There are several advanced features and configuration options that can be changed for each phone service. When viewing a phone service’s configuration, click the Advanced Settings link to make these options visible. The advanced settings are described below.
Port field -- The port on the Server at which the service is provided (for VoIP services)
Authentication Username field -- Certain VoIP service providers use different “username” and “auth_username” values. Your provider should have told you if this is the case and provided you with the appropriate values to enter here.
DTMF Mode dropdown -- Mechanism to use to transmit key-presses on the phone keypad for interactive voice response menus. If your service provider is asking you to use “Inband” signalling for a VoIP Phone Service you should consider looking for a new provider, as this mode is not reliable. The default RFC2833 should be used unless your provider has explicitly asked you to use another mode
Dialing Prefix field -- (Short) String of digits to be prepended to all outgoing calls. This is normally used if your VoIP service provider requires a specific prefix.
‘From’ field as username in SIP Header checkbox -- Certain VoIP providers require that you send this header. Your provider should have notified you of this requirement if it applies to you.
Send Remote-Party-ID SIP Header checkbox -- Certain VoIP providers require that you send this header.Your provider should have notified you of this requirement if it applies to you.
Company Name field -- Caller ID Name to send when making outgoing calls.
Use For Outgoing Call checkbox -- Whether this Phone Service should be used for outgoing calls. Disable Phone Services (temporarily) to prevent them introducing delays in dialing when they are offline or disconnected.