UNIT – II SOFTWARE REQUIREMENTS

1. What is cardinality in data modeling?

Cardinality in data modeling, cardinality specifies how the number of  occurrences of one object is related to the number of occurrences of another  object.

2. What does modality in data modeling indicates?

Modality indicates whether or not a particular data object must participate  in the relationship.

3. What is ERD?

Entity Relationship Diagram is the graphical representation of the object  relationship pair. It is mainly used in database applications.

4. What is DFD?

Data Flow Diagram depicts the information flow and the transforms that are applied on the data as it moves from input to output.

5. What does Level0 DFD represent?

Level 0 DFD is called as ‘fundamental system model’ or ‘context model’. In the context model the entire software system is represented by a single bubble with input and output indicated by incoming and outgoing arrows.

6. What is a state transition diagram?

State transition diagram is basically a collection of states and events. The events cause the system to change its state. It also represents what actions are to   be taken on the occurrence of particular event.

 7. Define Data Dictionary.

The data dictionary can be defined as an organized collection of all the data elements of the system with precise and rigorous definitions so that user and system analyst will have a common understanding of inputs, outputs, components of stores and intermediate calculations.

 8. What are the elements of Analysis model?

i. Data Dictionary

ii. Entity Relationship Diagram

iii. Data Flow Diagram

iv. State Transition Diagram

v. Control Specification

vi. Process specification.

9. What are functional requirements?

                        Functional requirements are” statements of services the system should provide how the system should react to particular input and how the system should behave in particular situation.

10. What are non functional requirements?

                        Non functional requirements are constraints on the services or functions offered by the system such as timing constraints, constraints on the development process, standards, etc……..

11. What is the outcome of feasibility study?

                        The outcome of feasibility study is the results obtained from the following questions:

·         Which system contributes to organizational objectives?

·          Whether the system can be engineered? Is it within the budget?

·         Whether the system can be integrated with other existing system?

12. What is meant by structural analysis?

                         The structural analysis is mapping of problem domain to flows and transformations. The system can be modeled by using Entity Relationship diagram, Data flow diagram and Control flow diagrams.