Component Level Design - Definition, why it is important and what are the steps?

When the first iteration of architectural design is completed, component level design comes into picture. Intent of this phase is to translate the design model into operational software. The internal data structures and processing details of each component are not represented at a level of abstraction that is close to code. Component level design defines the data structures, algorithms, interface characteristics, and communication mechanisms allocated to each software component. A software engineer performs component level design.

Component level design is important because it is necessary to determine whether the software will work before you build it. The component level design represents the software in a way that allows you to review the details of the design for correctness and consistency with earlier design representations. It also provides a means for assessing whether data structures, interfaces and algorithms will work.

It is possible to represent component level design using a programming language. Component level design can also be represented by using some intermediate representation that can be translated easily into source code.

Define Component?
A component is a modular building block for computer software. Components should communicate and collaborate with other components as they reside within the software architecture. The meaning of component will differ depending on the point of view of software engineer using it. There are three different views of defining component :
- An Object oriented view
- The Conventional view
- A Process-related view

Steps in Component Level Design
- Design representations of data, architecture, and interfaces form the foundation of component level design.
- Class definition or processing narrative for each component is translated into detailed design that makes use of diagrammatic or text based forms that specify internal data structures, local interface detail, and processing logic.
- The procedural design is specified using a set of structured programming constructs.