Checkpoints: Supplementary Specifications

The following basic issues should be addressed to detail all requirements that are not specified within the use-case model:

• Functionality: What is the software supposed to do? This should include:
  • Validity checks on the inputs
  • General responses to abnormal situations, including: overflow, communication facilities, error handling and recovery
  • Effects of parameters
  • Relationship of outputs to inputs, including input/output sequences and formulas for input to output conversion
• External interfaces: How does the software interact with people, the system’s hardware, other hardware, and other software?
• Performance: What is the speed, availability, response time, recovery time of various software functions, etc.? Are both static and dynamic requirements included?
• Logical database requirements: Have all logical requirements been specified for any information that is to be placed into a database? This may include:
  • Types of information used by various functions
  • Frequency of use
  • Accessing capabilities
  • Data entities and their relationships
  • Integrity constraints
  • Data retention requirements
• Standards Compliance: Have all requirements derived from existing standard and regulations been specified? How will this be traced?
• Attributes: What are the reliability, availability, portability, correctness, maintainability, security, etc. considerations?
• Design constraints imposed on an implementation: Are there any required standards in effect, implementation language, policies for database integrity, resource limits, operating environment(s), etc.?