This document discusses software evolution, verification, and validation. It defines software evolution as the process of developing software and updating it over time for reasons like adding new features or removing obsolete functionality. Verification ensures the product is developed correctly by checking requirements, design, and code, while validation ensures the right product is built by testing it meets specifications and customer needs. The key difference is that verification checks the development process, while validation checks the final product.

1. SOFTWARE EVOLUTION,
VERIFICATION & VALIDATION
By
M.ARCHANA
II-Msc(CS)
Department of CS & IT
Nadar Saraswathi College of
Arts and Science

2. THIS INCLUDES:
Software Evolution
The necessity of Software evolution
Laws used for Software Evolution
Introduction to Verification and Validation
Verification testing
Validation testing
Difference between verification and
validation testing

3. SOFTWARE EVOLUTION:
Software Evolution is a term which refers to the process of
developing software initially, then timely updating it for
various reasons, i.e., to add new features or to remove
obsolete functionalities etc.
The evolution process includes fundamental activities of
change analysis, release planning, system implementation and
releasing a system to customers

4. THE NECESSITY OF SOFTWARE
EVOLUTION:
Environment change
Errors and bugs
Security risks

5. LAWS USED FOR SOFTWARE
EVOLUTION:
1. Law of continuing change:
This law states that any software system that
represents some real world reality undergoes
continuous change or become progressively less
useful in that environment.

6. CONT.,
2. Law of increasing complexity:
As an evolving program changes, its structure becomes more
complex unless effective efforts are made to avoid this
phenomenon.
3. Law of conservation of organization stability:
Over the lifetime of a program, the rate of development of
that program is approximately constant and independent of
the resource devoted to system development

8. INTRODUCTION:
Verification and Validation is the process of investigating that a software system
satisfies specifications and standards and it fulfills the required purpose.
Barry Boehm described verification and validation as the following:
Verification: Are we building the product right?
Validation: Are we building the right product?

9. VERIFICATION:
Verification is the process of checking that a software achieves its
goal without any bugs.
It is the process to ensure whether the product that is developed is
right or not.
It verifies whether the developed product fulfills the requirements
that we have.
Verification is Static Testing.

10. Note: Verification is followed by Validation

11. VALIDATION:
Validation is the process of checking whether the software product
is up to the mark or in other words product has high level
requirements.
It is the process of checking the validation of product i.e. it checks
what we are developing is the right product. it is validation of
actual and expected product.
Validation is the Dynamic Testing.

12. CONT.,
Activities involved in validation:
1. Black box testing
2. White box testing
3. Unit testing
4. Integration testing

14. VERIFICATION TESTING:
Verification testing includes different activities such as business
requirements, system requirements, design review, and code
walkthrough while developing a product.
It is also known as static testing, where we are ensuring that
"we are developing the right product or not".
And it also checks that the developed application fulfilling all
the requirements given by the client.

16. VALIDATION TESTING:
Validation testing is testing where tester performed functional
and non-functional testing.
Here functional testing includes Unit Testing (UT),
Integration Testing (IT) and System Testing (ST), and non-
functional testing includes User acceptance testing (UAT).
Validation testing is also known as dynamic testing, where
we are ensuring that "we have developed the product right”.
And it also checks that the software meets the business needs
of the client.

18. DIFFERENCE BETWEEN VERIFICATION
AND VALIDATION TESTING:
Verification
 We check whether we are developing
the right product or not.
 Verification is also known as static
testing.
 Verification is done before the
validation testing.
Validation
 We check whether the developed
product is right
 Validation is also known as dynamic
testing.
 After verification testing, validation
testing takes place.

19. CONT.,
Verification
 Verification includes different
methods like Inspections, Reviews,
and Walkthroughs
 It is a process of checking the work-
products (not the final product) of a
development cycle to decide whether
the product meets the specified
requirements
Validation
 Validation includes testing like
functional testing, system testing,
integration, and User acceptance
testing
 It is a process of checking the
software during or at the end of the
development cycle to decide whether
the software follow the specified
business requirements.

20. CONT.,
Verification
 Quality assurance comes under
verification testing.
 The execution of code does not
happen in the verification testing.
 In verification testing, we can find the
bugs early in the development phase
of the product
Validation
 Quality control comes under
validation testing.
 In validation testing, the execution of
code happens.
 In the validation testing, we can find
those bugs, which are not caught in
the verification process

21. CONT.,
Verification
 Verification testing is executed by the
Quality assurance team to make sure
that the product is developed
according to customers' requirements
 In this type of testing, we can verify
that the inputs follow the outputs or
not
Validation
 Validation testing is executed by the
testing team to test the application.
 In this type of testing, we can validate
that the user accepts the product or not.