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Verification Techniques
There are many different verification techniques but they all basically fall into 2 major categories - dynamic testing and static testing.
* Dynamic testing - Testing that involves the execution of a system or component. Basically, a number of test cases are chosen, where each test case consists of test data. These input test cases are used to determine output test results. Dynamic testing can be further divided into three categories - functional testing, structural testing, and random testing.
* Functional testing - Testing that involves identifying and testing all the functions of the system as defined within the requirements. This form of testing is an example of black-box testing since it involves no knowledge of the implementation of the system.
* Structural testing - Testing that has full knowledge of the implementation of the system and is an example of white-box testing. It uses the information from the internal structure of a system to devise tests to check the operation of individual components. Functional and structural testing both chooses test cases that investigate a particular characteristic of the system.
* Random testing - Testing that freely chooses test cases among the set of all possible test cases. The use of randomly determined inputs can detect faults that go undetected by other systematic testing techniques. Exhaustive testing, where the input test cases consists of every possible set of input values, is a form of random testing. Although exhaustive testing performed at every stage in the life cycle results in a complete verification of the system, it is realistically impossible to accomplish.
* Static testing - Testing that does not involve the operation of the system or component. Some of these techniques are performed manually while others are automated. Static testing can be further divided into 2 categories - techniques that analyze consistency and techniques that measure some program property.
* Consistency techniques - Techniques that are used to insure program properties such as correct syntax, correct parameter matching between procedures, correct typing, and correct requirements and specifications translation.
* Measurement techniques - Techniques that measure properties such as error proneness, understandibility, and well-structuredness
There are many different verification techniques but they all basically fall into 2 major categories - dynamic testing and static testing.
* Dynamic testing - Testing that involves the execution of a system or component. Basically, a number of test cases are chosen, where each test case consists of test data. These input test cases are used to determine output test results. Dynamic testing can be further divided into three categories - functional testing, structural testing, and random testing.
* Functional testing - Testing that involves identifying and testing all the functions of the system as defined within the requirements. This form of testing is an example of black-box testing since it involves no knowledge of the implementation of the system.
* Structural testing - Testing that has full knowledge of the implementation of the system and is an example of white-box testing. It uses the information from the internal structure of a system to devise tests to check the operation of individual components. Functional and structural testing both chooses test cases that investigate a particular characteristic of the system.
* Random testing - Testing that freely chooses test cases among the set of all possible test cases. The use of randomly determined inputs can detect faults that go undetected by other systematic testing techniques. Exhaustive testing, where the input test cases consists of every possible set of input values, is a form of random testing. Although exhaustive testing performed at every stage in the life cycle results in a complete verification of the system, it is realistically impossible to accomplish.
* Static testing - Testing that does not involve the operation of the system or component. Some of these techniques are performed manually while others are automated. Static testing can be further divided into 2 categories - techniques that analyze consistency and techniques that measure some program property.
* Consistency techniques - Techniques that are used to insure program properties such as correct syntax, correct parameter matching between procedures, correct typing, and correct requirements and specifications translation.
* Measurement techniques - Techniques that measure properties such as error proneness, understandibility, and well-structuredness
| Functionality (exterior quality) | Engineering (interior quality) | Adaptability (future quality) |
| Correctness | Efficiency | Flexibility |
| Reliability | Testability | Reusability |
| Usability | Documentation | Maintainability |
| Integrity | Structure |
Typical Software Quality Factors
We can not test quality directly, but we can test related factors to make quality visible. Quality has three sets of factors -- functionality, engineering, and adaptability. These three sets of factors can be thought of as dimensions in the software quality space. Each dimension may be broken down into its component factors and considerations at successively lower levels of detail. Table 1 illustrates some of the most frequently cited quality considerations. Tests with the purpose of validating the product works are named clean tests, or positive tests. The drawbacks are that it can only validate that the software works for the specified test cases.
Why testing is important?
TestingMantra.Com presents software testing as a practical engineering activity, essential to producing high-quality software. It is designed to be used as the primary website in either an undergraduate or graduate course on software testing, as a supplement to a general course on software engineering or data structures, and as a resource for software test engineers and developers.
Software bugs will almost always exist in any software module with moderate size: not because programmers are careless or irresponsible, but because the complexity of software is generally intractable -- and humans have only limited ability to manage complexity. It is also true that for any complex systems, design defects can never be completely ruled out.
Discovering the design defects in software, is equally difficult, for the same reason of complexity. Because software and any digital systems are not continuous, testing boundary values are not sufficient to guarantee correctness. All the possible values need to be tested and verified, but complete testing is infeasible. Exhaustively testing a simple program to add only two integer inputs of 32-bits (yielding 2^64 distinct test cases) would take hundreds of years, even if tests were performed at a rate of thousands per second. Obviously, for a realistic software module, the complexity can be far beyond the example mentioned here. If inputs from the real world are involved, the problem will get worse, because timing and unpredictable environmental effects and human interactions are all possible input parameters under consideration.
Software Testing is an techinque to conducted to provide with information about the quality of the product or service under test, with respect to the context in which it is intended to operate. This includes, but is not limited to, the process of executing a program or application with the intent of finding software bugs.
Here you will get to know everything you wanted to know about Software Testing. Most importantly, you will get to know this information from the practitioners, from the people working in the field, from people like you and me.
So lets start learning this art; this science or just Software Testing and start with its definition. What is Software Testing? According to the definition given by Hetzel, "Testing involves any activity aimed at evaluating an attribute or capability of a program or system and determining that it meets its required results"
In simple words, software testing is the process of finding deviation from the requirements and user expectations. As a tester, you will be the first person to look at the product from a user point of view and the last person to give objective information about its quality prior to its release. So lets talk about how you can contribute to build this knowledge base and get recognition for your spirit and hard work. Learn - On this site, you can learn about software testing, different types of testing, topics related to research, what is happening in the field, testing related news, blogs of the experts in our field, certification.
Software bugs will almost always exist in any software module with moderate size: not because programmers are careless or irresponsible, but because the complexity of software is generally intractable -- and humans have only limited ability to manage complexity. It is also true that for any complex systems, design defects can never be completely ruled out.
Discovering the design defects in software, is equally difficult, for the same reason of complexity. Because software and any digital systems are not continuous, testing boundary values are not sufficient to guarantee correctness. All the possible values need to be tested and verified, but complete testing is infeasible. Exhaustively testing a simple program to add only two integer inputs of 32-bits (yielding 2^64 distinct test cases) would take hundreds of years, even if tests were performed at a rate of thousands per second. Obviously, for a realistic software module, the complexity can be far beyond the example mentioned here. If inputs from the real world are involved, the problem will get worse, because timing and unpredictable environmental effects and human interactions are all possible input parameters under consideration.
Software Testing is an techinque to conducted to provide with information about the quality of the product or service under test, with respect to the context in which it is intended to operate. This includes, but is not limited to, the process of executing a program or application with the intent of finding software bugs.
Here you will get to know everything you wanted to know about Software Testing. Most importantly, you will get to know this information from the practitioners, from the people working in the field, from people like you and me.
So lets start learning this art; this science or just Software Testing and start with its definition. What is Software Testing? According to the definition given by Hetzel, "Testing involves any activity aimed at evaluating an attribute or capability of a program or system and determining that it meets its required results"
In simple words, software testing is the process of finding deviation from the requirements and user expectations. As a tester, you will be the first person to look at the product from a user point of view and the last person to give objective information about its quality prior to its release. So lets talk about how you can contribute to build this knowledge base and get recognition for your spirit and hard work. Learn - On this site, you can learn about software testing, different types of testing, topics related to research, what is happening in the field, testing related news, blogs of the experts in our field, certification.
