Software Engineering Course Overview

Software Engineering Course Information

• Course instructor: Dr. Fatma ElSayed
• Department: Computer Science Department
• Email: [email protected]
• Academic year: 2024/2025

Course Contents

• Introduction to Software Engineering
• Software Processes
• Requirements Engineering
• System Design
• System Modeling
• System Architecture
• Software Testing Strategies
• Software Testing Techniques
• Technical Metrics for Software

What is Software?

• Computer programs and associated documentation.
• Includes documentation for setup, use, and user support materials.
• Intended to support professional software development, not individual programming
• Typically developed by teams rather than individuals
• Maintained and changed throughout its lifecycle

Attributes of Good Software

• Deliver required functionality and performance to the user
• Four essential attributes:
  • Maintainability: Meeting changing needs, easy upgrades, quick and cheap
  • Dependability: Trustworthy, no physical or economic damage
  • Efficiency: No wasteful resource use, minimized processor usage
  • Acceptability: Understandable, usable, and compatible with other systems, accepted by users

What is Software Engineering?

• Engineering discipline concerned with all aspects of software production using systematic, well-defined scientific techniques.
• Aims to produce an effective and reliable product.
• Engineers use a systematic approach, appropriate tools and techniques based on problem, constraints, resources
• Applies computer technology to everyday processes

Software Engineer vs Software Developer

• Software Developer: Builds software across various computer types; primarily solitary; writes complete programs; uses ready-made tools; limited scale
• Software Engineer: Applies software engineering principles for designing, developing, maintaining, and testing; team activity; works with hardware; creates development tools; larger scale problems

Software Engineering vs. System Engineering & Computer Science

• System Engineering: Concerned with all system aspects (hardware, software, human work, and procedures) needed to fulfill a mission. Software engineering is a part of this process, focusing on software development.
• Computer Science: Focuses on theory and fundamentals (programming languages, graphics, AI, machine learning). Software engineering focuses on practical applications and delivering usable software, using the scientific foundation of computer science.

Software Products

• Software systems delivered to a customer with documentation for installation and use.
• Generic Products: Stand-alone systems produced by a development organization and sold to any customer. Examples include databases, word processors, and project management tools.
• Customized Products: Systems specially built for a particular customer. Examples include business process systems, university admissions systems, and control systems for devices.

Difference between Generic and Customized Software

• Functionality: Generic has broad functionality for multiple users; customized is tailored to a specific problem or entity
• Specifications: Generic is internally developed; customized is negotiated between client and developer
• Quality: Quality is a major criterion for customized software; generic quality isn't as critical a driver
• Number of Users: Generic is many; custom may be limited to one entity
• Marketing: Generic requires marketing efforts, customized needs a contract
• Needs and Updates: Generic is defined by market, customized by client needs
• Development Cost: Generic costs are usually lower; customized is variable

Software Process

• Sequence of activities for producing software
• Different systems need different processes.
• Four fundamental activities:
  • Specification
  • Development (Design, Implementation)
  • Validation
  • Evolution

Software Process: Activities

• Specification: Defines what the software should do and its constraints; where customers and engineers define requirements.
• Development (Design, Implementation): Where the software is designed and programmed; producing the software.
• Validation: Evaluates the software to confirm it meets the customer's requirements.
• Evolution: Updates the software to meet changing demands.

Key Challenges Facing Software Engineering

• Coping with Increasing Diversity (heterogeneity) of software and hardware platforms.
• Demands for Reduced Delivery Times (delivery).
• Developing Trustworthy Software (trust).

Software Costs

• Roughly 60% development cost; 40% testing cost. Evolution often exceeds development in custom software
• Costs vary depending on the system being developed and its requirements (performance, reliability).
• Distribution of costs depends on the development model.
• Software engineering emphasizes cost-effectiveness.

Best Software Engineering Techniques and Methods

• No single method/technique is necessarily better than another.
• The most important factor is the type of application.

Different Types of Application

• 1. Stand-alone Applications: Operate independently on a local computer (e.g., office apps, photo editing).
• 2. Embedded Control Systems: Control and manage hardware devices (e.g., car anti-lock brakes, microwave oven).
• 3. Interactive Transaction-Based Applications: Enable real-time user interaction with a remote system (e.g., e-commerce, online banking).
• 4. Batch Processing Systems: Process data in large batches rather than real time (e.g., periodic billing, payroll).
• 5. Data Collection Systems: Gather data from multiple sources using sensors for further processing (e.g., agriculture, health monitoring)
• 6. Entertainment Systems: Primarily for personal use and entertainment.
• 7. Systems for Modeling and Simulation: Used to model physical processes.
• 8. Systems of Systems: Composed of multiple other software systems.

Software Engineering Fundamentals

• Fundamental principles apply to all types of software, regardless of development techniques.
• System development needs a managed, understood process (different for different types of software).
• Dependability and performance are important.
• Understanding and managing specifications and requirements are crucial.
• Reuse software where appropriate.

Software Engineering and the Web

• Web is a platform for applications; organizations are moving to web-based systems.
• Web services enable access to application functionality over the web.
• Cloud computing provides computer services; users pay for usage, not outright purchase.

Software Engineering Ethics

• Professional and ethical responsibilities extend beyond technical skills.
• Engineers must be honest and ethical to be respected professionals.
• Key Ethical Concerns: Confidentiality, Competence(avoid misrepresenting skills; honesty is paramount), Intellectual Property Rights (respecting and protecting rights and IP), and Computer Misuse.

Ethical Dilemmas

• Situations arise when stakeholders have differing views and objectives. Issues include disagreements with management policies; development of unethical products; developing military weapons.

Case Studies

• Examples of software systems: personal insulin pump, mental health management system, wilderness weather station.