Tonight s Agenda. CSC340: Requirements Engineering. Course Objectives. Requirements Engineering. Software Engineering. What is Software Engineering?

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1 Tonight s Agenda CSC340: Engineering Jennifer Campbell Lecturer Part 1 Introduction to course content Course information Changes to the SE courses/program Part 2 What are requirements? CSC340 University of Toronto 2 Engineering Theory, tools and techniques of problem analysis for software systems development, covering both information systems and control systems. Topics include: requirements specification, object-oriented analysis, business process modeling, and analysis of nonfunctional requirements. Course Objectives Examine the state-of-the-art for research & practice in Engineering. Gain practical experience in selected RE techniques. Understand the essential nature of RE. No design, no programming CSC340 University of Toronto 3 CSC340 University of Toronto 4 What is Software Engineering? The application of a systematic, disciplined, quantifiable approach to the development, operation, and maintenance of software. [IEEE93] Software Engineering Waterfall Model (out-of-date view of SE) CSC340 University of Toronto 5 CSC340 University of Toronto 6

2 Not a phase or stage! Communication is as important as the analysis Quality means fitness-forpurpose. Cannot say anything about quality unless you understand the purpose Definition of RE Engineering (RE) is a set of activities concerned with identifying and communicating the purpose of a software-intensive system, and the contexts in which it will be used. Hence, RE acts as the bridge between the real world needs of users, customers, and other constituencies affected by a software system, and the capabilities and opportunities afforded by softwareintensive technologies Need to identify all the stakeholders - not just the customer and user Designers need to know how and where the system will be used are partly about what is needed and partly about what is possible CSC340 University of Toronto 7 Boundaries Stakeholders Scenarios Feasibility, Risk Identifying the problem Which problem needs to be solved? Where is the problem? Whose problem is it? Why does it need solving? How might a software system help? When does it need solving? What might prevent us from solving it? Problem Domain Stakeholders Goals Development Constraints CSC340 University of Toronto 8 Why is RE challenging? It involves software-intensive systems. Software + hardware = computer system A computer-system on it s own is useless. Software + hardware + human activities = software-intensive system A new computer system will change human activities in significant ways. The goal is to write quality software. Quality = fitness for purpose Quality = Fitness for purpose A requirement is: A condition or capability that must be met by the system to solve a problem or achieve an objective. (IEEE 1984 quoted in [Bra02]) Software is designed for a purpose If software doesn t work well then either: the designer didn t have an adequate understanding of the purpose or we are using the software for a purpose different from the intended one analysis is about identifying this purpose Inadequate understanding of the purpose leads to poor quality software CSC340 University of Toronto 9 CSC340 University of Toronto 10 Quality = Fitness for purpose [2] The purpose is found in human activities E.g. Purpose of a banking system comes from the business activities of banks and the needs of their customers The purpose is often complex: Many different kinds of people and activities Conflicting interests among them Course Information Lecture notes will be posted the day before each lecture. Tutorial notes will be posted after each tutorial session (only the problem will be posted, not the solution) Readings will be posted each week CSC340 University of Toronto 11 CSC340 University of Toronto 12

3 Course work 1 individual assignment (3%) 4 team assignments (42%) Midterm test (20%) Final exam (35%) You must obtain at least 40% on the final exam to pass the course. Assignment 0 Describe a business process or device. Completed individually 2 page written assignment Due Tuesday, January 23 rd by 10am CSC340 University of Toronto 13 CSC340 University of Toronto 14 Team Work Teams are made up of four students. Teams will be formed by your instructor. For each assignment: You will complete a peer evaluation of each team member, as well as of yourself. Your assignment will be given a team mark, and your assignment mark will be adjusted based on your individual evaluation. You ll meet your team in tutorial next week. Assignment 1: Inspection (10%) Select one of the given requirements specifications. Conduct a formal inspection of that requirements specification. Report on defects found, overall quality of the specification, and inspection stats. CSC340 University of Toronto 15 CSC340 University of Toronto 16 Assignment 2: Feasibility (10%) You will be given a problem description. Perform a feasibility study for that problem. Propose several alternatives, analyze the feasibility and risk of each, and make a recommendation for how to proceed. Assignment 3: Modelling (10%) Analyze the problem given for Assignment 2. Model the problem using several modelling techniques. CSC340 University of Toronto 17 CSC340 University of Toronto 18

4 Assignment 4: Specification (12%) Build on the modelling work that you did in assignment 3. Write a requirements specification (includes identifying, tracing and validating requirements). How to succeed in CSC340? Make sure that you have the prerequisites Attend lectures and tutorials Work effectively in your groups This will impact your mark. Understand all parts of the assignment you hand it. You are responsible for all parts of the report (not just the section you wrote). CSC340 University of Toronto 19 CSC340 University of Toronto 20 Weeks 1-5 Intro What are? What is Engineering? What is a System? Specifications Formal Inspections Feasibility Studies Stakeholders Goals Elicitation Techniques Risk Course Outline Weeks 6-9 Intro to Modelling Enterprises Objects Relationships State Events Interactions Weeks Non-functional Verification and Validation Prioritizing Software Evolution Moving into Design Software Architectures CSC340 University of Toronto 21 Summary This course is different from most CS courses It is not about how to solve problems using computers It is about how to identify problems worth solving Comments from students in previous years vary dramatically: Some students really enjoy the course other students wish they were programming! CSC340 University of Toronto 22 Acknowledgement Thanks to Professor Steve Easterbrook for allowing me to adapt his lecture notes for this course. Changes to SE Courses/Program Starting in Fall 2007: Bye-bye: CSC 340, 407, 408 Hello: CSC 301 and 302 (Winter 2007 is the last semester that 340, 407 & 408 will be offered at St. George.) CSC340 University of Toronto 23 CSC340 University of Toronto 24

5 CSC301 & CSC302 CSC301H1 Introduction to Software Engineering An introduction to agile development methods appropriate for medium-sized teams and rapidly-moving projects. Basic software development infrastructure; requirements elicitation and tracking; estimation and prioritization; teamwork skills; basic UML; design patterns and refactoring; security, discussion of ethical issues, and professional responsibility. Prerequisite: CSC209H1, CSC263H1. CSC302H1 Engineering Large Software Systems An introduction to the theory and practice of large-scale software system design, development, and deployment. Project management; advanced UML; reverse engineering; requirements inspection; verification and validation; software architecture; performance modeling and analysis. Prerequisite: CSC301H1. Q&A Q: If I take CSC340 in Winter 2007, then what would I take in 07-08? A: Instead of 407 & 408, you would take 301 & 302. Q: If I wait and take 301 and 302 next year, can I complete the SE program without taking 340? A: Yes, you can take 301 & 302 instead of 340, 407 & 408. NOTE: You need to make sure that you take enough 4 th year courses to fulfill your degree requirements. CSC340 University of Toronto 25 CSC340 University of Toronto 26