The most fundamental decision to make when designing and programming a PAS for OE business application is what application model it will use, session-free or session-managed, or even if the application will use a mixed model. The decision of which application model to use, and how, depends on your particular application requirements, which cover all areas of the application, including network capabilities, available PAS for OpenEdge resources, and critical application functions.
Once you have determined the application model to use, you must design and build the application server procedures to support it. Typical applications (especially Open Client and SOAP Web service applications) start with development of a business application that you then make available to the client application using the appropriate ABL, Open Client Toolkit, or SOAP Web service tools. You can also use parallel development techniques appropriate to the client type to develop both sides of the application at the same time. Whatever approach you use, the application model, or models, that you choose fundamentally determines the options for application development that are available to you. For information on the differences between these two application models, see
PAS for OpenEdge and Client Interaction.
