- (Topic 3)
A network administrator is investigating a network event that is causing all communication to stop. The network administrator is unable to use SSH to connect to the switch but is able to gain access using the serial console port. While monitoring port statistics, the
administrator sees the following:

Which of the following is MOST likely causing the network outage?

1. A. Duplicate IP address
2. B. High collisions
3. C. Asynchronous route
4. D. Switch loop

Correct Answer: B

- (Topic 3)
A network technician is troubleshooting a connectivity issue. All users within the network report that they are unable to navigate to websites on the internet; however, they can still access local network resources. The technician issues a command and receives the following results:

Which of the following best explains the result of this command?

1. A. Incorrect VLAN settings
2. B. Upstream routing loop
3. C. Network collisions
4. D. DNS misconfiguration

Correct Answer: D
The users are unable to navigate to websites on the internet but can access local network resources, indicating a possible DNS issue. The ping command result showing “TTL expired in transit” suggests that packets are not reaching their destination due to a DNS misconfiguration that is not resolving website names into IP addresses correctly3. A possible solution is to check and correct the DNS server settings on the network devices4.
References: 3: What does “TTL expired in transit” mean?54: CompTIA Network+ N10-008 Cert Guide - Chapter 14: Network Monitoring2

- (Topic 3)
A small office has a wireless network with several access points that are used by mobile devices. Users occasionally report that the wireless connection drops or becomes very slow. Reports confirm that this only happens when the devices are connected to the office wireless network. Which of the following is MOST likely the cause?

1. A. The configuration of the encryption protocol
2. B. Interference from other devices
3. C. Insufficient bandwidth capacity
4. D. Duplicate SSIDs

Correct Answer: B
Interference from other devices can cause wireless connection drops or slow performance. This can happen when devices use the same or overlapping frequency channels as the wireless network, such as cordless phones, microwaves, Bluetooth devices, etc. To avoid interference, it is recommended to use non-overlapping channels and avoid placing wireless access points near potential sources of interference. References: Network+ Study Guide Objective 2.1: Explain the purposes and use cases for advanced network devices. Subobjective: Wireless controllers.

- (Topic 3)
Which of the following is the MOST effective security control to keep a company's physical perimeter protected against intrusions leveraged by social-engineering techniques?

1. A. Employee training
2. B. Biometric lockers
3. C. Access control vestibule
4. D. Motion detection

Correct Answer: A
The most effective security control to keep a company’s physical perimeter protected against intrusions leveraged by social-engineering techniques is employee training. Employee training is a process of educating and raising awareness among staff members about security policies, procedures, and best practices. Employee training can help prevent social-engineering attacks, which are attempts to manipulate or deceive people into revealing sensitive information or granting unauthorized access to resources. Social-engineering techniques can include phishing, impersonation, tailgating, dumpster diving, or baiting. References: CompTIA Network+ N10-008 Certification Study Guide, page 343; The Official CompTIA Network+ Student Guide (Exam N10-008), page 13-8.

- (Topic 3)
In which of the following components do routing protocols belong in a software-defined network?

1. A. Infrastructure layer
2. B. Control layer
3. C. Application layer
4. D. Management plane

Correct Answer: B
A software-defined network (SDN) is a network architecture that decouples the control plane from the data plane and centralizes the network intelligence in a software controller. The control plane is the part of the network that makes decisions about how to route traffic, while the data plane is the part of the network that forwards traffic based on the control plane’s instructions. The control layer is the layer in an SDN that contains the controller and the routing protocols that communicate with the network devices. The control layer is responsible for managing and configuring the network devices and providing them with the necessary information to forward traffic. References: https://www.comptia.org/training/books/network-n10-008-study-guide (page 378)