NIEM has introduced several new constructs that move away from simple element inclusion. How do I map my business requirements to these new mechanisms (Associations, Roles, Augmentation, and Metadata)?
Associations, roles, and metadata implement the ID and IDREF XML mechanisms. Through the use of ID and IDREF XML data becomes less redundant; ID and IDREF also allow us to take a relational approach for defining data. This results in a less hierarchical and flatter XML file which moves away from using only element inclusion to associate objects.
Although it may not be readily obvious, associations, roles, and metadata do somehow exist in most sets of business requirements. In many cases these may not be easily noticeable in their native form, so the tricky part is being able to pick these out and translate them to NIEM constructs. This underscores the importance of having an experienced and NIEM-cognizant facilitator to assist during the domain modeling phase of the IEPD process. The facilitator's job is to keep in mind the NIEM while considering the input from subject matter experts (SMEs). It should not be assumed that SMEs have previous knowledge of the NIEM so it is up to facilitator to serve as a mediator between business concepts and NIEM concepts. The result should be an agreed upon domain model that represents the business requirements while leveraging concepts set forth by NIEM. A precise and accurately defined domain model will result in more straightforward mapping.
Augmentation is a NIEM-specific methodology that allows for re-use of extensions that occur within a particular domain for use elsewhere. Augmentation does not implement ID and IDREF; instead it relies on element inclusion for associating the augmentation information to the base object, so essentially the augmentation becomes a property of the base object. Mapping to elements that exist in NIEM augmentation structures should not be any different than traditional mapping.