The IInetLogInformation::GetPortNumber method retrieves the number of the port the client is connected to.
virtual DWORD STDMETHODCALLTYPE GetPortNumber( VOID);
Logging modules should query for this method if a server instance has set the MD_EXTLOG_SERVER_PORT flag of the MD_LOGEXT_FIELD_MASK metabase identifier.
LogExtFileServerPort, MD_LOGEXT_FIELD_MASK