1. CS 501: Software Engineering Fall 199 Lecture 1 a) Administration b) Introduction to Software Engineering

2. Course Administration Web site: www.cs.cornell.edu/cs501-fa99 Instructor: William Arms Teaching assistant: Nate Nystrom Assistant: Rosemary Adessa Text book: Software Engineering, Fifth Edition, by Ian Sommerville (Addison-Wesley), 1996. Computer lab: Computer Science Undergraduate Lab, Upson Hall, Room 315/317.

3. Code of Conduct  Software Engineering is a collaborative activity. You are encouraged to work together, but...  Some tasks may require individual work.  Always give credit to your sources and collaborators. Good professional practice: To make use of the expertise of others and to build on previous work, with proper attribution. Unethical and academic plagiarism: To use the efforts of others without attribution.

4. Projects  Project teams, about 5 people.  Select your own project, any branch of software engineering  Real project for real client who intends to use the software in production.  Project plan: September 9  Progress report: October 14  Final presentation: End of term (dates to be announced)  Seminars on Friday to suggest projects

5. Course Themes 1. Leadership of large software projects  Software as a product Clients and their needs Quality  Requirements and specification Usability Evolution  Project management Personnel management Economic, legal, and social factors

6. Course Themes 2. Large and very large program codes  Software design Software architecture Object-oriented design  Dependable systems Reliability Verification  Computer-aided software engineering  Legacy systems

7. Characteristics of Software Products Sommerville's list Usability Maintainability Dependability Efficiency Good software products require good programming, but... Programming quality is the means to the end, not the end itself. Example: DEC's optical scanner

8. Previous Experience Your background  Biggest program that you have written?  Biggest program that you have worked on?  Biggest project team that you have been part of?  Longest project that you have worked on?  Most people who have used your work?  Longest that your project has been in production? My background

9. Future Experience What will you be doing one year from now? Ten years from now?

10. Software as a Product Software is expensive!! Every software project has a trade-off between: Function Resources Timeliness Example: Andrew console monitor

11. Client (a.k.a Customer)  The client provides resources and expects some product in return.  Client satisfaction is the primary measurement of success. Question: Who is the client for Microsoft Excel?

12. Professional Responsibility Organizations put trust in software developers:  Competence: Software that does not work effectively can destroy an organization.  Confidentiality: Software developers and systems administrators may have access to highly confidential information (e.g., trade secrets, personal data).  Legal environment: Software exists in a complex legal environment (e.g., intellectual property, obscenity).  Acceptable use and misuse: Computer abuse can paralyze an organization (e.g., the Internet worm).

13. Variety of Software Products Examples?

14. Categories of Product Categories of client and software product:  Generic (e.g., Microsoft Excel)  Bespoke (customized) (e.g., IRS internal system) Many systems are customized versions of generic packages (e.g., Cornell's payroll system)

15. Variety of Software Products Software products are very varied --> Client requirements are very different --> There is no standard process for software engineering --> There is no best language, operating system, platform, database system, development environment, etc. A skilled software developer knows about a wide variety of approaches, methods, tools. The craft of software engineering is to select appropriate methods for each project and apply them effectively.

16. Reading Before next class, read and be ready to discuss: Sommerville: Chapters 1, 2 and 3 pages 1 to 59. Pay particular attention to the discussion of the Software Process, beginning on page 7.