From inside your existing ATL project, open the Insert|New ATL Object… dialog in Visual Studio. Select the Objective Toolkit APP Object from the Stingray category. If this object is not available as an option, it is probably not registered properly. See the readme notes under the Utils\Toolkit\Template\AsyPlgProt directory.

Supply the necessary arguments and run the wizard to completion. This will insert the appropriate files and modify the IDL appropriately.

The inserted files provide a default implementation of IInternetProtocol, IInternetProtocolRoot, and IInternetProtocolInfo.

Before compiling the project, you have to provide an implementation of the SECWorkerThreadFetchObject class. And, if necessary, subclass SECPlugProtImp as well. Take a look at the app sample for pointers.