The first model in Model Driven Architecture (MDA) is a Computation Independent Model (CIM) that specifies domain information. One of issues discussed in this chapter is the meaning of “computation independence”. Another one is formalism of CIMs. And the last issue discussed is a use of a Topological Functioning Model (TMF) for problem domain modeling from a computation independent viewpoint. The TFM is a mathematical model that holistically and formally represents functionality of the problem domain, and does not show any details of the implementation and modeling platform. The TFM contains information from functional, information, and organizational domains of business process modeling. Construction of the TFM from the informal description of the system and guidelines for its decomposition into business processes are discussed and demonstrated by an example.
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When we try to answer questions about the computation independent model asked in Introduction, it is worth to overview academic researches and results in application and understanding of this model.
As mentioned in Introduction, the CIM is a domain model or a business model. The term “business model” and related terms such as “a business fact”, “a business rule” and “a business process” originated from business modeling. According to (Hendryx, 2003a, para. 2), a business model is a precise description of the business in its environment, by the business, in the language of business people, dedicated to business purposes (not necessarily IT). A model can be textual, tabular, graphic or a combination of them. If underpinnings of the business model are formal, then it is possible to handle this model by machine. Moreover, different objectives can require different models, thus it is necessary to determine purposes of construction of business models. The definition in (Hendryx, 2003b, p. 1) extends the previous one with the statement that “A business model provides comprehensive answers to the six basic interrogatives: What? How? Where? Who? When? Why?”.
Thus, a business model reflects some business knowledge. Usually business knowledge is expressed using words and phrases that business people know and understand, i.e. in other words by using terms. Business facts are constructed using these terms as foundations, and express things that business peoples know about their own businesses. Business rules make a use of facts in order to help in control of business operations and to ensure that business is executed in the way required by business people (Chappel, 2005). Besides that, a business process can be considered as a category of a business model that focuses on transforming input resources to the output in order to add value for people inside and/or outside the business (Hendryx, 2003b). Summarizing, a business model is able to reflect those parts and rules of business that are not related to computerized information systems as well as those ones that are related to computerized information systems.
Hence, the CIM is mainly oriented on the business people. However, a discussion of what is to be modeled in the CIM and how the CIM can be organized is held still. Thus first we need to understand what does it mean “computation” and “computation independent” in the context of system modeling?