Please enable JavaScript.
Coggle requires JavaScript to display documents.
Chapter 1 : Introduction to System Analysis and Design - Coggle Diagram
Chapter 1 : Introduction to System Analysis and Design
1.1 Information System
1) Information - Data that has been changed into a useful form of output 2) Information System - An information system combines information technology, people, and data to support business requirements
Information System Components
Hardware
A computer and peripheral equipment: Input, Output and storage devices; hardware also include data communication equipment
Software
Software refers to the program that control hardware and produce the desired or result
System Software - manages the hardware components which can include a single workstation or a global network with many thousand of client. Exp: Operating system, security software, device drivers
Application Software - consists of program that support day to day bussiness functions and provide users with the infformation they require. Exp : enterprise applications, include order proccessing systems, payroll systems, and company communication networks.
Data
Data is a raw material that an information system transforms into useful information
Processes
Processes describe the tasks and bussiness functions that users, managers, and IT staff members perform to achieve specific results
People
People who have an interest in an information system are called stakeholders
Type of Information System
Enterprise Computing System
Information system that support company-wide operations and data management requirements
Transaction Processing System
process data generated by day to day bussiness operations. Example of TP systems include customer order processing, accounts receivable, and warranty claim processing
Bussiness Support System
Analyze transactional data, generate information needed to manage and control bussiness processes, and provide information that lead to better decision-making
Knowledge Management System
Knowledge management system simulate human reasoning by combining a knowledge base and interference rules that determine how the knowledge is applied
User Productivity System
Companies provide employees at all levels with technology that improves productivity
Information System Integration
Most large companies require systems that combine transaction processing, business support, knowledge management, and user productivity features
System Development Method
Structured analysis
which is a traditional method that still is widely used
Object oriented (O-O) analysis
which is a more recent approach that many analysts prefer
Agile Method
also called adaptive method which include the latest trends in software development
System Development Life Cyle
Planning - Identify the nature and scope of the business opportunity or problem. System request-begins the process & describes problems or desired changes. The deliverable for planning is Preliminary investigation Report
Analyze - Purpose to build a logical model of the new system. Perform fact- finding using techniques such as interviews, surveys, document review, observation, and sampling The deliverable for the system analysis phase is the system requirements document
Design - purpose to create a physical model that will satisfy all documented requirements for the system. Design the user interface and identify necessary outputs, inputs, and processes. The deliverable for this phase is the system design specification
Development - the work divided in modules / units and actual coding is started. The code is produced so it is the main focus for the developer.
Testing - After the code is developed it tested against the requirement to make sure that the product is actually solving the need addressed and gathered during the requirement phase.
Implementation - The objective of the systems implementation phase to deliver a completely functioning and documented information system. Final preparations include converting data to new system's files, training users and performing the actual transition to the new system.
Maintenance- New system support operations. Maintenance changes correct errors or meet requirement. Enhancements increase system capability. Deliverables - Operational information system
What is SDLC
SDLC is a process followed for a software project, within a software organization. It consists of a detailed plan describing how to develop, maintain, replace and alter or enhance specific software
Types of Life Cycle Models
Waterfall Model
A linear- sequential life cycle model. Each phase must be completed before next phase can begin and there no overlapping in the phases. All these phases are cascaded to each other in which progress is seen as flowing steadily downwards( like a waterfall) through the phase.
Spiral Model
combines the idea of iterative development with the systematic, controlled aspect of the waterfall model
is a combination of iterative development model with high emphasis on risk analysis. It allows incremental releases of the product, or incremental refinement through each iteration around the spiral
Iterative and Incremental Development
In incremental model the whole requirement is divided into various builds. During each iteration, the development module goes through the requirements, design, implementation and testing phases. Each subsequent release of the module adds function to the previous release. The process continues till the complete system is ready as per the requirement.
Agile Model
combination of iterative and incremental process models with focus on process adaptability and customer satisfaction by rapid delivery of working software product. Break the product to small incremental builds. These builds are provide in iteration.
Prototyping Model
The software prototyping refers to building software application prototypes which display the functionality of the product under development but may not actually hold the exact logic of the original software.
Rapid Application Development
is a team-based technique that speeds up information systems development and produces a functioning information system. Companies uses RAD to reduces cost and development time, and increase the probability of success
Joint Application Development
is a user requirement elicitation process that involves the owner system and end users in the design and development of an application through a succession of collaborative workshops. The JAD approach leads to shorter development lifecycle and greater client satisfaction because it draw users and information systems analysts together to jointly design systems in facilitated group sessions