Requirements Engineering: Processes, Types, and Validation in Software Development

What is requirements engineering?

The process of establishing the services that a customer requires from a system and the constraints under which it operates and is developed.

What are system requirements?

Descriptions of the system services and constraints generated during the requirements engineering process.

What is a requirement?

A statement that may range from a high-level abstract service or system constraint to a detailed mathematical functional specification.

What are user requirements?

Statements in natural language plus diagrams of the services the system provides and its operational constraints, written for customers.

Who are system stakeholders?

Any person or organization affected by the system, including end users, system managers, system owners, and external stakeholders.

What is the role of a medical ethics manager in the Mentcare system?

To ensure that the system meets current ethical guidelines for patient care.

What do agile methods argue regarding detailed system requirements?

They argue that producing detailed system requirements is a waste of time as requirements change quickly.

What are functional requirements?

Requirements that describe functionality or system services, detailing what the system should do.

What are non-functional requirements?

Constraints on the services or functions offered by the system, often applying to the entire system rather than individual features.

What is an example of a functional requirement for the Mentcare system?

A user shall be able to search the appointments lists for all clinics.

What is requirements imprecision?

Problems that arise when functional requirements are not precisely stated, leading to different interpretations.

What does it mean for requirements to be complete?

They should include descriptions of all facilities required.

What does it mean for requirements to be consistent?

There should be no conflicts or contradictions in the descriptions of the system facilities.

Why might non-functional requirements be more critical than functional requirements?

If non-functional requirements are not met, the system may be rendered useless.

How can non-functional requirements affect system architecture?

They may require organizing the system to minimize communications between components to meet performance requirements.

What is the dual function of requirements?

They may serve as the basis for a bid for a contract and as the basis for the contract itself.

What is meant by requirements elicitation?

The process of gathering the requirements from stakeholders.

What is requirements validation?

The process of ensuring that the requirements accurately reflect the needs of the stakeholders.

What is requirements change?

The process of managing changes to the requirements throughout the development lifecycle.

What is the significance of the term 'search' in functional requirements?

It can be interpreted differently by users and developers, leading to ambiguity.

What are the two types of requirements discussed in requirements engineering?

Functional requirements and non-functional requirements.

What is the importance of stakeholder identification in requirements engineering?

To ensure that all parties affected by the system have their needs considered.

What is the purpose of a requirements document?

To define the needs of the client and guide the development process.

What is a structured document in the context of system requirements?

A document that details the system's functions, services, and operational constraints.

What is the role of IT staff in the Mentcare system?

To be responsible for installing and maintaining the system.

What is the impact of ambiguous requirements?

They may lead to misinterpretation and incorrect implementation by developers.

What is the purpose of organizing a system to minimize communications between components?

To ensure that performance requirements are met.

What can a single non-functional requirement generate?

A number of related functional requirements that define necessary system services.

What are product requirements?

Requirements specifying that the delivered product must behave in a particular way, such as execution speed and reliability.

What are organizational requirements?

Requirements that arise from organizational policies and procedures, like process standards and implementation requirements.

What are external requirements?

Requirements that arise from external factors, such as interoperability and legislative requirements.

What is an example of a product requirement in the Mentcare system?

The system shall be available to all clinics during normal working hours with a downtime not exceeding five seconds in one day.

What is a verifiable non-functional requirement?

A statement that can be objectively tested using measurable criteria.

What is a goal in the context of requirements engineering?

A general intention of the user, such as ease of use.

What is a usability requirement for the Mentcare system?

The system should be easy to use by medical staff and organized to minimize user errors.

What are the metrics for specifying non-functional requirements related to speed?

Processed transactions per second, user/event response time, and screen refresh time.

What are the stages of requirements elicitation?

Requirements discovery, classification and organization, prioritization and negotiation, and specification.

What is the main challenge in requirements elicitation?

Stakeholders often do not know what they really want or express requirements in their own terms.

What is the process of requirements discovery?

Gathering information about required and existing systems and distilling user and system requirements.

What types of interviews are used in requirements elicitation?

Closed interviews based on predetermined questions and open interviews exploring various issues.

What is effective interviewing in requirements engineering?

Being open-minded, avoiding preconceived ideas, and prompting discussions with stakeholders.

What is the role of stakeholders in requirements elicitation?

They provide insights about the application domain, services needed, and operational constraints.

What is a common problem with stakeholder interviews?

Application specialists may use language that is difficult for requirements engineers to understand.

What is the importance of requirements prioritization?

To resolve conflicts between different stakeholder requirements and ensure critical needs are addressed.

What does the term 'requirements specification' refer to?

The documentation of requirements that will be input into the next round of the development process.

What is the significance of the iterative nature of requirements engineering?

It allows for continuous refinement and adjustment of requirements based on stakeholder feedback.

What is the impact of changing business environments on requirements?

Requirements may change during the analysis process as new stakeholders emerge and conditions evolve.

What is meant by 'requirements classification and organization'?

Grouping related requirements and organizing them into coherent clusters for better management.

What is the goal of requirements validation?

To ensure that the requirements accurately reflect the needs and constraints of stakeholders.

What is the relationship between goals and verifiable non-functional requirements?

Goals convey user intentions, while verifiable requirements provide measurable criteria for those goals.

What challenges arise from conflicting requirements among stakeholders?

Different stakeholders may have varying priorities and needs, complicating the requirements process.

What is the role of technical staff in requirements elicitation?

They work with customers to understand the application domain and necessary system services.

What is the significance of user training in usability requirements?

Medical staff should be able to use all system functions after a specified amount of training.

Why are interviews not effective for understanding domain requirements?

Requirements engineers often cannot understand specific domain terminology, and some domain knowledge is too familiar for people to articulate.

What is ethnography in the context of requirements engineering?

Ethnography involves a social scientist observing and analyzing how people actually work without requiring them to articulate their processes.

What are the benefits of ethnographic studies?

They reveal that work is usually richer and more complex than simple system models suggest.

What type of requirements does ethnography derive?

Requirements derived from actual work practices and cooperation among individuals.

What is focused ethnography?

A method that combines ethnography with prototyping, developed from studying air traffic control processes.

What is the limitation of ethnography?

It is effective for understanding existing processes but cannot identify new features for a system.

What are scenarios and user stories?

They are real-life examples describing how a system can be used for a particular task.

What should scenarios include?

A description of the starting situation, normal flow of events, potential issues, concurrent activities, and the final state.

What is the initial assumption for uploading photos to KidsTakePics?

A user has one or more digital photographs saved on a device and has logged into KidsTakePics.

What happens during the normal upload process?

The user selects photos, chooses a project name, and can input keywords before the system sends a notification to the moderator.

What can go wrong during the photo upload process?

Issues include no moderator being assigned, duplicate photo names, or other activities by the moderator.

What is requirements specification?

The process of documenting user and system requirements in a requirements document.

What must user requirements be like?

They must be understandable by end-users and customers without a technical background.

How are system requirements different from user requirements?

System requirements are more detailed and may include technical information.

What is the importance of complete requirements?

Complete requirements are crucial as they may form part of a contract for system development.

What is natural language notation in requirements specification?

Requirements are written using numbered sentences in natural language, each expressing one requirement.

What is structured natural language?

Requirements written in natural language on a standard form or template, providing specific information about each requirement.

What are design description languages?

Languages that specify requirements by defining an operational model of the system, though they are rarely used today.

What are graphical notations in requirements specification?

Graphical models with text annotations used to define functional requirements, commonly using UML diagrams.

What are mathematical specifications?

Notations based on mathematical concepts that provide unambiguous specifications, though they may be difficult for customers to understand.

What is the role of a project moderator in photo sharing?

The moderator approves photos as they are uploaded and ensures content moderation.

What happens if a user tries to upload a photo with a duplicate name?

The user is prompted to re-upload, rename, or cancel the upload, with options to overwrite or automatically rename the photo.

What is the significance of user stories in requirements engineering?

User stories help stakeholders relate to practical situations and provide feedback based on their experiences.

How does awareness of others' activities influence work processes?

Awareness leads to changes in how individuals perform their tasks, impacting overall workflow.

What is the main focus of ethnographic studies?

To understand existing work practices and the social and organizational factors that influence them.

What is the outcome of the upload process in KidsTakePics?

Photos are uploaded and assigned a status of 'awaiting moderation', visible to both the user and the moderator.

What is the challenge of using ethnography for requirements analysis?

Ethnography may study outdated practices that no longer reflect current needs or relevance.

What does the term 'scenarios' refer to in requirements engineering?

Structured descriptions of how a system may be used, including various outcomes and activities.

What is the primary distinction between requirements and design?

Requirements state what the system should do, while design describes how it does this.

Why are requirements and design considered inseparable in practice?

A system architecture may structure the requirements, and the system may inter-operate with others that generate design requirements.

What is the benefit of using natural language for writing requirements?

Natural language is expressive, intuitive, and universal, making it understandable by users and customers.

What should be included in the rationale of a requirement?

An explanation of why the requirement is necessary.

What is a common problem with natural language specifications?

Lack of clarity, confusion between functional and non-functional requirements, and amalgamation of several requirements together.

What is a structured specification?

An approach to writing requirements in a standard way that limits the freedom of the requirements writer.

What are form-based specifications?

Specifications that define the function or entity, inputs, outputs, actions, and conditions related to a requirement.

How does a tabular specification supplement natural language?

It is particularly useful for defining several possible alternative courses of action.

What do use cases identify in a system?

Use cases identify the actors in an interaction and describe the interaction itself.

What is the purpose of the software requirements document?

It is the official statement of what is required of the system developers, defining user and system requirements.

What is the significance of requirements document variability?

The information in a requirements document depends on the type of system and the development approach used.

What should the preface of a requirements document include?

It should define the expected readership and describe the version history, including changes made.

What should the introduction of a requirements document describe?

The need for the system, its functions, and how it fits into the organization's strategic objectives.

What is included in the user requirements definition section?

Services provided for the user and non-functional system requirements, using understandable language and diagrams.

What does the system architecture chapter present?

A high-level overview of the anticipated system architecture and the distribution of functions across modules.

What details are covered in the system requirements specification?

Functional and non-functional requirements in detail, including interfaces to other systems.

What might system models include in a requirements document?

Graphical models showing relationships between system components and the system's environment.

What is the role of diagrams and tables in requirements specifications?

They supplement natural language to clarify and organize requirements.

What is the recommended language for mandatory requirements?

The word 'shall' should be used for mandatory requirements.