- (Topic 3)
A virtual machine has the following configuration:
· IPv4 address: 169.254.10.10
· Subnet mask: 255.255.0.0
The virtual machine can reach colocated systems but cannot reach external addresses on the internet. Which of the following is most likely the root cause?
Correct Answer:
B
The IP address 169.254.10.10 is an APIPA (Automatic Private IP Addressing) address, which is assigned by the operating system when a DHCP server is not available or reachable. APIPA addresses are in the range of 169.254.0.0/16, and they allow the device to communicate with other devices on the same local network, but not with external networks or the internet. Therefore, the most likely root cause of the virtual machine’s connectivity issue is that the DHCP server is offline or malfunctioning, and the virtual machine cannot obtain a valid IP address from it.
References
✑ 1: CompTIA Network+ N10-008 Certification Study Guide, page 86
✑ 2: CompTIA Network+ N10-008 Exam Subnetting Quiz, question 9
✑ 3: CompTIA Network+ N10-008 Certification Practice Test, question 4
- (Topic 3)
Which of the following architectures would allow the network-forwarding elements to adapt to new business requirements with the least amount of operating effort?
Correct Answer:
A
Software-defined network (SDN) is a network architecture that allows the network- forwarding elements to be controlled by a centralized software application. This enables the network to adapt to new business requirements with the least amount of operating effort, as the network administrator can configure and manage the network from a single console, without having to manually configure each device individually. SDN also provides more flexibility, agility, and scalability for the network, as it can dynamically adjust the network resources and policies based on the application needs and traffic conditions.
References:
✑ CompTIA Network+ Certification Exam Objectives, page 5, section 1.3: “Explain the concepts and characteristics of routing and switching.”
✑ Software-Defined Networking – CompTIA Network+ N10-007 – 1.3, video lecture by Professor Messer.
- (Topic 2)
A network technician has multimode fiber optic cable available in an existing IDF. Which of the following Ethernet standards should the technician use to connect the network switch to the existing fiber?
Correct Answer:
C
1000BaseSX is an Ethernet standard that should be used to connect the network switch to the existing multimode fiber optic cable. 1000BaseSX is a Gigabit Ethernet standard that uses short-wavelength laser (850 nm) over multimode fiber optic cable. It can support distances up to 550 meters depending on the cable type and quality. It is suitable for short-range network segments such as campus or building backbone networks. References: https://www.cisco.com/c/en/us/products/collateral/interfaces- modules/gigabit-ethernet-gbic-sfp-modules/product_data_sheet09186a008014cb5e.html
- (Topic 3)
An auditor assessing network best practices was able to connect a rogue switch into a network Jack and get network connectivity. Which of the following controls would BEST address this risk?
Correct Answer:
A
- (Topic 3)
A firewall administrator observes log entries of traffic being allowed to a web server on port 80 and port 443. The policy for this server is to only allow traffic on port 443. The firewall administrator needs to investigate how this change occurred to prevent a reoccurrence. Which of the following should the firewall administrator do next?
Correct Answer:
A
Firewall audit logs are records of the changes made to the firewall configuration, policies, and rules. They can help the firewall administrator to track who, when, and what changes were made to the firewall, and identify any unauthorized or erroneous modifications that could cause security issues or network outages. By consulting the firewall audit logs, the firewall administrator can investigate how the change that allowed traffic on port 80 to the web server occurred, and prevent it from happening again