Although two-way calling (call waiting) is deactivated on the Broadworks platform, the XSI/CTI interface delivers corresponding events for this.
However, the incoming ringing call is terminated by the platform 20-50 msec later.
Therefore a temporary suppression of the unwanted two-call is implemented in ECSTA for BroadWorks:
If ECSTA receives a callReceivedEvent on an active call on a line, the associated TAPI call is first set to "invisible".
250 msec later this call is reported to TAPI by a scheduler, if it is not reported as terminated again by the platform in the meantime.