N10-008 Exam Dumps - CompTIA Network+ Certification Exam

The issue is that the host is configured with incorrect DNS settings. DNS (Domain Name System) is a service that resolves domain names to IP addresses. For example, the domain name www.comptia.org is resolved to the IP address 104.18.25.140 by a DNS server. If the host has incorrect DNS settings, such as an invalid or unreachable DNS server address, it will not be able to resolve domain names to IP addresses, and therefore it will not be able to access websites by their names. The output in the image shows that the host can ping the IP address of www.comptia.org, but it cannot ping the domain name itself, indicating a DNS problem.  References: CompTIA Network+ N10-008 Certification Study Guide, page 154; The Official CompTIA Network+ Student Guide (Exam N10-008), page 6-8.

A physical diagram is a type of diagram that shows the physical layout and connections of the network devices and components, such as routers, switches, cables, and connectors. A physical diagram may include specifications about the fiber connector types, such as LC, SC, FC, ST, MPO, etc., that are used to link the fiber optic cables and devices. A physical diagram can help to visualize the network topology, troubleshoot network problems, and plan network changes

• Attenuation is the loss of signal strength as it travels over a distance or through a medium. It is measured in decibels (dB) and can affect the quality and reliability of network communication.
• In this scenario, the connection from PC A to switch 1 is using a Cat 5 cable with a length of 394ft (120m), which exceeds the recommended maximum length of 328ft (100m) for twisted-pair cables. This can cause significant attenuation and performance degradation between PC A and PC B.
• To solve this problem, the network technician should either reduce the cable length, use a higher category cable, or insert a repeater or amplifier device to boost the signal strength.
• Interference is the unwanted noise or signal that affects the network communication. It can be caused by electromagnetic sources, such as power lines, motors, or wireless devices, or by crosstalk, which is the interference between adjacent wires in a cable. Interference can also affect the network performance, but it is not the most likely cause in this scenario, as it would affect all the connections, not just the one with the excessive cable length.
• Decibel loss is another term for attenuation, so it is not a separate option. Incorrect pinout is the wrong arrangement of wires in a cable connector, which can prevent the network devices from communicating properly. However, this is not the most likely cause in this scenario, as the cable configuration is correct (straight through) for the connection from PC A to switch 1. References:
• [CompTIA Network+ N10-008 Study Guide], Chapter 3: Network Cabling and Topologies, Section 3.1: Compare and Contrast Cabling Types, Standards, and Properties, p. 115-116
• [Professor Messer’s CompTIA N10-008 Network+ Course Notes], Section 2.1: Copper Cabling, p. 19
• Network+ N10-008 Practice Test | CertBlaster, Question 1

The best choice for configuring link port aggregation between a Gigabit Ethernet distribution switch and a Fast Ethernet access switch is to use full duplex and 1GB speed for all interfaces that are participating in the link aggregation. This will allow for maximum throughput, as the full duplex connection will enable simultaneous sending and receiving of data, and the 1GB speed will ensure that the data is transferred quickly.

According to the CompTIA Network+ Study Guide, “Full-duplex Ethernet allows the network adapter to transmit and receive data simultaneously, which can result in double the bandwidth of half-duplex Ethernet.” Additionally, the official text states, “Ethernet and Fast Ethernet use different speeds for data transmission, with Ethernet being 1,000 megabits (1 gigabit) per second and Fast Ethernet being 100 megabits per second.”

The most likely cause of the administrator’s inability to connect to the internet is the incorrect default gateway. The default gateway is the IP address of the router that connects the local network to the internet. The default gateway should be in the same subnet as the IP address of the device. However, in this case, the IP address of the device is 4.11.17.6 and the subnet mask is 255.255.255.252, which means the subnet has only four addresses: 4.11.17.4, 4.11.17.5, 4.11.17.6, and 4.11.17.7. The first and the last addresses are reserved for the network and the broadcast, respectively, so the only valid addresses for the device and the gateway are 4.11.17.5 and 4.11.17.6. Therefore, the default gateway should be 4.11.17.5, not 4.11.17.1, which is in a different subnet. The routing table, the subnet mask, and the DNS are not the causes of the problem, as they are either correct or irrelevant for the internet connectivity.

References

• 1: CompTIA Network+ N10-008 Certification Study Guide, page 83-84
• 2: CompTIA Network+ N10-008 Exam Subnetting Quiz, question 8
• 3: CompTIA Network+ N10-008 Certification Practice Test, question 3

a network tap is a way of connecting an IDS out of band, which means it does not interfere with the normal network traffic. A network tap allows you to view a copy of the network traffic transmitted over the media being tapped.

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. References: [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.

According to the CompTIA troubleshooting methodology1, testing the theory is the step where the network administrator verifies if the problem is caused by a specific factor or change. This step involves checking the system logs, running diagnostic tools, or performing other tests to confirm or eliminate the possible cause.

References:

• Troubleshooting Methodology | IT Support and Help Desk | CompTIA1

Baseline configurations are the standard settings and parameters that are applied to network devices, such as switches, routers, firewalls, etc., to ensure consistent performance, security, and functionality across the network. Baseline configurations can include aspects such as IP addresses, VLANs, passwords, protocols, access lists, firmware versions, etc. Baseline configurations are usually documented and updated regularly to reflect any changes or modifications made to the network devices.

The lead network engineer most likely provided baseline configurations to the network administrator to ensure that the new switches are set up properly and in accordance with the network design and policies. Baseline configurations can help to simplify the deployment process, reduce errors and inconsistencies, and facilitate troubleshooting and maintenance.

The other options are not correct because they are not the most likely documentation that the lead network engineer provided to the network administrator. They are:

• Physical network diagram. A physical network diagram is a graphical representation of the physical layout and connections of the network devices and components, such as cables, ports, switches, routers, servers, etc. A physical network diagram can help to visualize the network topology, identify the locations and distances of the devices, and plan for cabling and power requirements. However, a physical network diagram does not provide the specific settings and parameters that need to be configured on the network devices, such as the switches.
• Site survey reports. A site survey report is a document that summarizes the findings and recommendations of a site survey, which is a process of assessing the suitability and readiness of a location for installing and operating network devices and components. A site survey report can include aspects such as environmental conditions, power and cooling availability, security and safety measures, interference and noise sources, signal coverage and quality, etc. A site survey report can help to identify and resolve any potential issues or challenges that may affect the network performance and reliability. However, a site survey report does not provide the specific settings and parameters that need to be configured on the network devices, such as the switches.
• Logical network diagram. A logical network diagram is a graphical representation of the logical structure and functionality of the network devices and components, such as subnets, IP addresses, VLANs, protocols, routing, firewall rules, etc. A logical network diagram can help to understand the network design, architecture, and policies, as well as the data flow and communication paths between the devices. However, a logical network diagram does not provide the specific settings and parameters that need to be configured on the network devices, such as the switches.

References1: Network+ (Plus) Certification | CompTIA IT Certifications2: What is a Baseline Configuration? - Definition from Techopedia3: What is a Physical Network Diagram? - Definition from Techopedia4: What is a Site Survey? - Definition from Techopedia5: [What is a Logical Network Diagram? - Definition from Techopedia]

The best metric for a network administrator to check is hop-by-hop network latency. This is because network latency is the time it takes for a packet to travel from the source to the destination, and it affects the loading speed of web pages. Hop-by-hop network latency measures the latency between each pair of routers or switches along the network path, and it can help identify where the delay is occurring. By checking the hop-by-hop network latency, the network administrator can determine if the problem is caused by a slow or congested link, a misconfigured or faulty device, or a routing issue.

Jitter is the variation in latency over time, and it affects the quality of voice and video applications. Jitter does not directly affect the loading speed of web pages, and it is not a useful metric for troubleshooting this issue.

Server interface CRC errors are errors that occur when the cyclic redundancy check (CRC) of a packet does not match the expected value, indicating data corruption. Server interface CRC errors can affect the reliability and integrity of data transmission, and they can be caused by faulty cables, connectors, or interfaces. Server interface CRC errors do not necessarily affect the loading speed of web pages, unless they are severe enough to cause retransmissions or packet loss.

Server NetFlow data is data that is collected and analyzed by the NetFlow protocol, which monitors and reports on network traffic flows. Server NetFlow data can provide information on the volume, type, and direction of traffic that is sent or received by the server, as well as the source and destination IP addresses, ports, and protocols. Server NetFlow data can help identify network usage patterns, trends, and anomalies, but it does not measure the latency or performance of the network.

ReferencesWhat is Network Latency and How to Measure ItHow to Troubleshoot Network Latency IssuesWhat is Jitter and How to Measure ItWhat is CRC Error and How to Fix ItWhat is NetFlow and How Does It WorkCompTIA Network+ Certification All-in-One Exam Guide, Eighth Edition (Exam N10-008)

- the microwave was already removed from the office

- the signal is OK now

- Notice that the question mentions "numerous cubicles and wooden walls" - meaning the signal now won't have the interference as before

- KEY POINT: the admin wants to "maximize the range of the signal:"

Manually change the frequency to 2.4 GHz for more reliable speeds and range. While 5 GHz gives you a stronger signal, it doesn't travel through walls or ceilings as well, so it doesn't give you the best range.

"Microwave ovens: Older microwave ovens, which might not have sufficient shielding, can emit relatively high-powered signals in the 2.4GHz band, resulting in significant interference with WLAN devices operating in the 2.4GHz band."

A 110 block is a type of punch-down block that is used to distribute Ethernet to multiple computers in an office. A punch-down block is a device that connects one group of wires to another group of wires by using a special tool that pushes the wires into slots on the block. A 110 block is a non-proprietary standard that supports up to Category 6 cabling and can be used for voice or data applications. References: https://www.comptia.org/training/books/network-n10-008-study-guide (page 64)

A vulnerability is a security flaw in an application or network that can be exploited by an attacker, allowing them to gain access to sensitive data or take control of the system. Vulnerabilities can range from weak authentication methods to unpatched software, allowing attackers to gain access to the system or data they would not otherwise be able to access. Exploits are programs or techniques used to take advantage of vulnerabilities, while threats are potential dangers, and risks are the likelihood of a threat becoming a reality.

A protocol analyzer is the best way to verify traffic to and from the server. A protocol analyzer, also known as a packet sniffer or network analyzer, is a tool that captures and analyzes the network packets that are sent and received by a device. A protocol analyzer can show the source and destination IP addresses, ports, protocols, and payload of each packet, as well as any errors or anomalies in the network communication. A protocol analyzer can help troubleshoot network connectivity issues by identifying the root cause of the problem, such as misconfigured firewall rules, incorrect routing, or faulty network devices12.

To use a protocol analyzer to verify traffic to and from the server, the customer can follow these steps:

• Install a protocol analyzer tool on a device that is connected to the same network as the server, such as Wireshark3 or Microsoft Network Monitor4.
• Select the network interface that is used to communicate with the server, and start capturing the network traffic.
• Filter the captured traffic by using the IP address or hostname of the server, or by using a specific port or protocol that is used by the database service.
• Analyze the filtered traffic and look for any signs of successful or failed connection attempts, such as TCP SYN, ACK, or RST packets, or ICMP messages.
• If there are no connection attempts to or from the server, then there may be a problem with the network configuration or device settings that prevent the traffic from reaching the server.
• If there are connection attempts but they are rejected or dropped by the server, then there may be a problem with the server configuration or service settings that prevent the traffic from being accepted by the server.

The other options are not the best ways to verify traffic to and from the server. nmap is a tool that can scan a network and discover hosts and services, but it cannot capture and analyze the network packets in detail. ipconfig is a command that can display and configure the IP settings of a device, but it cannot monitor or test the network communication with another device. Speed test is a tool that can measure the bandwidth and latency of a network connection, but it cannot diagnose or troubleshoot specific network problems.

• Encryption is the process of transforming data into an unreadable format using a secret key or algorithm. It can protect sensitive information from unauthorized access or theft, even if the device is lost or stolen.
• Factory reset is the process of restoring a device to its original settings and deleting all user data and applications. It can be used to erase personal information from a device before selling or disposing of it, but it does not prevent data recovery by forensic tools. Therefore, option A is incorrect.
• Autolock is the feature that automatically locks a device after a period of inactivity or when the power button is pressed. It can prevent unauthorized access to a device by requiring a passcode, pattern, fingerprint, or face recognition to unlock it. However, it does not protect the data stored on the device from being extracted by other means. Therefore, option B is incorrect.
• Two-factor authentication is the method of verifying a user’s identity by requiring two pieces of evidence, such as a password and a code sent to a phone or email. It can enhance the security of online accounts and services, but it does not apply to the data stored on a device. Therefore, option D is incorrect.

References:

• CompTIA Network+ N10-008 Study Guide, Chapter 9: Network Security, pages 403-404, 407-408, 411-412.
• Professor Messer’s Network+ Video Course, Section 5.1: Network Security Devices and Technologies, videos 5.1.1 - 5.1.3, 5.1.6, 5.1.7.
• CompTIA Network+ (N10-008) Sample Questions, Question 15.

• A disaster recovery plan is a document that outlines the procedures and steps to restore the normal operations of a network in the event of a disaster, such as a fire, flood, power outage, cyberattack, or human error. It includes the roles and responsibilities of the staff, the backup and recovery strategies, the communication channels, the testing and maintenance schedules, and the inventory of the network assets and resources. A disaster recovery plan needs to be updated to reflect any changes in the network topology, configuration, or equipment, such as the installation of an additional IDF (Intermediate Distribution Frame), which is a wiring closet that connects the MDF (Main Distribution Frame) to the end devices. Updating the disaster recovery plan ensures that the network administrator has the most accurate and current information to restore the network in case of a disaster.
• A physical network diagram is a visual representation of the physical layout and connections of the network devices, such as routers, switches, firewalls, servers, workstations, printers, and cables. It shows the location, name, IP address, MAC address, and port number of each device, as well as the type, length, and color of each cable. A physical network diagram needs to be updated to reflect any changes in the network infrastructure, such as the installation of an additional IDF, which adds more devices and cables to the network. Updating the physical network diagram helps the network administrator to troubleshoot, monitor, and document the network performance and status.
• A data loss prevention policy is a document that defines the rules and guidelines to prevent the unauthorized access, disclosure, modification, or deletion of sensitive or confidential data on the network. It includes the classification of the data, the encryption and backup methods, the access control and authentication mechanisms, the audit and logging procedures, and the incident response and reporting protocols. A data loss prevention policy does not need to be updated to reflect the installation of an additional IDF, unless the IDF contains devices or cables that handle sensitive or confidential data, in which case the policy should specify the security measures and controls for those devices or cables.
• A BYOD (Bring Your Own Device) policy is a document that regulates the use of personal devices, such as smartphones, tablets, laptops, or USB drives, on the network. It includes the requirements and restrictions for the devices, the network access and security policies, the user rights and responsibilities, the support and maintenance services, and the legal and ethical implications. A BYOD policy does not need to be updated to reflect the installation of an additional IDF, unless the IDF affects the network access or security of the personal devices, in which case the policy should clarify the impact and the actions for the users.
• An acceptable use policy is a document that specifies the rules and expectations for the appropriate and ethical use of the network resources and services by the users. It includes the purpose and scope of the network, the acceptable and unacceptable behaviors and activities, the consequences and penalties for violations, and the user acknowledgment and agreement. An acceptable use policy does not need to be updated to reflect the installation of an additional IDF, unless the IDF changes the purpose or scope of the network, in which case the policy should inform the users of the changes and the implications.
• A non-disclosure agreement is a legal contract that binds the parties involved in the network project or service to keep the confidential information secret and not to share it with any unauthorized third parties. It includes the definition and scope of the confidential information, the duration and termination of the agreement, the exceptions and exclusions, the remedies and damages, and the signatures and dates of the parties. A non-disclosure agreement does not need to be updated to reflect the installation of an additional IDF, unless the IDF involves confidential information that is not covered by the existing agreement, in which case the agreement should be amended or renewed to include the new information. References:
• CompTIA Network+ N10-008 Study Guide, Chapter 3: Network Operations, Section 3.1: Explain the importance of documentation and diagrams, Page 131-136
• Professor Messer’s Network+ N10-008 Course Notes, Page 20
• Professor Messer’s Network+ N10-008 Video Training Course, Section 3.1: Network Documentation, Video 3.1.1: Network Documentation Types

Traffic shaping is a bandwidth management technique that uses buffers at the client side to prevent TCP retransmissions from occurring when the ISP starts to drop packets of specific types that exceed the agreed traffic rate. Traffic shaping delays or queues packets that exceed the traffic rate, instead of dropping them, and sends them later when the traffic rate is lower. This reduces the number of TCP retransmissions and improves the overall network performance. Traffic shaping can also prioritize packets based on their type, source, destination, or other criteria. References: Routing Technologies and Bandwidth Management | Foundation Topics | Pearson IT Certification, CompTIA Network+ Certification Exam Objectives

Assigning a new IP address range to the local company is the best option to quickly connect the two companies without causing any IP address conflicts or overlaps. This option requires reconfiguring the local company’s network devices and updating the routing tables on both sides, but it avoids the need for any NAT or static routing solutions that may introduce additional complexity, cost, or performance issues12

References1: Connecting Networks with Overlapping IP Ranges 2: What Is Network Address Translation (NAT)?

Techniques to check if a connection was made by a human user, such as CAPTCHAs, are effective against automated attacks like:

• A. Brute-force: This attack method involves trying many passwords or passphrases with the hope of eventually guessing correctly.
• B. Dictionary: Similar to brute-force, this attack uses a list of words to attempt to guess passwords or encryption keys.

These techniques are not designed to protect against:

• C. On-path attack: Previously known as a man-in-the-middle attack, where the attacker intercepts communication between two parties.
• D. Phishing: A social engineering attack aiming to trick users into giving up sensitive information.
• E. Shoulder surfing: Direct observation techniques, such as looking over someone’s shoulder to get information.
• F. Evil twin: A rogue Wi-Fi access point that appears legitimate but is set up to eavesdrop on wireless communications.

TXT stands for Text and is a type of DNS record that can store arbitrary text data associated with a domain name. TXT records can be used for various purposes, such as verifying the ownership of a domain, providing information about a domain, or implementing security mechanisms such as SPF (Sender Policy Framework) or DKIM (DomainKeys Identified Mail). In this scenario, the security company most likely asked the company to configure a TXT record with a specific value that can prove the ownership of the domain. AAAA stands for IPv6 Address and is a type of DNS record that maps a domain name to an IPv6 address. CNAME stands for Canonical Name and is a type of DNS record that maps an alias name to another name. SRV stands for Service and is a type of DNS record that specifies the location of a service on a network.

References: CompTIA Network+ Certification Exam Objectives Version 7.0 (N10-007), Objective 1.8: Explain the purposes and use cases for advanced networking devices.

• The question asks about the best method to use for the network team to receive UPS status notifications after a critical power issue. The UPS is an uninterruptible power supply that provides backup power to the network devices in case of a power outage or surge1.
• The answer is traps, which are unsolicited messages that are sent from an agent to a manager to notify about an event or a condition that requires attention2. Traps can be used to alert the network team about the UPS status changes, such as battery level, load, temperature, or power failure3.
• MB, NetFlow, and Syslog are not the correct answers, because they are not the best methods to use for the UPS status notifications. MB stands for megabyte, which is a unit of data storage4. NetFlow is a protocol that collects and analyzes network traffic data. Syslog is a standard for logging and monitoring system events. These methods are not designed to send alerts about the UPS status changes, and they may not be reliable or timely in case of a critical power issue. References:
• Uninterruptible Power Supply
• Traps
• UPS Monitoring and Management
• Megabyte
• [NetFlow]
• [Syslog]
• CompTIA Network+ N10-008 Study Guide

To allow each device to access its expected network without additional connections, the administrator needs to configure VLANs (virtual LANs) on the switch. VLANs are logical groups of devices that share the same broadcast domain, regardless of their physical location or connection. VLANs can improve network performance, security, and management by isolating traffic and reducing broadcast storms. To configure VLANs on the switch, the administrator needs to assign each device port to a specific VLAN and set the VLAN tagging mode. VLAN tagging is a method of adding a VLAN identifier to the Ethernet frames to indicate which VLAN they belong to. There are two types of VLAN tagging: untagged and tagged. Untagged VLAN tagging means that the switch removes the VLAN identifier from the frames before sending them to the device port. This is suitable for end devices that do not support VLAN tagging, such as PCs, printers, etc. Tagged VLAN tagging means that the switch keeps the VLAN identifier on the frames when sending them to the device port. This is suitable for devices that support VLAN tagging, such as routers, servers, other switches, etc. To allow each device to access the rest of the network, the administrator needs to configure a trunk port on the switch that connects to the uplink. A trunk port is a port that can carry traffic from multiple VLANs using tagged VLAN tagging. This way, the switch can send and receive frames from different VLANs to and from the rest of the network. Therefore, the administrator should do the following to meet the requirements:

• Untag an individual VLAN per device port. This will assign each device port to a specific VLAN and remove the VLAN identifier from the frames before sending them to the device port. This will allow each device to access its expected network without additional connections.
• Tag the three VLANs across the uplink. This will configure a trunk port on the switch that connects to the uplink and add the VLAN identifier to the frames before sending them to the uplink. This will allow the switch to carry traffic from multiple VLANs to and from the rest of the network.

References:

• VLANs and Trunks
• VLAN Tagging Explained with DTP Protocol
• Network + N10-008 practice exam
• [CompTIA N10-008 Free Certification Exam Material]
• [Free Practice Questions for CompTIA Network+Exam (N10-008)]

The application layer of the OSI model (Open Systems Interconnection) is responsible for providing services to applications that allow users to access and download files from a remote computer. These services include file transfer, email, and web access, as well as other related services. In order for a user to access and download files from a remote computer, the application layer must provide the necessary services that allow the user to interact with the remote computer.

To confirm the issue of slow network performance when accessing on-premises email, a network technician should compare the network baselines to the current network status. Here’s why:

• Reviewing logging levels of network devices (Option A) may provide information about device behavior but won’t directly confirm the email performance issue.
• Checking audit logs (Option B) is useful for security purposes but doesn’t specifically address network performance.
• Verifying LDAP accounts (Option D) is relevant for authentication but doesn’t directly relate to network performance.

Therefore, the correct answer is C. Compare the network baselines to the current network status

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)

Multicast is the network communication method to use when audio transmissions need to reach several specific devices simultaneously over an IP network. It allows for efficient network use by directing a single stream of data to multiple recipients without needing to send separate streams to each recipient. Unicast sends data to a single destination, anycast sends data to the nearest or best destination in a group, and broadcast sends data to all devices in the network segment. Thus, multicast is most appropriate for the requirement described​​.

Creating a plan of action is the step of the troubleshooting methodology that would most likely include checking through each level of the OSI model after the problem has been identified. According to the web search results, the troubleshooting methodology consists of the following steps: 12

• Define the problem: Identify the symptoms and scope of the problem, and gather relevant information from users, devices, and logs.
• Establish a theory: Based on the information collected, hypothesize one or more possible causes of the problem, and rank them in order of probability.
• Test the theory: Test the most probable cause first, and if it is not confirmed, eliminate it and test the next one. Repeat this process until the root cause is found or a new theory is needed.
• Create a plan of action: Based on the confirmed cause, devise a solution that can resolve the problem with minimal impact and risk. The solution may involve checking through each level of the OSI model to ensure that all layers are functioning properly and that there are no configuration errors, physical damages, or logical inconsistencies34
• Implement the solution: Execute the plan of action, and monitor the results. If the problem is not solved, revert to the previous state and create a new plan of action.
• Verify functionality: Confirm that the problem is fully resolved and that the network is restored to normal operation. Perform preventive measures if possible to avoid recurrence of the problem.
• Document the findings: Record the problem description, the solution, and the outcome. Update any relevant documentation, such as network diagrams, policies, or procedures.

References1: Troubleshooting Methods for Cisco IP Networks 2: Troubleshooting Methodologies - CBT IT Certification Training 3: How to use the OSI Model to Troubleshoot Networks 4: How is the OSI model used in troubleshooting? – Sage-Answer

iperf is a tool that can measure the bandwidth and quality of a network link by generating and transferring TCP or UDP data streams. iperf can report the maximum achievable throughput, packet loss, jitter, and other statistics for a given link. iperf can be used to test both the uplink and downlink performance of a network link by running it on two endpoints and specifying the direction and duration of the test. iperf can help the engineer verify that the new fiber uplink meets the throughput requirements for the office network.

tcpdump is a tool that can capture and analyze network traffic by filtering and displaying packets based on various criteria. tcpdump can help the engineer troubleshoot network problems, monitor network activity, and inspect packet contents, but it cannot measure the throughput or quality of a network link.

ping is a tool that can test the reachability and latency of a network host by sending and receiving ICMP echo packets. ping can help the engineer check if the new fiber uplink is connected and responsive, and how long it takes for packets to travel between the endpoints, but it cannot measure the throughput or quality of a network link.

netstat is a tool that can display information about the network connections, routing tables, interfaces, and protocols on a network host. netstat can help the engineer view the status and details of the network connections using the new fiber uplink, but it cannot measure the throughput or quality of a network link.

References

iperf - The ultimate speed test tool for TCP, UDP and SCTP

How to use iperf to test local network LAN speed in Windows 10

How to Test Network Performance Between Two Linux Servers

What is tcpdump?

8 Common Network Utilities Explained

Monitoring Your Network: ping, netstat, tcpdump, and Ethereal

Netstat vs. Nmap vs. Netcat: Understanding the Differences

The most likely reason why only eight cameras turn on is that the PoE switch does not have enough power budget to supply all 12 cameras. The engineer should check the voltage and wattage ratings of the PoE switch and the cameras, and make sure they are compatible and sufficient. The Ethernet cable type, transceiver compatibility, and DHCP addressing are less likely to cause this problem, as they would affect the data transmission rather than the power delivery.

References:

• CompTIA Network+ N10-008 Certification Study Guide, page 181
• CompTIA Network+ N10-008 Cert Guide, Deluxe Edition, page 352
• PoE Troubleshooting: The Common PoE Errors and Solutions3

 IP addresses beginning with 169.254. are called link-local addresses or APIPA (Automatic Private IP Addressing)1. They are assigned by the computer itself when it cannot reach a DHCP server to obtain a valid IP address from the network2. This can happen for several reasons, such as a faulty router, a misconfigured network, or a disconnected cable3.

To troubleshoot this issue, the technician should check the network settings, the router configuration, and the physical connection of the computer. The technician should also try to renew the IP address by using the command ipconfig /renew in Windows or dhclient in Linux. If the problem persists, the technician may need to contact the network administrator or the ISP for further assistance.

• Physical security is the protection of the physical assets and resources of an organization from unauthorized access, damage, or theft1.
• Physical security detection devices are devices that can monitor and alert on the presence or activity of intruders, unauthorized personnel, or environmental hazards in a physical location12.
• Cameras are examples of physical security detection devices, as they can capture and record video footage of the surroundings, and send alerts or notifications to the security personnel or the network administrator12.
• Cameras can also act as a deterrent for potential intruders, as they can make them aware that they are being watched and recorded2.
• The other options are not considered physical security detection devices, as they have different functions or purposes, such as:
• 1: CompTIA Network+ N10-008 Cert Guide, 1st Edition, Chapter 14: Network Security, pp. 566-569
• 2: CompTIA Network+ N10-008 Cert Guide, 1st Edition, Chapter 14: Network Security, p. 570
• 3: Access Control Vestibule - Wikipedia
• : CompTIA Network+ N10-008 Cert Guide, 1st Edition, Chapter 2: Network Devices, p. 67

2.4GHz frequency has better penetration and range than higher frequencies in forested environments, where there are many obstacles and interference sources.

References:

• Wireless in The Woods: Experimental Evaluation of IEEE 802.11a/b/g in Forested Environments1
• High-Speed Wireless Access in Forested Rural Areas Using Analog Radio Over Fiber2

Switch 1 and Switch 2 is the only two switches that can be configured. Only switches linked together with there switch ports needs to be "tagged" and "LACP" needs to be enabled. The other ports must be untagged with no LACP enabled. You only need to assign the correct vlan via each port. 'Speed and Duplex' needs to be Speed=1000 and Duplex=Full, with is by default.

https://resources.infosecinstitute.com/topic/what-are-tagged-and-untagged-ports/

Network Time Protocol (NTP) is a protocol used to maintain a highly accurate and reliable clock time on all devices within a network. NTP works by synchronizing the time of all the devices within a network to a single, highly accurate time source. This allows for the time of all the devices to be kept in sync with each other, ensuring a consistent and reliable time source for all devices within the network.

Crimping the cable as a straight-through cable is the most likely fix for the issue where users are unable to access any network resources after upgrading from Cat 5 to Cat 6 cables. Crimping is a process of attaching connectors to the ends of cables using a tool called a crimper. A straight-through cable is a type of twisted-pair cable that has the same wiring scheme on both ends, meaning that each pin on one end is connected to the same pin on the other end. A straight-through cable is used to connect devices that operate on different layers of the OSI model, such as a computer and a switch, or a switch and a router. If the newly installed cable is crimped with TIA/EIA 568A on one end and TIA/EIA 568B on the other end, it becomes a crossover cable. A crossover cable is a type of twisted-pair cable that has opposite wiring schemes on both ends, meaning that each pin on one end is connected to a different pin on the other end. A crossover cable is used to connect devices that operate on the same layer of the OSI model, such as two computers or two switches. Using a crossover cable instead of a straight-through cable can cause network communication errors or failures. References: [CompTIA Network+ Certification Exam Objectives], Straight Through vs Crossover Cable: What’s The Difference?

One possible cause of poor wireless performance is a bottleneck in the network, which means that other devices or applications are consuming too much bandwidth or resources and limiting the speed of the wireless access point. To troubleshoot this issue, the engineer should ensure that there is no congestion or interference from other devices on the network, such as wired clients, servers, routers, switches, or other wireless access points. The engineer can use tools such as network analyzers, bandwidth monitors, or ping tests to check the network traffic and latency12.

Another possible cause of poor wireless performance is outdated firmware on the device, which may contain bugs or vulnerabilities that affect the functionality or security of the wireless access point. To troubleshoot this issue, the engineer should install the latest firmware for the device from the manufacturer’s website or support portal. The engineer should follow the instructions carefully and backup the configuration before updating the firmware. The engineer can also check the release notes or changelog of the firmware to see if there are any improvements or fixes related to the wireless performance3 .

The other options are not relevant to troubleshooting poor wireless performance. Creating a new VLAN for the access point may help with network segmentation or security, but it will not improve the speed of the wireless connection. Making sure the SSID is not longer than 16 characters may help with compatibility or readability, but it will not affect the wireless performance. Configuring the AP in autonomous mode may give more control or flexibility to the engineer, but it will not enhance the wireless speed. Installing a wireless LAN controller may help with managing multiple access points or deploying advanced features, but it will not increase the wireless performance.

One of the features that can be configured to ensure that GRE overhead does not affect payload is A. jumbo frames. Jumbo frames are Ethernet frames that have a payload size larger than 1500 bytes, which is the standard maximum transmission unit (MTU) for Ethernet. By using jumbo frames, more data can be sent in each packet, reducing the overhead ratio and improving efficiency.

Auto medium-dependent interface (MDI), interface crossover, and collision detection are features related to Ethernet physical layer connectivity, but they do not affect GRE overhead or payload.

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.

An on-path attack is a type of attack where an attacker intercepts and modifies the traffic between two devices on the same network. One common example of an on-path attack is ARP poisoning, where an attacker sends fake ARP replies to trick the devices into sending their traffic to the attacker instead of the intended destination. This allows the attacker to eavesdrop, alter, or redirect the traffic.

To mitigate this threat, one of the best practices is to use dynamic ARP inspection (DAI), which is a security feature that validates ARP packets on a network. DAI checks the MAC address and IP address bindings in the ARP packets against a trusted database, such as the DHCP snooping table or a static ARP access list. If the ARP packet contains an invalid or spoofed binding, DAI drops the packet and prevents the ARP poisoning attack.

The other options are not as effective as DAI for mitigating on-path attacks. Role-based access is a method of controlling access to resources based on the roles and permissions of the users, but it does not prevent an attacker from spoofing the MAC address or IP address of a legitimate user. Control plane policing is a feature that protects the control plane of a router or switch from excessive or malicious traffic, but it does not verify the MAC address or IP address bindings in the data plane. MAC filtering is a feature that allows or denies access to a network based on the MAC address of the device, but it does not prevent an attacker from spoofing the MAC address of an allowed device.

References:

https://www.professormesser.com/security-plus/sy0-601/sy0-601-video/on-path-attacks/

https://www.cisco.com/c/en/us/td/docs/ios/12_2sb/feature/guide/cpp.html

Reducing the wireless power levels can limit the range of the guest wireless network and prevent users in an adjacent building from connecting to it. Adjusting the wireless channels or enabling wireless client isolation will not affect the signal strength or coverage of the guest network. Enabling wireless port security will not work on a guest network that does not use authentication or MAC address filtering. References: CompTIA Network+ Certification Exam Objectives Version 2.0 (Exam Number: N10-006), Domain 2.0 Network Operations, Objective 2.5 Given a scenario, implement appropriate wireless configuration settings; Guest WiFi Security - Cisco Umbrella

Port 5900 is the default port used by Virtual Network Computing (VNC), a graphical desktop-sharing system that allows remote access to another computer’s screen, keyboard and mouse1. VNC is one of the tools that can be used for remote troubleshooting of servers with high CPU usage, as it enables the technician to see the server’s desktop and perform actions on it. Port 5900 is also one of the ports listed in the CompTIA Network+ N10-008 exam objectives under the section "1.4 Given a scenario, use appropriate software tools to troubleshoot connectivity issues"2.

The other ports are not commonly used for remote access. Port 443 is used for Hypertext Transfer Protocol Secure (HTTPS), a secure version of HTTP that encrypts the communication between a web browser and a web server3. Port 3321 is used for Telepathy Broker Service, a service that provides communication between applications and telephony devices4. Port 8080 is used for HTTP Alternate, an alternative port for HTTP that is often used by web servers for testing or proxy purposes5.

References

1: Port 5900: What Is It Used for & How to Open It for RDP

2: Network+ (Plus) Certification | CompTIA IT Certifications

3: [What is HTTPS? - Definition from WhatIs.com]

4: [Telepathy Broker Service - Port 3321 - TCP/UDP]

5: [What is Port 8080? Why do some processes use this port?]

Decreasing the lease duration on the DHCP server will cause clients to renew their IP address leases more frequently, freeing up IP addresses for other clients to use. References: CompTIA Network+ Certification Study Guide, Chapter 3: IP Addressing.

A VoIP sales call with a customer would be most affected by jitter greater than 10ms on the WAN connection. Jitter is the variation in delay of packets arriving at the destination. It can cause choppy or distorted audio quality for VoIP applications, especially over WAN links that have limited bandwidth and high latency. The recommended jitter for VoIP is less than 10ms. References: https://www.voip-info.org/voip-jitter/

CPU utilization is a metric that measures the percentage of time a CPU spends executing instructions. When the logging level is set for debugging, the router may generate a large amount of logging data, which can increase CPU utilization and cause the router to stop responding to requests intermittently. References:

• Network+ N10-008 Objectives: 2.1 Given a scenario, troubleshoot common physical connectivity issues.

CRC errors are cyclic redundancy check errors that occur when data is corrupted during transmission. CRC errors are usually caused by physical layer issues such as faulty cables, connectors, ports, or interference. The network administrator will most likely start to troubleshoot at layer 1 of the OSI model, which is the physical layer that deals with the transmission of bits over a medium. References: CompTIA Network+ Certification Exam Objectives Version 2.0 (Exam Number: N10-006), Domain 4.0 Network Troubleshooting and Tools, Objective 4.1 Given a scenario, implement network troubleshooting methodology.

Two-factor authentication (2FA) is a method of verifying a user’s identity by requiring two pieces of evidence, such as something the user knows (e.g., a password) and something the user has (e.g., a token or a smartphone). 2FA adds an extra layer of security that makes it harder for hackers to access a user’s account by brute-force programs. Complex passwords are passwords that are long, random, and use a combination of uppercase and lowercase letters, numbers, and symbols. Complex passwords are more resistant to brute-force attacks than simple or common passwords. References: https://partners.comptia.org/docs/default-source/resources/comptia-network-n10-008-exam-objectives-(2-0), https://www.csoonline.com/article/3225913/what-is-two-factor-authentication-2fa-how-to-enable-it-and-why-you-should.html, https://www.howtogeek.com/195430/how-to-create-a-strong-password-and-remember-it/

A hot site is a fully redundant site that can take over operations immediately if the primary site goes down. In this scenario, the company has set up two different datacenters across the country that are current on data and applications, and they can immediately switch from one datacenter to another in case of an outage. References:

• Network+ N10-008 Objectives: 1.5 Compare and contrast disaster recovery concepts and methodologies.

When a user reports being unable to access network resources after making some changes, the network technician should first ask the user what changes were made. This information can help the technician identify the cause of the issue and determine the appropriate course of action.

References: CompTIA Network+ Certification Study Guide, Sixth Edition by Glen E. Clarke

NIC teaming is a technique that combines two or more network interface cards (NICs) on a server into a single logical interface that can increase bandwidth, provide redundancy, and balance traffic. NIC teaming can be configured with different modes and algorithms depending on the desired outcome. Link Aggregation Control Protocol (LACP) is a protocol that enables NIC teaming by dynamically bundling multiple links between two devices into one logical link. References: https://partners.comptia.org/docs/default-source/resources/comptia-network-n10-008-exam-objectives-(2-0), https://docs.microsoft.com/en-us/windows-server/networking/technologies/nic-teaming/nic-teaming

In a half-duplex link, devices can only send or receive data at one time, not simultaneously. Late collisions occur when devices transmit data at the same time after waiting for a clear channel. One of the causes of late collisions is excessive cable length, which increases the propagation delay and makes it harder for devices to detect collisions. The link termination, device configuration, and device hardware are not likely to cause late collisions on a half-duplex link.

First Hop Redundancy Protocol (FHRP) provides a failover mechanism for the default gateway, allowing a backup gateway to take over if the primary gateway fails. References: CompTIA Network+ Certification Study Guide, Chapter 4: Infrastructure.

QSFP+ is a transceiver type that can support up to 40Gbps. It stands for Quad Small Form-factor Pluggable Plus and uses four lanes of data to achieve high-speed transmission. It is commonly used for data center and high-performance computing applications. References: https://www.cisco.com/c/en/us/products/collateral/interfaces-modules/transceiver-modules/data_sheet_c78-660083.html

Wireless client isolation is a feature on wireless routers that limits the connectivity between wireless devices connected to the same network. It prevents them from accessing resources on other wireless or wired devices, as a security measure to reduce attacks and threats. This feature can be useful for guest and BYOD SSIDs, but it can also be disabled on the router’s settings. References: https://www.howtogeek.com/179089/lock-down-your-wi-fi-network-with-your-routers-wireless-isolation-option/

netstat -a is a command that displays information about active TCP connections and listening ports on a system. A network administrator can use netstat -a to check if the database engine is listening on a certain port, as well as verify if there are any connections established to or from that port. References: https://www.comptia.org/blog/what-is-netstat

Role separation is a security principle that involves dividing the tasks and privileges for a specific business process among multiple users. This reduces the risk of fraud and errors, as no one user has complete control over the process. In the scenario, there are three employees who perform very distinct functions on the server, which is an example of role separation. References: https://hyperproof.io/resource/segregation-of-duties/

This is the most likely cause of the user’s connection issues, because the ARP table of the switch shows that there are two devices with the same IP address of 192.168.1.10, but different MAC addresses. This indicates that there is an IP address conflict on the network, where two devices are trying to use the same IP address. This can cause intermittent connectivity issues, as the switch may not be able to forward packets to the correct destination .

A network technician is configuring a wireless network that consists of multiple APS for better coverage and allows roaming between the APS. Which of the following types of SSIDs should the technician configure?

• Basic Service Set
• Independent Basic Service Set
• Extended Service Set
• Distribution System Service

Answer: C

An extended service set (ESS) is a type of SSID that allows multiple access points (APs) to share the same SSID and provide seamless roaming for wireless clients. An ESS consists of two or more basic service sets (BSSs), which are individual APs with their own SSIDs. A distribution system (DS), such as a wired Ethernet LAN, connects the BSSs and enables data transfer between them. A wireless client can associate with any AP in the ESS and move from one BSS to another without losing connectivity or reauthenticating.

References:

• CompTIA Network+ N10-008 Certification Exam Objectives, page 51
• CompTIA Network+ Cert Guide: Wireless Networking, page 12

Which of the following passwords would provide the best defense against a brute-force attack?

• ThislsMyPasswordForWork
• Qwerty!@#$
• Password! 1
• T5!8j5

Answer: D

A brute-force attack is a method of guessing passwords by trying every possible combination of characters until the correct one is found. The longer and more complex the password, the harder it is to crack by brute-force. A password that provides the best defense against a brute-force attack should have a combination of uppercase and lowercase letters, numbers, and special characters, and should be as long as possible. The password T5!8j5 meets these criteria, while the other options are either too short, too simple, or too common.

References:

• Password Attacks – N10-008 CompTIA Network+ : 4.21
• CompTIA Network+ Cert Guide: Security Concepts and Tools, page 25

https://www.pearsonitcertification.com/articles/article.aspx?p=3021579 &seqNum=2

• Port security is a feature that allows switches to limit the number of MAC addresses that can be learned on a switchport, and to take action if an unauthorized MAC address is detected12.
• Port security can prevent rogue devices from connecting to the network and potentially launching attacks such as MAC spoofing, ARP poisoning, or VLAN hopping13.
• Port security can be configured to either drop packets from unauthorized MAC addresses (protect or restrict mode), or to shut down the port completely (shutdown mode)12.
• Port security can also be configured to use sticky MAC addresses, which are dynamically learned and stored in the running configuration, or to use static MAC addresses, which are manually entered and stored in the startup configuration12.
• Port security is a best practice for securing switchports that provide end user access, especially in public or untrusted areas, where rogue devices can be easily plugged in13.
• Spanning Tree Protocol (STP) is a network protocol that prevents loops in a switched network by disabling redundant links and creating a loop-free logical topology45.
• STP is not a control that would address the risk of rogue devices connecting to the network, as it does not limit the MAC addresses or the VLANs that can be learned on a switchport45.
• Deactivating STP on network interfaces that are facing public areas would not only be ineffective, but also counterproductive, as it would create the possibility of loops and broadcast storms if multiple devices are connected to the same switchport45.
• Neighbor Resolution Protocol (NRP) is not a valid term in networking. The closest term is Neighbor Discovery Protocol (NDP), which is an IPv6 protocol that performs functions such as address resolution, router discovery, prefix discovery, and neighbor unreachability detection67.
• NDP is not a control that would address the risk of rogue devices connecting to the network, as it does not limit the MAC addresses or the VLANs that can be learned on a switchport67.
• Disabling NDP in the Layer 2 devices would not only be ineffective, but also detrimental, as it would impair the IPv6 communication and functionality on the network67.
• Port tagging is a technique that adds a VLAN identifier (VID) to an Ethernet frame, indicating which VLAN it belongs to89.
• Port tagging is used to allow multiple VLANs to share the same physical link, such as a trunk port between switches, or a link to a device that supports VLAN tagging, such as a router or a server89.
• Port tagging is not a control that would address the risk of rogue devices connecting to the network, as it does not limit the MAC addresses or the VLANs that can be learned on a switchport89.
• Ensuring port tagging is in place for network interfaces in guest areas would not only be ineffective, but also unnecessary, as guest devices usually do not support VLAN tagging, and would only need access to a single VLAN89.

References:

• Port Security in Computer Network
• Understanding VLAN tagging and untagging of ports
• Spanning Tree Protocol
• Spanning Tree Protocol – CompTIA Network+ N10-007 – 1.3
• Spanning Tree Protocol – N10-008 CompTIA Network+ : 2.3
• Neighbor Discovery Protocol - NDP Overview
• Neighbor Discovery Protocol (NDP) – what is it?
• CompTIA Network+ domain #2: network implementation [2022 update]
• CompTIA Network+ Certification Exam Objectives

• The netstat -n command displays active TCP connections, but addresses and port numbers are expressed numerically and no attempt is made to determine names12. This option can be useful for checking the output in integer form, as well as for avoiding possible delays caused by name resolution12.
• The netstat command without any parameters displays active TCP connections, but addresses and port numbers are resolved to their corresponding names, such as hostnames and service names12. This option can be less informative and more time-consuming than the -n option12.
• The netstat -a command displays all active TCP connections and the TCP and UDP ports on which the computer is listening12. This option can be useful for checking the availability and status of ports, but it does not show the output in integer form12.
• The netstat -e command displays Ethernet statistics, such as the number of bytes and packets sent and received12. This option can be useful for checking the network performance and utilization, but it does not show the network connections or their addresses and port numbers12.

References:

• 1: CompTIA Network+ N10-008 Study Guide, Chapter 5: Network Tools and Troubleshooting
• 2: netstat | Microsoft Learn
• : 28 Netstat Commands {A Comprehensive List With Examples} - phoenixNAP
• : How to Use the Netstat Command - Lifewire

• A VLAN (Virtual Local Area Network) is a logical grouping of devices that share the same broadcast domain, regardless of their physical location or connection. VLANs can improve network performance, security, and management by separating different types of traffic, such as data, voice, and video1.
• A VoIP (Voice over Internet Protocol) phone is a device that uses the Internet to transmit voice calls, instead of the traditional phone lines. VoIP phones require a network connection, an IP address, and a gateway to communicate with other VoIP devices or phone systems2.
• A DHCP (Dynamic Host Configuration Protocol) server is a device that automatically assigns IP addresses and other network configuration parameters to devices that request them. DHCP simplifies network administration and avoids IP conflicts3.
• A switchport is a physical interface on a switch that connects to a network device, such as a VoIP phone, a computer, or another switch. A switchport can be configured to belong to a specific VLAN or to carry traffic from multiple VLANs4.
• A gateway is a device that connects different networks and enables communication between them. A gateway can also perform protocol conversion, such as translating between VoIP and analog signals5.
• A route is a path that a packet takes to reach its destination. A route consists of a destination network, a next-hop device, and a metric. A router is a device that forwards packets based on their destination IP addresses and the routing table.
• In order to allow a newly installed VoIP phone to operate correctly, the network administrator needs to assign the phone’s switchport to the correct VLAN. This will ensure that the phone can communicate with the DHCP server and obtain an IP address that belongs to the same network as the phone system. This will also isolate the voice traffic from the data traffic and improve the quality of service.
• Statically assigning the phone’s gateway address is not enough to allow the phone to operate correctly, as the phone still needs an IP address and a subnet mask to communicate with other devices on the network. Moreover, statically assigning network parameters can be tedious and prone to errors, especially for a large number of devices.
• Configuring a route on the VoIP network router is not necessary to allow the phone to operate correctly, as the phone and the phone system are on the same network and do not need to cross any routers. Configuring a route would only be needed if the phone and the phone system were on different networks and needed to communicate through a router.
• Implementing a VoIP gateway is not required to allow the phone to operate correctly, as the phone and the phone system are both VoIP devices and use the same protocol. Implementing a VoIP gateway would only be needed if the phone or the phone system needed to communicate with a non-VoIP device or system, such as a traditional phone line or a public switched telephone network (PSTN).

References:

• 1: VLAN
• 2: VoIP Phone
• 3: DHCP
• 4: Switchport
• 5: Gateway
• : [Route]
• : [VoIP VLAN Configuration]
• : [Static vs Dynamic IP Addressing]
• : [Routing Basics]
• : [VoIP Gateway]

• Channel overlap occurs when two or more wireless access points (APs) use the same or adjacent frequency channels within the same area12. This can cause interference and degradation of the wireless signal quality, resulting in increased latency and packet drops for the Wi-Fi-connected devices12.
• Channel overlap is one of the most common causes of Wi-Fi performance issues, especially in densely populated areas where there are many wireless networks operating in the same spectrum12. The 2.4 GHz band, which is widely used by Wi-Fi devices, has only three non-overlapping channels (1, 6, and 11) in most regions, making it more prone to channel overlap than the 5 GHz band, which has more non-overlapping channels available12.
• To fix channel overlap, network administrators should perform a site survey to identify the existing wireless networks and their channel usage, and then configure their APs to use the least congested or non-overlapping channels12. Alternatively, they can use APs that support automatic channel selection, which can dynamically adjust the channel based on the network conditions12.
• The other options are not the most likely reasons for the issue. Distance from the AP can affect the signal strength and quality, but it does not explain why the issue occurred only after the new company moved in3. Bandwidth latency is a measure of the delay in data transmission, which can be affected by various factors such as network congestion, routing, or quality of service, but it is not a cause of the issue itself4. RF attenuation is the loss of signal power due to distance, obstacles, or interference, which can also affect the Wi-Fi performance, but it is not specific to the scenario described in the question5. Network congestion is the state of high demand and low availability of network resources, which can cause latency and packet loss, but it is not necessarily related to channel overlap6. References:
• 1: CompTIA Network+ N10-008 Certification Study Guide, Chapter 4: Wireless Networks, Section 4.4: Wireless Network Troubleshooting7
• 2: Professor Messer’s CompTIA N10-008 Network+ Course Notes, Page 25: Wireless Troubleshooting8
• 3: CompTIA Network+ N10-008 Certification Study Guide, Chapter 4: Wireless Networks, Section 4.2: Wireless Network Implementations7
• 4: CompTIA Network+ N10-008 Certification Study Guide, Chapter 2: Network Protocols and Services, Section 2.5: Bandwidth and Latency7
• 5: CompTIA Network+ N10-008 Certification Study Guide, Chapter 4: Wireless Networks, Section 4.1: Wireless Network Fundamentals7
• 6: CompTIA Network+ N10-008 Certification Study Guide, Chapter 3: Routing, Section 3.5: Network Congestion7
• 7: CompTIA Network+ N10-008 Certification Study Guide2
• 8: Professor Messer’s CompTIA Network+ N10-008 Training Course5

Asymmetrical routing is the most likely cause for the WAN instability. When two different routing protocols are used, like OSPF and EIGRP, it can cause asymmetrical routing, which results in traffic being routed differently in each direction. This can lead to instability in the WAN. A CDP neighbor change, a switching loop, or an incorrect IP address are not likely causes for WAN instability.

OSPF uses multicast to communicate routing updates among routers within the same area. OSPF routers send and receive link-state advertisements (LSAs) using IP multicast addresses 224.0.0.5 (all OSPF routers) and 224.0.0.6 (all OSPF designated routers) 1. Multicast allows OSPF to send routing updates efficiently and selectively, without flooding the entire network or requiring acknowledgments from every router

• Jumbo frames are Ethernet frames that have a payload size larger than the standard 1500 bytes. They can range from 1501 to 9000 bytes, depending on the network device and configuration.
• Jumbo frames can reduce the overhead of file transfers by decreasing the number of frames that need to be sent and received, as well as the number of headers and checksums that need to be processed.
• Jumbo frames can also improve the throughput and efficiency of the network, as they reduce the fragmentation and reassembly of packets, and the CPU utilization of the network devices.
• However, jumbo frames also have some drawbacks, such as increased latency, higher memory requirements, and compatibility issues with some network devices and applications. Therefore, they should be used with caution and only when the network supports them.
• To enable jumbo frames, both the sender and the receiver, as well as all the intermediate devices (such as switches and routers) along the path, must support and be configured with the same maximum transmission unit (MTU) size. Otherwise, the frames will be dropped or fragmented, resulting in poor performance or errors.
• The other options are not relevant to reducing the overhead of file transfers:
• CompTIA Network+ N10-008 Study Guide, Chapter 2: Network Devices and Technologies, Section 2.3: Configure Switches, p. 97-98
• Professor Messer’s Network+ N10-008 Course Notes, Section 2.3: Switch Configuration, p. 22
• Professor Messer’s Network+ N10-008 Video Training Course, 2.3 Switch Configuration - Part 2

A CNAME (Canonical Name) record is a type of DNS (Domain Name System) record that maps an alias name to a canonical or true domain name. For example, a CNAME record can map blog.example.com to example.com, which means that blog.example.com is an alias of example.com. A CNAME record is useful when you want to point multiple subdomains to the same IP address, or when you want to change the IP address of a domain without affecting the subdomains1.

A PTR (Pointer) record is used to map an IP address to a domain name, which is necessary for reverse lookup checks. Reverse lookup checks are performed by external mail servers to verify the identity of the sender of the email. By configuring a PTR record, the network technician can ensure that the company's external mail server can pass these checks. According to the CompTIA Network+ Study Guide, "A PTR record is used to map an IP address to a domain name, and it is often used for email authentication."

A site-to-site VPN is a type of VPN that connects two or more networks over the Internet using a secure tunnel. A site-to-site VPN allows users to access network resources on a laptop without logging in to the VPN application, as long as the laptop is connected to one of the networks in the VPN. A site-to-site VPN is transparent to the users and does not require any additional software or configuration on the client devices.

References: Network+ Study Guide Objective 3.4: Explain the purposes and use cases for VPNs.

A break in the cable means that there is no electrical continuity between the two ends of the cable, which prevents the signal from reaching the switch. A tone generator is a device that sends an audible signal through the cable, and if no tone is heard at the far end, it indicates a break in the cable.

The transceivers labeled 8Gbps are likely to be used with the Fibre Channel protocol. Fibre Channel is a high-speed networking technology that is primarily used to connect storage devices to servers in storage area networks (SANs). It is capable of transmitting data at speeds of up to 8 Gbps (gigabits per second), and uses specialized transceivers to transmit and receive data over fiber optic cables.

Coaxial over Ethernet (CoE) is a networking technology that uses coaxial cables to transmit data, and is not related to the transceivers in question. Internet Small Computer Systems Interface (iSCSI) is a protocol that allows devices to communicate over a network using the SCSI protocol, and does not typically use specialized transceivers. Gigabit interface converter (GBIC) is a type of transceiver used to transmit and receive data over fiber optic cables, but it is not capable of transmitting data at 8 Gbps.

802.11b is a wireless networking standard that operates on the 2.4 GHz frequency band. It supports a maximum data rate of 11 Mbps and has a range of about 35 meters indoors and 140 meters outdoors. 802.11b is compatible with older smart-plug devices that use the same frequency band, but it may suffer from interference from other devices that also use the 2.4 GHz band, such as microwave ovens, Bluetooth devices, and cordless phones.

Before disposing of a network router, it is important to back up and erase the configuration to prevent unauthorized access to sensitive data and network settings. A network router may contain information such as passwords, IP addresses, firewall rules, VPN settings, and other network parameters that could be exploited by hackers or malicious users. By backing up the configuration, you can preserve the network settings for future reference or reuse. By erasing the configuration, you can wipe out the data and restore the router to its factory default state.

Traffic shaping is a congestion management method that regulates network data transfer by delaying the flow of less important or less desired packets1. Traffic shaping can help to improve the performance of a videoconferencing application by prioritizing its packets over other types of traffic and smoothing out traffic bursts. Traffic shaping can also help to avoid packet loss and ensure fair allocation of bandwidth among different applications or users.

Flow control is a mechanism that prevents a sender from overwhelming a receiver with more data than it can handle. Flow control can help to avoid buffer overflow and data loss, but it does not prioritize different types of traffic or smooth out traffic bursts. Flow control operates at the data link layer or the transport layer, while traffic shaping operates at the network layer or above.

NetFlow is a protocol that collects and analyzes network traffic data for monitoring and troubleshooting purposes2. NetFlow can help to identify the sources, destinations, volumes, and types of traffic on a network, but it does not regulate or shape the traffic flow. NetFlow operates at the network layer or above.

Link aggregation is a technique that combines multiple physical links into one logical link for increased bandwidth, redundancy, and load balancing. Link aggregation can help to improve the performance of a videoconferencing application by providing more available bandwidth at the WAN connection, but it does not prioritize different types of traffic or smooth out traffic bursts. Link aggregation operates at the data link layer.

An ARP request operates at the data link layer of the OSI model. ARP (Address Resolution Protocol) is a protocol that maps IP addresses to MAC addresses on a local area network. It allows devices to communicate with each other without knowing their MAC addresses beforehand. ARP operates at the data link layer (layer 2) of the OSI model, which is responsible for framing and addressing data packets on a physical medium. References: https://www.cisco.com/c/en/us/support/docs/ip/routing-information-protocol-rip/13788-3.html

Role-based access is a security capability that assigns permissions to users based on their roles or functions within an organization. It allows the network administrator to maintain these permissions with the least administrative effort, as they only need to configure the security groups for each role once and then assign users to those groups. Mandatory access control is a security capability that assigns permissions based on security labels or classifications, which requires more administrative effort to maintain. User-based permissions are a security capability that assigns permissions to individual users, which is not scalable or efficient for large organizations. Least privilege is a security principle that states that users should only have the minimum level of access required to perform their tasks, which is not a security capability by itself.

RG6 is a type of coaxial cable that is commonly used for cable TV and internet services. A cable modem is a device that modulates and demodulates signals over a coaxial cable network to provide broadband internet access. A SOHO situation refers to a small office/home office environment that typically has a single cable modem connected to a single coaxial cable outlet. Therefore, RG6 is the most appropriate demarcation connection for a cable modem in a SOHO situation. References: [CompTIA Network+ Certification Exam Objectives], What Is RG6 Cable? | Techwalla

A site-to-site VPN is a method that creates a secure and encrypted connection between two internet gateways, such as routers or firewalls, that belong to different networks1. A site-to-site VPN can secure all traffic between a branch office and its data center by creating a virtual tunnel that protects the data from interception or tampering. A site-to-site VPN can also provide a zero-touch experience for all staff members who work there, as they do not need to install any software or configure any settings on their devices to access the data center resources. They can simply use their local network as if they were physically connected to the data center network.

VNC (Virtual Network Computing) is a method that allows remote access and control of a computer’s desktop from another device over a network2. VNC can enable staff members to work remotely by accessing their office computers from their home computers or mobile devices. However, VNC does not secure all traffic between a branch office and its data center, as it only works at the application layer and does not encrypt the network layer. VNC also does not provide a zero-touch experience for staff members, as they need to install software and configure settings on both the host and the client devices.

Remote desktop gateway is a method that allows remote access and control of a computer’s desktop from another device over a network using the Remote Desktop Protocol (RDP). Remote desktop gateway can also enable staff members to work remotely by accessing their office computers from their home computers or mobile devices. However, remote desktop gateway does not secure all traffic between a branch office and its data center, as it only works at the application layer and does not encrypt the network layer. Remote desktop gateway also does not provide a zero-touch experience for staff members, as they need to install software and configure settings on both the host and the client devices.

Virtual LANs (VLANs) are methods that create logical subdivisions of a physical network based on criteria such as function, department, or security level. VLANs can improve network performance, security, and management by reducing broadcast domains, isolating traffic, and enforcing policies. However, VLANs do not secure all traffic between a branch office and its data center, as they only work at the data link layer and do not encrypt the network layer. VLANs also do not provide a zero-touch experience for staff members, as they need to configure settings on their network devices to join or leave a VLAN.

Role-based access is a security technique that assigns permissions and privileges to users or groups based on their roles or functions within an organization. Role-based access can help secure the physical networking equipment by limiting who can access, modify, or manage the devices in the shared IT closet. Only authorized personnel with a valid role and credentials should be able to access the networking equipment. Disabling unneeded switchports is a security technique that prevents unauthorized devices from connecting to the network by turning off unused ports on a switch. Changing the default passwords is a security technique that prevents unauthorized access to network devices by replacing the factory-set passwords with strong and unique ones. Configuring an access control list is a security technique that filters network traffic by allowing or denying packets based on criteria such as source and destination IP addresses, ports, or protocols.

References: CompTIA Network+ Certification Exam Objectives Version 7.0 (N10-007), Objective 3.2: Given a scenario, use appropriate network hardening techniques.

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

In DNS, the PTR (Pointer) record is used specifically in reverse DNS lookups to map an IP address to a domain name, which is the opposite of the more common forward DNS lookups that map domain names to IP addresses. The PTR record is the principal type of record used in reverse DNS lookups, making it the correct answer. AAAA records store IPv6 addresses, CNAME records are used for aliases, and TXT records hold text information, none of which are primarily used in reverse DNS configurations​​.

FTP (File Transfer Protocol) is a client-server based protocol, meaning that the two computers involved communicate with each other in a request-response pattern. The client sends a request to the server and the server responds with the requested data. This type of architecture is known as client-server, and it is used for many different types of applications, including FTP. Other architectures, such as service-oriented, connection-oriented, and data-centric, are not used for FTP.

• A DHCP scope is a range of IP addresses that a DHCP server can assign to clients on a network.
• If the DHCP scope is fully utilized, it means that there are no more available IP addresses to assign to new clients.
• This can cause some internal users who cannot connect to network resources, as they will not have a valid IP address to communicate with other devices on the network.
• The users may have been able to connect last week, but not today, because their previous IP address lease may have expired and they could not renew it due to the lack of available IP addresses.
• The other options are less likely to cause the issue, because:

References:

• : CompTIA Network+ N10-008 Study Guide, Chapter 3: IP Addressing, page 104
• : Professor Messer’s CompTIA N10-008 Network+ Course Notes, Section 3.2: DHCP, page 27
• : CompTIA Network+ N10-008 Study Guide, Chapter 2: Network Cabling and Topologies, page 69
• : Professor Messer’s CompTIA N10-008 Network+ Course Notes, Section 4.1: Network Services, page 36
• : CompTIA Network+ N10-008 Study Guide, Chapter 7: Network Management, page 276
• : Professor Messer’s CompTIA N10-008 Network+ Course Notes, Section 7.1: Network Monitoring, page 66

The cause of the connection issue is a routing loop. A routing loop is a situation where a packet is forwarded in circles between routers, never reaching its destination. A routing loop can be caused by misconfigured or inconsistent routing tables, or by routing protocols that do not update their information properly. A routing loop can be detected by using the traceroute command, which shows the path taken by a packet from the source to the destination. The traceroute output in the image shows that the packet is bouncing back and forth between two routers, 10.12.2.1 and 10.12.2.2, indicating a routing loop. References: CompTIA Network+ N10-008 Certification Study Guide, page 181; The Official CompTIA Network+ Student Guide (Exam N10-008), page 7-9.

East-west data traffic in a data center refers to the traffic that flows laterally within the data center, typically between servers within the same data center. This type of traffic usually flows between top-of-rack (ToR) switches, which connect multiple servers or devices in the same rack to each other or to other racks without necessarily routing through the core or distribution layers of the network architecture. This is opposed to north-south traffic, which typically flows in and out of the data center to the wider network or internet. Therefore, the correct answer is "top-of-rack switches"​​.

A long-range microwave interface is a type of wireless communication that uses high-frequency radio waves to transmit and receive data over long distances. A long-range microwave interface typically uses a parabolic antenna, also known as a dish antenna, to focus the radio waves into a narrow beam that can travel farther and with less interference than an omnidirectional antenna, which radiates the radio waves in all directions1.

One of the most common causes of input errors on a long-range microwave interface is the misalignment of the parabolic antenna. Input errors are errors that occur when the receiver cannot properly decode or process the incoming signal. If the parabolic antenna is not aligned correctly with the transmitter, the receiver may not be able to capture the full strength of the signal, or it may pick up unwanted noise or interference from other sources. This can result in corrupted or lost data, which will increase the input error count23.

To troubleshoot this issue, the junior network administrator should check the alignment of the parabolic antenna and make sure it is pointing directly at the transmitter. The administrator can use tools such as a spectrum analyzer, a signal strength meter, or a path alignment tool to measure and adjust the signal quality and alignment of the antenna24.

The other options are not likely reasons for the input errors on a long-range microwave interface. A long-range microwave interface does not use an omnidirectional signal, so it cannot be jammed or weakened by other sources. The parabolic signal does not depend on the routing protocols used by the network, so it cannot be affected by improper routing protocols.

• A VLAN is a virtual local area network that logically separates devices on the same physical network. VLANs can improve network performance, security, and management by reducing broadcast domains and isolating traffic.
• A DHCP reservation is a feature that allows a network administrator to assign a specific IP address to a device based on its MAC address. This ensures that the device always receives the same IP address from the DHCP server, even if the lease expires or the device reboots.
• A networked printer is a device that can be shared by multiple users on the same network. A networked printer typically has a built-in network interface card (NIC) that allows it to communicate with other devices using TCP/IP protocols.
• A print server is a device or a software application that manages the printing requests from multiple clients. A print server can also provide additional features such as print queue management, printer driver installation, and printer status monitoring.
• A subnet is a logical division of an IP network that allows devices to communicate more efficiently and securely. A subnet is defined by a network address and a subnet mask, which determine the range of valid IP addresses within the subnet. Devices on the same subnet can communicate directly with each other without the need for a router.
• A ping is a network diagnostic tool that tests the connectivity and reachability between two devices by sending and receiving echo packets. A ping request can fail for various reasons, such as network congestion, firewall settings, routing issues, or device configuration errors.
• Based on the question, the networked printer is unavailable because it cannot be pinged from the print server in the same subnet. This means that there is a problem with the layer 2 connectivity between the two devices, which is determined by the MAC addresses and the VLANs. The most likely cause of this problem is that the printer and the print server are on different VLANs, which prevents them from communicating with each other. The other options are less likely because they affect the layer 3 connectivity, which is determined by the IP addresses and the gateways. A DNS failure would not affect the ping request, since it uses IP addresses and not hostnames. A DHCP scope exhaustion would not affect the printer, since it has a DHCP reservation that guarantees its IP address. An incorrect gateway would not affect the communication within the same subnet, since it is only used for routing packets to other networks. References:
• CompTIA Network+ N10-008 Study Guide, Chapter 2: Network Devices and Technologies, Section 2.2: Network Device Functions and Features, Subsection: Print Servers, pp. 76-77.
• CompTIA Network+ N10-008 Study Guide, Chapter 3: Network Operations, Section 3.3: Network Configuration Management, Subsection: DHCP, pp. 144-146.
• CompTIA Network+ N10-008 Study Guide, Chapter 4: Network Security, Section 4.2: Network Segmentation and Isolation, Subsection: VLANs, pp. 202-204.
• Professor Messer’s CompTIA N10-008 Network+ Course Notes, Section 1.5: Network Troubleshooting Methodology, Subsection: Identify the Problem, pp. 16-17.
• Professor Messer’s CompTIA N10-008 Network+ Course Notes, Section 2.2: Network Devices, Subsection: Print Servers, p. 28.
• Professor Messer’s CompTIA N10-008 Network+ Course Notes, Section 2.6: Network Addressing, Subsection: DHCP, p. 38.
• Professor Messer’s CompTIA N10-008 Network+ Course Notes, Section 2.7: Network Addressing, Subsection: Subnetting, p. 39.
• Professor Messer’s CompTIA N10-008 Network+ Course Notes, Section 3.5: Network Segmentation, Subsection: VLANs, p. 58.

A duplex mismatch is the most probable cause of the issues described, where the network connection experiences slow data transfers and intermittent lockups. This occurs when one device in a network connection operates in full-duplex mode and the other in half-duplex, leading to collisions and performance issues. In the scenario provided, the small switch taken from storage may not have been configured to match the duplex settings of the existing network, resulting in these data transfer issues. Other options like reversed TX/RX pinouts, cable crosstalk, or a failed transceiver would typically result in complete connection failures or consistent degradation, not intermittent issues as described​​.

• An access control list (ACL) is a set of rules that defines which traffic is allowed or denied on a network device, such as a router or a firewall12.
• An ACL can be used to filter traffic based on various criteria, such as source or destination IP address, port number, protocol, or time of day12.
• By implementing an ACL on the edge router of the network, the network administrator can block the unauthorized IP address from entering the secure part of the network every night at 8:00 pm12.
• This solution would address the concerns of the network administrator, as it would prevent the unauthorized IP address from accessing the critical server or any other resource on the secure network12.
• Changing the VLAN of the web server (A) or changing the server’s IP address (B) would not stop the unauthorized IP address from entering the network, as it could still scan the network for other open ports or vulnerabilities12.
• Instating a rule on the firewall connected to the web server (D) would only protect the web server, but not the rest of the secure network, from the unauthorized IP address12. References:
• CompTIA Network+ N10-008 Certification Study Guide, Chapter 4: Network Operations, Section 4.3: Network Security Devices and Technologies, pp. 212-213.
• Professor Messer’s CompTIA N10-008 Network+ Course, Section 4.3: Network Security Devices and Technologies, Video: Access Control Lists.

It does this by using a two-level hierarchy of switches, where the spine switches connect to the leaf switches, which in turn connect to the end hosts. This reduces the number of hops a packet must take from one host to another, thus reducing latency. According to the CompTIA Network+ N10-008 Exam Guide, the Spine and Leaf topology is a modern architecture that is used to reduce latency in large networks.

Channel bonding is a technique that allows two or more adjacent channels to be combined into a wider channel, increasing the data rate and throughput of the wireless network. Channel bonding can improve the performance of the Wi-Fi network by utilizing more of the available spectrum and reducing interference from other devices. Channel bonding is supported by Wi-Fi 5 (802.11ac) and Wi-Fi 6 (802.11ax) standards.

References: CompTIA Network+ N10-008 Cert Guide, Chapter 4, Section 4.2

Access points (APs) can be configured and centrally managed using a wireless LAN controller (WLC). A WLC is a device that connects to multiple APs and provides centralized management and control of those APs. The WLC can be used to configure settings such as wireless network parameters, security settings, and quality of service (QoS) policies. Additionally, the WLC can be used to monitor the status of connected APs, track client connections, and gather statistics on network usage. Some vendors such as Cisco, Aruba, Ruckus, etc. provide wireless LAN controllers as part of their wireless networking solutions.

• A proxy server is an intermediary server that acts as a gateway between the internet and the users. It has its own IP address, so the internet activities appear to be coming from the proxy server instead of the users’ devices1.
• A proxy server can provide several benefits, such as caching web pages, filtering content, bypassing geo-restrictions, and enhancing privacy and security1.
• A proxy server can be configured to allow or deny access to certain websites or protocols based on the corporate network policy1.
• A VPN client is a software application that creates an encrypted tunnel between the user’s device and a VPN server. A VPN client can also change the user’s IP address, but it does so for the entire operating system, not just for specific applications2.
• A VPN client can provide more security and privacy than a proxy server, but it also requires more resources and may slow down the internet connection2.
• A VPN client is usually used to access remote networks or bypass censorship, not to comply with corporate network policy2.
• A bridge is a network device that connects two or more network segments and forwards data frames based on their MAC addresses3.
• A bridge can increase the performance and security of a network by reducing collisions and filtering traffic3.
• A bridge does not change the IP address of the users or the network segments, nor does it provide any gateway function to the internet3.
• A bridge is usually used to extend or segment a local area network (LAN), not to connect to the internet3.
• A VLAN is a logical grouping of network devices that share the same broadcast domain, regardless of their physical location or connection.
• A VLAN can improve the performance, security, and management of a network by reducing broadcast traffic, isolating network segments, and enforcing access control policies.
• A VLAN does not change the IP address of the users or the network devices, nor does it provide any gateway function to the internet.
• A VLAN is usually used to create subnetworks within a LAN, not to connect to the internet.

References:

• Proxy vs. VPN: What Is the Difference? | Fortinet
• What’s the difference between a proxy server and a VPN? | Windows Central
• Bridge (networking) - Wikipedia
• [VLAN (Virtual Local Area Network) - Definition from Techopedia]

A reservation is a feature of DHCP that assigns a specific IP address to a device based on its MAC address. This way, the device will always receive the same IP address from the DHCP server, regardless of its location or connection time. A network administrator can set up a reservation for each loT device to accomplish the requirements of reducing manual configuration, assigning a specific IP address, and allowing devices to move to different switchports on the same VLAN. References: https://www.comptia.org/blog/what-is-dhcp

255.255.252.0 is a subnet mask that allows for 1022 network-connected devices on the same subnet, which is the smallest subnet that can accommodate 412 devices. The subnet mask determines how many bits are used for the network portion and how many bits are used for the host portion of an IP address. A smaller subnet mask means more bits are used for the network portion and less bits are used for the host portion, which reduces the number of available hosts on the subnet. 255.255.0.0 allows for 65534 hosts on the same subnet, which is too large. 255.255.254.0 allows for 510 hosts on the same subnet, which is also too large. 255.255.255.0 allows for 254 hosts on the same subnet, which is too small.

The antenna type affects the signal strength and coverage of a WAP. Different types of antennas have different radiation patterns and gain, which determine how far and wide the signal can reach. If the user experiences a weak signal in one direction but a strong signal in the opposite direction, it could mean that the antenna type is not suitable for the desired coverage area. The technician should consider changing the antenna type to one that has a more balanced or directional radiation pattern. References: https://community.cisco.com/t5/wireless-small-business/wap200-poor-signal-strength/td-p/1565796

A door lock would be the best security device to use to provide mechanical access control to the MDF/IDF. A door lock is a device that prevents unauthorized access to a physical area by requiring a key, a code, a card, a biometric scan, or a combination of these factors to open it. A door lock can provide mechanical access control to the MDF/IDF, which are rooms that house network equipment such as switches, routers, servers, or patch panels. A door lock can prevent unauthorized persons from tampering with or stealing the network equipment or data. References: https://www.cisco.com/c/en/us/td/docs/solutions/Enterprise/Data_Center/DC_Infra2_5/DCInfra_6.html

Ransomware is a type of malware that encrypts user data and demands a ransom for its decryption. Ransomware can prevent users from accessing their files and applications, and cause data loss or corruption. A proper backup implementation is essential to recover from a ransomware attack, as it can help restore the encrypted data without paying the ransom or relying on the attackers’ decryption key. References: https://www.comptia.org/blog/what-is-ransomware

DNS poisoning is a type of attack that modifies the DNS records of a domain name to point to a malicious IP address instead of the legitimate one. This can result in users being directed to cloned websites that are stealing credentials, even if they enter the correct URL for the website. The incorrect DNS server address on the user’s PC could be a sign of DNS poisoning, as the attacker could have compromised the DNS server or spoofed its response to redirect the user’s queries. References: https://www.comptia.org/blog/what-is-dns-poisoning

A VLAN mismatch is the most likely reason why an IP phone does not receive the necessary DHCP options for registration. A VLAN mismatch occurs when a device is connected to a switch port that belongs to a different VLAN than the device’s intended VLAN. This can cause communication problems or prevent access to network resources. For example, if an IP phone is connected to a switch port that belongs to the data VLAN instead of the voice VLAN, it may not receive the DHCP options that contain information such as the TFTP server address, the NTP server address, or the default gateway address for the voice VLAN. These DHCP options are essential for the IP phone to register with the VoIP system and function properly. References: https://www.cisco.com/c/en/us/support/docs/voice-unified-communications/unified-communications-manager-callmanager/13979-dhcp-option-150-00.html

Consistent labeling would be the concept that would best help the technician to confirm which switchport corresponds to the wall jack the PC is using. Consistent labeling is a practice of using standardized and descriptive labels for network devices, ports, cables, jacks, and other components. It can help with identifying, locating, and troubleshooting network issues. For example, a technician can use consistent labeling to trace a cable from a PC to a wall jack, and then from a patch panel to a switchport. References: https://www.cisco.com/c/en/us/td/docs/solutions/Enterprise/Data_Center/DC_Infra2_5/DCInfra_6.html

Implicit deny is a firewall rule that blocks all traffic that is not explicitly allowed by other rules. Implicit deny is usually applied as the last rule in the firewall to ensure that only the necessary access requirements are allowed through the firewall and that any unwanted or malicious traffic is rejected. Implicit deny can also provide a default security policy and a baseline for auditing and logging purposes.

Secure SNMP is a protocol that allows network devices to send event messages to a centralized server or console for logging and analysis. Secure SNMP can be used to monitor and manage the status, performance, and configuration of network devices. Secure SNMP can also help to detect and respond to potential problems or faults on the network. However, secure SNMP is not a firewall rule; it is a network management protocol.

Port security is a feature that allows a switch to restrict the devices that can connect to a specific port based on their MAC addresses. Port security can help to prevent unauthorized access, spoofing, or MAC flooding attacks on the switch. However, port security is not a firewall rule; it is a switch feature.

DHCP snooping is a feature that allows a switch to filter DHCP messages and prevent rogue DHCP servers from assigning IP addresses to devices on the network. DHCP snooping can help to prevent IP address conflicts, spoofing, or denial-of-service attacks on the network. However, DHCP snooping is not a firewall rule; it is a switch feature.

Giants are packets that exceed the configured MTU (Maximum Transmission Unit) of a switchport or interface, which causes them to be dropped or fragmented by the switch or router. The MTU is the maximum size of a packet that can be transmitted without fragmentation on a given medium or protocol. Giants can indicate misconfiguration or mismatch of MTU values between devices or interfaces on a network, which can cause performance issues or errors. CRC errors are errors that occur when the cyclic redundancy check (CRC) value of a packet does not match the calculated CRC value at the destination, which indicates corruption or alteration of data during transmission due to noise, interference, faulty cabling, etc., but not necessarily exceeding MTU values. Runts are packets that are smaller than the minimum size allowed by the medium or protocol, which causes them to be dropped or ignored by the switch or router. Flooding is a technique where a switch sends packets to all ports except the source port when it does not have an entry for the destination MAC address in its MAC address table, which can cause congestion or broadcast storms on a network.

TACACS+ is a protocol that provides centralized authentication, authorization, and accounting (AAA) for network devices and users. TACACS+ can help improve the security of the management console on the company’s switches by verifying the identity and credentials of the administrators, enforcing granular access policies and permissions, and logging the configuration changes made by each administrator. This way, the network administrator can ensure only authorized and authenticated users can access and modify the switch settings, and also track and correlate the changes made by each user. References: https://www.comptia.org/blog/what-is-tacacs

IaaS stands for Infrastructure as a Service, which is a cloud computing model that provides virtualized computing resources such as servers, storage, and networking over the Internet. When implementing IaaS, the network technician should consider the server hardware requirements, such as CPU, RAM, disk space, and network bandwidth, that are needed to run the applications and services on the cloud. The other options are not relevant to IaaS, as they are either handled by the cloud provider or by the end-user. References: https://www.comptia.org/blog/what-is-iaas

AUP stands for Acceptable Use Policy, which is a policy that defines the rules and guidelines for using a network or service. A guest captive portal is a web page that requires users to agree to the AUP before accessing the Internet or other network resources. This is a common way to enforce security and legal compliance for guest users. References: https://www.arubanetworks.com/techdocs/Instant_87_WebHelp/Content/instant-ug/captive-portal/captive-portal.htm

A warm site is a type of disaster recovery site that has equipment ready to go in the event of a disaster at the main datacenter, but does not have live data or applications. A warm site requires some time and effort to restore the data and services from backups, but it is less expensive than a hot site that has live data and applications. A cold site is a disaster recovery site that has no equipment or data, and requires a lot of time and money to set up after a disaster. A cloud site is a disaster recovery site that uses cloud computing resources to provide data and services, but it may have issues with bandwidth, latency, security, and cost. References: https://www.comptia.org/blog/what-is-a-warm-site

A technique used to adjust resources dynamically for a virtual web server under variable loads is called auto-scaling. Auto-scaling automatically increases or decreases the number of instances of a virtual web server in response to changes in demand, ensuring that the right amount of resources are available to handle incoming traffic. This can help to improve the availability and performance of a web application, as well as reduce costs by avoiding the need to provision and maintain excess capacity.

The most likely cause of outages due to newly installed hardware is a misconfiguration of the device settings. Therefore, the first step should be to review the device configuration and check for any errors or inconsistencies that might affect the WAN connectivity.

References: Network+ Study Guide Objective 2.1: Explain the importance of network documentation.

Load balancing is a technique that can be used to provide fault tolerance and high performance while appearing as one URL to users. It is achieved by distributing the workload across multiple servers, which are usually located in different geographical locations. This allows for high performance and fault tolerance, as if one server fails, the other will take its place. Additionally, the multiple servers appear as one URL to the users, eliminating the need for the users to switch between servers.

 A denial-of-service (DoS) attack is an example of an attack where an attacker sends more connection requests than a server can handle, causing the server to crash. A DoS attack is a type of cyberattack that aims to disrupt the normal functioning of a network service or resource by overwhelming it with excessive or malformed traffic. A DoS attack can prevent legitimate users from accessing the service or resource, resulting in degraded performance, unavailability, or data loss. A DoS attack can target various network layers, protocols, or components, such as servers, routers, firewalls, or applications. References: [CompTIA Network+ Certification Exam Objectives], What Is a Denial-of-Service (DoS) Attack? | Cisco

To assign IPv6 addresses without DHCP, the technician can use SLAAC (Stateless Address Autoconfiguration). Here’s why:

• SLAAC: Stateless Address Autoconfiguration allows devices to automatically configure their IPv6 addresses based on the network prefix advertised by routers. It doesn’t rely on a central DHCP server for address assignment.
• APIPA (Automatic Private IP Addressing): This is an IPv4 feature and not applicable for IPv6.
• MAC reservation: This is related to DHCP and doesn’t directly assign IPv6 addresses.
• IPv4 to IPv6 tunnel: This is used for tunneling IPv6 traffic over an IPv4 network and doesn’t address address assignment.

Therefore, the correct answer is A. SLAAC

• A VLAN (virtual local area network) is a logical grouping of devices that share the same broadcast domain, regardless of their physical location or connection.
• VLANs can be used to separate different types of traffic on a network, such as data, voice, video, etc.
• VLANs can also improve network performance, security, and management by reducing the size of broadcast domains and limiting unnecessary traffic.
• To pass both data and telephony on an access port, the network engineer needs to configure the port as a trunk port, which can carry multiple VLANs using tags.
• The network engineer also needs to assign the data and voice devices to different VLANs, and enable quality of service (QoS) to prioritize the voice traffic over the data traffic.
• VoIP (voice over IP) is a technology that allows voice communication over an IP network, such as the Internet. VoIP is not a feature that can be configured on an access port, but rather a type of traffic that can be carried by a VLAN.
• VIP (virtual IP) is an IP address that is shared by multiple devices or servers, usually for load balancing or redundancy purposes. VIP is not a feature that can be configured on an access port, but rather a type of address that can be assigned to a device or server.
• VRRP (virtual router redundancy protocol) is a protocol that allows multiple routers to form a virtual router group and provide backup for each other in case of failure. VRRP is not a feature that can be configured on an access port, but rather a protocol that can be implemented on a router.

References:

• CompTIA Network+ N10-008 Study Guide, Chapter 3: Deploying Ethernet Switching, Section 3.2: VLANs and Trunking, pp. 111-1201
• Professor Messer’s CompTIA N10-008 Network+ Course Notes, Section 3.2: VLANs and Trunking, pp. 28-292
• Professor Messer’s CompTIA N10-008 Network+ Training Course, Video 3.2: VLANs and Trunking3

The lab environment is located in the DMZ, and traffic to the LAN zone is denied by default. This is the most likely reason why the web server cannot retrieve files from the file server, and the technician can either move the computer to another zone or request an exception from the administrator to resolve the problem. A DMZ (Demilitarized Zone) is a network segment that separates the internal network (LAN) from the external network (Internet). It usually hosts public-facing servers such as web servers, email servers, or FTP servers that need to be accessed by both internal and external users. A firewall is used to control the traffic between the DMZ and the LAN zones, and usually denies traffic from the DMZ to the LAN by default for security reasons. Therefore, if a web server in the DMZ needs to communicate with a file server in the LAN, it would need a special rule or permission from the firewall administrator. References: https://www.cisco.com/c/en/us/support/docs/ip/access-lists/13608-21.html

A wireless controller would be able to handle the requirement of implementing a large number of WAPs throughout the building and allowing users to move around without dropping their connections. A wireless controller is a device that centrally manages and configures multiple wireless access points (WAPs) on a network. It can provide features such as load balancing, roaming, security, QoS, and monitoring for the wireless network. A wireless controller can also support wireless mesh networks, where some WAPs act as relays for other WAPs to extend the wireless coverage. References: https://www.cisco.com/c/en/us/products/wireless/wireless-lan-controller/index.html

An omni antenna should be used by the AP to provide service in a radius surrounding a radio. An omni antenna is a type of antenna that has a 360-degree horizontal radiation pattern. It can provide wireless coverage in all directions from the antenna with varying degrees of vertical coverage. It is suitable for indoor environments where users are located around the AP1. References: https://www.cisco.com/c/en/us/support/docs/wireless-mobility/wireless-lan-wlan/82068-omni-vs-direct.html  1

 Jitter is most likely causing the issue of intermittent one-way audio and dropped conversations for the company that uses VoIP telephones. Jitter is a variation in delay of packets arriving at the destination. It can cause choppy or distorted audio quality for VoIP applications, especially over WAN links that have limited bandwidth and high latency. The recommended jitter for VoIP is less than 10ms1. The company has recorded ping times that exceed 50ms, which indicates high jitter and latency on their network. References: https://www.voip-info.org/voip-jitter/  1

RG-6 is a type of coaxial cable that is commonly used by cable companies to provide Internet access from the demarcation point back to the central office. It has a thicker conductor and better shielding than RG-59, which is another type of coaxial cable. Multimode and Cat 5e are types of fiber optic and twisted pair cables respectively, which are not typically used by cable companies. Cat 6 and 100BASE-T are standards for twisted pair cables, not types of cabling.

A honeypot is a decoy system that is intentionally left vulnerable or exposed to attract attackers and divert them from the real targets. A honeypot can also be used to collect information about the attackers’ techniques and motives. A network administrator can implement a honeypot to analyze attacks directed toward the company’s network, as a honeypot can help identify the source, target, method, and impact of an attack, as well as provide recommendations for remediation. References: https://www.comptia.org/blog/what-is-a-honeypot

The output is most likely an example of an ARP poisoning attack. ARP poisoning, also known as ARP spoofing, is a type of attack that exploits the ARP protocol to associate a malicious device’s MAC address with a legitimate IP address on a local area network. This allows the attacker to intercept, modify, or redirect network traffic between two devices without their knowledge. The output shows that there are multiple entries for the same IP address (192.168.1.1) with different MAC addresses in the ARP cache of the device. This indicates that an attacker has sent fake ARP replies to trick the device into believing that its MAC address is associated with the IP address of another device (such as the default gateway). References: https://www.cisco.com/c/en/us/about/security-center/arp-spoofing.html

IaaS stands for Infrastructure as a Service, which is a cloud computing model that provides virtualized computing resources such as servers, storage, and networking over the Internet. IaaS can provide data storage, hardware options, and scalability to a third-party company that cannot afford new devices by allowing them to rent or lease the infrastructure they need from a cloud provider. The company can pay only for what they use and scale up or down as needed. References: https://www.comptia.org/blog/what-is-iaas

The technician would most likely train the employee on using site-to-site VPNs between the two city locations and client-to-site software on the employee’s laptop for all other remote access. A VPN (Virtual Private Network) is a technology that creates a secure and encrypted tunnel over a public network such as the Internet. It allows remote users or sites to access a private network as if they were directly connected to it. A site-to-site VPN connects two or more networks, such as branch offices or data centers, using a VPN gateway device at each site. A client-to-site VPN connects individual users, such as mobile workers or telecommuters, using a VPN client software on their devices. In this scenario, the employee needs to access the network from different locations, such as home, travel, or another city. Therefore, the technician would train the employee on how to use site-to-site VPNs to connect to the network from another city location that shares services, and how to use client-to-site software to connect to the network from home or travel locations. References: https://www.cisco.com/c/en/us/support/docs/security-vpn/ipsec-negotiation-ike-protocols/14106-how-vpn-works.html

The firewall administrator is implementing a PAT (Port Address Translation) rule that directs HTTP traffic to an internal server listening on a non-standard socket. PAT is a type of NAT (Network Address Translation) that allows multiple devices to share a single public IP address by using different port numbers. PAT can also be used to redirect traffic from one port to another port on the same or different IP address. This can be useful for security or load balancing purposes. For example, a firewall administrator can configure a PAT rule that redirects HTTP traffic (port 80) from the public IP address of the firewall to an internal server that listens on a non-standard port (such as 8080) on its private IP address. References: https://www.cisco.com/c/en/us/support/docs/ip/network-address-translation-nat/13772-12.html

Time to live (TTL) is a value that indicates how long a DNS record can be cached by authoritative NSs (name servers) or other DNS servers before it expires and needs to be updated. A lower TTL value would expedite MX record updates to authoritative NSs, as they would refresh the record more frequently. UDP forwarding is not a DNS term, but a technique of sending UDP packets from one host to another. DNS caching is the process of storing DNS records locally for faster resolution, which does not expedite MX record updates. Recursive lookup is a type of DNS query where a DNS server queries other DNS servers on behalf of a client until it finds the answer, which does not expedite MX record updates.

SIEM stands for Security Information and Event Management, which is a tool that collects, analyzes, and correlates data from various network devices and sources to provide alerts and reports on security incidents and events. A network technician can use SIEM to correlate security events to analyze a suspected intrusion, as SIEM can help identify the source, target, method, and impact of an attack, as well as provide recommendations for remediation. References: https://www.comptia.org/blog/what-is-siem

 Using an out-of-band access method is the best way to prevent unauthorized access to the legacy switches that do not support cryptographic functions. Out-of-band access is a method of accessing a network device through a dedicated channel that is separate from the main network traffic. Out-of-band access can use physical connections such as serial console ports or dial-up modems, or logical connections such as VPNs or firewalls. Out-of-band access provides more security and reliability than in-band access, which uses the same network as the data traffic and may be vulnerable to attacks or failures. References: https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/fundamentals/configuration/15mt/fundamentals-15-mt-book/cf-out-band-mgmt.html

Change management documentation is a record of the changes that have been made to a system or process, including the reason, date, time, and impact of each change. A technician can reference this documentation to find what solution was implemented to resolve a previously encountered issue, as well as any potential side effects or dependencies of the change. References: https://www.comptia.org/blog/what-is-change-management

Clustering is a technique that involves grouping multiple servers or instances together to provide high availability and fault tolerance for a database. Clustering can help improve the availability of a SQL database by allowing automatic failover and load balancing between the cluster nodes. If one node fails or becomes overloaded, another node can take over the database operations without disrupting the service. References: https://www.educba.com/sql-cluster/

show interface is a command-line tool that displays information about the status, configuration, and statistics of an interface on a network device. A technician can use show interface to determine where the incident is occurring in a network by checking the uplink status, speed, duplex mode, errors, collisions, and other parameters of each interface. References: https://www.comptia.org/blog/what-is-show-interface

Load balancing is a technology that allows traffic to be sent through two different ISPs to increase performance. Load balancing is a process of distributing network traffic across multiple servers or links to optimize resource utilization, throughput, latency, and reliability. Load balancing can be implemented at different layers of the OSI model, such as layer 4 (transport) or layer 7 (application). Load balancing can also be used for outbound traffic by using multiple ISPs and routing protocols such as BGP (Border Gateway Protocol) to select the best path for each packet. References: https://www.cisco.com/c/en/us/products/collateral/ios-nx-os-software/border-gateway-protocol-bgp/prod_white_paper0900aecd806c4eeb.html

An omnidirectional antenna was used instead of a unidirectional antenna, which is most likely the cause of the wireless network issues. An omnidirectional antenna provides wireless coverage in all directions from the antenna, which can cause signal overlap with adjacent offices and interference with other wireless networks. A unidirectional antenna, on the other hand, provides wireless coverage in a specific direction from the antenna, which can reduce signal overlap and interference and increase signal range and quality. A unidirectional antenna would be more suitable for a warehouse environment where users are located on one side of the building1. References: https://www.cisco.com/c/en/us/support/docs/wireless-mobility/wireless-lan-wlan/82068-omni-vs-direct.html  1

If the link LEDs on the workstation and modem do not light up when connecting to a workstation, it could indicate a problem with the cable connecting them. The cable could be damaged, defective, or incompatible with the devices. A technician should replace the cable with a known good one and check if the link LEDs light up. If not, the problem could be with the network interface cards (NICs) on the workstation or modem. References: https://www.comptia.org/blog/what-is-link-light

Giants are packets that exceed the configured MTU (Maximum Transmission Unit) of a switchport or interface, which causes them to be dropped or fragmented by the switch or router. The MTU is the maximum size of a packet that can be transmitted without fragmentation on a given medium or protocol. Giants can indicate misconfiguration or mismatch of MTU values between devices or interfaces on a network, which can cause performance issues or errors. CRC errors are errors that occur when the cyclic redundancy check (CRC) value of a packet does not match the calculated CRC value at the destination, which indicates corruption or alteration of data during transmission due to noise, interference, faulty cabling, etc., but not necessarily exceeding MTU values. Runts are packets that are smaller than the minimum size allowed by the medium or protocol, which causes them to be dropped or ignored by the switch or router. Flooding is a technique where a switch sends packets to all ports except the source port when it does not have an entry for the destination MAC address in its MAC address table, which can cause congestion or broadcast storms on a network.

A virtual switch is a software-based switch that connects virtual machines on a hypervisor. A virtual switch can create and manage VLANs, which are logical segments of a network that isolate traffic between different groups of devices. A customer can use virtual switches to segregate the traffic between guests on a hypervisor by creating a separate VLAN for each guest and assigning it to a virtual switch port. References: https://www.comptia.org/blog/what-is-a-virtual-switch

A heat map would most likely be created as a result of the site survey. A heat map is a graphical representation of the wireless signal strength and coverage in a given area. It can show the location of APs, antennas, walls, obstacles, interference sources, and dead zones. It can help with planning, optimizing, and troubleshooting wireless networks. References: https://www.netspotapp.com/what-is-a-wifi-heatmap.html

A honeypot is a decoy system that is intentionally left vulnerable or exposed to attract attackers and divert them from the real targets. A honeypot can also be used to collect information about the attackers’ techniques and motives. In the scenario, the SaaS provider has left an unpatched VM available via a public DMZ port, which could be a honeypot technique to lure attackers and monitor their activities. References: https://www.comptia.org/blog/what-is-a-honeypot

SIEM stands for Security Information and Event Management, which is a tool that collects, analyzes, and correlates data from various network devices and sources to provide alerts and reports on security incidents and events. A report from the SIEM tool can provide a comprehensive overview of the network alerts from the past week to the executive staff, highlighting any potential threats, vulnerabilities, or anomalies. References: https://www.comptia.org/blog/what-is-siem

A hot site is the disaster recovery solution that the corporation should implement for its critical system that would cause unrecoverable damage to the brand if it was taken offline. A hot site is a fully operational backup site that can take over the primary site’s functions in case of a disaster or disruption. A hot site has all the necessary hardware, software, data, network connections, and personnel to resume normal operations with minimal downtime. A hot site is suitable for systems that require high availability and cannot afford any data loss or interruption. References: https://www.enterprisestorageforum.com/management/disaster-recovery-site/  1

The default credentials are the username and password that come with a device or service when it is first installed or configured. They are often easy to guess or find online, which makes them vulnerable to unauthorized access or attacks. The default credentials should be changed to something unique and strong as soon as possible to avoid this situation. If the default credentials were not changed, someone could have accessed the SOHO router and changed the WiFi settings without the employees’ knowledge. References: https://www.comptia.org/blog/network-security-basics-6-easy-ways-to-protect-your-network

A vSwitch (virtual switch) is a software-based switch that provides networking capability for VMs (virtual machines) at Layer 2 of the OSI model. It connects the VMs to each other or to external networks using virtual NICs (network interface cards). A VPN (virtual private network) is a technology that creates a secure tunnel over a public network for remote access or site-to-site connectivity. VRRP (Virtual Router Redundancy Protocol) is a protocol that provides high availability for routers by creating a virtual router with multiple physical routers. A VIP (virtual IP) is an IP address that can be shared by multiple servers or devices for load balancing or failover purposes.

EAP-TLS is the method that should be selected to meet the requirements for designing a new secure wireless network. EAP-TLS (Extensible Authentication Protocol - Transport Layer Security) is an authentication protocol that uses X.509 digital certificates for both clients and servers. It provides strong security and mutual authentication by using TLS encryption and public key cryptography. It does not use plaintext passwords or shared secrets that can be compromised or guessed. It is also an open standard that is vendor neutral and supported by most wireless devices1. References: https://www.securew2.com/blog/what-is-eap-tls  1

The time-to-live (TTL) field is the mechanism for ending loops at Layer 3, which is the network layer of the OSI model. The TTL field is an 8-bit field that indicates the maximum time or number of hops that an IP packet can travel before it is discarded. Every time an IP packet passes through a router, the router decrements the TTL value by one. If the TTL value reaches zero, the router drops the packet and sends an ICMP message back to the source, informing that the packet has expired. This way, the TTL field prevents an IP packet from looping endlessly in a network with routing errors or cycles123.

The other options are not mechanisms for ending loops at Layer 3. The checksum field is a 16-bit field that is used to verify the integrity of the IP header. The checksum field is calculated by adding all the 16-bit words in the header and taking the one’s complement of the result. If the checksum field does not match the calculated value, the IP packet is considered corrupted and discarded12. The type field, also known as the type of service (TOS) or differentiated services code point (DSCP) field, is an 8-bit field that is used to specify the quality of service (QoS) or priority of the IP packet. The type field can indicate how the packet should be handled in terms of delay, throughput, reliability, or cost12. The protocol field is an 8-bit field that is used to identify the transport layer protocol that is encapsulated in the IP packet. The protocol field can indicate whether the payload is a TCP segment, a UDP datagram, an ICMP message, or another protocol12.

SLAAC (Stateless Address Autoconfiguration) is a method for IPv6 devices to automatically configure their IP addresses based on the network prefix advertised by a router. The router sends periodic router advertisements (RAs) that contain the network prefix and other parameters for the devices to use. If the network gateway is not configured to send RAs, then SLAAC will not work. A DHCP server is not needed for SLAAC, as the devices generate their own addresses without relying on a server. Dual stack and anycast routing are not related to SLAAC.

Quality of service (QoS) is a mechanism that prioritizes network traffic based on different criteria, such as application type, source and destination address, port number, etc., and allocates bandwidth and resources accordingly. QoS would best improve performance for video conferencing, as it would ensure that video traffic gets higher priority and lower latency than other types of traffic on the network. Packet shaping is a technique that controls the rate or volume of network traffic by delaying or dropping packets that exceed certain thresholds or violate certain policies, which may not improve performance for video conferencing if it causes packet loss or jitter. Port mirroring is a technique that copies traffic from one port to another port on a switch for monitoring or analysis purposes, which does not improve performance for video conferencing at all. Load balancing is a technique that distributes network traffic across multiple servers or devices for improved availability and scalability, which does not

A router is a device that uses the destination IP address to forward packets between different networks. A bridge and a Layer 2 switch operate at the data link layer and use MAC addresses to forward frames within the same network. A repeater is a device that amplifies or regenerates signals at the physical layer.

RADIUS (Remote Authentication Dial-In User Service) is a protocol that should be used by the organization to allow for authentication, authorization, and auditing of network services. RADIUS is an AAA (Authentication, Authorization, and Accounting) protocol that manages network access by verifying user credentials, granting access permissions, and logging user activities. RADIUS uses a client-server model where a RADIUS client (such as a router, switch, or VPN server) sends user information to a RADIUS server (such as an authentication server) for verification and authorization. The RADIUS server can also send accounting information to another server for billing or reporting purposes. References: https://www.cisco.com/c/en/us/support/docs/security-vpn/remote-authentication-dial-user-service-radius/13838-10.html

A site-to-site VPN is a type of VPN that connects two or more remote offices securely over an untrustworthy network, such as the Internet. A site-to-site VPN allows each office to access network shares and resources at the other site, as if they were on the same local network. A site-to-site VPN encrypts and tunnels the traffic between the offices, ensuring privacy and integrity of the data. References: https://www.comptia.org/blog/what-is-a-site-to-site-vpn

 TCP is the protocol type that describes secure communication on port 443. TCP (Transmission Control Protocol) is a connection-oriented protocol that provides reliable and ordered delivery of data packets over an IP network. TCP uses port numbers to identify different applications or services on a device. Port 443 is the default port for HTTPS (Hypertext Transfer Protocol Secure), which is an extension of HTTP that uses SSL (Secure Sockets Layer) or TLS (Transport Layer Security) encryption to protect data in transit between a web server and a web browser. References: https://www.cisco.com/c/en/us/support/docs/ip/routing-information-protocol-rip/13788-3.html

Firmware is a type of software that controls the low-level functions of a hardware device, such as a router, switch, printer, or camera. Firmware updates are patches or upgrades that fix bugs, improve performance, add features, or address security vulnerabilities in firmware. Firmware updates are commonly used to address CVEs (Common Vulnerabilities and Exposures) on network equipment and operating systems, as CVEs are publicly known flaws that can be exploited by attackers. References: https://www.comptia.org/blog/what-is-firmware

A damaged cable is most likely the cause of the desktop not connecting to the network. A damaged cable can cause physical layer issues such as loss of signal, attenuation, interference, or crosstalk. These issues can prevent the desktop from establishing a link with the switch and result in the LED status light on the switchport being off. Other possible causes of physical layer issues are faulty connectors, ports, or transceivers. References: https://www.cisco.com/c/en/us/support/docs/lan-switching/ethernet/14119-37.html

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

10 additional network connections are needed to transition from a star to a full-mesh topology. A star topology is a network topology where each device is connected to a central device, such as a switch or a hub. A full-mesh topology is a network topology where each device is directly connected to every other device. The number of connections needed for a full-mesh topology can be calculated by the formula n(n-1)/2, where n is the number of devices. In this case, there are six devices (one core and five distribution switches), so the number of connections needed for a full-mesh topology is 6(6-1)/2 = 15. Since there are already five connections in the star topology (one from each distribution switch to the core switch), the number of additional connections needed is 15 - 5 = 10. References: https://www.cisco.com/c/en/us/support/docs/ip/routing-information-protocol-rip/13788-3.html

172.19.0.2 is a valid IP address configuration for the device that uses a static RFC1918 address for the network and allows for a connection over NAT (Network Address Translation). RFC1918 addresses are private IP addresses that are not routable on the public Internet and are used for internal networks. The RFC1918 address ranges are 10.0.0.0/8, 172.16.0.0/12, and 192.168.0.0/16. NAT is a technique that translates private IP addresses to public IP addresses when communicating with external networks, such as the Internet. FE80::1 is an IPv6 link-local address that is not a static RFC1918 address and does not allow for a connection over NAT. 100.64.0.1 is an IPv4 address that belongs to the shared address space range (100.64.0.0/10) that is used for carrier-grade NAT (CGN) between service providers and subscribers, which is not a static RFC1918 address and does not allow for a connection over NAT. 169.254.1.2 is an IPv4 link-local address that is automatically assigned by a device when it cannot obtain an IP address from a DHCP server or manual configuration, which is not a static RFC1918 address and does not allow for a connection over NAT. 224.0.0.12 is an IPv4 multicast address that is used for VRRP (Virtual Router Redundancy Protocol), which is not a static RFC1918 address and does not allow for a connection over NAT.

SNMP (Simple Network Management Protocol) is a protocol that allows network devices to communicate with a network management system (NMS) for monitoring and configuration purposes. SNMP traps are unsolicited messages sent by network devices to the NMS when certain events or conditions occur, such as errors, failures, or thresholds. Configuring SNMP traps on the network would best help the administrator determine the cause of jitter and high latency on a VoIP network, as they would provide real-time alerts and information about the network performance and status. Enabling RADIUS on the network is not relevant to troubleshooting VoIP issues, as RADIUS is a protocol that provides authentication, authorization, and accounting services for network access. Implementing LDAP on the network is also not relevant to troubleshooting VoIP issues, as LDAP is a protocol that provides directory services for storing and querying information about users, groups, devices, etc. Establishing NTP on the network is not directly related to troubleshooting VoIP issues, as NTP is a protocol that synchronizes the clocks of network devices.

 RJ11 is a type of connector that is commonly used for analog phone lines. RJ11 has four wires and six positions, but only two or four of them are used. A technician can crimp an RJ11 connector to a new phone line to install an analog desk phone for a new receptionist. References: https://www.comptia.org/blog/what-is-rj11

2.4GHz is the wireless frequency that would allow for the least signal attenuation when deploying a low-density wireless network with multiple types of building materials. Signal attenuation is the loss of signal strength or quality as it travels through a medium or over a distance. Signal attenuation can be affected by various factors such as distance, interference, reflection, refraction, diffraction, scattering, or absorption. Generally, lower frequencies have less signal attenuation than higher frequencies because they can penetrate obstacles better and travel farther. Therefore, 2.4GHz would have less signal attenuation than 5GHz, 850MHz, or 900MHz. References: https://www.cisco.com/c/en/us/support/docs/wireless-mobility/wireless-lan-wlan/82068-omni-vs-direct.html

Port tagging is a technique that involves adding a tag or identifier to the frames or packets that belong to a certain VLAN. A VLAN is a logical segment of a network that isolates traffic between different groups of devices. Port tagging allows devices on different physical ports or switches to communicate with each other as if they were on the same port or switch. Port tagging can help keep the design simple and efficient by reducing the number of physical ports and switches needed to segment departments into different networks. References: https://www.comptia.org/blog/what-is-port-tagging

A type 1 hypervisor is a system that is installed directly on a server’s hardware and abstracts the hardware from any guest machines. A hypervisor is a software layer that enables virtualization by creating and managing virtual machines (VMs) on a physical host. A type 1 hypervisor, also known as a bare-metal hypervisor or a native hypervisor, runs directly on the host’s hardware without requiring an underlying operating system (OS). It provides better performance and security than a type 2 hypervisor, which runs on top of an existing OS and relies on it for hardware access. References: https://www.vmware.com/topics/glossary/content/hypervisor

The default gateway is the setting that the user most likely misconfigured on the PC that caused it to be unable to access websites by both FQDN and IP. The default gateway is a device, usually a router or a firewall, that connects a local network to other networks such as the Internet. It acts as an intermediary between devices on different networks and forwards packets based on their destination IP addresses. If the default gateway is not configured correctly on a PC, it will not be able to communicate with devices outside its local network, such as web servers or DNS servers. References: https://www.cisco.com/c/en/us/support/docs/ip/routing-information-protocol-rip/16448-default-gateway.html

VPN (Virtual Private Network) is the most appropriate way to enable secure remote printing. VPN is a technology that creates a secure and encrypted tunnel over a public network such as the Internet. It allows remote users or sites to access a private network as if they were directly connected to it. VPN can be used for various purposes such as accessing corporate resources, bypassing geo-restrictions, or enhancing privacy and security. VPN can also be used for remote printing by allowing users to connect to a printer on the private network and send print jobs securely over the VPN tunnel. References: https://www.cisco.com/c/en/us/support/docs/security-vpn/ipsec-negotiation-ike-protocols/14106-how-vpn-works.html

The network administrator should confirm the patch’s MD5 hash prior to the upgrade to help ensure the upgrade process will be less likely to cause problems with the switches. MD5 (Message Digest 5) is a cryptographic hash function that produces a 128-bit hash value for any given input. It can be used to verify the integrity and authenticity of a file by comparing its hash value with a known or expected value. If the hash values match, it means that the file has not been corrupted or tampered with during transmission or storage. If the hash values do not match, it means that the file may be damaged or malicious and should not be used for the upgrade. References: https://www.cisco.com/c/en/us/support/docs/security-vpn/secure-shell-ssh/15292-scp.html

The switch processes the data by flooding it out of every port, except the one on which it came in. Flooding is a process where a switch sends a data frame to all ports except the source port when it does not have an entry for the destination MAC address in its MAC address table. Flooding allows the switch to learn the MAC addresses of the devices connected to its ports and update its MAC address table accordingly. Flooding also ensures that the data frame reaches its intended destination, even if the switch does not know its location. References: https://www.cisco.com/c/en/us/support/docs/lan-switching/spanning-tree-protocol/10556-16.html

The power level is a setting that determines how strong the wireless signal is from an access point (AP). If the power level is too high for an AP on the far side of a warehouse, it can cause interference and overlap with other APs on the same channel or frequency. This can result in handheld devices not connecting to the nearest APs, but connecting to the AP on the far side instead. A technician should adjust the power level of the AP on the far side to reduce interference and improve connectivity. References: https://www.comptia.org/blog/what-is-power-level

NDA stands for Non-Disclosure Agreement, which is a legal contract between two or more parties that outlines confidential material, knowledge, or information that the parties wish to share with one another for certain purposes, but wish to restrict access to by others. A network administrator may need to sign an NDA before sharing information about a new project with different vendors, as the project may involve sensitive or proprietary data that the company wants to protect from competitors or unauthorized use. References: https://www.adobe.com/sign/esignature-resources/sign-nda.html

Syslog is a protocol that provides a standard way for network devices and applications to send event messages to a logging server or a security appliance. Syslog messages can contain information about security incidents, errors, warnings, system status, configuration changes, and other events. A security appliance that is correlating network events from multiple devices can rely on Syslog to receive event messages from different sources and formats. References: https://www.comptia.org/blog/what-is-syslog