Non-Functional Testing
This section is based upon the testing of the application from its
non-functional attributes. Non-functional testing of Software involves
testing the Software from the requirements which are non functional in
nature related but important a well such as performance, security, user
interface etc.
Some of the important and commonly used non-functional testing types are mentioned as follows:
Performance Testing
It is mostly used to identify any bottlenecks or performance issues
rather than finding the bugs in software. There are different causes
which contribute in lowering the performance of software:
- Network delay.
- Client side processing.
- Database transaction processing.
- Load balancing between servers.
- Data rendering.
Performance testing is considered as one of the important and mandatory testing type in terms of following aspects:
- Speed (i.e. Response Time, data rendering and accessing)
- Capacity
- Stability
- Scalability
It can be either qualitative or quantitative testing activity and can be divided into different sub types such as
Load testing and
Stress testing.
Load Testing
A process of testing the behavior of the Software by applying maximum
load in terms of Software accessing and manipulating large input data.
It can be done at both normal and peak load conditions. This type of
testing identifies the maximum capacity of Software and its behavior at
peak time.
Most of the time, Load testing is performed with the help of
automated tools such as Load Runner, AppLoader, IBM Rational Performance
Tester, Apache JMeter, Silk Performer, Visual Studio Load Test etc.
Virtual users (VUsers) are defined in the automated testing tool and
the script is executed to verify the Load testing for the Software. The
quantity of users can be increased or decreased concurrently or
incrementally based upon the requirements.
Stress Testing
This testing type includes the testing of Software behavior under
abnormal conditions. Taking away the resources, applying load beyond the
actual load limit is Stress testing.
The main intent is to test the Software by applying the load to the
system and taking over the resources used by the Software to identify
the breaking point. This testing can be performed by testing different
scenarios such as:
- Shutdown or restart of Network ports randomly.
- Turning the database on or off.
- Running different processes that consume resources such as CPU, Memory, server etc.
Usability Testing
This section includes different concepts and definitions of Usability
testing from Software point of view. It is a black box technique and is
used to identify any error(s) and improvements in the Software by
observing the users through their usage and operation.
According to Nielsen, Usability can be defined in terms of five
factors i.e. Efficiency of use, Learn-ability, Memor-ability,
Errors/safety, satisfaction. According to him the usability of the
product will be good and the system is usable if it possesses the above
factors.
Nigel Bevan and Macleod considered that Usability is the quality
requirement which can be measured as the outcome of interactions with a
computer system. This requirement can be fulfilled and the end user will
be satisfied if the intended goals are achieved effectively with the
use of proper resources.
Molich in 2000 stated that user friendly system should fulfill the
following five goals i.e. Easy to Learn, Easy to Remember, Efficient to
Use, Satisfactory to Use and Easy to Understand.
In addition to different definitions of usability, there are some
standards and quality models and methods which define the usability in
the form of attributes and sub attributes such as ISO-9126, ISO-9241-11,
ISO-13407 and IEEE std.610.12 etc.
UI vs Usability Testing
UI testing involves the testing of Graphical User Interface of the
Software. This testing ensures that the GUI should be according to
requirements in terms of color, alignment, size and other properties.
On the other hand Usability testing ensures that a good and user
friendly GUI is designed and is easy to use for the end user. UI
testing can be considered as a sub part of Usability testing.
Security Testing
Security testing involves the testing of Software in order to
identify any flaws ad gaps from security and vulnerability point of
view. Following are the main aspects which Security testing should
ensure:
- Confidentiality.
- Integrity.
- Authentication.
- Availability.
- Authorization.
- Non-repudiation.
- Software is secure against known and unknown vulnerabilities.
- Software data is secure.
- Software is according to all security regulations.
- Input checking and validation.
- SQL insertion attacks.
- Injection flaws.
- Session management issues.
- Cross-site scripting attacks.
- Buffer overflows vulnerabilities.
- Directory traversal attacks.
Portability Testing
Portability testing includes the testing of Software with intend that
it should be re-useable and can be moved from another Software as well.
Following are the strategies that can be used for Portability testing.
- Transferred installed Software from one computer to another.
- Building executable (.exe) to run the Software on different platforms.
Portability testing can be considered as one of the sub parts of
System testing, as this testing type includes the overall testing of
Software with respect to its usage over different environments. Computer
Hardware, Operating Systems and Browsers are the major focus of
Portability testing. Following are some pre-conditions for Portability
testing:
- Software should be designed and coded, keeping in mind Portability Requirements.
- Unit testing has been performed on the associated components.
- Integration testing has been performed.
- Test environment has been established.
Installation Testing: -
It is a type of testing in which one will install the application in to the environment by following the guide lines provided in the installation document and if the installation is successful then he will come a conclusion that the given guide lines are correct other wise he will come to a conclusion that the given guidelines are not correct.
