CS403 1st assignment announced

Q. Draw a Context as well as Level 0 Data Flow Diagram (DFD) of any DVD rental System.

Guidelines / Requirements:

The context level diagram must contain a major process and external entities.

Level 0 diagram must consist of major functions and should work as follows:


Ø There should be 2 streams, or flows of data.

· The customer request to rent a DVD, system check the availability from DVD store, and then system get the details of customer

· Bill will be generated on behalf of the detail of DVD and handed over to customer.

And finally customer gets the DVD after payment in cash.


Purposes:

Ensure that you can analyze existing manual system and can draw Data Flow Diagrams of any proposed system.

Before Starting you should study and understand:
Rules for drawing DFDs.
Differentiate different levels of DFDs.

solutions:

Context Diagrams at the Project Level

It illustrates the business system, not the computer system. It shows the input and output data flows to a central process that represents the business system under analysis. The context diagram defines the scope of the project.

Project Scope

A Context Diagram confines project scope to an agreed limit by obtaining agreement from the customer on the data flows that are included in the scope of a project. The Context Diagram focuses on relationships with external entities and identifies the information that is exchanged between these external entities and the business system under review. The external entities themselves are outside the scope of the project but the data flows between the entities and the business system are within the project scope.

Level of Detail

The Context Diagram at the project level is the root of the Functional Decomposition at the conceptual level of detail. The Context Diagram is level zero of the decomposition.

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DFD LEVEL O DIAGRAM FOR DVD ...

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DVD Rental System - 0 DFD





Context Diagram

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