2.3 Software Development

Analysis of requirements Design Development Testing Implementation Evaluation & Maintenance

Alpha testing is carried out by the software developers to identify and fix bugs. Beta testing is carried out by end users and their feedback is used to inform the next stage of development.

Tracing through and testing all possible routes of the program based on its internal structure.

Tracing through possible inputs and outputs of the software to identify bugs.

waterfall lifecycle agile methodologies e.g. extreme programming spiral model rapid application development

A software development methodology where a series of stages are completed in sequence meaning one stage can’t begin before the previous stage is completed. End users are involved in defining the initial requirements during the analysis stage but have little input afterwards until evaluation. Analysis Design Implementation Evaluation Maintenance

Low-risk projects that require little user input such as general purpose software with static requirements.

• straight forward to manage • requirements are clearly defined • clearly documented

• limits changing requirements throughout development • lack of flexibility • requirements defined at the start must be clear and correct • limited user involvement • no risk analysis

A collection of methodologies which aim to improve the flexibility of software development and adapt to changes in user requirements quickly.

problem is broken down into sections that are developed in parallel prototypes are developed and improved in an iterative manner less focus on documentation and more focus on user satisfaction

A software development methodology that focuses on good quality code by having a pair of programmers develop each section of the program. It is an agile paradigm where development responds to changes in user requirements and prototypes are constantly created and reviewed to inform another iteration.

high quality code end user heavily involved adapts to new requirements

difficult to produce high quality documentation pair of programmers must work well together and communicate effectively to avoid bugs changes in requirements may slow down the development process

A software development methodology built on 4 key stages with the focus of effectively managing high risk projects. • determine objectives • pinpointing/mitigating risks • development/testing/implement • evaluation/plan for next iteration if the project is found to be too risky at any point, the process is terminated

minimises risk suits large scale projects client feedback considered features added incrementally on each iteration

time consuming expensive requires large team and thorough risk assessment and client feedback

An iterative software development methodology where a partially-functioning prototype is created and evaluated with the feedback being used to inform the next iteration. This is continued until the prototype becomes the final product.

intitial requirements can be unclear prototype produced quickly entire process takes minimal amounts of time`

code may be inefficient due to continuous additions and changes speed > quality initial prototype may not represent the final product very well