8.1    Introduction to Framework Design

Before presenting the architecture of Tema, the notion of a framework and three principles for designing one are discussed. The structure of the chapter is also outlined.

8.1.1    What is meant by a framework?

The notion of a framework for enterprise modeling has been defined by ISO/ANSI (1994:8) as follows (italics added):
"A framework [for enterprise modeling] is a skeletal structure that provides a context and a set of rules for the use of systems and modeling concepts for enterprise modeling. The resulting models need to describe the elements which are present in real systems, such as: material, energy, resource, information flows, and organizational phenomena. The models also have to accommodate the requirements of the users of these models, whose purposes vary over time according to their responsibilities, objectives, and the processes being considered."
Although the above definition is given in the context of computer-integrated manufacturing and focuses more on properties of models than on the process of modeling, the definition includes four main concerns that Tema must discuss and incorporate:
 
The context of enterprise modeling
The context is the assumptions and requirements to organization and infrastructure that have to be available in order to do enterprise modeling according to the framework (in a sense, preconditions for modeling).
A set of rules for the development and use of enterprise models
A set of rules refers to the methodological aspect, and even if not a set of rules is provided, Tema at least has to discuss some guidelines for modeling.
The concepts employed in enterprise models
By concepts is here meant both modeling language and general properties of the artifacts that may be developed in an enterprise modeling project.
The user requirements to the artifacts
User requirements refer to what the actors expect or intend to attain by developing and using models i.e., what are the objectives of enterprise modeling  within the framework?

Notice the resemblance between the above listed requirements to what constitutes a framework and the OPPO framework discussed in section 5.2.4: Context roughly corresponds to organization, set of rules refers to process, model concepts belong to the product aspect, and user requirements to models are clearly objectives.

8.1.2    Criteria for design of a framework

When developing a framework, there are always underlying assumptions and subjective values that guide the design. These assumptions ought to be explicitly discussed. For Tema, three criteria are considered: Fit with principles, practical applicability and presumptionism. The reasons for choosing these criteria will be discussed briefly along with each criterion. How Tema meets the criteria will also be evaluated in chapter 10.

Fit with principles

A first design criterion used in Tema is the degree of compliance with the principles outlined in chapter 7. Assuming that the assertions made about enterprise modeling practice are valid (or at least plausible), Tema is designed to fit this practice.

The reason for including the criterion is obvious: Throughout the research project, considerable effort has been spent on studying enterprise modeling practice. The principles in chapter 7 represent the essence of these studies the lessons learned. Not taking these into account when designing Tema would not make sense.

Practical applicability

The second design criterion is the degree of practical applicability. By practical applicability is meant how high the barriers against use are, and the requirements to tailored, advanced or expensive equipment and software. Practical applicability influences the preconditions that have to be satisfied in order to apply Tema.

Tema is based on studies of practical modeling, and applicability according to this practice is hence the ideal. In situations where observed practice failed, Tema proposes and argues for solutions that are perceived to meet the requirements with low demands on resources.
 

Communication-intensive activities can be envisioned supported in many ways by computers in networks. Powerful real-time communication facilities with dedicated equipment, tailored software and virtually unlimited communication bandwidth might be a dream of some actors. Requiring this kind of technology to support Tema would violate the design principle of practical applicability. Tema proposes off-the-shelf solutions whenever possible. 

The main reason for including practical applicability as a design criterion in addition to the "fit with principles" criterion is to deal with the situations where observed practice did not work well (e.g., definition of terminology in TEK-S). In these situations, an assessment of perceived applicability of the proposed means must be made based on personal experience, others' documented experiences, literature studies or other arguments.

Presumptionism

The third design criterion concerns presumptionism. Presumptionism concerns to what degree a modeling approach rests upon assumptions about the Universe of Production or the Universe of Modeling, and thereby constrains the flexibility available to modelers. Alternative attitudes towards presumptionism in conceptual modeling has been discussed by Sindre (1990:17ff).

At one extreme, there is the stance that one should have no presumptions at all. All languages and methods must be invented as a part of the modeling effort. Every new problem requires a unique and tailored solution. This leads to a high degree of flexibility, but may be inefficient and miss the benefits of learning from other practitioners and theorists. Incapability of action may also be a consequence.

At the other extreme, there is the stance that all language concepts and methodical steps can be decided and fixed in advance. This might be highly efficient, but not necessarily effective (as lack of flexibility may prevent the modelers from solving the problem at all, or requires bending the approach to such a degree that the solution is useless). A detailed method can only produce one kind of artifact. The less flexible a method is, the more identical will the products be.
 

Presumptionism manifests itself in many ways. To offer an ontology of the Universe of Production is a presumption as it restricts which elements can be represented in an enterprise model. Likewise, developing an ontology of the Universe of Modeling restricts the way enterprise modeling is performed (but not necessarily what can be represented).

Tema is designed to be flexible at the expense of possible efficiency. The main reason is the kind of modeling that is sought supported: Enterprise modeling that dominantly involves sense-making and not mere representation.

The reason for including presumptionism as a design criterion is the perceived lack of both support and flexibility in current frameworks for enterprise modeling. Seeing enterprise modeling as essentially an act of sense-making instead of an act of representation implies a need for a shift in modelers' attention.

8.1.3    Outline of the presentation

The presentation of Tema starts with a discussion of the overall framework in terms of the four concerns context, rules for use, concepts and user requirements (section 8.2). The graphical illustration of the terminology in Figure 7.1 is reused in a modified version to stress the fit between the principles and the framework. Main consequences of applying the design criteria are pointed out wherever appropriate.

Elements of the framework are then presented and discussed according to the two main phases of enterprise modeling: The development phase (section 8.3) and the dissemination phase (section 8.4). Each phase is first presented in terms of an illustration followed by objectives, process, artifacts, modeling organization, forums and media.

The chapter is closed by an outline of a few possible technological solutions for supporting Tema, followed by concluding remarks.