Every filter is contained in a separate DLL that must export two entry-point functions, GetFilterVersion and SvrFilterProc. When EAS initially loads a filter, it calls the filter's GetFilterVersion function and passes a pointer of DWORD to the function as a parameter. The filter SHOULD pass back its notification type by this parameter to EAS.
Every event triggers EAS to call the corresponding filter dll's SvrFilterProc function and pass a pointer of structure to the filter. After the filter processes this event, a return value is passed back to EAS to notify it to perform specified actions.