it is related from software testing

1. On
Software testing
SUBMITED BY
LOKESH GUPTA
MTECH S.E

2. Software testing is performed to verify that the
completed software package functions according to
the expectations defined by the Requirements/
specifications. The overall objective to not to find
every software bug that exists, but to uncover
situations that could negatively impact the
customer, usability and/or maintainability.

3. Two process involves in software testing
Validation
Verification
Validation :
Validation uses methods like black box
(functional) testing, gray box testing, and white box
(structural) testing etc.
Validation is to check whether software meets the
customer expectations and requirements

4. Verification :
Verification uses methods like inspections,
reviews, walkthroughs, and Desk-checking etc.
Verification is to check whether the software
conforms to specifications.
Verification is done by development team to
provide that the software is as per the specifications
in the SRS document.

5. Figure1.1: Verification and Validation

6.  Testing can be used to show the presence of errors,
but never to show their absence. It can only
identify the known issues or errors. It gives no idea
about defects still uncovered. Testing cannot
guarantee that the system under test is error free.
 Testing provides no help when we have to make a
decision to either "release the product with errors for
meeting the deadline" or to "release the product late
compromising the deadline.

7. Testing cannot establish that a product functions
properly under all conditions but can only establish
that it does not function properly under specific
conditions.
Software testing does not help in finding root
causes which resulted in injection of defects in the
first place. Locating root causes of failures can help
us in preventing injection of such faults in future.

8. Test cases are developed using various test
techniques to achieve more effective testing. By this,
software completeness is provided and conditions of
testing which get the greatest probability of finding
errors are chosen. So , testers do not guess which test
cases to chose, and test techniques enable them to
design testing conditions in a systematic way.

9. Software can be tested in two ways, in another words,
one can distinguish two different methods:
1. Black box testing
2. White box testing
Black box testing: The technique of testing without
having any knowledge of the interior workings of the
application is Black Box testing. The tester is
oblivious to the system architecture and does not
have access to the source code.

10. FiFigure 1.2: Black Box Testing

11. when performing a black box test, a tester will
interact with the system's user interface by
providing inputs and examining outputs without
knowing how and where the inputs are worked
upon.
Test case design input and output
Equivalent Partitioning
Boundary Value Analysis

12. White box testing is the detailed investigation of
internal logic and structure of the code. White box
testing is also called glass testing or open box testing.
In order to perform white box testing on an
application, the tester needs to possess knowledge of
the internal working of the code.
The tester needs to have a look inside the source code
and find out which unit/chunk of the code is
behaving inappropriately.

13. Figure1.3:White box testing

14. White box testing
Finding the following errors area:
Independence path check
Data structure
Cyclomatic complexity

15. A
CC
B
2
3
D
1
F
E

16. Cyclomatic Complexity formula V(g):E-N+2
Where E=edge
N=node
V(g) = E-N+2
=7-6+2
=3
2) =P+1 p(predicate node)
=2+1=3
3)No of regions=3