Videoconferencing and Videotelephony: Technology and Standards, Second Edition
A concise and complete introduction to the design and deployment of standards-based videoconferencing and videotelephony applications.
TABLE OF CONTENTS Videoconferencing and Videotelephony: Technology and Standards, Second Edition
Glossary
- Adaptive differential pulse code modulation
- A form of differential pulse code modulation that uses adaptive quantizing.
- A-law
- A PCM coding and companding standard used in Europe. One common use is for digital voice communications.
- Analog-to-digital (A D) conversion
- The conversion of an analog signal to a digital signal.
- Asynchronous
- A transmission method in which units of data are sent one character at a time preceded and followed by start/stop bits that provide timing (synchronization) at the receive terminal.
- Audiovisual
- Involving both hearing and sight.
- Bandwidth
- The amount of information that can be sent over a given transmission channel, expressed typically as a frequency range or as bits per second. Roughly equated with speed. Typical transmission services are 64 and 128 Kbps, 1.544 Mbps (T1), and 45 Mbps (T3).
- Basic rate
- Formally called the basic rate interface (BRI), one of two "interfaces" defined in ISDN. BRI provides two B-channels at 64 Kbps and a data D-channel at 16 Kbps. Defined for links to the home.
- Baud
- Unit of digital transmission signaling speed derived from the duration of the shortest code element. Speed in baud is the number of code elements per second, also commonly referred to as symbols per second. Most modems today operate at 2400 baud. If the symbol captures 6 bits of information (V.32bis), then the 2400-baud modem can send 14,400 bits per second.
- B-channel
- A "bearer" channel that is a fundamental component of ISDN and B-ISDN interfaces. It carries 64 Kbps in either direction, is circuit switched,...
A-C
Copyright Artech House, Inc. 1999 under license agreement with Books24x7
