Software Quality Engineering Lecture 1

Software Quality Engineering - Lecture 1 Notes

• Software Quality Engineering (SQE): The process of implementing quality checks throughout the entire development cycle to ensure high-quality software

• Goal of SQE: To ensure product quality from the beginning, minimizing defects and improving the process

• Definition of Quality: IEEE defines quality as the degree to which a system, component, or process meets:

  • Specified requirements
  • Customer or user needs and expectations

• How Quality is Perceived (David Garvin):

  • Transcendental: Quality can be recognized but not defined
  • User: Quality is fitness for purpose or customer satisfaction
  • Manufacturing: Quality is conformance to specifications
  • Product: Quality is tied to inherent product characteristics
  • Value-Based: Quality depends on the amount a customer is willing to pay

• Arriving at Definition of Quality:

  • User View: Quality is fulfillment of customer needs and achieving customer satisfaction (held by Juran). A deficiency of this view is that customer responsibility for details of specifications is unclear. Customer needs may change during development.
  • Manufacturing View: Quality is conformance to specifications (held by Crosby and Standards Organizations). A deficiency is specifications may not consider customer needs. Quality products might not address customer problems

• Definition of Software Quality:

  • Software quality is the fitness for use of the software product. (Summary of opinions of Humphrey, Denning and Dromey)

• What Quality is Composed of:

  • Quality Attribute: The basic building block on which fitness for use is based. Features (property, attribute) of the product, materials, and process needed for fitness of use

• Software Quality Assurance (SQA):

  • A planned, systematic pattern of actions to achieve confidence in product conformance to technical requirements (IEEE)
  • Unlike hardware, software quality stays constant. Software quality assurance is a systematic process to improve product quality.
  • SQA involves both process and product assurance to assure that software projects fulfill their quality goals.

• SQA Activities

  • Quality Control (Downstream): Post-implementation testing to ensure the product matches specifications
  • Quality Control (Upstream): Occasional/systematic checks during development to determine conformance to standards. This includes reviews and inspections

• Process Quality:

  • Quality of a product is determined by quality of the process used for development and maintenance

• Software Quality Engineering (SQE) Activity (The Envelope Activity):

  • Ensures proper procedures are applied throughout, continuously checking product quality and evaluating quality at the end of development, evaluating process quality

• Primary goals of software quality engineering:

  • Process control and oversight.
  • Implementing standards and metrics
  • Data collection and analysis
  • Test development
  • Identification of issues and solutions
  • Follow-up actions

• Software Practices for Quality Engineering:

  • Functional Testing: Evaluating user interfaces (UI) and APIs to ensure specifications are met
  • Peer Review: Assessing source code for efficiency and logic, promoting collaboration, and addressing clear communication of programming ideas
  • Static Code Analysis: Using automated tools to perform analysis of code based on predefined standards to identify quality issues
  • Unit Testing: Checking code units (components, methods, classes) against inputs to ensure validity
  • User Performance Testing: Evaluating the speed of a product in different environments to ensure user experience meets quality standards.

Explore the fundamentals of Software Quality Engineering in this first lecture. Learn about the processes for implementing quality checks throughout the software development cycle and the various definitions and perceptions of quality. This quiz will help reinforce key concepts and their implications for software development.