Department of Defense Architecture Framework - Meta-model

Meta-model

DoDAF has a meta-model underpinning the framework, defining the types of modelling elements that can be used in each view and the relationships between them. DoDAF versions 1.0 thru 1.5 used the CADM meta-model, which was defined in IDEF1X (then later in UML) with an XML Schema derived from the resulting relational database. From version 2.0, DoDAF has adopted the IDEAS Group foundation ontology as the basis for its new meta-model. This new meta-model is called "DM2"; an acronym for "DoDAF Meta-Model". Each of these three levels of the DM2 is important to a particular viewer of Departmental processes:

1. The conceptual level or Conceptual Data Model (CDM) defines the high-level data constructs from which Architectural Descriptions are created in non-technical terms, so that executives and managers at all levels can understand the data basis of Architectural Description. Represented in the DoDAF V2.0 DIV-1 Viewpoint.
2. The Logical Data Model (LDM) adds technical information, such as attributes to the CDM and, when necessary, clarifies relationships into an unambiguous usage definition. Represented in the DoDAF V2.0 DIV-2 Viewpoint.
3. The Physical Exchange Specification (PES) consists of the LDM with general data types specified and implementation attributes (e.g., source, date) added, and then generated as an XSD. Represented in the DoDAF V2.0 DIV-3 Viewpoint.

The purposes of the DM2 are:

1. Establish and define the constrained vocabulary for description and discourse about DoDAF models (formerly “products”) and their usage in the 6 core processes
2. Specify the semantics and format for federated EA data exchange between:architecture development and analysis tools and architecture databases across the DoD Enterprise Architecture (EA) Community of Interest (COI) and with other authoritative data sources
3. Support discovery and understandability of EA data:
   1. Discovery of EA data using DM2 categories of information
   2. Understandability of EA data using DM2’s precise semantics augmented with linguistic traceability (aliases)
4. Provide a basis for semantic precision in architectural descriptions to support heterogeneous architectural description integration and analysis in support of core process decision making.

The DM2 defines architectural data elements and enables the integration and federation of Architectural Descriptions. It establishes a basis for semantic (i.e., understanding) consistency within and across Architectural Descriptions. In this manner, the DM2 supports the exchange and reuse of architectural information among JCAs, Components, and Federal and Coalition partners, thus facilitating the understanding and implementation of interoperability of processes and systems. As the DM2 matures to meet the ongoing data requirements of process owners, decision makers, architects, and new technologies, it will to a resource that more completely supports the requirements for architectural data, published in a consistently understandable way, and will enable greater ease for discovering, sharing, and reusing architectural data across organizational boundaries.

To facilitate the use of information at the data layer, the DoDAF describes a set of models for visualizing data through graphic, tabular, or textual means. These views relate to stakeholder requirements for producing an Architectural Description.