In voice telephony the term MOS, or mean opinion score is a measurement of the quality of human speech at the destination end of the circuit. MOS is expressed as a single number in the range of 1 (lowest perceived quality) to 5 (highest perceived quality). The MOS is an important factor in determining the QoS.
- media gateway
The terms media gateway and VoIP gateway are used synonymously, however, where VoIP gateway refers specifically to VoIP communications, the term media gateway includes additional media (e.g. video).
- media gateway controller
Abbreviated as MGC, media gateway controller is a system used in some VoIP architectures. MGC handles the registration and management of resources at the media gateway. A media gateway controller exchanges messages with central office switches via a signaling gateway. A media gateway controller is sometimes called a call agent, call controller, or softswitch.
- media server
In Internet and online communications, the media server processes all multimedia applications, such as call distribution, on-demand faxing, e-mail programs and others. In VoIP specific applications, the media server possesses and generates the media streams and handles all functions related to tasks such as decoding tones, bridging multiple streams, processing scripts, and recording audio.
- medium dependent interface
Abbreviated MDI, an Ethernet port connection that allows network hubs or switches to connect to other hubs or switches without a null-modem, or crossover, cable. Compare with MDIX. A medium dependent interface is also referred to as an MDI port or an uplink port.
In decimal systems, the prefix mega means one million, but in binary systems, mega stands for 2 to the 20th power, or 1,048,576. One megabyte, therefore, is either 1,000,000 or 1,048,576 bytes (this is equivalent to 1,024K), depending on the context.