CallHub Support
CallHub tracking is a new feature in TAPI version 3.0. CallHub functionality was added to the TAPI 2.1 programming elements with the delivery of Windows 2000. A CallHub represents a third-party view of a call, and TAPI's call handles represent the first-party view of a call. With CallHub tracking, the service provider is requested to follow CallHubs and give information about the call during the lifetime of a CallHub. As new parties join and leave the CallHub, the service provider should inform TAPI.
A service provider does not need to implement any new functions in order to support CallHub. It simply needs to fill in the dwCallID member of the LINECALLINFO structure. In TAPI 3, TAPI collects all calls with the same dwCallID and creates a CallHub handle that the application can use to track the call.