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System Analysis and Design Study Notes

• This document is a guide and question bank for preparing for a system analysis and design exam.
• It covers the fundamental topics and concepts needed to understand the principles and practices of system analysis and design.
• Studying this material will provide valuable knowledge about methods for analyzing and designing systems.
• The document was downloaded from studocu.com.
• The file is from the University of South Africa and the author is not mentioned.

Information System

• An information system is a set of computer components used to collect, process, store, and provide information for business tasks.
• Computer applications are software programs executed on a computing device to perform specific functions.
• Systems analysis aims to understand system needs and requirements to document these specifications. It's essential because a software architect needs to understand and capture the vision of project sponsors before coding.
• Systems analysts describe system requirements in detail, specifying functionality, reliability, performance, and security.

Activities of Systems Analysis

• Systems analysts gather detailed information through interviews and observations of end users and current systems.
• They research planning documents, policies, and similar systems to understand existing needs.
• They define requirements, identifying functional needs and non-functional aspects (performance, reliability, and security) for the new system.
• Analysts prioritize requirements, considering the importance and necessity of each element, avoiding scope creep.
• User validation of interfaces is crucial for efficient systems.
• Prototypes are helpful for understanding system capabilities.
• Prototypes developed early can be expanded into functional system parts later.

Projects

• Projects are planned undertakings with a clear start and end for creating a new system.
• Project management frames guidance for large-scale projects.

Core Software Processes

• Six core processes are crucial for software system development, though there are many variations depending on the project needs.
• These processes include identifying problems, defining system requirements, planning, building, testing, and deployment.

Agile Development

• Agile development prioritizes responding to changes rather than strict adherence to a plan, allowing for flexibility and responsiveness to new issues.

System Vision Document (SVD)

• An SVD outlines the system's benefits and capabilities, along with cost estimations, benefiting company planning and future system development.

System vs Subsystem

• A subsystem is a component of an overall system or a group of related functions within a system.

Work Breakdown Structure

• A work breakdown structure (WBS) is a detailed list of tasks required for a project. It organizes tasks in a manageable format for planning and execution.

Use Cases

• A use case represents a single business event and the system's response to it.
• Use case diagrams visually depict use cases and the actors associated with them.
• Use cases are identified through user goal and event decomposition techniques.

Class Diagrams

• Class diagrams illustrate which entities have been determined as object classes, their attributes, and relationships.
• They visually represent the data structures needed in a system.

Activity Diagrams

• Activity diagrams are flowcharts that visually represent the steps involved in a process, use cases, or tasks within a system.

System Testing

• System testing follows steps such as setting up test data, conducting testing, identifying errors, and rectifying errors.

User Acceptance Testing (UAT)

• UAT verifies that systems fulfil user requirements.

Iterative Development

• Iterative development involves repeating a series of steps in a cyclic manner, allowing for changes as needed. This is valuable for understanding new requirements or issues.

Functional and Non-Functional Requirements

• Functional requirements define the functions a system must perform.
• Non-functional requirements describe characteristics like performance, reliability, and security.

Information Gathering Techniques

• Techniques like interviews, questionnaires, observation of existing systems, and review of documents help analysts collect information from and about stakeholders.

CRUD Technique

• CRUD (Create, Read, Update, Delete) techniques can help cross-check requirements. It ensures that every data consideration (CRUD operation) in the system is accounted for in the use cases.

UML (Unified Modeling Language)

• UML is a standardised approach for object-oriented system modelling, including its diagrams and classes.
• UML has a standardised design language to model systems.

Use Case Realization

• Use case realization focuses on identifying important classes and their interactions for a specific use case.

Architectural Design

• Architectural design focuses on the big picture of a system's overall structure.
• An important UML diagram for architectural design is the component diagram.

Security Issues

• Security and data encryption must be considered in system design, particularly when dealing with online or externally accessed systems.

Server Architectures

• Three-tier architectures separate user interface from business logic and database access, improving flexibility and maintainability; this is a robust method for complex business situations.

Cloud Computing vs Virtual Servers

• Cloud computing provides greater scalability compared to traditional dedicated servers, but server configurations and access remain important distinctions.