In ProxyGen, you only need to specify the session model explicitly for SOAP Web services and Sonic ESB, because ProxyGen generates a different interface definition depending on the session model. (The default is session-free.) For .NET and Java Open Clients you do not need to specify the session model because the generated proxy is identical for both session models. It is the responsibility of the Open Client application to specify the session model as a run-time session property for connection to either an AppServer (session-managed) or an application service (session-free).

The session model is really a property of the application service, and the AppServer enables support for and determines the session model for the application service by the setting of the AppServer operating mode. The state-aware, state-reset, and stateless operating modes each specify support for the session-managed model; the state-free operating mode, alone, specifies support for the session-free model. The entire application, including the client and application service, must be programmed differently depending on the session model. The model affects your choice of object types used to define the Open Client interface. For more information, see OpenEdge Application Server: Developing AppServer Applications.