Task $1$: Data Flow Diagrams $($DFD$)$

AutoParts Superstore sells a wide range of Japanese car spare parts. When customers place

orders on the company's website, the system checks to see if the items are in stock in the

warehouse. The system issues a status message to the customer for out$-$of$-$stock items and

generates a shipping order for available items to the accounting department. A bill is sent to the

customer, and when the customer has paid, the system sends an order confirmation to the

warehouse and the accounting department. When the order is shipped, the warehouse

generates a shipping confirmation to update stock and the system produces an inventory report

handled by the accounting department.

This is the Context Diagram:

Because it is the highest$-$level DFD$,$ the context diagram contains process $0,$ which represents

the entire information system, but does not show the internal workings $[1].$

Students Tasks

$1.$

$2.$

$3.$

Describe the next level of detail inside the order system process $0$ by creating a DFD named Diagram $0.$ This should repeat the entities and data flows that appear in the context diagram and show additional processes that must be named and numbered.

Decompose any one process from Diagram $0$ and draw a lower$-$level diagram $($called Diagram $1$ or Diagram $3$ etc.$).$

$$ Give your decomposed processes unique names and reference numbers $($levelling$).$ Pages $155-158$ in your course textbook explain this in detail $[1].$

Check if the diagrams are leveled and balanced correctly.

$$ Balanced means that, ignoring internal data flows and only counting the data flows to and from external entities, the same input and output data flows in the parent diagram are maintained in the child DFD$.$

$$ Leveled means that each internal process is numbered to show that it is a child of the parent process $(1\mathrm{.}1,1\mathrm{.}2,1\mathrm{.}3$ etc.$).$

$$ Use your imagination for any additional user or system requirements you think are necessary for the design.