Call waiting with “Caller ID” uses a special signal in
order to warn you about an incoming call, during another call there are shown the
name and number of the calling subscriber on the display. The function also
allows switching between two calls.
Multiple call arrangement - allows the user to receive several calls simultaneously, even if they came by the same line. This stops the redirection of incoming calls directly to voice mail in case the line is busy or if the user is already involved in an active call.