EuSEC Tool Vendors Challenge Adie Ditchburn Jon Chard 19 Sep 2006

© Telelogic AB 2 Approach Discuss Method of Deriving Requirements –Structure –Role of Modelling Relationship of Models to requirements Demonstrate DOORS Structure –Database Level –Module Level Demonstrate Modelling using TAU –Use Case to System Level Activity Models –Logical System Structure Models Discuss Information Traceability Demonstrate Traceability in DOORS –Traceability Reports

© Telelogic AB 3 System Requirements Agree Requirements Qualification Strategy Analyze & Model Stakeholder Requirements Acceptance Strategy Agree Requirements System Models Analysis Results Derive Requirements & Qualification Strategy Deriving System Requirements

© Telelogic AB 4 Understanding your requirements Dont just list requirements, use structure to understand them Organise similar requirements into sections within documents Use structure to discover: –Context (overall situation in which the requirement occurs) Allows you to see the whole picture – Duplications (same requirement stated twice) Causes work to be performed twice Can lead to conflicting requirements Doubles your maintenance cost – Omissions (missing requirements) Unstated requirements become missing functionality Could cause shortcomings in non-functional areas such as performance, reliability, ease of use - that can not be re- engineered back into the system once developed

© Telelogic AB 5 Functional modeling Functional modeling Functional modeling Models Bridge Layers of Requirements Requirements layer Modeling layer Requirements layer Modeling layer Requirements layer Modeling layer Requirements layer e.g Goal / Usage modeling e.g. Functional modeling Sponsor Requirements Design Specification System Requirements Statement of need e.g. Performance modeling Concept: Requirements and Modeling

© Telelogic AB 6 Tool Vendor Challenge CCC Layers of Requirements and Models Challenge Statement Concept: Requirements and Modeling Stakeholder Requirements System Requirements Sub-System Requirements Constructed in DOORS Functional modeling Functional modeling Functional modeling Use Case modeling Activity modeling Functional modeling Constructed in TAU Implementation

© Telelogic AB 7 DOORS and TAU Demonstrations Demonstration of Requirements Structure in DOORS Demonstration of SysML Modelling in TAU Over to you Jon

© Telelogic AB 8 Requirements visualization and satisfaction through modelling in Tau with traceability to DOORS

© Telelogic AB 9 System black-box use cases in Tau SysML

© Telelogic AB 10 Example system block structure in Tau SysML

© Telelogic AB 11 Example configuration block internal structure diagram

© Telelogic AB 12 State machine description of subsystem block behaviour

© Telelogic AB 13 Information Traceability INFORMATION TRACEABILITY: Understanding how high-level objectives are transformed into low-level goals. e.g. in business terms: Understanding how business vision interpreted as business objectives implemented as business processes e.g. in systems engineering: Understanding how user requirements satisfied by system requirements implemented as design artifacts implemented as components

© Telelogic AB 14 Benefits of Information Traceability Greater confidence that objectives are being met. Ability to manage change through ability to access change impact. Greater accountability of subordinate organisations/suppliers. Ability to track progress / status particularly in the formative stages of project. Ability to deliver value through cost/benefit analysis.

© Telelogic AB 15 DOORS Demonstration Demonstration of Production of Traceability Reports Once again Jon

© Telelogic AB 16 Use of DOORS traceability analysis tools to show requirements satisfaction through SysML model.