# NaturalConference service definition

The NaturalConference service is a C function library component of NaturalAccess that provides conferencing capabilities on AG and CG boards.

NaturalConference provides the following types of functions:

- Functions for opening conference resources, creating conferences, and adding members to conferences.

- Functions for retrieving information about:

- Conference resources

- Conferences

- Members

- Functions for dynamically changing conference features and member capabilities.

## NaturalConference objects

A conference is created and managed through three interdependent entities:

Object | Description
--- | ---
Conference resource | A single digital signal processor (DSP) or a set of DSPs working together. When a conference resource is created, a set of DSPs is declared, providing uniform capabilities and features. A conference resource can be likened to a building, with the number of DSPs assigned to the resource representing the scale of the building.
Conference | A space created by the application on a specified conference resource. In the building analogy, the conference is a meeting room in the building. Initially, the room is empty. The number of participants expected is determined by the application creating the conference. An application can also add seats to the meeting after the meeting begins.
Member | An object created by the application on a specified conference. Adding a member to a conference is like a participant sitting in a seat in the meeting room/building analogy.

## Conference capabilities

NaturalConference capabilities can be enabled for a given conference or member. NaturalConference capabilities include:

- Automatic gain control (AGC) on input and output.

  Automatic gain control is an algorithm applied to incoming speech before compression and storage so that the amplitude of the stored speech is kept at a target level.

- Dual-tone-multi-frequency (DTMF) clamping.

  DTMF clamping enables the removal of any DTMF that is detected on an input signal.

- Tone clamping.

  Tone clamping enables the removal of single frequency tones used for signaling an analog interface.

- Echo cancellation.

  Echo cancellation is an algorithm for removing the portion of the received signal that was determined to be echo by comparison with the output signal.

- Talker privilege.

  Privileged talkers are always active talkers even when they are not speaking.

- Active talker detection.

  Active talker detection provides the ability to determine which participants are talking at a given time.

- Coaching.

  Coaching provides the ability to selectively control which conference members can hear chosen participants. This feature is typically used to enable a coach to listen to a conference and provide input to one or more colleagues without the knowledge of other conference members.

The board being used determines the capabilities available to an application. To regulate system resources, the application can choose the capabilities to use. NaturalConference enables an application to query a conference object about its capabilities.