More Agile than Agile SEDC 2014 April 5, 2014 Zane Scott, VP for Professional Services Vitech Corporation

2 THESIS: A layered approach to model-based systems engineering promotes the concepts and principles of agile development and is arguably even MORE AGILE THAN AGILE!

The Agile Manifesto Individuals and interactions over processes and tools Working software over comprehensive documentation Customer collaboration over contract negotiation Responding to change over following a plan Vitech Corporation3

The Agile Manifesto Individuals and interactions over processes and tools Working solutions over comprehensive documentation Customer collaboration over contract negotiation Responding to change over following a plan Vitech Corporation4

Agile Principles Our highest priority is to satisfy the customer through early and continuous delivery of valuable software. Welcome changing requirements, even late in development. Agile processes harness change for the customer's competitive advantage. Deliver working software frequently, from a couple of weeks to a couple of months, with a preference to the shorter timescale. Business people and developers must work together daily throughout the project. Build projects around motivated individuals. Give them the environment and support they need, and trust them to get the job done. The most efficient and effective method of conveying information to and within a development team is face-to-face conversation. Working software is the primary measure of progress. Agile processes promote sustainable development. The sponsors, developers, and users should be able to maintain a constant pace indefinitely. Continuous attention to technical excellence and good design enhances agility. Simplicity--the art of maximizing the amount of work not done--is essential. The best architectures, requirements, and designs emerge from self-organizing teams. At regular intervals, the team reflects on how to become more effective, then tunes and adjusts its behavior accordingly Vitech Corporation5

Agile Principles Our highest priority is to satisfy the customer through early and continuous delivery of valuable software. Welcome changing requirements, even late in development. Agile processes harness change for the customer's competitive advantage. Deliver working software frequently, from a couple of weeks to a couple of months, with a preference to the shorter timescale. Business people and developers must work together daily throughout the project. Build projects around motivated individuals. Give them the environment and support they need, and trust them to get the job done. The most efficient and effective method of conveying information to and within a development team is face-to-face conversation. Working software is the primary measure of progress. Agile processes promote sustainable development. The sponsors, developers, and users should be able to maintain a constant pace indefinitely. Continuous attention to technical excellence and good design enhances agility. Simplicity--the art of maximizing the amount of work not done--is essential. The best architectures, requirements, and designs emerge from self-organizing teams. At regular intervals, the team reflects on how to become more effective, then tunes and adjusts its behavior accordingly Vitech Corporation6

Principles Our highest priority is to satisfy the customer We welcome changing requirements Deliver working solutions frequently. Stakeholders and solution designers must work together daily Build projects around motivated individuals. Give them the environment and support they need, and trust them to get the job done. Working solutions are the primary measure of progress. Agile processes promote sustainable development. The sponsors, developers, and users should be able to maintain a constant pace indefinitely. Continuous attention to technical excellence and good design enhances agility. Simplicity--the art of maximizing the amount of work not done--is essential. Vitech Corporation7

WHAT IS LAYERED MBSE? Vitech Corporation8

Begin High Innovation Vision Alternatives Vitech Corporation9

Innovation Inspiration Ideation Validation Number of Prototypes Time Spent Developing Prototypes

Vision Vitech Corporation11

Vision Vitech Corporation12

Alternatives Vitech Corporation13 Q

Alternatives Vitech Corporation14 Q

Alternatives Vitech Corporation15 Q

What about middle-out? Vitech Corporation16 EXCURSUS Get high!

MBSE Activities Timeline – Top Down Activity bars represent movement of “center of gravity” of systems engineering team. Concurrent engineering is assumed. 5. Derive Integrated System Behavior 6. Derive Component Hierarchy 0. Define Need & System Concept 1.Capture & Analyze Orig. Requirements 2. Define System Boundary 4. Derive System Threads 3.Capture Originating Architecture Constraints 8. Define Internal Interfaces 11. Define Resources, Error Detection, & Recovery Behavior 12. Develop Validation Requirements/Validation Plans 9. Select Design 13. Generate Documentation and Specifications 7. Allocate Behavior to Components 10. Perform Effectiveness & Feasibility Analyses SCHEDULE Vitech Corporation17

MBSE Timeline – Reverse/Middle Out 7.Derive As-Built System Requirements 1. Define System Boundary 5. Aggregate to As-Built System Behavior 4.Derive As-Built Behavior of Components 3.Capture Component Hierarchy 2. Capture Interfaces 6.Derive As-Built System Threads 11. Capture Error Detection, Resource, & Recovery Behavior 12. Develop Test Plans 9. Select Design 13. Generate Documentation and Specifications 10. Perform Effectiveness & Feasibility Analyses 6a.Modify System Threads 5a.Modify & Decompose System Behavior 4a.Allocate Behavior to Components 3a.Refine Component Hierarchy 2a. Define Interfaces Find the top, Then modify top-down. 7a.Modify Reqts & Arch. Constraints 8. Update System Boundary SCHEDULE Vitech Corporation18

Work In All 4 Domains Don’t forget Eliminate rework Vitech Corporation19

Work In All 4 Domains Vitech Corporation20 All four domains At every layer

It’s All About Relationships Vitech Corporation21 basis of based on allocated to performs Requirements Behavior Components Requirements are the basis of Behavior Behavior is allocated to Components Behavior is based on Requirements Components perform Behavior Verify and Validate

Advance Granularity Orderly decisions Completeness at every layer Vitech Corporation22

Increasing Granularity Vitech Corporation23 REQ BEH ARCH Dgn V&V REQ BEH ARCH Dgn V&V Layer Of Detail Source Documents Docs REQ BEH ARCH Dgn V&V Docs LAYER LAYER 1 LAYER 2 LAYER n

SOME ISSUES AROUND MODELS Vitech Corporation24

What is a Model? What is NOT a model? What is a model? Vitech Corporation25

Views Are NOT a Model Views flow from the model 26 Vitech Corporation

What is a View? A structured answer to a request for a particular subset of information from the model 27 Vitech Corporation

What is a View? 28 Vitech Corporation query answer Model

What is a View? 29 Vitech Corporation query answer Model

Many Models? NO! Vitech Corporation30 Requirements Behavior Architecture Testing

Power in the Interactions Vitech Corporation31 Behavior Architecture Testing Requirements MODEL

Vitech Corporation32 As Designed As Reported As Heard As Tested The Testing Problem

Models in MBSE Models – Are limited representations of a system or process – Can be migrated into a cohesive unambiguous representation of a system In model-based systems engineering – The ‘model’ is the system specification; conversely the system specification is the model – The visualizations are derived from the model – The model rests on the logical architecture (function) Vitech Corporation33

MBSE MEETS AGILE Vitech Corporation34

Principle 1 The customer is key Validation at every layer Traceability Vitech Corporation35 Highest priority = satisfy the customer

Full Traceability (Bi-directional) Vitech Corporation REQUIREMENT: The system shall provide previously collected images/products, if appropriate. FUNCTION: The system shall provide previously collected images/products, if appropriate. IS THE BASIS OF IS ALLOCATED TO IS BASED ON PERFORMS ARCHITECTURE 36

Principle 2 Changing requirements don’t disrupt the orderly layer-to-layer transitions Model holds everything in relationship Vitech Corporation37 Welcome changing requirements

Change Model Vitech Corporation38 Requirements V & V Physical Architecure Behavior

Principle 3 The end result of each layer is a complete model Vitech Corporation39 Deliver working solutions frequently

Increasing Granularity Vitech Corporation40 REQ BEH ARCH Dgn V&V REQ BEH ARCH Dgn V&V Layer Of Detail Source Documents Docs REQ BEH ARCH Dgn V&V Docs LAYER LAYER 1 LAYER 2 LAYER n

Principle 4 By surfacing the model everyone can see it Choosing the appropriate view Vitech Corporation41 Stakeholders and designers work together

42 Who are they and what will speak to them? What do they need (want) to know? What do we need them to know? Vitech Corporation Which View?

Principle 5 Teams can collaborate in real time Model provides the discipline Team focuses on problem solving Vitech Corporation43 Give teams needed environment & support MODEL

Principle 6 Verify and validate at every layer Vitech Corporation44 Measure of progress is working solutions Requirements Behavior ComponentsRequirements Behavior Components V&V

Principle 7 Work is orderly Model manages complexity Problem does not become overwhelming Vitech Corporation45 Maintain a constant, supportable pace

Consistency Vitech Corporation46 Independent drawings v. Consistent views MODEL

Principle 8 Model insures integrity and completeness Design decision are intentional Vitech Corporation47 Technical excellence & good design

One Integrated Model Vitech Corporation48 Data verified by Source Requirements Domain Architecture Domain Behavior Domain V&V Domain verified by Originating requirements trace to behavior Originating requirements trace to physical components Behavior is allocated to physical components verified by c Data

Principle 9 Because views and documentation are generated by querying the model there is no need for repetitious clerical work Pieces of the model can be reused Vitech Corporation49 Maximize the amount of work not done

Vitech Corporation50

MANIFESTO VALUES Vitech Corporation51

Values Model focuses the work on design tasks instead of repetition and documentation work Engineers are freed to be engineers Communication is enhanced Vitech Corporation52 Individuals and interactions

Values Focus is problem solving- not drawing views or creating documents Vitech Corporation53 Working solutions

Values Views can be generated that: – Show the state of the model in real time – Are tailored to the audience Vitech Corporation54 Customer collaboration

Values Model holds everything in relationship Impact of change is immediately traceable Vitech Corporation55 Responding to change

SUMMARY Vitech Corporation56

MBSE Benefits to the Enterprise Enhanced communication – Shared understanding – Rich representations Reduced development risk – Early identification of requirements issues – Faster requirements cycle – Improved cost estimates – Early/on-going requirements validation & design verification – Disciplined basis for decision making Vitech Corporation57

Improved quality – Enhanced system design integrity – Improved specification of allocated requirements to HW/SW – Fewer errors during integration and test – More rigorous traceability from need through solution Increased productivity – Improved impact analysis of requirements changes – Rapid analysis of design changes – Reuse of existing models to support design/technology evolution – Auto-generation of work products Vitech Corporation58 MBSE Benefits to the Enterprise

Increased scope – Incorporation of domains – Integration of models – Extension of representations and audiences Provides a structure to capture and communicate all aspects of the system Vitech Corporation59

Thank You! For additional information: Zane Scott Vitech Corporation 2270 Kraft Drive, Suite 1600 Blacksburg, VA, 24060, USA Vitech Corporation60