System Integration (Software) Testing (SIT)

System Integration Testing (SIT) is the type of software testing that is carried out to perform the overall testing of a complete system that consists of many integrated components. The system on which SIT is performed may have different hardware parts, different software parts or both hardware and software. SIT is the process of fabricating the constituent integral parts of a system in a reasonable and logical way. SIT performs the testing in a less cost. It checks the full functionality of the system. System test is involved in SIT which is a process of verification of the system fulfilling the requirements and it test whether the system performs in according to the user's requirements. During the development phase, system integration testing is the first testing process performed after the system is assembled. SIT can also be defined as a testing process that exercises the coexistence of a software system with other system. Multiple integrated systems are involved in it and it is assumed that each have already passed system integration testing. SIT is performed to test the interactions among several integrated components.

SIT is a black-box testing technique.

Objective of System Integration Testing: The objective of SIT is to:

• To meet software with user requirements.
• To maximize the memory usage.
• To control data flow in within the system.
• To test the control flow of the system.
• To find the errors and bugs in the system.
• To minimize time consumption for testing process.

Major States of SIT: There are three major states of system integration testing:

1. Data state within the integration layer: Integration layer is the medium used for data transformation. Different web services are involved in this layer which is used as medium for data sending and receiving. There are several check-points where the validation of data is checked and there are several protocols used in it. Middleware is also used as medium for transformation which allows the data mapping against the cross-checking.
2. Data state within the database layer: Database layer consists of several steps involved in it. It checks whether the data is transformed from integration layer to database layer. Data properties are checked and data validation process is performed. Mainly SQL is used for data storing and data manipulation process.
3. Data state within the application layer: Application layer is used to create a data map for databases and check its interaction with user interface. Data properties are also checked in it.

System Integration Testing (SIT) is a type of testing that focuses on verifying the interactions and interfaces between different systems or components of a software application. The purpose of SIT is to ensure that the different components are integrated and work together correctly as a system.

SIT is typically performed after unit testing and integration testing, and before user acceptance testing (UAT). SIT tests the end-to-end flow of data and transactions through the system, including the interfaces between the components, the communication protocols, the data transfer mechanisms, and the shared resources.

During SIT, various test scenarios are executed to ensure that the components of the system interact with each other seamlessly and correctly, and that they conform to the functional and non-functional requirements of the system. The testing team may use automated testing tools and techniques to simulate various real-world scenarios and edge cases.

The test environment for SIT should closely resemble the production environment, including all the hardware, software, and networking components, to ensure that the system behaves as expected in the production environment. Any defects or issues that are discovered during SIT are logged and tracked, and are usually fixed before the system is deployed for user acceptance testing or production.

In summary, SIT is an important testing phase in the software development lifecycle that ensures that the different components of a system are integrated and work together correctly. SIT helps to identify and resolve any issues or defects before the system is deployed for user acceptance testing or production, thereby reducing the risk of costly and time-consuming rework.

There are several advantages of System Integration Testing (SIT) in software development. Here are some of them:

1. Ensures system functionality: SIT verifies that the different components of the system are integrated and work together correctly, ensuring that the overall system meets the functional and non-functional requirements.
2. Reduces risk: SIT helps to identify and resolve any issues or defects before the system is deployed for user acceptance testing or production, reducing the risk of costly and time-consuming rework.
3. Improves system quality: By verifying the interactions and interfaces between different systems or components, SIT helps to improve the quality of the system and ensures that it performs as expected.
4. Enhances system performance: SIT helps to identify and address any performance issues that may arise due to the interactions and interfaces between different components of the system.
5. Increases team collaboration: SIT requires close collaboration between the different teams responsible for developing and testing the system, enhancing team collaboration and communication.
6. Supports agile development: SIT is an essential testing phase in agile development methodologies, helping to ensure that the system is tested comprehensively and meets the specified requirements.

In summary, SIT plays a critical role in ensuring that the different components of a software application are integrated and work together correctly. SIT helps to identify and resolve any issues or defects, thereby reducing risk and improving system quality and performance.