# NCC call control parameters

The behavior of many NCC functions, and of the operating protocol, is controlled by parameters. These parameters are grouped together into structures. Each parameter structure has a set of default values that is sufficient for many configurations. You can modify the parameters to:

- Enable or disable function features.

- Adapt the function for exceptional configurations.

For example, when recording voice data, you can alter the function's behavior by modifying any of the record parameters that specify:

- Any subset of DTMF keys entered by the telephone caller that abort the function.

- Gain applied to the input signal.

- An initial timeout, which defines the time during which the caller must start speaking before the operation terminates.

- The amount of silence after a caller has stopped speaking before the operation terminates.

- Record-sync prompt frequency, amplitude, and duration.

- Automatic gain control settings.

The following parameters are available for CAS TCPs:

- NCC.X.ADI_PLACECALL

- NCC.X.ADI_PLACECALL.callprog

- NCC.X.ADI_START

- NCC.X.ADI_START.cleardown

- NCC.X.ADI_START.dial

- NCC.X.ADI_START.dtmfdet

- NCC.X.ADI_START.echocancel

Refer to CAS TCP call control capabilities for more information.