Engenharia de Software - Aula 01 - Modelos de processo de software e atividades de software

Summary

Professor Marcelo Fantinato introduces software engineering, focusing on different software process models like the waterfall, incremental development, and software reuse. He explains the importance of software quality attributes such as functionality, performance, and reliability. The lecture covers the distinction between software engineering and computer science, emphasizing the practical aspects of software creation. It also addresses the evolution of software processes and challenges like balancing speed and reliability. The professor highlights that various organizations may choose different models based on their needs and size, setting the stage for deeper exploration in future classes.

Takeaways

• 😀 The course is focused on software engineering, specifically models and activities related to software processes.
• 😀 Software development can follow different process models depending on the organization, team size, and the complexity of the project.
• 😀 There is a historical evolution in the way software development models have been approached, from early methods to modern agile methods.
• 😀 A basic definition of software includes not only the program itself but also the documentation, such as user manuals and project specifications.
• 😀 Key attributes of good software include functionality, performance, reliability, maintainability, and usability.
• 😀 Software engineering differs from computer science in that it focuses on the practical aspects of developing software, while computer science is more theory-based.
• 😀 The major activities in software engineering are specification, development, validation, and evolution of the software.
• 😀 Software development models can be broadly categorized into traditional models like the waterfall model, incremental development, and reuse-based models.
• 😀 The waterfall model initially appeared as a linear process, but later iterations acknowledged the need for feedback loops, creating a more flexible approach.
• 😀 Incremental development involves creating an initial version of the software, then refining it through several iterations until the final product is reached.
• 😀 Reuse models leverage pre-existing software components to accelerate development, similar to building a house using pre-assembled parts.
• 😀 The engineering of software involves various sub-processes such as requirements gathering, system design, coding, testing, and maintenance.

Q & A

What is the main topic of this video lecture?

The main topic of the video lecture is 'Software Process Models and Software Activities.' The lecture focuses on the systematic approach to software development and the various models used in the engineering of software.

What does 'Software Process Models' mean in the context of the lecture?

'Software Process Models' refers to different approaches or frameworks that guide how software development processes are organized and executed. These models allow organizations to structure their development processes based on their size, needs, and goals.

How do different organizations influence the choice of software process model?

Different organizations choose software process models based on their size, complexity, and type of software they are developing. Larger companies may prefer more structured, systematic models, while smaller companies might opt for simpler approaches. The choice also depends on the organization’s resources and the geographical distribution of its teams.

What historical context is provided regarding the evolution of software development models?

The lecture mentions that software process models evolved over time, starting from the 1970s. Initially, companies followed simple approaches, but as software development became more complex, models like agile development emerged, addressing the need for more flexible and iterative development methods.

What is the definition of 'software' according to the lecture?

Software is not only the computer program that runs on a system but also includes all associated documentation. This encompasses user manuals, help documentation, and the documentation created during the software development process, such as requirement specifications.

What are some key attributes of 'good' software?

Good software should meet several attributes: functionality (meeting user expectations), performance, reliability, maintainability, and usability. These attributes ensure the software serves its intended purpose effectively and can be easily updated and maintained.

How does software engineering differ from computer science?

Software engineering focuses on the practical aspects of software development, dealing with the creation and maintenance of software systems. In contrast, computer science is more concerned with the theoretical foundations and the study of algorithms, computations, and data structures.

What are the fundamental activities involved in software engineering?

The fundamental activities in software engineering are specification, development, validation, and evolution of software. These stages encompass defining what the software should do, designing how it will work, building it, testing it, and maintaining it over time.

What are the three traditional software process models introduced in the lecture?

The three traditional software process models discussed are the Waterfall model, the Incremental model, and the Reuse-based model. The Waterfall model follows a linear, sequential process, the Incremental model develops software in iterative, smaller pieces, and the Reuse-based model focuses on using pre-existing software components to build new systems.

What is the 'Waterfall model,' and how does it work?

The Waterfall model is a traditional, linear software development process that proceeds through distinct stages, including requirements definition, design, implementation, testing, and maintenance. The model is called 'Waterfall' because the process is viewed as cascading down through these stages. However, in practice, iteration and feedback often occur between the stages.

How does the 'Incremental model' differ from the 'Waterfall model'?

The Incremental model differs from the Waterfall model by allowing for the development of software in smaller, iterative versions. Each increment is a functional version of the software that builds on the previous one. This approach allows for more flexibility and ongoing validation with the client, unlike the Waterfall model, which assumes a rigid, one-directional flow.

What role does software reuse play in the 'Reuse-based model'?

In the Reuse-based model, the focus is on reusing existing software components to create new systems. By utilizing pre-existing, tested components, development time can be reduced, and cost efficiency can be improved. The approach is similar to building a structure using prefabricated parts, where the initial design may be adapted to integrate these components effectively.

How are software testing and validation approached in the lecture?

Software testing is approached in several stages, including unit testing of individual components, integration testing of combined components, and acceptance testing with the client to ensure the software meets the specified requirements. The importance of validation throughout the process is emphasized to ensure the software is reliable and meets user needs.

What is meant by the 'evolution' of software in the context of the software development process?

Evolution in software refers to the continuous improvement and adaptation of the software after it is released. This includes maintaining the software, correcting errors, and updating it to meet new requirements or improve functionality. Software evolution ensures that the system remains useful and efficient over time.