Introduction to Software Engineering

• Software engineering is crucial for government, society, businesses, and institutions because the modern world relies on software to function.
• Software is used to control national infrastructures, utilities, electrical products, industrial manufacturing, financial systems, and entertainment.
• Over 75% of the world's population uses software-controlled mobile phones and nearly all will be Internet-enabled soon.
• Software systems are abstract and intangible, lacking physical constraints which both simplifies engineering and allows complexity.
• Software systems can rapidly become very complex, hard to understand and expensive to change.
• There is a wide range of software systems, from simple embedded systems to complex worldwide information systems, needing different approaches for engineering.
• Software failures are criticized as inadequate but are often due to system complexity, and failure to use correct software engineering techniques.
• New techniques help build larger, complex systems but demands change, requiring faster delivery and new capabilities; new techniques are developed to meet these challenges.
• Companies, drifting into software development without using software engineering methods, make software more expensive and less reliable.
• Better software engineering education and training is needed to combat that.
• Software engineers have made space exploration, the Internet, and telecommunications possible, and made travel safer.
• Key challenges in the 21st century include climate change and declining natural resources.

Professional Software Development

• Software development is a professional activity where software is made for business purposes like information systems and computer-aided design systems.
• Professional software is for use by others and made by teams and is maintained over time.
• Software engineering supports professional development with techniques such as program specification, design, and evolution.
• Professional software isn't just programs, it includes documentation, libraries, websites, and configuration data.
• A professional system may include several programs and configuration files, system documentation, user guides, and product information websites.
• Amateur differs from professional, in that no one else will use it

Software Defined

• Software is computer programs and their associated documentation, developed for specific clients or general market use.
• Good software is functional, has good performance, is maintainable, dependable, and usable.
• Software engineering is an engineering discipline that handles all parts of software production from start to finish of it's useful life.
• Fundamental activities include software specification, development, validation, and evolution.
• Computer science is about the theory, while software engineering focuses on the practical part of creating and delivering useful software.
• System engineering includes all computer aspects including software engineering, hardware, and process engineering.
• Key challenges are diversity, reduced timelines, and trustworthy software.
• Development costs account for 60% while testing is at 40% of software costs; for custom software, evolution costs are often higher than development.
• Projects should be managed and developed with relevant techniques based on system type.
• Games use prototypes, safety-critical systems need complete specification.
• The Internet has led to distributed systems, service-based systems, and the app industry, changing software's financial side.

Software Engineering

• It is a discipline that handles all aspects of software production, from the system specification to after maintaining it.
• Engineers apply theories, methods, and tools selectively, always seeking solutions, while working in financial constraints.
• It also manages projects and develops tools, methods, and theories for support.
• Engineering delivers results of required quality within time and budget, making compromises.
• Software engineers must adopt a systematic and organized approach to produce high-quality software.
• Choosing the right method is imperative, a creative approach may work for some software.
• Flexible software processes suit interactive web-based systems and mobile apps, which blend software with graphical design skills.
• Software engineering is useful because society relies on advanced systems, and it's cheaper to use engineering rather than just write the code.
• Failure to use engineering leads to higher costs and long term maintainance.
• Software process is a set of activities leading to product production.
• These fundamental activities include: software specification, software development, software validation, and software evolution.
• System types require different development processes as real-time and e-commerce systems have different specificiation processes
• Software engineering relates to both computer science and systems engineering.
• Computer science focuses on theory, while software focuses on practical problems of actual production.
• System engineering relates to development and evolution where software is a major role, including hardware, policy, process, and deployment.
• There are no universal methods, but there are four related issues that affect many types of software: heterogeneity, business and social change, security and trust, and scale.
• Systems must operate as distributed systems across networks and devices, including older legacy systems.
• Develop techniques for flexible and dependable software.
• Businesses must rapidly change existing software and develop new.
• Traditional techniques are time-consuming and often take longer than planned.
• Software must be trustworthy, especially for remote systems, with maintained information security.
• Software scales across embedded systems in wearables to Internet-scale systems.
• New tools and techniques are needed.

Software Engineering Diversity

• Software engineering uses a systematic approach to produce software considering cost, schedule, and dependability.
• Specific methods and tools depend on the organization, software type, and people involved.
• Diverse tools have developed, while the SEMAT initiative suggests a fundamental meta-process for different processes.
• Application determines importance of software engineering methods.

Types Of Application

• Stand-alone applications have all functionality and may not connect to a network, such as office apps and CAD software.
• Interactive transaction-based apps run on a remote computer and are accessed by users to buy goods and access business systems with large updated data stores.
• Embedded control systems control hardware with many examples including cell phones, car antilock brakes, and microwave cooking processes.
• Batch processing systems process data in large batches like billing and salary payment systems.
• Entertainment systems are for users for personal use, mainly console games, that prioritize quality user interaction.
• Systems for modeling and simulation model physical processes developed by scientists and engineers.
• Data collection and analysis systems use sensors that send data for processing, often in hostile environments using cloud-based systems.
• Systems of systems, common in enterprises, consist of several software systems, incorporating generic and specially written software.
• Each system type requires special engineering as control systems in cars need verification.
• Interactive web-based systems rely on iterative development, reusable components.
• Specification is important for systems of systems development, there are crucial fundamentals.

Software Engineering Fundamentals

• All systems must be developed using a managed and understood process with defined planning.
• Dependability and operation are important for all systems to operate as expected and securely.
• It is important to understand software specification and requirements management and know/manage customer expectations for delivery on time and budget.
• Effective use of existing resources with reuse of existing software.
• Process, dependability, requirements, management, and reuse are key themes for professional software development.
• Fundamentals are independent with regards to the programming language used but specific programming techniques vary dramatically.

Internet Software Engineering

• The Internet has a huge effect on software systems.
• Initially, the web was a way for people to see information across the world but later had profound impacts with functionality to browsers that led to the development of new system products that delivered new services, and were often funded by advertisements that delivered services to the users
• The development of web browsers that could run small programs did local processing that led to web based business and organizational software.
• Instead of deploying the software into local computers, web based servers cheaper to change and upgrade, and reduced costs.
• Most have shifted in web based interaction.
• Now the standard approach is the delivery of web based systems like Google Apps Microsoft and Adobe creative suite on clouds.
• Users shared the system but didn't physically buy the software or pay for the service.
• The Internet changed the way business software is delivered with the development of communication across the world.
• Business applications evolved programming with extensive reuse of components and programs.

Software Engineering Changes

• Software reuse has become the dominant, assembling systems with existing software.
• Web-based systems are always developed and delivered incrementally.
• Software may be implemented using service-oriented engineering.
• Interface development involves support for the creation of rich interfaces with a web browser.
• Internet is applicable for all types of software and relevant to scale and complexity.

Software Engineering Ethics

• Software engineering abides by social and legal framework
• Software engineers have responsibilities beyond technical skills and must act ethically to maintain respect
• There are behaviors that are not required by law, but fall under the professional code: confidentiality, competence, and intellectual property rights.
• You should not use technical skills to abuse other personal computer misuse and abuses should be kept to a minimum.
• Professional societies set ethical standards with institutions that maintain a code of conduct and ethics.
• The ACM and the IEEE have created a general code.
• Ensure efforts are used for good software engineering and maintain commitment

Code Principles

• Engineers must commit themselves to making the analysis, specification, design, development, testing, and maintenance for beneficial software.
• Public: Act consistently in public interest.
• Client and employer: Act in the best interest with client.
• Product: Meet the highest professional standards.
• Judgement: Maintain integrity and independence.
• Management: Should promote ethical approaches.
• Profession: Should advance with high integrity.
• Colleagues: Should be fair and supportive.
• Self: Should be lifelong learning.
• Ethical dilemmas are often faced with different views and objectives which can lead to disagreement.
• One needs to respond adequately for their situation.
• A difficult situation for professional engineers is if their employers act unethically.
• There are no absolutes with safety; engineers must make the best choices.
• One must make up their own mind and be appropriate.
• Military/nuclear systems pose ethical issues, with different views on participating in defense systems.
• Communicate in advance and exert no pressure to take such projects.
• There are philosophical and concrete means to approach ethical concerns and discuss and find a solution for a group of individuals.

Case Studies

• One should illustrate software concepts, the practice differs based on system types.
• The system types include embedded systems, information systems, sensor-based data collections, and support environments.
• Embedded systems are where the software controls hardware, such as an insulin pump system.
• Information systems manage and provide access to information, like medical records.
• Data Collection systems collect/process data in real time or in hostile environments from sensors.
• Support environments are tools used to support an activity, like programming environment.

Intravenous Pump

• An intricate system simulating the functions of the pancreas in the human body.
• It collects data from an embedded sensor.
• It directly controls with an automated pump that delivers a dose of insulin to the patient.
• It allows for blood glucose to be balanced and regulated to provide a safe treatment from diabetes.
• Requires key things such as delivering the right amount and performing it reliably.
• It should be designed so it follows key factors.

Patient Information System for Mental Health Care (Mentcare)

• It is a system to support mental healthcare and maintains information about patients in hospital from their treatments.
• Clinics are not in hospitals and are available to provide care easier closer to patients.
• The system is intended for clinic which is also available on a laptop safely with secure access.
• Patients may miss appointments or forget instructions, clinics unexpectedly, may be a danger that requires to be sectioned.
• Users have access depending on the medical or non medical background.
• The system records data of patients such as treatments and condition.
• It generates interval alerts with medical authority through reports.
• Key features include individual care and the systems involved,
• This includes the patient monitoring with system alerts and the administrative reporting for management.
• The patients medical health and laws must be followed for the confidentiality
• Privacy is crucial especially on the safety critical systems since the patients causes damage or are suicidal.
• It must provide the most comprehensive designs possible with the data and safety requirements.

Wilderness Weather Station

• Helps measure the climate change and improve accuracy in forecast of storms through use of wilderness deployed weather stations in remote areas.
• It allows instruments to measure all basic atmospheric measures with instrument.
• It collects and makes it available for other systems to view the processing.
• This responsible collection is responsible with weather data and transfers some initial process to data.
• Each of weather stations connects via satellite and has maintenance to monitor all the health.
• Can also update to have a remotely controlled weather.
• Weather stations need to consider the weather parameters and the instrumentation.
• It also includes parameter readings with a software system.
• Gathers data points for each measure through observations.
• Bandwidth needs to be taken into account because the satellite aggregation of data.
• Each wearther station is battery powdered and must be self-contained.
• Every communication and through a satellite.
• Wind/Solar has to be taken because station has to be powered through extreme and sever weather.
• Software needs to be monitoring, power reporting, the the system.
• Generators also must be taken in potentially damaging environment conditions.
• Allow the reconfiguration of certain parts of software.

Digital Learning

• Interactive and to support education in students.
• There is no general strategy to support tools.
• They depend based on the age of the students.
• Design tools and framework to provide learners to use the system for example authentication.
• There is synchronous data to use the service.
• Tools in the environment are chosen by teachers to suit needs.
• In addition of Virtual Learning for management learning
• High architecture module
• Service oriented system for all applications to improve.
• Three types of services with utility, application, and configuration services.
• Utility services have been independent and designed specifically.
• The application services allow services and is external so access and data.
• The environment is defined between all users.
• It can accommodate all applications.
• Two levels of integrations being the integrated and independent.
• Integrated has direct access for certain programs and be authentication
• Other authentication may be called on by other resources.
• Independent services allow with the services that can share users.
• Independent services are used and the development time may allow to come integrate the service to support and have a service.