OBJECTIVE

The objective of the Design Phase is to transform the detailed, defined requirements into complete, detailed specifications for the system to guide the work of the Development Phase. The decisions made in this phase address, in detail, how the system will meet the defined functional, physical, interface, and data requirements. Design Phase activities may be conducted in an iterative fashion, producing first a general system design that emphasizes the functional features of the system, then a more detailed system design that expands the general design by providing all the technical detail.

TASKS AND ACTIVITIES

The following tasks are performed during the Design Phase.

1.  Establish the Application Environment

Identify/specify the target, the development and the design and testing environment. How and where will the application reside. Describe the architecture where this application will be developed and tested and who is responsible for this activity.

2.  Design the Application

In the system design, first the general system characteristics are defined. The data storage and access for the database layer need to be designed. The user interface at the desktop layer needs to be designed. The business rules layer or the application logic needs to be designed.

Establish a top-level architecture of the system and document it. The architecture shall identify items of hardware, software, and manual-operations. All the system requirements should be allocated among the hardware configuration items, software configuration items, and manual operations.

Transform the requirements for the software item into an architecture that describes its top-level structure and identifies the software components. Ensure that all the requirements for the software item are allocated to its software components and further refined to facilitate detailed design. Develop and document a top-level design for the interfaces external to the software item and between the software components of the software item.

3.  Conduct Critical Design Review

The Project Manager and System Developers conduct the critical design review and approve/disapprove the project into the Development Phase. This review is conducted at the end of the Design Phase and verifies that the final system design adequately addresses all functional, security, and technical requirements and is consistent with the overall architecture.