Ques : What is Identifying Components and their Interaction

 Ans : Identification Process

1. Functionality modeling: Component identification always starts by decomposing
   the business domain problem structure into a well-defined visual model. Data flow
   diagram is one of the most popular visual models to depict function oriented
   design.
   
2. Design module development: The next step is to convert individual elements in
   the DFD into a design module. During this process, the design modules need to be
   designed to ensure high cohesion and loose inter-module coupling. The modules
   that perform similar kind of functionalities and processes qualify for the main
   design module. Design modules would then become key function component.
   
3. Sub function development: The main functions need to be broken down into sub
   functions. Utilities such as, data validation, data conversion, information Jogging
   would be good candidates for sub-functions.
   
4. Interaction modeling: The input and output elements from DFD can be used to
   design the interactions between functions.
   
   
   

Component and Stage Mapping
The following table indicates the component/association identified at each level of the
process:

          Stage                                                                                       Component! Association
Functional modeling                                                                                 Data flow diagram
Design module development                                                                    High level function
Sub function development                                                                            Sub functions
Interaction modeling                                                                               Input and output data