System Development Life Cycle

The basic elements of the system development life cycle are as follows;

• Plan

Those developing the new system will go out to the end user environment to discover what key functions the new system is expected to have. Constraints such as space, cost and legislate will supplement user needs at this stage. The initial analysis is validated with managers and users to check that the problem and context are fully understood.

• Design and build

A variety of designs or solutions may be produced and evaluated. Trade-offs may be made between short-term and long-term considerations.

• Implement

Occurs once the best design is chosen and agreed, the software construction begins. The newly developed system now needs to be tested to ensure that the system supports the desired functions and provides an acceptable performance.

• Monitor

Monitoring means keeping a watching brief and dealing with maintenance and other issues as they arise such as errors not discovered during the testing phase to improve the systems services.

It is good practice to have development lifecycle documents - these should include security.

Life cycle models include the following

- waterfall, rapid prototyping, incremental and spiral.