Software requirements specification
- 1. Presented by M.LAVANYA, M.SC (CS & IT) NADAR SARASWATHI COLLEGE OF ARTS & SCIENCE, THENI.
- 2. INTRODUCTION The goal of the software requirement definition is to completely and consistently specifies the technical requirements for the software product. Software requirements specification is based on the system specification high level requirements specified during initial planning are elaborated.
- 3. SOFTWARE REQUIREMENTS SPECIFICATION Format of a Software requirements specification Section 1: product overview and summary. Section 2: development , operating and maintenance environments. Section 3: external interfaces data flow. Section 4: functional requirements. Section 5: performance requirements. Section 6: exception handling.
- 4. Section 7:early subsets and implementation priorities. Section 8: foreseeable modification and enhancements. Section 9: acceptance criteria. Section 10: design hints and guidelines. Section 11: cross-reference index. Section 12: glossary of terms.
- 5. Section 1 & 2: The requirements documents present and overview of product features and summarize the processing environments for development , operation and maintenance of the product.
- 6. Section 3: Include user displays and report formats , a summary of user commands and report options , data flow diagram and data dictionary.
- 7. Data flow diagram specify data sources and data sinks , data stores , transformations to be performed. Data and flow of data between sources , sinks , transformation and stores. Data source and data sinks are depicted by shaded rectangles , transformations by ordinary rectangles and data stores by open ended rectangles.
- 8. AN INFORMAL DATA FLOW DIAGRAM
- 9. A entities in a data dictionary include the name of the data item and attributes such as the data flow diagrams where it is used , it’s purpose derived from , it’s sub items .
- 10. Section 4: Functional requirements are expressed in relational and state-oriented notation that specific relationships among inputs, actions and outputs.
- 11. Section 5: Performance characteristics such as response time for various activities , processing time for various processes , throughput, primary and secondary memory constraints , telecommunications bandwidth
- 12. Section 6: Exception handling include the actions to be taken and messages to be displayed to undesired situations or events . Categories of possible exceptions include temporary , permanent resources, incorrect inconsistent values and parameters.
- 13. Section 7: Early subsets and implementations priorities for the system under development . Product to be planned in three versions: prototype , modest and enhanced version The customer may desire delivery of subset capabilities and the successive versions can increasing level of capabilities.
- 14. Section 8: Foreseeable modifications and enhancements that may be incorporated in to the product following initial product release are specified in the product requirements.
- 15. Section 9: Acceptance criteria specify functional and performance tests that must be performed and standards to source code internal and external documentation
- 16. Section 10: Software requirements specification contains design hints and guidelines. The requirements specification is primary with functional and performance aspects of a software product.
- 17. Section 11: A cross-reference directory should be provided to index specific paragraph number in the software requirements specification to specific paragraphs in the system definition.
- 18. Section 12: Software requirements specification provides definitions of terms that may be unfamiliar to the customer and product developers.
- 19. DESIRABLE PROPERTIES: There are a number of desirable properties that a software requirements specification should posses . In particular , a requirements documents should be: Correct Complete Consistent Unambiguous Functional Verifiable Traceable Easily changed
- 20. THANK YOU