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====== Discussion of MVF Usage Scenarios ====== All scenarios involve the idea that the model elements of a model (or metamodel) correspond to concepts that have accepted designations and definitions in some stakeholder communities, and those communities may use different natural languages. We want to support all of these cases, but it seems clear that the requirements can be derived entirely from Case 3 and Case 5. The rest is usage guidelines. (The RFP describes all these scenarios, but not quite this way.) ===== Scenario 1: Tool-based vocabulary support ===== The user creates the model elements and explicitly provides the terms and definitions for the concepts represented by (some of) the model elements, in one or more languages, using a feature provided by the modeling tool. The modeling tool stores the terms and definitions in its internal model repository and is able to use this terminology in interactions with the user. [fac] I don’t believe you can separate the metamodel MVF capability (your case 6) from this case. The terms of the metamodel will appear in modeling displays and should be expressed in the preferred language (vocabulary) of the user. This case does not need MVF. ===== Scenario 2: Tool-based vocabulary support with model and vocabulary export ===== Like Scenario 1, but the modeling tool can export the model with the business vocabulary entries and links in a form that can be used by other modeling tools, at least for the same modeling language. This case requires MVF to specify * a standard export form for the vocabularies, and * a standard way to link the model elements to the vocabulary entries. Ideally, the linkage should be an additional property for MOF:ModelElement. ===== Scenario 3: Model linked to external vocabulary only ===== Unlike Scenarios 1 and 2, the modeling tool can import a business vocabulary that is independently developed and maintained (by another tool) in a standard form, and enable the user to link the model elements to concepts/terms/definitions in the imported vocabulary. In addition, the modeling tool can import and export models with links to externally maintained vocabulary entries. The modeling tool need not be able to create or maintain a business vocabulary; it does need to support user search of the vocabulary. This case requires the MVF to specify: * an exchange representation for a business vocabulary independent of any model, preferably an existing standard or standards, or a subset thereof, and * a standard form of links between model elements and vocabulary entries from a separate resource. ===== Scenario 4: Modeling tools with import/export of vocabularies ===== This scenario combines the capabilities of scenarios 2 and 3 in the modeling tool. The modeling tool can import an existing business vocabulary, enable the user to modify it, or to create new vocabularies, and export vocabularies. The tool can import and export models with model elements linked to the vocabulary entries. The modeling tool itself can act as a vocabulary management tool, more or less independent of any model. This case requires exactly the same MVF features as Scenario 3. ==== Subcases ==== These cases (from Fred) seem to be about reconciling a user-specified vocabulary with other business vocabularies associated with, or independent of, existing models. They apply to Scenario 4, where the modeling tool also serves as a vocabulary management tool. === A: Vocabulary for the active model === The vocabulary is for the same model. The user must examine the terms of the imported vocabulary and correlate them with the terms of an existing, internal vocabulary maintained by the tool. The structure of the model will be very helpful if the user can view the sending model and the receiving model for comparison. === B: Vocabulary for a different model in the same language === The imported vocabulary is from the same business domain/discipline/enterprise but is linked to a different model in the same modeling language. Some of the concepts may be shared by the two models, and links from the active model elements can point to the matching concepts, so alignment for these will be simplified. This could be used to develop a unified vocabulary for a business domain, combining the existing, internal vocabulary with the imported vocabulary to create a reconciled vocabulary. However, since the models are not the same, differences in the semantics of model concepts may be more difficult to recognize. === C: Vocabulary not associated with a model supported by the tool === The imported vocabulary is NOT for a model created with the same modeling language but is for the same business domain/discipline/enterprise (if the domain/discipline/enterprise is not the same, then reconciliation of semantics will be even more difficult). === D: Universal vocabulary === The imported vocabulary is a "universal" vocabulary or set of vocabularies for a set of universal concepts. The user must reconcile concepts based on natural language semantics of terms and definitions in both the internal vocabulary(s) and imported vocabulary(s). The existence of this universal vocabulary might evolve from efforts of standards or professional organizations, but it represents a major investment and years before it provides business value to users. A "universal" vocabulary might be more useful if it is supported by a concept taxonomy that enables a user to find appropriate general concepts leading to needed specializations or add specializations as needed in order to reconcile the internal concepts with the imported concepts. However, given that the concepts can be identified and appropriately specialized, there is still a major investment in many vocabularies for subsets of the concepts to reflect terms/designations for different communities (different natural languages, different disciplines, different enterprises). === Formal language formulations in vocabularies === [fac] Case 3(e) the vocabularies include semantic formulations in a standard, formal language so that corresponding concepts can be automatically identified. This would be great, but it requires vocabularies for the formal language elements and additional concepts for the elements needed for precise formulations. This represents a substantial investment for specification of formulations and associated vocabularies. Maybe SMIF will address this. Once the formulation language and concepts are established, then the formulations for individual concepts must be specified. This is not likely to be a task for typical users of the modeling tools, and there must be business value realized by the developers of these formulations. ===== Scenario 5: Model linked to access-controlled vocabulary ===== This scenario is like scenario 3 on the model management side, but the business vocabulary is not available for import. It is controlled by a service that maintains it and does not export it, but rather provides interfaces for accessing concepts, terms and definitions for different speech communities. The modeling tool provides user access to the vocabulary services and enables the model elements to be linked to vocabulary items as maintained by the service. The modeling tool can import and export models so linked. This case requires MVF to specify * a standard API for a Vocabulary Service, so that modeling tools can access such services. It is not to be expected that such a service will expose a means of modifying the vocabulary it maintains. Controlled vocabularies may well involve an elaborate review process for modifications. ==== notes ==== [fac] This is Case 3(e) with the universal concepts and vocabularies provided by a service and therefore an enterprise that has made the investment and realizes business value by providing the service with mechanisms to prevent unauthorized copies. ===== Scenario 6: Terminology for a metamodel ===== The "business vocabulary" is extracted from the language specification in the standard form (somehow). A UML/MOF tool provides (per Case 2, 3 or 4), for linking the metamodel elements to the specification vocabulary elements. In addition, translations of the specification vocabulary to other languages may be constructed and exported, and a UML/MOF tool may import them and link the metamodel elements to the corresponding vocabulary items. A modeling tool can import the metamodel with the links and use the multiple language terminologies in dialogues with the user. -- This case requires the same MVF features as Case 3. [fac] The tool provider(s) (or the metamodel submitters) should provide the vocabulary of the modeling language specification (terms and definitions from the spec). Tool vendors (or vocabulary vendors) may provide alternative vocabularies for the metamodel. This reduces the user burden and should have market value at least for the tool vendors. ===== Scenario 7: Metamodel-specific tooling ===== Same as Scenario 6, except that the tool that maintains and links vocabularies to the metamodel is not a general-purpose UML/MOF tool, but rather a tool that internalizes a specific metamodel. Such a tool is essentially an adjunct to a modeling tool for that specific modeling language. [fac] I'm not sure what this means. The modeling language implements the metamodel and should be able to link to vocabularies for the metamodel the same as for models created by the user. -- This case may require nothing but proprietary capabilities, but for exchange purposes, if that is wanted, it requires the same MVF features as Case 4. ===== Issues ===== As worded above, the only link between the terms and definitions for the same concept in multiple language vocabularies is the model element (which would satisfy the RFP intent). It should, however, be possible in creating and maintaining vocabularies to make such links as annotations to a vocabulary entry, and then to include those links in the exported vocabulary file. [fac] Note that for a particular modeling language, vocabularies will likely be shared as defined for existing models. A user will either import a model with vocabularies and then modify the model, adding needed concepts, or will import the vocabularies and use the existing model for reference to reconcile to the shared concepts.
