videoconferencing

(redirected from desktop conferencing)
Also found in: Acronyms.

videoconferencing

[‚vid·ē·ō′ kän·frəns·iŋ]
(computer science)
Two-way interactive, digital communication through video streaming on the Internet, or by communications satellite, video telephone, and so forth.

videoconferencing

A real-time video session between two or more users that reside in two or more locations. While videoconferencing supports several end points communicating, the terms "video call" and "video chat" generally mean one-to-one. See video calling.

Although AT&T unveiled its expensive Picturephone at the New York World's Fair in 1964, there were few takers. Today, due to high-speed cable and DSL service, video calling has become commonplace for the consumer in the form of Apple's FaceTime and Microsoft's Skype. See FaceTime and Skype.

In the 1970s, business videoconferencing was established between branch offices, and by the early 1980s, more inhouse systems became popular after Compression Labs pioneered highly compressed digitized video. Digital video is delivered in various resolutions and frame rates starting at 128 Kbps up to multi-megabits per second.


Room Systems - The Beginning
In the early 1980s, videoconferencing emerged with room systems like this unit from Tandberg (the company was acquired by Cisco in 2010). (Image courtesy of Tandberg, www.cisco.com)







On the Desktop
Desktop videoconferencing became more widely used after the universal adoption of IP protocols in the late 1990s. Polycom's PVX software turns a Windows PC into a videoconferencing system. (Image courtesy of Polycom, Inc., www.polycom.com)







ISDN and IP
ISDN was the traditional transport for private videoconferencing because it provided dedicated 64 Kbps channels that could be dynamically allocated. However, ISDN gave way to the Internet protocol (IP). In a private IP network deployed by either the enterprise or via carriers, the quality can be controlled.

Using the public Internet as transport provides reasonable quality without additional cost. Although congestion is inevitable, systems can throttle down to lower frame rates to eliminate most of the jerkiness.

Multipoint Conferences and Telepresence
A point-to-point conference between two people is straightforward, but a conference with several people requires moderating. A multipoint control unit (MCU) is used to mix the audio and make the video of the dominant speaker the larger window on screen (see MCU). Multipoint conferences are also achieved by connecting to a carrier's conferencing network service. A more immersive environment for group meetings is achieved with multiple monitors and loudspeakers (see telepresence).

Firewalls
Firewalls often presented a problem for Internet videoconferencing because they are designed to block packets that were not previously requested. However, there are numerous ways of configuring routers and firewalls to accept videoconferencing data. Another option is to place the video system in the demilitarized zone (between the private network and the Internet). See DMZ.

Video PBXs
Like a telephony PBX, a video PBX is used to switch calls and provide call forwarding and call transfer. Video network management is also required to adjust bandwidth, provide quality of service (QoS) and to log calls for accounting purposes. See videoconferencing standards.
References in periodicals archive ?
As mentioned earlier, Intel's foray into this market is seen as a boon; many believe desktop conferencing will become virtually commonplace in the near future because of the firm's name recognition and ability to invest considerably into partnerships that will help lower costs and improve the technology.
"Due to our security requirements, ISDN is not a viable desktop conferencing option for most of our customers, who are connected to a private internal network," says Berry.
We are interested in more sophisticated groupware products, commonly referred to as "desktop conferencing" software.
Table 1: Desktop Conferencing Products & Vendors
True desktop conferencing programs provide a software environment, usually run over LANs, that enables students to share documents and engage in real dialog, debate and analysis.
Some desktop conferencing systems are too expensive for the typical school.
The VIU provides a `bridge' that connects such legacy systems as H.320-compliant videoconferencing room, rollabout or small group systems to H.323-based desktop conferencing networks.
Low-speed desktop conferencing works best when viewing text, documents, or spreadsheets.
Any desktop conferencing network should support both switched and packet networks.
Using a customized version of PictureTel PCS-100 desktop conferencing product, Project DIANE members can engage in high-quality voice communication, have a full screen two-way video conference, draw pictures and type words to one another in real time, or collaborate with each other by remotely sharing DOS or Windows software.
With a video link - remember, ISDN is ideal for desktop conferencing - those remote workers can get the face-to-face contact that keeps them fully involved members of the team.
When enough business people demand desktop conferencing, and enough grandparents demand videophone capabilities so they can see the grandkids across the country as they talk to them, then ISDN will roll out.