Audio Sampling Rate: How many times per second an analog audio waveform is digitally sampled, i.e. takes a “digital snap shot” to create a digital representation. The more samples taken, the higher the fidelity.

Automatic Gain Control (AGC): An adaptive system where the average signal level is used to adjust the gain to an appropriate level for a range of input signal levels. AGC effectively reduces the volume if the signal is strong and raises it when it is weaker.

Client: A VCOM specific term to refer collectively to either a Control Panel or Device Interface.

Control Panel: VCOM’s client-side GUI enabling users to conduct communications using color coded selectors which represent audio/voice channels. Device Interface: VCOM’s client-side software application that bridges VCOM with multiple external communications systems.

IFB: An abbreviation of Interrupt Foldback or Interrupt Feedback. It is sometimes referred to as PI (Program Interrupt). In radio and television broadcasting IFB serves as a voice cueing mechanism for on-air talent. The talent listens to a program audio signal which can be interrupted by the voice of a production person (such as a director or producer) for the purpose of giving instructions to the talent regarding the show in progress. This is seen by a television viewer as the earpiece that a news announcer wears in the ear.

ISO: A high level intercom function by which a temporary and private communications link is established between an operator who is located at an intercom control panel and another operator. The derivation of the term ISO is from the word isolate. The function is valuable wherever a short term private exchange is required between two operators who are normally sharing the conversation required to accomplish a group activity. When any two people need to talk together without interfering with or being heard by anyone else, ISO is the function required. The most common application is that of a video control operator and a television camera operator. 12

System Administration: VCOM’s client-side system administration application which allows for dynamic configuration from any workstation or the server hosting the Virtual Matrix. Server: Used interchangeably with “Virtual Matrix,” VCOM’s server-side audio summing/mixing engine.

SIP: Session Initiation Protocol (SIP) is a widely adopted signaling protocol for Internet conferencing, telephony, presence, events notification and instant messaging. By supporting SIP, VCOM can readily interface with many commonly used IP phones, IP phone systems, and other SIP-compliant devices.

VCOM: A non-blocking, all software multi-channel/multi-access Intercom over Internet Protocol (IoIP) based on a dedicated server, multiple client architecture. VCOM is engineered for professional, mission critical communications in broadcast, production, military, aerospace, and government applications.