1. Phase 3 The Software Requirements Specification

2. After review of the customer’s System Spec. After educated analysis Preliminary design A technical, software “approach” Results in permission to detail-design and code

3. Customer Points-of-Contention Assumptions, Constraints, Limits Function Documentation – technical, user, and training manuals Training Maintenance / Enhancements Requirements Changes Status and Reviews

4. From the customer’s perspective How smart people are going to solve the problem that was stated in the System Spec. A “contract”, more or less Is it doable? ◦ Technically ◦ On time ◦ Under budget

5. Settles these issues: Software Architecture – Object Oriented? – Structured? – Database Oriented (Informational Flow)? – Event Driven Major Modules – to 2 or 3 levels of supervision – low level utilities if they touch hardware or the environment

6. Risk Assessment Technical Risks ◦ hardware / software / interfaces ◦ build vs. buy ◦ team expertise needed Schedule Risks ◦ budget ◦ calendar ◦ personnel – level of expertise required

7. Phase 3 Write PARTS OF an SRS ◦ Architectural Drawings ◦ Main User Screen(s) ◦ Integration Thread (also a Drawing) ◦ Change of Scope Form ◦ Cross Reference Listing

8. What is a module? Outputs Inputs Storage Processing Simple Block Diagram Form Arrows, of course, should be labeled

9. Data Flow Diagram Data Conversion DFD Standard Shapes Arrows, of course, should be labeled Temporary Storage Sink Source

10. Air Traffic Control DisplayDatabaseRadar AddRemoveEdit Disk Access Display Refresh UI RecordPlayback Sweep Data Conversion Data Interpretation

11. City Simulator

12. Talking Head

13. Talker

14. Data Flow Diagram - shows movement, conversion, and storage of data This is the "top" drawing of a $6 million, 45-person, 1 million LOC, 4 year project

15. Cloud Chart - (pre UML) object relationships