CompTIA N10-008 Practice Test - Questions Answers, Page 54

The data link layer is responsible for defining the format of data on the network and providing physical transmission of data. Devices that operate at this layer include switches and network interface cards (NICs). Encapsulations that are used at this layer include frames, which are units of data that contain a header, payload, and trailer. Frames are used to identify the source and destination of data on the network and to perform error detection. Reference: CompTIA Network+ N10-008 Certification Study Guide, page 9; The Official CompTIA Network+ Student Guide (Exam N10-008), page 1-6.

Switches are devices that forward data based on MAC addresses. They create separate collision domains for each port, which reduces the chance of collisions on the network. However, if multiple switches are connected together without proper configuration, they can create broadcast storms, which are situations where broadcast frames are endlessly forwarded between switches, consuming network bandwidth and resources. Broadcast storms can be prevented by using protocols such as Spanning Tree Protocol (STP), which eliminates loops in the network topology. Reference: CompTIA Network+ N10-008 Certification Study Guide, page 67; The Official CompTIA Network+ Student Guide (Exam N10-008), page 2-14.

Multipathing is a technique that allows a device to use more than one path to communicate with another device. This provides redundancy, load balancing, and fault tolerance for network connections. A business that purchased redundant internet connectivity from two separate ISPs is most likely implementing multipathing to ensure continuous access to the internet in case one ISP fails or becomes congested. Reference: CompTIA Network+ N10-008 Certification Study Guide, page 437; The Official CompTIA Network+ Student Guide (Exam N10-008), page 16-8.

The subnet mask is a binary value that defines how many bits of an IP address are used to identify the network and how many bits are used to identify the host. The subnet mask also determines the size and number of subnets in a network. The ipconfig command shows the current IP configuration of a device, including the subnet mask. In this case, the subnet mask is misconfigured because it does not match the network address of the device. The device has an IP address of 192.168.1.55, which belongs to the network 192.168.1.0/24 (with a subnet mask of 255.255.255.0). However, the subnet mask is set to 225.225.225.224, which is an invalid value that does not correspond to any network prefix length. This causes the device to be unable to communicate with other devices on the same network or access the default gateway. Reference: CompTIA Network+ N10-008 Certification Study Guide, page 109; The Official CompTIA Network+ Student Guide (Exam N10-008), page 5-4.

Anycast addressing is a network addressing and routing methodology in which a single destination address has multiple routing paths to two or more endpoint destinations. Routers will select the desired path on the basis of number of hops, distance, lowest cost, latency measurements or based on the least congested route. Anycast addressing is designed to provide high availability and low latency for services that have multiple instances across the world, such as DNS servers. By using anycast addressing, the customer can ensure that servers are accessed based on whichever one is topographically closest to the destination. If the server does not respond, then the next topographically closest server should respond. Reference: [CompTIA Network+ Certification Exam Objectives], [Anycast - Wikipedia]

The agent was trying to duplicate the problem by asking the user to perform the same steps that led to the issue. This is a common troubleshooting technique that helps the agent to identify the root cause of the problem and verify if it is reproducible or intermittent. By duplicating the problem, the agent can also gather more information about the symptoms and error messages that the user encountered. Reference: [CompTIA Network+ Certification Exam Objectives], [Troubleshooting Methodology - CompTIA Network+ N10-007 - 1.4 | Professor Messer IT Certification Training Courses]

Single-mode fiber is a type of optical fiber that has a small core diameter and allows only one mode of light to propagate. This reduces signal attenuation and increases transmission distance, making it suitable for long-distance communication networks. Single-mode fiber can carry data over thousands of kilometers without requiring repeaters or amplifiers. Single-mode fiber is also immune to electromagnetic interference and has a higher bandwidth than multimode fiber. Therefore, single-mode fiber is the best cable type for connecting sites on multiple continents. Reference: [CompTIA Network+ Certification Exam Objectives], [Single-mode optical fiber - Wikipedia]

Single-mode fiber optic cable uses a single ray of light to transmit data. This allows it to achieve very low attenuation and high bandwidth.

Multimode fiber optic cable uses multiple rays of light to transmit data. This results in higher attenuation and lower bandwidth than single-mode cable.

Twisted pair copper cable uses two insulated copper wires to transmit data. It is less expensive than fiber optic cable, but it has higher attenuation and lower bandwidth.

When choosing a cable type for a long-distance application, it is important to consider the following factors:

Attenuation: The amount of signal loss that occurs over the length of the cable.

Bandwidth: The amount of data that can be transmitted over the cable per second.

Cost: The cost of the cable and installation.

Single-mode fiber optic cable is the best choice for long-distance applications because it has the lowest attenuation and highest bandwidth of any cable type. However, it is also the most expensive cable type.

A link-state algorithm is a routing algorithm that uses information about the state of each link in the network to calculate the shortest path from one node to every other node. A link-state algorithm requires each router to maintain a complete map of the network topology and exchange link-state advertisements with its neighbors periodically or when a change occurs. A link-state algorithm uses a mathematical formula called Dijkstra's algorithm to find the shortest path based on the link costs. A link-state algorithm provides the fastest convergence time because it can quickly detect and adapt to network changes. Reference: [CompTIA Network+ Certification Exam Objectives], [Link-state routing protocol - Wikipedia]

The reason the network is not functional is that STP (Spanning Tree Protocol) is not configured on the switches. STP is a protocol that prevents loops in a network topology by blocking redundant links between switches. If STP is not enabled, the switches will forward broadcast frames endlessly, creating a broadcast storm that consumes network resources and disrupts communication. Reference: CompTIA Network+ N10-008 Certification Study Guide, page 67; The Official CompTIA Network+ Student Guide (Exam N10-008), page 2-14.