Which layer of the OSI model is primarily associated with MAC addresses?
- Data Link Layer
- Network Layer
- Physical Layer
- Transport Layer
MAC addresses are primarily associated with the Data Link Layer (Layer 2) of the OSI model. This layer is responsible for addressing and controlling access to the physical medium (e.g., Ethernet).
While IP addresses can be dynamically assigned by DHCP, the _______ address is hard-coded into a device's NIC.
- DNS
- Host
- MAC
- Subnet
The correct answer is "MAC" (Media Access Control) address. The MAC address is a unique hardware address assigned to a network interface controller (NIC) at the time of manufacturing. It is used for identifying devices on a physical network. Unlike IP addresses, which can change dynamically, MAC addresses are permanent and tied to the device.
How does ARP differentiate between requests and responses within the protocol?
- By checking the IP address
- By examining the hardware address
- By examining the operation code (OpCode) field
- By using a timestamp
ARP (Address Resolution Protocol) uses an OpCode field within the packet to distinguish between requests and responses. When an ARP packet has an OpCode of 1, it's a request, and when it's 2, it's a response. This allows devices to understand the purpose of the ARP packet.
An engineer is troubleshooting a communication system where data gets corrupted occasionally. He notices that only single-bit errors are occurring. Which error correction method can be efficient for such scenarios?
- CRC (Cyclic Redundancy Check)
- Hamming Code
- Parity Bit
- Reed-Solomon Code
Hamming Code is an error correction technique that is efficient for correcting single-bit errors. It adds parity bits to the data, allowing for the detection and correction of single-bit errors.
How do idempotency considerations in API design affect error handling?
- They complicate error handling by introducing unnecessary complexity
- They have no impact on error handling
- They make error handling irrelevant
- They simplify error handling by ensuring the same request can be retried without side effects
Idempotency considerations in API design are crucial for error handling. When an operation is idempotent, it means that repeating the same request will not produce different results, making error handling more predictable and manageable. By ensuring that the same request can be retried without causing unintended side effects, idempotency simplifies error handling in API design.
When conducting API tests, what is the importance of HTTP status codes?
- Indicate success or failure of a request
- None of the above
- Provide encryption for the data transfer
- Specify the programming language used
HTTP status codes convey whether a request was successful or not, helping testers understand the outcome and take appropriate actions based on the code received.
Which tool is commonly used for logging API activity in production?
- Elasticsearch
- Postman
- Swagger
- Winston
Winston is a widely used logging tool for API activity in production. It allows developers to capture and analyze logs effectively. With features like log rotation and customizable log levels, Winston provides the necessary tools to manage and troubleshoot API activities in a production environment.
How does the HTTP status code 404 differ from 500?
- 404 - Resource not found
- 404 - Server Error
- 500 - Internal Server Error
- 500 - Resource not found
The HTTP status code 404 indicates that the requested resource is not found, while 500 indicates an internal server error. These codes are crucial for understanding and troubleshooting web interactions.
In the context of negative testing, ensuring proper handling of _________ is key to maintaining API stability and performance.
- Edge Cases
- Input Validation
- Network Latency
- Timeouts
In the context of negative testing, ensuring proper handling of edge cases is vital. Edge cases represent scenarios that are at the limits or boundaries of the expected input range and can uncover vulnerabilities that might otherwise go unnoticed. Proper handling of edge cases contributes to API stability and performance.
In a case where a GraphQL API experiences performance issues, what should be the focus of your testing strategy?
- Caching Mechanism
- Network Latency
- Query Complexity
- Schema Validation
The complexity of GraphQL queries can impact API performance. Testing and optimizing the query complexity should be a focus to address performance issues.
To simulate real-world scenarios, _________ should be incorporated into the testing process of a third-party API integration.
- Load Testing
- Performance Testing
- Scalability Testing
- Stress Testing
Performance Testing is essential to simulate real-world scenarios in the testing process of a third-party API integration. It helps evaluate the system's responsiveness, reliability, and scalability under various conditions, ensuring optimal performance in different situations.
Which tool is commonly used for REST API testing and has features for designing, mocking, and debugging APIs?
- Appium
- JUnit
- Postman
- Selenium
Detailed Postman is a popular tool for REST API testing, offering functionalities like API design, mocking, and debugging. It simplifies the testing process and is widely used in the industry.