Systems Analysis and Design

horizontal system

A basic system, such as an inventory or payroll package that is commonly used by a variety of companies.

System Request

A formal request to the IT department that describes problems or desired changes in an information system or business process. It might propose enhancements for an existing system, the correction of problems, or the development of an entirely new system.

server farm

A large concentration of servers working together

Economic Feasibility

A process of identifying the financial benefits and costs associated with a development project.

mission-critical system

An information system that is vital to a company's operations.

Transaction Processing System (TPS)

Basic business system that serves the operational level and assists in making structured decisions

System Implementation phase

During this phase the new system is constructed, programs are written, tested, and documented, and the system is installed

System planning phase

During this phase the systems project gets started. The project proposal is evaluated to determine its feasibility. The project management plan is formulated, with the help of CASE tools where appropriate

Enterprise Applications

Include order processing systems, payroll systems, and company communications networks

project creep

Projects with very general scope definitions are at risk of expanding gradually, without specific authorization

Scalability

Refers to a system's ability to handle increased volume and transactions in the future

Business Case

Refers to the reasons, or justification, for a proposal.

systems requirements document

The end product of the SDLC systems analysis phase

System Development Life Cycle (SDLC)

The overall process for developing information systems from planning and analysis through implementation and maintenance

System Design Phase

The purpose of systems design is to create a blueprint for the new system that will satisfy all documented requirements, whether the system is being developed in-house or purchased as a package

System Analysis Phase

The purpose of this phase is to build a logical model of the new system

system requirement

a characteristic or feature that must be included in an information system to satisfy business requirements and be acceptable to users

data flow

a path for data to move from one part of the information system to another

Entity

a rectangle, which may be shaded to make it look three-dimensional

constratint

a requirement or condition that the system must satisfy or an outcome that the system must achieve

Systen

a set of related components that produces specific results

Business process

a specific set of transactions, events, and results that can be described and documented

Systems Analysis and Design

a step-by step process for developing high-quality information systems

Enterprise Resource Planning (ERP)

a suite of applications called modules, a database, and a set of inherent processes for consolidating business operations into a single, consistent, computing platform

system analyst

a valued member of the IT department team who helps plan, develop, and maintain information systems

Fishbone diagram

a visual aid that helps organize cause and effect relationships for "things gone wrong"

Physical Model

built that describes how the system will be constructed

Information System

combines technology, people, and data to provide support for business functions such as order processing, inventory control, human resources, accounting, and many more

Hardware

consists of everything in the physical layer of the information system.

Application Software

consists of programs that support day-to-day business functions and provide users with the information they need

Project scope

defining the specific boundaries, or extent, of the project

Processes

describe the tasks and business functions that users, managers, and IT staff members perform to achieve specific results.

vertical system

designed to meet the unique requirements of a specific business or industry, such as an online retailer, a medical practice, or an auto dealership

feasibility study

investigation that gauges the probability of success of a proposed project and provides a rough assessment of the project's feasibility

system software

manages the hardware components, which can include a single computer or a global network with many thousands of clients

schedule feasibility

means that a project can be implemented in an acceptable time frame

Legacy systems

older information systems that remain in use because they still function and are costly to replace

Business Support Systems

provide job-related information support to users at all levels of a company

Output

refers to electronic or printed information produced by the system

secuirty

refers to hardware, software, and procedural controls that safeguard and protect the system and its data from internal or external threats

enterprise computing

refers to information systems that support company-wide operations and data management requirements.

Input

refers to necessary data that enters the system, either manually or in an automated manner

Performance

refers to system characteristics, such as speed, volume, capacity, availability, and reliability.

information technology

refers to the combination of hardware, software, and services that people use to manage, communicate, and share information.

Process

refers to the logical rules that are applied to transform the data into meaningful information

Technical Feasibility

refers to the technical resources needed to develop, purchase, install, or operate the system

Logical model

shows what the system must do, regardless of how it will be implemented physically

Electronic Data Interchange (EDI)

the computer-to-computer exchange of business documents from a retailer to a vendor and back

software

the programs that control the hardware and produce the desired information or results

Data store

used in a DFD to represent data that the system stores because one or more processes need to use the data at a later time

Required modeling

where the analyst investigates business processes and documents what the new system must do to satisfy users