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					                                           Systems Engineering




Systems Architecting
             An introduction




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                                                   Systems Engineering



                   Agenda

• Evolution of Systems
• Relating Systems
  Engineering & Architectures
• Representing an Architecture
• Using Architectures
• Summary



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                                      Systems Engineering



Evolution of Systems




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                                      Systems Engineering



Evolution of Systems




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                                      Systems Engineering



Evolution of Systems




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                                                    Systems Engineering



         Evolution of Systems




Systems are becoming increasingly large and complex
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                                                     Systems Engineering



              No Easy Answer


Modern Systems:
 – Ill-Structured
 – Involve New & Untested
   Ideas
 – Complex




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                                                      Systems Engineering



  Overcoming these Problems
                                                    Maybe he doesn’t want
                                                    to be in charge of the
                                                    next customer review

How will we:
 – Manage uncertainty
 – Manage complexity
 – Manage technological
   change




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                                                   Systems Engineering



Systems Engineering: the Process
 A process that transforms an operational need or
 market opportunity into a system description to
 support detail design.

            •Requirements Analysis
            •Functional Analysis
            •Synthesis
            •Systems Analysis /
            Management
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                                                  Systems Engineering



Systems Architecture: a Product
The design team’s interpretation / implementation
of customer requirements communicated thru:

•System Usage Scenarios (i.e., Use Cases)
•Functional Components & Interrelationships
•Physical Subsystems & Interfaces
•Etc…



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                                                    Systems Engineering



Systems Architecting: a Methodology
 A Segment of the Systems Engineering Process
 Which Facilitates the Identification of:

                • System Elements
                • Relationships
                • Design Principles

  That Collectively Satisfy Customer Requirements
  and Meet User Needs.



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                                                                                                                 Systems Engineering


    Architecting in the Systems Engineering Process
Process                                                                                Goal/Mission               System Analysis
Inputs                      Requirements Analysis                                      Analysis/Validation        • Modeling & Simulation
• Stakeholder Inputs        • Analyze Missions and Environments                                                   • Trade Studies
      Operational          • Identify Functional Requirements                                                    • Effectiveness Analysis
                            • Define/Refine Performance and Design Constraints                     Functional
            Requirements
                            • Identify Quality Attributes                                         Architecture
      MOE’s
                            • Validate Requirements                                                 Analysis
      Environments
      Constraints
      Capability-Based                               Requirements Loop                                                 System
            Acquisition                                                                                                 Management
      Quality Attributes                                                                                               • Risk Management
      Interoperability                             Functional Analysis & Allocation
                                                                                                                        • Data Management
      COTS/GOTS/BOTS                               • Decompose to Next-Lower Level Functions                           • Configuration Management
      Re-Use and Legacy                            • Define/Refine Functional Interfaces (Internal/External)           • Progress Measurement
• Technology Base                                   • Define/Refine/Integrate Functional Architecture                         IMP/IMS & TPMs
• Prior Phase Results                               • Allocate Performance & Other Requirements                               Technical Reviews
• Applied Standards
                                                                                                                      Physical
                                                                                      Design Loop                     Architecture Analysis

                                          Verification Loop                         Synthesis
                                                                                    • Transform Each Level’s Architecture from Functional to Physical
                                                                                    • Define Alternative System Concepts & Configuration Items
                                                                                    • Define/Refine Physical Interfaces (Internal/External)
                                 Iteration Loop                                     • Identify Candidate Architecture Styles
                                 (Derived Requirements for the                      • Select “Best Value” Design
                                 Next Level of Decomposition)
                                                                                                  Process
                                                                                                  Outputs
                                                                                                  • “Best Value” System Architecture
                                                                                                  • System Architecture Models and Specifications
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    The Two Primary Methods of
           Architecting
• Structured Analysis and Design Technique (SADT)
   – Graphical Representation of System Requirements
     • Boxes and Arrows
     • Logical Flows

• Object-Oriented Analysis (OOA) and the Unified
  Modeling Language (UML)
  – Structure Diagrams
  – Behavior Diagrams
  – Interaction Diagrams


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                                                          Systems Engineering



Goals of Systems Architecting

• Take into account the whole picture
  – Life cycle phases, boundaries, external elements…
  – Users, builders, benefactors, supporters, environments
  – Affordability, safety, availability, survivability, security, etc.


• Communicate clearly the components and their
  inter-relationships from user and engineering
  perspectives
  – for customer validation
  – for use in analysis and design by all engineering disciplines



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                                                                   Systems Engineering



         Describing the Architecture


                                                            Physical Descriptions




Operational Expectations




                                            Behavioral
Many perspectives: physical, functional, operational,Descriptions
                                                       technical…
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                                                                        Systems Engineering


Physical View to an Architecture




                                                             Perspective View



      Plan View




  Front Elevation View
                                                              Building Codes
                                                          Technical Standards View
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              Functional View to an Architecture
                                        (Example Based on Unified Modeling Language)


                                                                                            Provide Human Habitat




                                                                Provide Nurishment                 Provide Protection                          Provide Comfort                                             Provide Communications &
                      Provide Space                                                                                                                                                                               Entertainment




                                                       Provide Food & Drink Provide Waste Disposal
                                                                                                                                   Provide Sleeping              Provide Seating    Provide Video Entertainment                                  Provide Telephony
Provide Access & Mobility       Provide Living Space
                                                                                                                                                                                                          Provide Audio Entertainment

                                                                                                                                                                                                                            Provide Computing Entertainment
                     Provide Storage                                                                                                         Provide Climate
                                                                                     Provide Physical Security Provide Physical Protection              Provide Personal Cleaning




    Provide Vehicle Storage      Provide Object Storage




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Product Diagrams of the Systems Architecture
                                                                                                                                                                                         Piloted Strike System                     Combat Air
                                                                                                                                                                                         & SoS Aggregations                      Operations Group
                                                                                                                                                                                         with System of System
                                                                                     Receive Solo Mission Start
                                                                                                                                                                                         Classes in green
Operation Commander                                                                          Clearance
                                                                    <<include>>                                   <<extend>> Taxi Solo to Taxi Hold-Point                                                      1                                                       0..n
                                                                         <<include>>
                                                                                                                                                                                                                                           1..n
              PSS Pilot                                                                   Taxi Solo to Point       <<extend>>                                                           Air Operations Commander                 Operation Group                  Mission Area Commander
                                                                       <<include>>

                                                                                                                     Taxi Solo to Take Off Hold-Point
 Air Traffic Controller                 Taxi/ Take Off Solo Air Vehicle      <<include>>
                                                                                        Perform Final Pre-Flight Tests                                                                                        1                           1..n
                                                                                                                                                                                              Operation
                                                                                                                                                                                                                                  Flight Package
                                                                                  <<include>>                                                                                                Commander

                                                                                            Take Off Solo Air Vehicle
                                                                           <<include>>
                                                                                                                                                                                                              1
                                         Land/ Taxi Solo Air Vehicle                                                                                                                                                                       1..n
                                                                                                                                                                                         Mission Commander                   Piloted Strike System
                                                                                   Enter Solo Flight Holding Pattern
                                                                        <<include>>


                                                                                                                                                                                                          1              1
                                                                                                                                                                                                                                   0..n             0..n
                                                              Enter Solo Landing Approach                                                                                                 PSS Pilot           PSS Air Vehicle         JDAM          Small Diameter Bomb



                                Use Case Diagrams
                                                                                                                                                                                                              Class Diagrams
                                      : Planning System                                      : PSS Pilot                                 : PSS Air Vehicle

                              Mission plan completed in                                                                          Air Vehicle powered up,
                              planning system, encrypted,                                                                        checked out and ready for
                              and ready for transfer                                                                             mission plan


                          Display menu for selecting method of                    Choose appropriate mission
                                                                                                                                                                                                                   : PSS Pilot                        : PSS Air                     : Airborne                       : Refueling
                          transfer of mission plan to Air Vehicle                    plan transfer method
                                                                                                                                                                                                                                                       Vehicle                        Tanker                          Specialist

                                                                                                                                                                                                  Visually Monitor                    Display Fuel Level,             Display Fueling                                       Initiate Fuel Flow
                                                                                                                                                                                                                                                                                               1: Flow Fuel to Air
                                                                                                                                                                                                  Tanking Operation,                  Report Fuel Level               Progress,                                             Through Fuel Boom
                                                                                                                                                                                                                                                                                            Vehicle(Initiate Fuel Flow :
                                            Radio mission plan to                                                                                    Radio receive                                Monitor Fuel Level                                                  Display Interlock
                                                                                                                                                                                                                                                                                                    Command)
                                                 Air Vehicle                                                                                         mission plan                                                                                                     Locked Status
                                                                                                                                                                                                                                                                                                                              Seq's 3, 7, and 8 are
                      Transfer mission plan to                                      Carry data transfer                                                                                                                                                                                    2: Update Fueling Progress         concurrent
                       data transfer cartridge                                    cartridge to Air Vehicle                                                                                                                                                                                  Display(Fuel Level : Data)

                                                                                    Put data transfer                             Receive data                                                                                                                                              3: Monitor Fueling Situation
                                                                                  cartridge in Air Vehicle                      transfer cartridge                                                                        4: Report Fueling Anomaly                                          Display(Fuel Level : Data,
                                                                                                                                                                                                                           Status(Anomaly Scene :                                         Fueling Operation Scene : View)
                                                                                                                                               Request                                                                    View, Anomaly Fuel Level
                                                                                                                                             decryption key                                                                      Data : Data)

                                                                                                                                                                 See Mission Plan &
                                                                                                                                                                                                                             5: Radio Relay Fueling
                                                                                                                                                                                                                                                            6: Audio Message Fueling
                                                                                                                                                                 Pilot Authentication                                        Anomaly Report(Verbal
                                                                                                                                                                                                                                                             Anomaly Report(Verbal
                                                                                                                                                                 Use Case                                                    Anomaly Report : Data)                                            7: Monitor for Fueling
                                                                                                                                                                                                                                                              Anomaly Report : Data)
                                                                                                                                                                                                                                                                                             Anomaly Reports(Verbal
                                                                                                                               Display confirmation of mission                                                                                                                                Anomaly Report : Data)
                                                                                                                                   plan & pilot acceptance
                                                                                                                                                                                                                                                                                           8: Automatically Monitor for
                                                                                                                                    Air Vehicle ready for                                                                                                                                        Fuel Level and
                                                                                                                                    taxi and operational                                                                                                                                         Emergencies( )
                                                                                                                                    use




                                       Activity & State Diagrams
                                                                                                                                                                                                                                    Sequence Diagrams
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                                                Systems Engineering


DoDAF – DoD Architecture Framework
     Customer Defined Views of the Model




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                                                                                      Systems Engineering


                     Operational View (OV)
               What needs to be done & Who does it




High Level Operational Concept Graphic (OV-1)                    Operational Exchange Matrix (OV-3)




Operational Node Connectivity Diagram (OV-2)                   Organizational Relationships Chart (OV-4)

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                                                                                            Systems Engineering


                               System View (SV)
Relates Systems and Characteristics to Operational Needs




        System Interface Description (SV-1)                               System – Systems Matrix (SV-3)




 System Functionality Description (SV-4) UML Version                 System Functionality Description (SV-4)

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                                                                                           Systems Engineering


                             Technical View (TV)
                   Prescribes Standards and Conventions




System Products Associated With Standards (TV – 1)
                                                                                Template for Time Records (TV-1)




                                        Technical Standards Profile Template (TV-1)

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                                                                                               Systems Engineering


                    25 Views Integrated Together
AV – 1 Overview & Summary Information
AV – 2 Integrated Dictionary
OV – 1 High Level Operational Concept
OV – 2 Op. Node Connectivity Description
OV – 3 Op. Informational Exchange Matrix
OV – 4 Org. Relationships Chart
OV – 5 Activity Model
OV – 6a Operational Rules
OV – 6b Operational State Transition
OV – 6c Op. Event Trace Description
OV – 7 Logical Data Mode
SV – 1 Systems Interface Description
SV – 2 Systems Communication Description
SV – 3 Systems Matrix
SV – 4 System Functionality Description
SV – 5 Op. Activity to Systems Function Traceability Matrix
SV – 6 System Data Exchange Matrix
SV – 7 System Performance Parameters
SV – 8 System Evolution Description
SV – 9 System Technology Forecast
SV – 10a System Rules Model
SV – 10b System State Transition Description
SV – 11 Physical Data Model
TV – 1 Technical Architecture Profile
TV – 2 Standards Technology Forecast                          Version 1.0 – October 18, 2005                   23
                                                           Systems Engineering


                   DoDAF Summary

DoDAF is a way of describing a
 system.
DoDAF represents a number of
 different views of the
 architecture.
DoDAF is a required output to our
 customers.

DoDAF is NOT a methodology or
 process.
DoDAF is NOT a UML based set
 of views.


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                                                    Systems Engineering



     Benefits of Architecting

•   Identifies All System Elements Earlier vs. Later
•   Matches Function to Requirements
•   Capture & Communicate Key concepts
•   Results in ONE design
•   Manages Increasing Complexity
•   Allows Modular Design




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                                                                             Systems Engineering


       Users of the Architecture
• Systems Architect: Translate Client Needs into Builder
  Requirements
• System Designers: Design Guidance
• Program Managers: Program Performance Measurement and
  Guidance
• Customers: Validation of Requirements and Design
• Other Stakeholders: Various Views of the System*
   – Manufacturers            - Trainers
   – Testers                  - Users
   – Purchasers               - Logistics Personnel
   – Handlers                 - Maintainers

        * Adapted from: Agile Systems Engineering Architecting: Methods, Processes, and Practices
                                                  Stevens Institute of Technology, March 15, 2004


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                                                        Systems Engineering


         Architecture Used In …
• Analysis of Alternatives (AoA)
• Business and Technical Planning
• Communications among Organizations
   – Internal to Internal
   – Internal to External
• Input to Subsequent System Design and Development
• Criteria for Certifying Conformance of Implementations
• Development, Maintenance, and Reuse Repositories
• Review, analysis, and evaluation of the system across the life
  cycle
• Basis for incremental/spiral development



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                                                      Systems Engineering


Characteristics of a Systems Architect
                                      •   Analytical
                                      •   Attention to Detail
                                      •   Visionary
                                      •   Generalist
                                      •   Common Sense
                                      •   Know-How
                                      •   Drive
                                      •   Critical Attitude
                                      •   Multi-tasking
                                      •   Teamwork
                                      •   Communicator/Documenter
                                      •   Flexible
                                      •   Process Insight
                                      •   Political Insight/Negotiation


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                                             Systems Engineering



The Risks of Architecting

                                  • Early Identification of
                                    Problems
                                  • Perception of Program
                                    Delay
                                  • Inconsistent Application
                                    of Methodologies
                                  • Limited Numbers of
                                    Skilled Creators/
                                    Reviewers

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                                                       Systems Engineering



      Risks of Not Architecting

• Late Identification of
  Problems
• Lack of Unified
  Design
• Issues of Complexity
  Management




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                                                              Systems Engineering



      Example Architecture Issues

Audi 2006 A8, A8 L, and A8 L W12 Passenger Vehicles
On certain passenger vehicles, a wiring harness condition exists that may
deactivate the passenger side frontal air bag even under circumstances when it
should remain activated.

Starbucks Coffee Company Recall of Ceramic Teapots
The teapots are labeled safe for microwave use, but the handles can become
hot in the microwave oven. This poses a possible burn hazard to consumers.

Microsoft Xbox 360 – Class Action Lawsuit
There may be a design flaw which causes the console's power supply and CPU
to overheat, causing the whole system to seize up. Complaints of similar
freezing problems began to surface almost as soon as the Xbox 360 went on
sale November 22.


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                                                     Systems Engineering



                   Summary

• Increasingly complex systems drive a need for better,
  clearer design descriptions
• Architectures convey the system designer’s
  interpretation of the requirements
• Architectures may be presented by a variety of views
  which collectively describe the system
• As part of the systems engineering process, systems
  architecting defines and manages development of a
  system


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                                 Systems Engineering




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                       References


• Boeing Systems Architecture Development Guidebook
• “The Art of Systems Architecting”, Eberhardt Rechtin, Mark W.
  Maier
• DoD Architecture Framework (DoDAF)




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                                             Systems Engineering


Recommended Use of DoDAF Products




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                                      Systems Engineering


DoDAF View Extraction




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                                                                                Systems Engineering


         Evolving Architectures: Impact of Spiral
                     Development
FY99-00 FY01 FY02 FY03 FY04 FY05 FY06 FY07 FY08 FY09 FY10 FY11 FY12 FY13
  Concept Demo

                                         Development
                                                                               Traditional
                                                                                           Production

   System Technology Demo
                         Fieldable Prototype Demo
                                                                          Collaborative
                                             OCA                             Spirals
                                                                      Production

Integrated
Acquisition                       Spiral 1 Development
   Team                                          OCA
 • Users                                                   Spiral 2
 • Acquirers                                                              OCA
 • Testers                                                                      Spiral 3
 • Researchers                                                                             OCA
 • Logisticians

Continuous User Assessment & Collaboration; Sustainment & CONOPS Refinement

OCA = Ops Capability Assessment             Spiral Definition / Requirements
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                                                             Systems Engineering



 Model-Based Architecture

Why Model-Based Architectures?
 – Help to Explain How Things Work
 – Broaden Our Perspective
 – Provide a Common Conceptual Frame of
   Reference
 – Express Rules More Simply
 – Clarify Relationships, Identify Key Elements, and
   Consciously Eliminate Confusion Factors

             From: Forsbert, Kevin; “Visualizing Project Management”, Pg. 14


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