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Outline the structure/format of SRS.

The Standard Structure of a Software Requirements Specification (SRS)​

A Software Requirements Specification (SRS) typically follows a standardized structure to ensure all necessary information is included in a logical and accessible format. The following outline presents a comprehensive structure based on IEEE 830 standard (a widely recognized standard for SRS documents) with modern adaptations:

1. Introduction​

1.1 Purpose​

  • States the purpose of the SRS document and its intended audience

1.2 Scope​

  • Identifies the software product(s) to be produced
  • Explains what the software will and will not do
  • Describes the application of the software being specified

1.3 Definitions, Acronyms, and Abbreviations​

  • Provides definitions of all terms, acronyms, and abbreviations required to properly interpret the SRS

1.4 References​

  • Lists all documents referenced in the SRS
  • Includes complete reference information (title, author, date, source)

1.5 Overview​

  • Describes contents and organization of the remainder of the document

2. Overall Description​

2.1 Product Perspective​

  • Explains the context and origin of the product being specified
  • Describes how it relates to other products
  • Includes system interfaces, user interfaces, hardware interfaces, software interfaces, and communication interfaces
  • May include system architecture diagrams

2.2 Product Functions​

  • Provides a summary of the major functions the software will perform
  • Often presented as a use case diagram or list of features

2.3 User Characteristics​

  • Describes the general characteristics of the intended users
  • Includes technical expertise, education level, and experience

2.4 Constraints​

  • Lists general constraints that will affect development options
  • Includes regulatory policies, hardware limitations, interfaces to other applications, security requirements, etc.

2.5 Assumptions and Dependencies​

  • Lists factors that affect the requirements stated in the SRS
  • Includes assumptions about the environment, users, and third-party components

2.6 Apportioning of Requirements​

  • Identifies requirements that may be delayed until future versions of the system

3. Specific Requirements​

This section contains all the software requirements at a level of detail sufficient for designers to design a system to satisfy those requirements and for testers to test that the system satisfies those requirements.

3.1 External Interface Requirements​

3.1.1 User Interfaces​

  • Screen layouts, content organization, and navigation paths
  • UI standards or style guides to be followed
  • GUI components and their behavior

3.1.2 Hardware Interfaces​

  • Logical and physical characteristics of interfaces between software and hardware

3.1.3 Software Interfaces​

  • Connections with other software components
  • APIs, external services, and data exchanges

3.1.4 Communications Interfaces​

  • Communication protocols, security mechanisms, data transfer rates

3.2 Functional Requirements​

  • Organized by user class, feature, object, stimulus, functional hierarchy, or combinations of these
  • Each functional requirement should include:
    • Inputs
    • Processing
    • Outputs
    • Purpose
    • Error handling

3.3 Non-Functional Requirements​

3.3.1 Performance Requirements​

  • Response times, throughput, capacity, scalability

3.3.2 Security Requirements​

  • Authentication, authorization, data integrity, privacy

3.3.3 Reliability Requirements​

  • Availability, failure rate, recoverability, predictability

3.3.4 Usability Requirements​

  • Learnability, efficiency of use, memorability, error frequency and severity

3.3.5 Maintainability Requirements​

  • Modularity, modifiability, testability, extensibility

3.3.6 Portability Requirements​

  • Adaptability to different environments, installability

3.4 Data Requirements​

3.4.1 Data Models​

  • Entity relationship diagrams or data dictionary

3.4.2 Data Storage Requirements​

  • Database types, data retention periods

3.4.3 Data Migration Requirements​

  • If migrating from an existing system

4. Supporting Information​

4.1 Appendices​

  • Sample input/output formats, descriptions of cost analysis studies, supporting or background information

4.2 Index​

  • Terms and their locations in the document

4.3 Change History​

  • Records of changes made to the SRS

This structure ensures that all aspects of the software requirements are documented in a comprehensive, organized manner that facilitates understanding, implementation, and verification of the system. The specific content and level of detail may vary based on the project's complexity, criticality, and organizational standards.