, expect serious competition and lower prices.

What a VideoPhone doesn't give you is data collaboration, and that's why computer-based POTS videoconferencing systems are emerging. With POTS-based systems, there are no ISDN fees, and no more waiting for ISDN lines. Although, dial-up video would have been unthinkable before today's V.34 modems came on the scene, even at 28,800 bps, you're still only going to get a handful of frames per second. You can't make gyrating motions either, or the whole thing flakes apart.

Milpitas, Calif.-based Creative Labs and Irvine, Calif.-based Alpha Systems Lab both offer POTS videoconferencing. Creative's ShareVision and Alpha's MegaConference systems cost about $1,500 per seat and provide point-to-point, PC-based solutions that are proprietary. You need the same unit at both ends. VIVO and others are developing POTS systems, too. Alpha claims its MegaConference system can be easily software upgraded to the new H.324 standard when it is finalized.

POTS-based systems could be ubiquitous by Christmas. Personal use will drive this application as much as business.

LAN-Based Systems

The obvious advantage of LAN-based videoconferencing is that the LAN is in place, and everybody is hooked up to it. The ITU is working on its H.32Z LAN conferencing standard, but it won't be completed until 1996. H.32Z promises a standard way to send data over the LAN. In the meantime, proprietary LAN solutions are surfacing.

The quality of LAN-based videoconferencing depends on the technology used to send video over the network as well as the configuration of your network. Intel claims 12 to 15 frames per second over the LAN with its ProShare system, while Dallas-based ViewPoint Systems guarantees 30 frames per second with its Personal Viewpoint system. ViewPoint fixes the frame rate at 30 frames per second and varies the resolution depending on network traffic. By lowering the resolution where motion is high, a smoother overall picture fluidity is simulated at a lower bandwidth.

Personal ViewPoint also uses the IP multicasting feature and should be deliverable in its multipoint version by the time you read this. You have to install a TCP/IP stack into each machine, but the software is free from Microsoft. ViewPoint says it has engineered an extraordinary way to do videoconferencing transmission over packetized LANs without stealing precious bandwidth. Its multipoint system is capable of five-way videoconferencing for about $2,000 per seat.

The company that does LAN-based videoconferencing right - and does it on legacy LANs - ought to do very well. But you're going to have to check this out very carefully. Pundits claim 10BaseT Ethernet (10 Mbits/sec) networks are going to be dragged to their knees by videoconferencing, but ViewPoint claims no sweat on 10BaseT. Network administrators are going to have a lot of fun over the next couple of years with this one. What's true today is not true tomorrow, so those planning LAN videoconferencing will need to stay on top of it.


Multipoint video on a LAN doesn't exist yet, and ISDN lines hooked up to several desktops means monthly telephone charges to conference with your colleagues two floors below you. San Antonio, Texas-based DataPoint Corp. and Wilmington, N.C.-based Target Technologies take a different approach. You do your data collaboration over your existing LAN, while the video travels over its own twisted pair network. The results: superb TV-quality video at somewhat higher cost initially, but what may prove a more intelligent investment in the long run.

Another advantage of the system is that, since it's pure analog video, any proprietary conferencing system can hook into it via a codec, which converts the proprietary-compressed code into NTSC (TV standard) video, which is its common denominator.

Just More High-Tech Hype?

I don't think so. For some, it might be a fad in the beginning, but one of the things that will surely happen is that we will be able to develop stronger relationships with co-workers than we ever could using the telephone.

But I feel certain that video communications is going to be better than that. First of all, it will be transparent in use, because the systems that aren't will fall by the wayside. All the ways in which we will take advantage of this new medium are yet unknown. But it's starting. Now is the time to prepare. The purpose of this new technology is to improve the quantity and quality of work that your agency is doing.

Alan Freedman has been in the computer business for the past 35 years and is the country's most noted computer lexicographer. His Electronic Computer Glossary is an award-winning mini-encyclopedia of computer terminology, concepts, products and players with more than 8,000 definitions from micro to mainframe.

The fully-hypertexted Windows and DOS versions take 2.5MB hard disk space and cost $34.95 from The Computer Language Company, (215) 297-8082 (FAX 8424).