SEDC 2014 Chantilly, VA 3-5 April 2014

1. SEDC 2014Chantilly, VA3-5 April 2014 A Hybrid Approach to Developing Enterprise Architecture Mr. Barry Masciale Space Systems Sector TASC, Inc. Chantilly, VA Dr. Warren K. Vaneman Department of Systems Engineering Naval Postgraduate School Monterey, CA Mr. Bruce Fenchel URS Federal Services Systems Engineering & Information Solutions Group Chantilly, VA

2. Enterprise Architecture Overview • A well-defined Enterprise Architecture (EA) represents the perspectives of the different stakeholders necessary to gain advocacy. It provides end-to-end traceability from stakeholder objectives, and desired capabilities, to the solution architecture. • Provides end-to-end traceability from stakeholder objectives, and desired capabilities, to the solution architecture • EAs artifacts reflect different levels of abstraction that logically progress from conceptual, to logical, to implementation, while maintaining concordance across the artifacts • Levels of abstraction are required to communicate to the diverse consumers of EA

3. Enterprise Architecture Overview • EAs are predominantly constructed using either Structured Analysis and Design Technique (SADT) or Object Oriented Analysis and Design (OOA&D) • While each technique has its own strengths and weaknesses, system and enterprise architects typically prefer to use only one of these analysis techniques, thereby not realizing the potential benefits of the other A hybrid approach capitalizes on the strengths of both SADT and OOA&D

4. SADT & OOA&D • Structured Analysis and Design Technique (SADT) provides a top-down, holistic, technique that focuses on the totality of the Enterprise where functionality is “mutually exclusive”, non-overlapping, functionality, and can be “totally exhaustive,” encompasses the entire scope • Object Oriented Analysis and Design (OOA&D) relies predominantly on a goal-oriented threads-based technique that is well-suited to identify the perspective of individual stakeholders and express how each thread relates to the enterprise

5. Characteristics of EA Development Approaches

6. Why a Hybrid Approach? • A hybrid methodology leverages top-down, holistic, systematic, development techniques of SADT with the adaptability of OOA&D to create an architecture that offers the best of both worlds • Provides meaningful artifacts that represent stakeholder’s perspectives necessary to support decisions in the context of the enterprise • Incorporate changes by modifying the most effective points in the models, and then verify against the other models • Modify holistic model with new functionality and update threads • Modify a thread and integrate into the holistic model + =

7. Partial Metamodel

8. Hybrid Approach Steps

9. Hybrid Approach StepsStep 1: Planning the Architecture • Identify the stakeholders and their business needs (objectives) using their terminology • Interpret business needs in terms of high level functions (capabilities) • Develop key Use Cases to describe how capabilities interact to satisfy business needs • Identify high-level program risks and mitigation strategy • Define scope, purpose, and viewpoint to influence functional decomposition (described in Step 3) • Important discriminator between a reference model and an architecture • Select Architecture Framework (e.g., DoDAF, FEAF, TOGAF, MODAF, Zachman) and methodology • Begin integrated dictionary and continue to update throughout the EA development

10. Hybrid Approach StepsStep 2: Develop Architecture Artifacts • Define the enterprise boundary • Understand the interactions of the enterprise with the external environment • Define what the enterprise provides • Define what the enterprise needs • Define the enterprise level transactions • Provides an executive-level product of boundary architecture information to ensure that the enterprise “customers” and stakeholders have their needs satisfied

11. Hybrid Approach StepsStep 3: Model Internal EA • Decompose data consumed and produced by functions (or activities) • Decompose functions to a level that supports allocation (e.g., system, component, service, human) • Approach leverages perspectives of SADT functional decomposition and Use Case analysis • Technique informs each other • Allocate functions to services, systems and people • Identify classes from the Use Cases and are organize into logically groupings • Derive classes from architecture data and other elements

12. Hybrid Approach StepsStep 4: Derive Behavioral Models and Sequence Diagrams • Construct activity diagrams from Use Cases or mission threads • Refine classes using derived activities as operations • Deployment diagram will show how classes and services will be realized • Develop sequence diagrams to depict how services will interact • Create behavioral models • Reflect constraints • Derive requirements from the functional decomposition

13. Hybrid Approach StepsStep 5: Analyze EA Using Executable Models • Convert static architectural data to dynamic architectural data by adding timing or performance parameters • Run executable model to verify the logic of the architecture, and determine a coarse level of architectural performance • Use the operational deployment provide insight into the transition strategy/roadmap • Shows transition of target EA from the “As-Is” to the planned “To-Be” to the desired “Should-be”

14. Hybrid Artifacts SADT Artifacts OOA&D Artifacts Concept of Operations Integrated Dictionary Service Component Model Class Diagram Data Model Resource Flow Matrix Use Cases Inventory Diagram Rules Models Deployment Diagram Activity Diagrams State Transition Diagram Executable Model • Concept of Operations • Integrated Dictionary • External Functional Decomposition • Internal Functional Decomposition • Architecturally Derived Requirements • Service Identification • Rules Models • Enhanced Functional Flow Block Diagrams

15. Summary • A hybrid methodology leverages top-down, holistic, systematic, development techniques of SADT with the adaptability of OOA&D to create an architecture that offers the best of both worlds • A bridge is formed among stakeholders, system architects, system engineers, developers, and system integrators • The hybrid enterprise architecture approach presented today is extensible and must be tailored to meet unique project needs

16. Questions

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