The difference between a DFD for the structured paradigm and a functional model relates to data stores.

In the DFD, data stores correspond to files or databases.

In the functional model, data stores can be classes (identified by a name with initial letter capitalized, such as Elevator) or non-classes (identified by a name in upper-case, such as REQUEST).

An example of functional model for the "student" class of the online test system.

The design decision is whether to convert the data stores that are NOT classes, into classes.

Class Discussion: Use the above procedure to determine the classes, their attributes and their interactions for the term project.