Organizations across the globe have realized the true potential of software testing before the software product is made public to end users. Numerous tools and frameworks have simplified the way we approach our testing requirements. That is why automation testing has gained such popularity in today’s world.
There is no denying the fact that software testing is now an integral part of any development process. It is about finding errors or issues in a software product, whether a web or mobile application. In order to test how the overall system behaves and operates under different scenarios, teams can perform various types of testing. Among them is system integration testing.
System integration testing involves assembling different system components logically and cost-effectively while thoroughly testing the execution of the system.
This system integration testing tutorial covers everything you need to know about system integration testing.
System integration testing, or SIT, is a comprehensive way to test software applications, including the complete system. The system is composed of smaller units of software and hardware. It ensures that the functional and hardware aspects of the software are in complete synchronization.
With this type of testing, the individual modules or components are first tested separately and then tested again once it is combined into a single system.
The following testing types are performed once the development requirements are finalized.
Unit testing provides you a way to test a unit – the smallest piece of code that can be a function, a method, or even a property. The modern versions of unit testing can be found in popular frameworks such as JUnit or even automated testing tools like LambdaTest.
System testing helps you to validate the complete software product. It falls under the category of black box testing, which is all about the external functionalities of the software from the user’s perspective.
The end-user or client can perform unit acceptance testing to verify the software product or system before it is moved to the production environment. UAT is completed at the final stages once the functional, integration, and system testing are completed.
Now that we have understood the basics of system integration testing, let us elaborate on some factors that highlight why system integration testing is crucial for your product’s success and quality:
The system contains numerous components that can be unit tested independently. As a result, system integration testing helps you to expose and correct errors before the system is handed over to the end users.
The problems or issues are discovered early, so a significant amount of time and effort can be saved as you do not have to fix those issues at the later development stages. The minimum viable product (MVP) is released only when the system integration testing is validated and passed.
Let us understand system integration testing using a real-world scenario. Assume that a product-based organization uses software to manage different customer details, storing customer information in dedicated databases.
This software contains different screens in the UI – Login, Registration, and Manage Customer Information with dedicated database support for all of these functionalities. This will be used by customers, and they are pleased when all three functionalities work fine.
However, in a few years, the organization discovered that the software was not providing the required end-user experience and meeting the customer requirements. Some enhancements were proposed to make the software perform better in the long run.
Hence, they develop a feedback module and a database. This system now has a feedback module and database that needs to be integrated with the existing software. The testing is done on the whole system after the integration and is called system integration testing. The complete system integration testing ensures that all the required systems work according to the defined functionality.
Now, let’s see some of the benefits of system integration testing.
Let us understand some of the disadvantages of system integration testing, which you should be aware of:
We discussed the pros and cons of system integration testing, but it all comes down to your experience and expertise in handling different testing types that apply to your product.
These are some prerequisites that can help you build a great system integration test plan.
Organizations need to build a plan or test strategy around system integration testing. That is why you will see more organizations investing a lot of time and effort in reinventing their testing strategies and how they operate.
The most common method for performing system integration testing is using the Data-Driven approach, where you are not required to rely much on the software testing tools
In this method, the data export and import occur between the system modules, and then the performance of each data field within the individual layer is monitored.
The following are the three main states of data flow:
Let us understand each of these flows in more detail so you can have more clarity.
The integration layer acts as a medium or interface between the data import and export. You must have basic knowledge of certain schema technologies for performing SIT at this layer.
Follow the steps below to validate the data exchange:
You must have a basic knowledge of SQL to perform the SIT at this layer.
Follow the below-mentioned steps to validate the data exchange:
You must follow the steps below to validate the data exchange:
Let us compare the two testing types based on different factors:
|System integration testing||System testing|
|It ensures individual modules interact when integrated into a complete system.||It checks if the entire system is working per its requirements.|
|It is conducted after unit testing and is performed when a new module is introduced or added to the system.||It is conducted at the final stages, which means after the completion of the integration testing, and just before the user acceptance testing.|
|This is categorized as low-level testing.||It is categorized as high-level testing.|
|This testing addresses the interface requirements between different system components.||This testing focuses on validating different test cases based on the system requirements.|
Typically, integration testing involves the ETVX method (Entry Criteria, Task, Validation, Exit Criteria). Let us understand the entry and exit criteria related to system integration testing.
It is essential to perform comprehensive system integration testing of apps and websites to deliver the right business value to the end users and customers.
Here are the four different techniques that you can follow for performing System Integration Testing:
Let us understand each of these approaches in more detail so that you can choose the technique that works best for you and your teams.
Under this approach, the testing starts with just the topmost module or component of an application. The functionality of the underlying modules is performed using stubs. Once each test is complete, the real module replaces the stub. The modules can be integrated either in a breadth-first or depth-first manner. Testing will continue until the application is complete.
The major challenge in this approach is the direct dependency on the availability of lower-level module functionality. There are delays once stubs replace the real modules, and also, writing stubs could be a challenging proposition when you are working in this approach.
This approach helps eliminate the limitations and challenges encountered in the top-down approach. In this method, the lowest-level modules are assembled to create clusters. These clusters serve as a sub-function of the application. Then a driver is created to manage the input and output details related to the test case.
After this, you can perform testing of the cluster. Once the cluster is tested, you can remove the driver, and the cluster is combined with the next upper level. This process continues until we have traversed the entire application structure.
There is no need for stubs in this approach. It is a more simplified approach as the processing moves upward and the need for drivers gets reduced. This approach works well for object-oriented systems, real-time systems, and systems that follow performance standards. The only limitation of this approach is the UI testing , which is done at last.
The top-down and bottom-up approaches discussed in the previous sections are used in combination here. The system is categorized into three different layers – the middle layer is the target layer, one layer is above the target, and there is another layer below the target.
Testing is performed in both directions and is grouped in the middle layer. The top and bottom layers can be tested in parallel. However, there is also a limitation where you can thoroughly test the individual subsystems before integration.
To overcome this limitation, we have modified sandwich testing so that you can test the top, middle, and bottom layers in parallel using stubs and drivers.
In this approach, integration is done to make sure that the required modules related to the application are ready. Once the integration is completed, then you can perform testing to check if the integrated systems are working or not.
It can be challenging to analyze the root cause with this approach when all the systems are closely integrated. This approach is useful when you are required to perform one round of system integration testing.
System integration testing is all about collaboration between different teams. We have dedicated QA teams performing system integration testing of apps and websites because they know the overall functionality updates and upgrade changes.
The developers can validate the code requirements to observe the exact system behavior. Once the development team gives the go-ahead, the QA team can perform the different testing levels based on the diverse testing requirements.
Testers can often collaborate closely with product owners or business analysts to help develop high-level test scenarios or review end-to-end test cases. This approach is useful as the product owners are closer to the users and thoroughly understand their approach in the long run.
It is better to consult the developers to ensure that the technically complicated workflows are thoroughly tested. Any team member can develop and execute end to end testing in the Agile and DevOps environments. Developers can perform peer reviews of the coding requirements. In continuous integration, testers can determine the test scenarios, developers perform the coding of the automated scripts and release engineers ensure that the tests are implemented into the continuous integration pipeline where all the team members review the results.
Since knowing who is responsible for system integration testing is important, it is worth considering the testing practices that change with time. Organizations rely more on quality engineering than quality assurance; the entire team plays a vital role in software quality. It becomes a collective effort so that you deliver exceptional outcomes to the customers in the long run.
Note:The system integration testing can also depend on the organization's goals and objectives.
Organizations are always looking to hire great system integration test specialists for managing complex testing requirements. The professionals can either work in a big team of testers or as individual contributors based on the project requirements. It is always great to have professionals who have previously encountered and handled testing challenges.
Some key skills required for this profile include:
Integration testing tools are used to test the interface between modules and find the bugs; these bugs may happen because of the multiple modules integration. The main objective of these tools is to make sure that the specific modules are working as per the customer’s needs.
Following are the test tools to create integration test suites.
During the integration testing, the components are combined and verified to ensure that all the integrated modules work as a potent combination. This test solution is widely used in financial industries, medical devices, and railways.
Wipro’s SITA helps you to overcome such limitations. This tool helps accelerate the generation of test data and test design. This is a cost-effective approach as you can reuse test data and test cases.
You can choose the required tooling options available in the market based on different factors that include:
So far, we have discussed different concepts that make system integration testing an essential part of any testing ecosystem. The true potential of system integration testing can only be leveraged when performed on scalable cloud testing platforms like LambdaTest, which simplify your testing requirements as you grow.
When building your iterative product requirements, it is important to validate and test them quickly before they are handed over to the customers for feedback and input. You cannot rely on traditional working methods, where it takes a lot of time to release the final product in the market. With LambdaTest's continuous quality cloud, you can test and ship your software products at a lighter pace. It offers manual and automated testing across 3000+ real browsers, devices, and operating systems combinations.
System integration is a continuous process where you tend to perform the testing whenever new systems are integrated. You can follow some best practices to ensure that your system integration testing delivers the required outcomes:
In this system integration testing guide, we discussed the different features and capabilities that system integration testing offers. Testing is an integral part of validating the performance of any website before end customers use it. That is why it is essential to thoroughly validate all the required components once they are completely integrated into a system. You can discover the actual value and performance at the component level and evaluate the performance metrics related to the entire system.
LambdaTest has transformed the way organizations reinvent and evolve their testing strategies. That is why cross browser testing is commonly adopted by different leading organizations going forward.
If you are a growing startup looking to redefine or reinvent your testing requirements related to system integration, you should try the LambdaTest platform.
In user acceptance testing (UAT), the application is tested to ensure it meets its business needs. In contrast, in system integration testing (SIT), the application is tested to verify it meets its engineering specifications.
In order for a software application to be cleared for use, it must pass four main stages of testing: unit testing, integration testing, system testing, and acceptance testing.