# Receiving inbound calls

In the NCC model for receiving inbound calls, nccAcceptCall accepts the incoming call, but does not answer or reject it.

When a Fusion gateway application receives an inbound call from a PSTN, it calls nccAcceptCall. After calling nccAcceptCall, the application waits for the associated NCCEVN_ACCEPTING_CALL event before invoking mspConnect. The receiving gateway then waits for the gateway at the opposite end of the network to place the call before the receiving gateway answers it.

- If the gateway at the opposite end of the network successfully places the call, the receiving gateway answers the call with nccAnswerCall and enables the connection with mspEnableChannel.

- If the gateway at the opposite end of the network is unsuccessful in placing the call, the receiving gateway rejects the call with nccRejectCall.

The following illustration shows function procedures for accepting inbound calls:

When receiving inbound calls, if the gateway application does not use nccAcceptCall, it still must wait for the MSPEVN_CONNECT_DONE event before answering the call with nccAnswerCall. In this case, however, the application cannot monitor the status of the call placed by the gateway at the other end of the network.

The following illustration shows function procedures for rejecting inbound calls:

For more information about NCC call control, refer to the Dialogic® NaturalAccess™ NaturalCallControl™ API Developer’s Manual.