What do you mean by formal specification? Explain.

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- Formal specification is a part of a more general collection of techniques that are known as the "formal method".

Example:- COMP313"Formal methods" (These are all based on the mathematical representation and analysis of software.)

- Formal methods include :

  • Formal specification
  • Specification analysis and proof 
  • Transformation development
  • Program verification
Types of formal specification 
a) Behavioral Specification
- Behavioral specification describes constraints on the behavior of the implementation.
- Example:- functionality, safety, security, performance, etc
 
b) Structural specification 
- It describes constraints on the internal composition of implementation.
- Example:- Module interconnection, dependence relation

Importance of Formal Specification
-  Formal Specification involves investing more effort in the early phases of software development.
 - To explain why formal specification techniques help to discover problems in system requirements.
- To describe the use of:-
  ° algebraic technique(for interface specification) &
  °  model-based techniques( for behavioral specification)
- To introduced Abstract State Machine Model(ASMM)
- Formal Specification reduces requirements error as it forces a detailed analysis of the requirements.
 

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