Chapter 9

Page 1

Feasibility study

- To determine if a project is likely to be successful

Reasons a project may fail:

The budget may not be big enough or the cost of the project may be too high - not economically feasible

It would break laws about data protection and privacy - not legally feasible

Beyond what current hardware or algorithms can achieve - not technically feasible

A feasibility study is the first step of any project

Requirements specification

Requirements are the things that the final system needs to be able to do

The process of determining the requirements is called requirements elicitation

When the project is complete the system is tested against the requirements - this is called acceptance testing

Testing

This should take place continually during the coding process. After every module of code is written it should be tested to be certain it works.

Testing should take place in this order:

Destructive testing - is when testers try to cause a program to crash or behave unexpectedly

Alpha testing - is when the product is used within the company by people who haven't worked on the project

Beta testing - is when a small group of users from outside the software company use the software to see if they encounter any bugs or usability problems not picked up during the previous testing

Acceptance testing - is when the user tests the program against every requirement in the requirements specification. Once this is successful the project can be signed off

Black box testing - Sees the software as a black box with just inputs and outputs

White box testing - Analyses the structure and logic of the program

Documentation

Page 2

1. Describe the risks of failing to carry out a feasibility study (2)

The feasibility study's purpose is to decide whether a project is likely to be successful before it has started. By not carrying out a feasibility study you risk starting a project that cant succeed.

2. Explain why beta testing is important (2)

Beta testing is used be people outside of the company to identify the problems in a system and correct the problems as they are found.

3. Explain the purpose of technical documentation (2)

Technical documentation explains how the system works and user documentation explains how to use it.

4. Explain how extreme programming is likely to lead to high-quality code (3)

Extreme programming is likely to lead to high-quality code because of its use of pair programming, refactoring and having a representative of the user through out.

5. Explain why the spiral model would be a better choice than the waterfall life cycle model for a high-risk project (4)

The spiral model uses an iterative approach centred around risk. This means that the high risk issues can be dealt with first. In a high-risk project this is better to use than the waterfall life cycle because the project will be more likely to succeed after the high risk issues are dealt with. The waterfall life cycle just involves one stage being completed after another.