Appendix C: Glossary and Acronyms

LED Light-emitting Diode

Linux

A robust, feature-packed open source operating system based on Unix that remains freely available on the internet. It boasts dependability and offers a wide range of compatibility with hardware and software. Asterisk is supported exclusively on Linux.

loopback

A state in which the transmit signal is reversed back as the receive signal, typically by a far end network element.

MGCP Media Gateway Control Protocol

multiplexing

Transmitting multiple signals over a single line or channel. FDM (frequency division multiplexing) and TDM (time division multiplexing) are the two most common methods. FDM separates signals by dividing the data onto different carrier frequencies, and TDM separates signals by interleaving bits one after the other.

mux multiplexer

A device which transmits multiple signals over a single communications line or channel. See multiplexing.

node

A terminal in a computer network.

Digium, Inc.

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