Introduction to Software Engineering

• Professional Software Development
  • What is meant by software engineering.
• Software engineering ethics
  • A brief introduction to ethical issues that affect Software Engineering.
• Case Studies
  • An introduction to three examples that are used in later chapters of the book

Software Engineering

Software engineering is an engineering discipline concerned with all aspects of the software production cycle, from the early stages of specification to maintaining the system after it is actually being used.

Engineering discipline – Using appropriate theroies and methods to solve the problems at hand, keeping in mind constraints that can be organizational, financial, or something else.

All aspects of software production – The technical parts are a minor detail in this class. Project management, the development of tools, methods to support software production are all important for Software Engineering.

Importance of Software Engineering

• Lots of people rely on technology, especially software, nowadays. It is important therefore to create reliable and trustworthy systems economically and quickly.
• In the long run, it is very worth investing in to using software engineering methods. If you were to treat it as a personal project, costs will usually follow on being able to change the software. Being able to maintain the software after it has gone in to use is critical.

Software Process Activities

• Software Specification
  • Customers and engineers define what software is needed to be produced and its respective constraints.
• Software development
  • This is where the software is desgined and programmed.
• Software validation
  • Making sure the software is actually what the customer wanted
• Software evolution
  • Modifying the software to adapt to changing customer and market needs.

General Issues that affect Software

• Heterogeneity
  • More and more systems are required to operate on distributed systems, across networks. This includes different types of computer and mobile devices.
• Business and social change
  • Business and societies change, and the software needs to reflect the changes. To be able to change the existing software and rapidly develop new software is not a trivial task.
• Security and trust
  • We need to be able to trust the software

Application Types

• Stand-alone applications
  • Application systems that usually run as standalone executables. They include all the necessary functionality and do not need to be connected to a network.
• Interactive transaction-based applications
  • These applications execute on a remote computer and are accessed by users from their own PCs or terminals. They include web apps such as e-commerce applications.
• Embedded control systems
  • There are ALOT of embedded systems, which are software control systems that control and manage hardware devices.
• Batch processing systems
  • Business systems that are designed to process large amounts of data, and create corresponding outputs.
• Entertainment systems
  • Systems primarily for personal use, like games
• Systems for modeling and simulation
  • Systems developed by scientists and engineers to model physical processes or situations which can include many, separate, interacting objects
• Data collection systems
  • Systems that collect data from their environment using sensors, and then send that data to other systems for processing
• Systems of systems
  • Systems that are composed of a number of other software systems

Software Engineering Diversity

• There are a great amount of types of software systems. Thus, there are no universal set of software techniques that is applicable to all of them.
• The software engineering methods and tools used depend on the type of application, the requirements of the customer, and the background of the development team.

Software Engineering Fundamentals

There are fundamental principles that apply to all types of software systems, regardless of the development techniques used.

• Systems should be developed using a managed understood development process.
• Dependability and performance are important for any system
• Understanding and managing the software specification and requirements are important
• When appropriate, reuse software that has already been developed instead of writing new software

Software Engineering Ethics

• Being honest and ethically responsible is necessary as a software engineer
• Following principles that are morally right is important

Issues of Professional Responsibility

• Confidentiality
  • Respecting the confidentiality of employers/clients is understood to be necessary.
• Competence
  • Engineers shouldn’t do work they know is out of reach of their competence.
• IP (Intellectual Property) rights
  • Engineers should be aware of laws governing the use of IP and ensure the IP of employers/clients is protected
• Computer misuse
  • Engineers should not use their technical skills to misuse other computers.