Oklahoma State University - MSIS4003 System Analysis and Design Exam 1

Systems Analysis and Design

A complex organizational process used to develop and maintain computer-based information systems used by a team of business and systems professionals

Sub-components of Systems Analysis

Methods, Techniques, Tools

Method

comprehensive, multi-step approaches to systems development that will guide your work and influence the quality of your final product

Technique

particular processes that you, as an analyst, will follow to help ensure that your work is well thought out,complete, and comprehensible to others on your project team.

Tool

typically computer programs that make it easy to use and benefit from techniques and to faithfully follow guidelines of the overall development methodology.

Application Software

computer software designed to support organizational functions or processes

Systems Analyst

organizational role most responsible for analysis and design of information systems

Traditional Method

Waterfall

Evolutionary Method

Agile

Advantages of Waterfall Method

Stages are distinct, fairly well defined, and completed in succession
Support documentation and requirements help developers to work autonomously
Allows for better understanding of the projected end date of the projec

Disadvantages of Waterfall Method

Spend a large amount of time creating documents that may become out-of-date very quickly
Feedback ignored, milestones lock in design specs even when conditions change
Limited user involvement(only in requirements phase

Advantages of Agile Method

Clients involved through entire process of development
Open to revisions and additions through lifetime of the project -high amount of flexibility
Deliver minimum viable product so client has usable software quickly

Disadvantages of Agile Method

Requires high amount of team collaboration and work
Start building the product without fully knowing how the entire solution will be realized
Lack of formalized documentation
No firm idea of scope and timeline until project near completion

Systems Development Life Cycle (SDLC) Phases

Planning
Analysis
Design
Implementation
Maintenance

Planning Phase

an organization's total information system needs are identified, analyzed, prioritized, and arranged

Analysis Phase

system requirements are studied and structured

Design Phase

a description of the recommended solution is converted into logical and then physical system specifications

Implementation Phase

the information system is coded, tested, installed and supported in the organization

Maintenance Phase

an information system is systematically repaired and improved

Logical Design

all functional features of the system chosen for development in analysis are described independently of any computer platform

Physical Design

the logical specifications of the system from logical design are transformed into the technology-specific details from which all programming and system construction can be accomplished

Evolutionary Design Types

CASE Tools
Rapid Application Development (RAD)
Agile Methodologies

Agile Methodologies

Adaptive rather than predictive
Emphasize people rather than roles
Self-adaptive processes

When To Use Agile Methodologies

If your project involves:
Unpredictable or dynamic requirements
Responsible and motivated developers
Customers who understand the process and will get involved

Top-Down Source

projects identified by top management or by a diverse steering committee.

Bottom-Up Source

project initiatives stemming from managers, business units, or the development group

Baseline Project Plan

A major outcome and deliverable
Contains the best estimate of a project's scope, benefits, costs, risks, and resource requirements

Steps to Assess Project Feasability

Economic
Technical
Operational
Scheduling
Legal and contractual
Political

Project Scope Statement

A document prepared for the customer
Describes what the project will deliver
Outlines at a high level all work required to complete the project

PSS Elements

Project objectives
Deliverables
Milestones
Technical requirements
Limits and exclusion
Reviews with customer

Customer

Sets the priority

Traditional Ways for Determining Requirements

Interviewing individuals
Interviewing groups
Observing workers
Studying business documents

Main Difference between Agile and Waterfall

Continual user involvement

Form

a business document that contains some predefined data and may include some areas where additional data are to be filled in

Report

a business document that contains only predefined data

Major Activities of System Implementation

Coding
Testing
Installation
Documentation
Training
Support

Static Testing

the code being tested is not executed

Dynamic Testing

execution of the code

Automated Testing

computer conducts the test.

Manual Testing

people complete the test.

Alpha Testing

user testing of a completed information system using simulated data

Beta Testing

user testing of a completed information system using real data in the real user environment

Direct Installation

changing over from the old system to a new one by turning off the old system when the new system is turned on

Installation Strategies

Direct Installation
Parallel Installation
Single-location installation
Phased Installation

Parallel Installation

running the old information system and the new one at the same time until management decides the old system can be turned off

Phased Installation

changing from the old information system to the new one incrementally, starting with one or a few functional components and then gradually extending the installation to cover the whole new system

Single-Location Installation

trying out an information system at one site and using the experience to decide if and how the new system should be deployed throughout the organization
Also known as location or pilot installation