THE SYSTEMS LIFE CYCLE ANALYSE DESIGN IMPLEMENT MAINTENANCE IDENTIFY/INVESTIGATE

2.Analyse The Problem 3. Design A Solution 4.Implement Your solution 5. Maintain the solution 1.Identify/Investigate problem

Identify/Investigate problem 1. How does the current system operate 2. What does the current system not do 3. What should the new system be able to do 4. What are some alternative solutions 5. A recommended course of action

If the Identification recommends that the project can go ahead: 1.Make out a list of Objectives/Criteria 2.Begin the Analysis

L is t of Objectives/Criteria These should be kept simple and should be referred to throughout the coursework to ensure you are achieving what you set out to do eg. 游 The output must be easy to read and understand 游 Test the solution using suitable test data 游 Produce a template that can be re used

Analyse The Problem Examine what problems exist within the current system by asking questions What is being done now ? Why is it being done ? Who is doing it ? How is it being done ?

Questionnaires Interviews Observation Analyse The Problem Fact-finding methods used to gather information Examining Docs

The investigation is used to produce a detailed description of the current system including the use of Data Flow Diagrams and Systems Flowcharts See page 216 to 219 of text

What are the drawbacks of this solution ? How long will development take ? Design A Solution What hardware does the solution require ? What benefits does this new solution offer ? How much will this solution cost ? Identify the alternative possible solutions

Design A Solution Input Output Data Storage User Interface Back up procedures Security Procedures Test Plan Having identified the best solution produce a detailed design specification

Create data files Set up validation checks Enter enough data to test the system Implement A solution Set up the system so that it matches the design specification Create input/output screens Set up the user interface Set up system security

Extreme data - data that lies at the boundaries of acceptable input Normal data - expected during day to day use Implement A solution When testing the system use the plan prepared during the design stage Erroneous data - data that lies outwith the boundaries

Phased Implementation - Introduce the new system in smaller parts Direct Implementation - Instantaneous change from old to new system. Quick but very disruptive if errors found Implement A solution It is now possible to install the new system Parallel Implementation - Run both systems simultaneously over a period. Longer to operate. No disruption from errors

Implement A solution Finally, documentation must be produced for the system Technical Documentation User Documentation

Screen Layouts and UI Designs Implement A solution Technical Documentation System Design Specification Flowcharts Description of the system The Test Plan

Additional Support [Help Lines] Implement A solution User Documentation Minimum System requirements Loading Instructions Meaning of Error Messages Operating instructions

Maintenance Some time after installation, a new system may need to be changed to satisfy the needs of the user to correct problems to improve the system

The solution to each problem must be evaluated to check it’s success Evaluation Is the PROBLEM solved ? Have the Objectives/criteria been met ? Did the test data work ? How can the system be improved ?

Chapter 10 pgs gives a detailed breakdown of the requirements to be met for your coursework projects