CTAL-TTA Certified Tester Advanced Level Technical Test Analyst Questions and Answers

Maintainability metrics typically used with static analysis include measures that reflect the complexity and understandability of the code, such as Number of Lines of Code (LOC), Number of Function Calls, and Comment Frequency. These metrics help in assessing how easily the software can be understood, modified, and maintained. Mean Time Between Failures (MTBF), on the other hand, is a reliability metric. It measures the time elapsed between inherent failures of a system during operation. MTBF is used to predict the system's reliability and is not directly related to the maintainability of the code. Reliability metrics like MTBF would be used in the testing phase to measure the operational reliability of the system rather than during static analysis for maintainability assessment.

In the context of software testing, different safety integrity levels (SIL) require different levels of rigor in testing. According to the IEC61508 standard, for software components rated at SIL 2, achieving 100% statement coverage and 100% decision coverage is recommended. Statementcoverage ensures that every line of code is executed at least once during testing, while decision coverage ensures that every decision in the code (e.g., every branch of an IF statement) is executed on both the true and false sides. These coverage criteria ensure a thorough testing of the software components to validate that they behave correctly in all circumstances. Multiple condition coverage and MC/DC coverage (Options A and B) are more rigorous and typically required for higher SIL levels, such as SIL 4.

The key context here is the challenge of managing limited resources, particularly ROM and RAM, due to severe restrictions on code size in consumer electronics. Lazy instantiation is a design pattern that defers the creation of an object until the first time it is needed. This approach can significantly reduce the application's memory footprint by avoiding unnecessary pre-allocation of memory, which is particularly valuable in systems where memory resources are constrained. In reviewing the architecture for such a system, it's crucial to ensure that objects are only created when necessary and that memory is optimally managed. Hence, the focus on lazy instantiation would be most important to ensure that the system uses resources efficiently and remains within the restricted code size.

Keyword-driven test automation is a framework where test cases are written using keywords that represent the actions or tests to be performed on the system. This is an extension of data-driven test automation, which focuses on separating test scripts from the test data, allowing the same test script to be run with various sets of data. Keyword-driven test automation further abstracts the process by allowing tests to be written in a more human-readable form that corresponds to business processes. This approach can improve maintainability and readability of test cases, making them easier to understand and modify. It’s not necessarily the case that one is more maintainable or easier to develop than the other (Options C and D); rather, they serve different purposes in test automation strategy.

Given the stakeholder information provided:

• Reliability is important because the system, while not business-critical, still needs a good MTBF to be successful in the market. This is directly mentioned in the stakeholder information.
• Portability is essential as the system is expected to run in multiple hardware environments and various network environments, with changes anticipated in the operational environments.

Security is not highlighted as a concern, and performance efficiency, while generally important, is less critical as the system is not used intensively and is not time-critical. Therefore, reliability and portability are the most relevant non-functional quality characteristics to test in this scenario.

In the context of an internet banking project where reliability and maintainability are emphasized, a key factor for maintainability is the modularity of the system. Implementing the user interface independently from other software modules (answer B) can significantly enhance maintainability. This is because it allows changes to be made to the user interface withoutimpacting the underlying business logic or data access layers, making the system more adaptable to change. This kind of separation of concerns is a recognized best practice in software design for maintainability. The other options (A, C, and D) relate more to reliability and security aspects than to maintainability.

The characteristics listed in the question point towards the need to manage synchronization between processes and make efficient use of limited hardware resources, such as microcontrollers and timeslots. Additionally, the complexity and concurrency of tasks highlight the importance of the software's performance over time. Time-behaviour testing is the most appropriate non-functional test type to perform in this scenario as it focuses on evaluating the timing aspects of the system, such as response times, processing times, and throughput rates. It ensures that the system meets its time-related requirements, which is critical for systems reliant on synchronization and limited by hardware performance constraints.

Performance testing is a key part of ensuring that a system can handle the expected load and perform well under high demand. This type of testing is designed to test the robustness, speed, scalability, and stability of the system under a given workload. It is not primarily concerned with security threats such as code insertion (Option A), nor with fault tolerance in terms of unexpected input values (Option B), nor with the speed of addressing user-reported defects (Option C), although these may be tangential benefits. Performance testing is focused on ensuring that the system meets performance criteria and can handle increasing loads without degradation of service, which is essential for providing a good user experience and for the system’s reliability.

Multiple condition testing requires each possible combination of conditions to be tested, whereas modified condition/decision testing (MC/DC) requires each condition to be shown to independently affect the outcome. In the case of the ATM withdrawal, TC 3 (Customer does not have sufficient funds and credit has not been granted) would not result in the machine paying out, which is a result of applying multiple condition testing. However, for MC/DC, this test case would not be included because it doesn't provide an independent assessment of either condition's effect on the decision since both conditions are negative and the outcome is as expected (no payout).

Common issues with traditional capture/playback test automation include difficulty in maintaining the scripts when software changes (option A), the challenge for non-technical persons to maintain recorded scripts (option B), and the issue that data and actions are often intertwined within the recorded script (option C), which can make them hard to understand and modify. However, the timing of the execution of the recorded script (option D), such as thedifficulty of running scripts outside office hours, is not typically a problem inherent to capture/playback test automation itself but rather an environmental or scheduling issue.