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In an ideal videoconferencing solution, the goal is to make the technology as transparent as possible, so the conference feels much like a natural face-to-face meeting.  In order to achieve this, a variety of advanced technologies are necessary.  This information below highlights some of the basic technological terms and concepts of a successful videoconferencing system.

Videoconferencing Solutions Can Be Organized Into 3 Main Categories:

1 – Integrated Systems

This is the solution of choice for fixed corporate, educational, and government environments.  All equipment is permanently installed, providing the highest quality and ease of use.  The equipment runs over a corporate LAN or can utilize ISDN or IP networks.  These systems are appropriate for formal rooms and/or to facilitate larger groups.

Videoconferencing System Components

Camera

The main camera is critical to the overall quality of the system.  In many cases a single camera is installed to capture video at each end of the call, while integrated systems may feature multiple cameras in order to provide a greater range of viewing angles.  Features such as zoom, pan and tilt add functionality that can enhance the overall user experience.  Variables such as the size of the room, number of users, seating plan an expected usage should all be considered when specifying a camera.

Audio Components:  Microphones and Speakers

Seeing quality video is important for a meeting, but hearing the proceedings is essential.  Most expert designers consider High quality audio as important or more important than video.  You need a microphone for capturing local audio and speakers for playing the sound received from the far end.  Features such as noise suppression and echo cancellation can make an appreciable difference in the perceived sound quality and should be evaluated as part of the system design process.

Codec

The Codec is the heart of the videoconferencing system.  The word itself is shorthand for “Coder/Decoder” and describes the function of the equipment.  Audio and video data create enormous amounts of digital data, and without compression simply could not be delivered over digital networks.  The codec takes the audio and video captured at your site and compresses the digital data so that it can be transmitted efficiently; when the data arrives at the other end of your conference it is received and decompressed for viewing.

Display

The video being received from the far end is viewed on a display monitor, which can be a computer screen, plasma, or TV.  While factors such as screen size, brightness and resolution all play a role in the quality of the image, the performance of the codec and the amount of bandwidth available have a more direct affect on image quality.

User Interface

The user interface is what brings the system to life for users.  It allows people to dial calls, control and adjust the various components of the system, and launch other presentation devices (such as a VCR).  Creating an effective user interface requires mastery of the various hardware and components of the system as well as a thorough knowledge of the “culture of use” within an organization.

2 – Roll-abouts

The hardware used for roll-about solutions is housed on a mobile cart which allows videoconferencing in multiple rooms using the same system.  While the operating quality of the system remains intact, variables such as lighting, sound quality, and ease of dial up/network access can suffer as the equipment moves between various locations.  Roll-abouts are appropriate for small, less formal rooms where the need for increased flexibility and mobility takes precedence over image quality.

Networking Considerations

High quality videoconferencing is bandwidth dependent, and bandwidth is a function of your network connection.  Videoconferencing can operate over the internet, a private network, or the public telephone system.  Determining which is most appropriate depends on multiple factors such as availability of bandwidth, the most appropriate configuration of your company’s network, the number of users, the expected number of calls, and whether you’ll be making point-to-point or multipoint calls.  ISDN is a popular choice for videoconferencing because it provides a purely digital, high bandwidth network.  IP networking utilizes the internet and has become a viable option as internet access, reliability, and bandwidth have increased.  Presently, approximately 15-20% of all videoconferencing units utilize IP while nearly 80% are still connected via ISDN services.

Standardization

In order to ensure that systems are able to work with each other independent of brand and or system type, a number of standards have been developed by the International Telecommunications Unit (ITU).  You’ll see and hear these standards referred to by different equipment manufacturers when describing their products.

H.323 provides specifications for voice and video communication over an IP network.

H.320 provides specifications for voice and video communication over ISDN lines.

H.324 provides specifications for voice and video communication over traditional phone lines.

3 – Desktop Solutions

These are designed for a single user and are typically installed on top of a computer monitor.  Utilizing IP and/or LAN connectivity, these are an effective, reliable and affordable way to begin utilizing videoconferencing or to implement it widely for satellite offices or telecommuters.  Image and audio quality meet acceptable business standards depending upon LAN traffic.

 

Last modified: January 10, 2005
Yannis Grammatis