In a push to improve the interoperability of the complex systems that support joint-service and multinational operations–the ability for these systems to interact and share data–the Department of Defense created the Department of Defense Architecture Framework (DoDAF). The framework uses an architecture data model and repository system to establish a common approach and backbone for DoD architecture description development, presentation, and integration.
The effectiveness of the framework, however, has been hampered by the lack of semantic definitions, a methodology, and software tools to support valid, interoperable views, products, and reusable artifacts among the DoD’s operations processes. KBSI, in a project sponsored by the U.S. Air Force, designed, developed, and deployed a language, suite of tools, and methodology that enable true interoperability among the DoDAF’s complex joint-service and multinational operations support systems and technologies.
A comprehensive approach to systems interaction
There were historically a hodge-podge of tools and formats geared towards developing graphic, tabular, and textual artifacts for DoDAF modeling. These artifacts, however, are not “interoperability friendly”: they cannot be analyzed, verified, validated, queried, browsed, and shared with other tools and applications, severely limiting their utility. The most advanced capability that many low-end “DoDAF compliant” software tools currently provide is the ability to document the enterprise architecture–the tools do not facilitate model-based architecture analysis, a capability fundamental to improving enterprise efficiency. Recent moves to certify enterprise architecture software that provides syntactic interoperability–a common file format, for example–are a step forward, but miss the capability that true interoperability requires: semantic interoperability, or the structured manner in which system interaction occurs.
KBSI’s Framework for the Interoperability of Executable Architectures (FIEA) project bridged the gaps among DoDAF capable tools by defining the artifacts and products of a DoDAF architecture and defining the mathematical model that supports their execution for down-stream analysis, validation, and verification. FIEA developed the language and tools to support, first, model execution, ensuring that operations models are sufficiently detailed to allow verification, validation by the domain expert, and logical transformation into another architectural segment. FIEA also enables the management of executable models, ensuring that executable models yield measures of performance and effectiveness, including performance, fault-tolerance, availability, and security, for the various attributes of defense-related, mission-critical operations and systems.
The FIEA technology was developed by researchers from the Air Force Research Laboratory (AFRL), Electronic Systems Center (ESC), and KBSI, funded by an Air Force Small Business Innovative Research (SBIR) program. FIEA generates abstract executable models from basic enterprise architectures such as the DoD Architecture Framework (DoDAF) and the Federal Enterprise Architecture Framework (FEAF). These abstract models can be structurally derived from enterprise architectures to which executable content can be added. Once the model is encoded in an abstract executable model language called the Executable Architecture Representation Language (EARL), numerous downstream executions, including simulation-based analysis, quantitative analysis (e.g., using queuing theory) and service-oriented architecture (SOA) deployment, can be generated automatically. This “capture once, use often” concept allows for vendor-independent model reuse across a number of executable applications without having to change the core enterprise architecture.
The FIEA approach contrasts with approaches that require the modification of the core enterprise architecture meta-model to generate executable enterprise architecture models. The EARL supports the representation of executable content outside of the core enterprise architecture. The approach exploits the full potential of the core enterprise architecture: i.e., to emulate or simulate the system that is being modeled or to auto-generate code that automates an enterprise process. An example of the latter is the generation of Service Oriented Architecture (SOA)-based Web Services – Business Process Execution Language (WS-BPEL) or Web Services Choreography Description Language (WS-CDL).
The FIEA approach of developing executable architectures from enterprise architecture models using multiple layers of abstraction is effective for a number of reasons:
- models can be inspected at various levels to ensure correctness;
- models can be reused to generate different types of executions; and
- the traceability of results along multiple levels of abstraction provides for better documentation of results and better visibility into simulation results against requirements comparisons.
The FIEA-based executable architecture language support, translators and execution support tools have been integrated into KBSI’s ModelMosaic® modeling suite. FIEA technology transition activities include installation at the AFRL/RYT nucleus lab, layered sensing architecture modeling verification and validation, and missile defense planning interoperability demonstrations with the Missile Defense Agency.