Construction Phase

In this phase, the main focus goes to the development of components and other features of the system being designed. This is the phase when the bulk of the coding takes place. In larger projects, several construction iterations may be developed in an effort to divide the use cases into manageable segments that produce demonstrable prototypes.

This phase produces the first external release of the software. Its conclusion is marked by the Initial Operational Capability Milestone.

Following are the engineering disciplines followed in this phase of the project lifecycle:

• Implementation Discipline

  The purposes of implementation are:

  • To define the organization of the code, in terms of implementation subsystems organized in layers.
  • To implement classes and objects in terms of components (source files, binaries, executables, and others).
  • To test the developed components as units.
  • To integrate the results produced by individual implementers (or teams), into an executable system.

Systems are realized through implementation of components. The process describes how you reuse existing components, or implement new components with well defined responsibility, making the system easier to maintain, and increasing the possibilities to reuse.

• Test Discipline

  The purposes of the Test discipline are:

  • To verify the interaction between objects.
  • To verify the proper integration of all components of the software.
  • To verify that all requirements have been correctly implemented.
  • To identify and ensure that defects are addressed prior to the deployment of the software.

The Rational Unified Process proposes an iterative approach, which means that you test throughout the project. This allows you to find defects as early as possible, which radically reduces the cost of fixing the defect. Tests are carried out along four quality dimensions reliability, functionality, application performance, and system performance. For each of these quality dimensions, the process describes how you go through the test lifecycle of planning, design, implementation, execution and evaluation.