CompTIA N10-008 Dumps

EIGRP stands for Enhanced Interior Gateway Routing Protocol, which is a hybrid routing protocol that uses a successor and a feasible successor to determine the best route to a destination. A successor is the next-hop router that has the lowest cost (or metric) to reach the destination, and a feasible successor is a backup router that has a cost that is less than the cost of the successor. EIGRP uses the successor and the feasible successor to achieve fast convergence and load balancing. EIGRP also uses a Diffusing Update Algorithm (DUAL) to maintain the routing table and avoid routing loops. IS-IS, OSPF, and BGP are other routing protocols that do not use a successor and a feasible successor, but rather use different algorithms and criteria to select the best route.

References

• 1: EIGRP – N10-008 CompTIA Network+ : 2.1
• 2: CompTIA Network+ N10-008 Certification Study Guide, page 150-151
• 3: CompTIA Network+ N10-008 Exam Subnetting Quiz, question 20
• 4: CompTIA Network+ N10-008 Certification Practice Test, question 9

SLAAC (Stateless Address Autoconfiguration) is a method used by devices in an IPv6 network to configure their own IP addresses automatically using the link-local address and the network prefix that are advertised by routers. An error stating that there is an identical IP address already in use could occur if two devices on the network have duplicate MAC addresses. Since IPv6 addresses generated by SLAAC include the MAC address in the EUI-64 format, duplicate MAC addresses would result in identical IPv6 addresses. Options such as rogue DHCP server, incorrect router advertisement, and wrong VLAN assignment do not typically result in duplicate IP address conflicts under SLAAC since the address configuration is primarily derived from the MAC address​​.

• The question asks about the type of connection that would need to be set up to provide access from the internal network to an external network so multiple satellite offices can communicate securely using various ports and protocols.
• A connection is a logical or physical link between two or more devices or networks that allows data transmission and exchange.
• There are different types of connections that can be used for different purposes and scenarios, such as:
• In this scenario, the best type of connection to use is a site-to-site VPN, because it can provide the following benefits:
• Therefore, the answer is D, a site-to-site VPN, as it can provide access from the internal network to an external network so multiple satellite offices can communicate securely using various ports and protocols.

References:

• CompTIA Network+ N10-008 Study Guide, Chapter 4: Network Security, Section 4.2: Secure Network Design, Pages 204-207
• Professor Messer’s CompTIA N10-008 Network+ Course, Video 4.2: Secure Network Design, Part 2
• Network + N10-008 practice exam, Question 267, Answer D, Explanation

The attack which, if successful, would provide a malicious user who is connected to an isolated guest network access to the corporate network is VLAN hopping. VLAN hopping is an attack technique which involves tricking a switch into sending traffic from one VLAN to another. This is done by sending specially crafted packets, which force the switch to send traffic from one VLAN to another, thus allowing the malicious user to gain access to the corporate network.

VLAN hopping is an attack technique which involves tricking a switch into sending traffic from one VLAN to another. This is done by sending specially crafted packets, which force the switch to send traffic from one VLAN to another, thus allowing the malicious user to gain access to the corporate network. According to the CompTIA Network+ N10-008 Exam Guide  VLAN hopping is a type of attack that is used to gain access to network resources that are not meant to be accessible by a user on a guest network.

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?]

The switchport is shut down, which means it is administratively disabled and cannot forward traffic. The image shows that the switchport status is “down” and the protocol status is “down”, indicating that there is no physical or logical connection. The cable is plugged in, as shown by the “connected” message under the interface name. The loopback is not set, as shown by the “loopback not set” message under the encapsulation type. The bandwidth configuration is correct, as shown by the “BW 10000 Kbit/sec” message under the MTU size. References: [CompTIA Network+ Certification Exam Objectives], Domain 3.0 Infrastructure, Objective 3.1: Given a scenario, use appropriate networking tools, Subobjective: Command line tools (ping, netstat, tracert, etc.)

Port 25, by default, should be reserved for SMTP traffic to allow for a new cloud-based email server. SMTP stands for Simple Mail Transfer Protocol, which is a network protocol that enables email communication between mail servers and clients. SMTP uses port 25 as its default port for sending and receiving email messages over TCP/IP networks. A cloud-based email server is an email server that is hosted on a cloud service provider’s infrastructure, rather than on-premise or in-house. A cloud-based email server can offer advantages such as scalability, reliability, security, and cost-effectiveness. To allow for a new cloud-based email server, a firewall should be configured to open port 25 for SMTP traffic. References: [CompTIA Network+ Certification Exam Objectives], What Is SMTP? | Mailtrap Blog, Cloud Email Server: What Is It & How Does It Work? | Zoho Mail

DHCP scope exhaustion is the situation when a DHCP server runs out of available IP addresses to assign to clients. DHCP stands for Dynamic Host Configuration Protocol, which is a network protocol that automatically assigns IP addresses and other configuration parameters to clients on a network. A DHCP scope is a range of IP addresses that a DHCP server can distribute to clients. If the DHCP scope is exhausted, new clients will not be able to obtain an IP address and connect to the network. This can explain why the smart TV was not able to connect to the branch Wi-Fi on the first day, and why the bank laptop lost network access on the next day when the TV was connected. The technician should either increase the size of the DHCP scope or reduce the lease time of the IP addresses to avoid DHCP scope exhaustion. References: [CompTIA Network+ Certification Exam Objectives], DHCP Scope Exhaustion - What Is It? How Do You Fix It?

 A split tunnel VPN solution would allow secure, remote access for sales staff to the CRM application without impacting videoconferencing traffic. A VPN stands for virtual private network, which is a secure connection between two or more devices over a public network, such as the internet. A VPN encrypts and authenticates the data, ensuring its confidentiality and integrity. A split tunnel VPN is a type of VPN that allows some traffic to go through the VPN tunnel, while other traffic goes directly to the internet. This can improve performance and bandwidth utilization by reducing unnecessary encryption and routing overhead. By using a split tunnel VPN, sales staff can access the CRM application that connects to a database server in the corporate data center through the VPN tunnel, while using online videoconferencing services through their local internet connection. References: [CompTIA Network+ Certification Exam Objectives], What Is Split Tunneling? | NordVPN

• The end user can access local network shares and intranet pages, which means that the IP address and the subnet mask are configured correctly and the network interface is working properly.
• However, the end user is unable to access the internet or remote resources, which means that there is a problem with the name resolution or the routing of the traffic.
• The gateway address is responsible for routing the traffic to the destination network, which could be on the internet or another subnet. If the gateway address is incorrect, the end user would not be able to reach any network outside the local subnet.
• The DNS servers are responsible for resolving the domain names to the IP addresses, which are needed to communicate with the internet or remote resources. If the DNS servers are incorrect, the end user would not be able to resolve the names of the websites or servers they want to access.
• Therefore, the most likely cause of the connectivity issue is that the DNS servers need to be reconfigured with the correct addresses. References:
• CompTIA Network+ N10-008 Study Guide, Chapter 2: Network Protocols and Services, Section 2.2: TCP/IP Suite, p. 76-77
• Network+ N10-008 Practice Test, Question 359
• CompTIA Network+ (N10-008) Performance-based Questions (PBQs), Part 1, 1:36

Notifications are the lowest logging level and will provide the desired information regarding switch port up/down activity. According to the CompTIA Network+ Study Manual, notifications "are used for logging normal activities, such as port up/down events, link changes, and link flaps."

To see the configuration of a specific port on a switch, the network technician should use the "show interface" command. This command provides detailed information about the interface, including the current configuration, status, and statistics for the interface.

This subnet mask will allow you to have six usable IP addresses in each subnet, with a minimum of wasted addresses. You can use the following formula to calculate the number of subnets and the subnet ID for each subnet:

Number of subnets = 2^network bits Subnet ID = (subnet number - 1) x number of host addresses + network address

The network bits are the number of 1s in the binary representation of the subnet mask, and the network address is the first address in the range. For example, if your range is 192.168.1.0/27, then the network bits are 27, the network address is 192.168.1.0, and the number of host addresses is 30. Therefore, the number of subnets is 2^27, and the subnet ID for the first subnet is (1 - 1) x 30 + 192.168.1.0 = 192.168.1.0. The subnet ID for the second subnet is (2 - 1) x 30 + 192.168.1.0 = 192.168.1.32, and so on.

References

• Subnet masks are covered in Objective 1.4 of the CompTIA Network+ N10-008 certification exam1.
• Subnet masks can be calculated based on binary and CIDR-block notations2.
• Subnet masks can be used to determine the number of host bits and host addresses3.

1: CompTIA Network+ Certification Exam Objectives, page 4 2: IPv4 Subnet Masks – N10-008 CompTIA Network+ : 1.41 3: Calculating IPv4 Subnets and Hosts – N10-008 CompTIA Network+ : 1.44

Change management is the process of planning, implementing, and documenting changes to the network infrastructure, software, hardware, or configuration. It involves the following steps:

• Requesting a change: A change request is a formal document that describes the proposed change, the reason for it, the expected benefits, the potential risks, and the estimated costs and resources.
• Reviewing and approving a change: A change review board (CRB) or a change advisory board (CAB) is a group of stakeholders who evaluate the change request and decide whether to approve, reject, or modify it. The CRB or CAB may also prioritize the change request based on its urgency, impact, and feasibility.
• Scheduling and implementing a change: A change schedule is a calendar that shows when the approved changes will be executed. A change window is a specific time slot allocated for performing the change, usually during off-peak hours or maintenance periods. A change rollback plan is a contingency plan that outlines how to restore the network to its previous state in case of failure or unexpected results.
• Testing and validating a change: A change test plan is a set of procedures and criteria that verify the functionality, performance, and security of the network after the change. A change validation plan is a set of metrics and feedback mechanisms that measure the effectiveness and satisfaction of the change.
• Documenting and communicating a change: A change log is a record of all the changes made to the network, including the date, time, description, status, and outcome of each change. A change notification is a message that informs the affected users, customers, and vendors about the change, its purpose, its impact, and its duration.

Change management is used to enforce and schedule critical updates with supervisory approval and include backup plans in case of failure because it ensures that the updates are aligned with the business objectives, comply with the security policies, minimize the disruption and downtime, and improve the network performance and reliability.

References:

• [CompTIA Network+ N10-008 Certification Study Guide], Chapter 5: Network Operations, Section 5.2: Change Management, pp. 269-271
• [Professor Messer’s CompTIA N10-008 Network+ Course Notes], Section 5.2: Change Management, p. 68
• [Professor Messer’s CompTIA N10-008 Network+ Training Course], Video 5.2: Change Management, 12:31 minutes

"Use private VLANs: Also known as port isolation, creating a private VLAN is a method of restricting switch ports (now called private ports) so that they can communicate only with a particular uplink. The private VLAN usually has numerous private ports and only one uplink, which is usually connected to a router, or firewall."

TACACS+ is used to authenticate users and authorize access to network resources. This protocol provides greater network security by encrypting the authentication credentials and reducing the risk of unauthorized access. According to the CompTIA Network+ Study Manual, “TACACS+ is an authentication protocol used to centralize authentication and authorization for network devices. It is a more secure alternative to Telnet for handling logins and for granting privileges to users.”

The DHCP client sends broadcast request packets to the network; the DHCP servers respond with broadcast packets that offer IP parameters, such as an IP address for the client. After the client chooses the IP parameters, communication between the client and server is by unicast packets.

"When a DHCP client boots up, it automatically sends out a DHCP Discover UDP datagram to the broadcast address, 255.255.255.255. This DHCP Discover message asks “Are there any DHCP servers out there?” The client can’t send unicast traffic yet, as it doesn’t have a valid IP address that can be used."

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

A layer 2 switch is a device that forwards traffic based on MAC addresses within a single network segment or VLAN. A layer 2 switch is best suited for use at the access layer in a three-tier architecture system. The access layer is the layer that connects end devices such as computers, printers, and phones to the network. A layer 2 switch can provide fast and efficient switching for end devices without adding complexity or overhead to the network. References: (page 139)

• Seamless roaming is the ability of a wireless device to move from one access point (AP) to another without losing connectivity or experiencing delays1.
• When multiple SSIDs are deployed in a wireless network, each SSID acts as a separate network with its own security settings, encryption methods, and authentication protocols2.
• This means that a wireless device has to disconnect from one SSID and reconnect to another SSID when moving between different APs, which can cause interruptions and performance issues2.
• By consolidating multiple SSIDs into one unique SSID, the technician can simplify the network management and improve the user experience2.
• The wireless device can then associate with any AP that broadcasts the same SSID, and switch between them without re-authenticating or re-negotiating the security parameters2.
• This enables seamless roaming and reduces the overhead and complexity of the wireless network2. References:
• 1: CompTIA Network+ N10-008 Exam Cram, 6th Edition, Chapter 6: Wireless Network Technologies, p. 212
• 2: CompTIA Network+ N10-008 Cert Guide, 1st Edition, Chapter 9: Wireless Network Design and Troubleshooting, pp. 367-368

Given that hardware upgrades are not an option, the best configuration to provide a solution for increased bandwidth on wireless laptops is Channel bonding. Here’s why:

• Increasing RSSi: RSSi (Received Signal Strength Indicator) is related to signal strength but does not directly address bandwidth limitations.
• MIMO (Multiple Input, Multiple Output): While MIMO improves throughput, it requires compatible hardware on both ends (access points and client devices). Since hardware upgrades are not allowed, MIMO is not a viable solution.
• Channel bonding: This technique combines multiple adjacent channels to increase overall bandwidth. By using multiple channels simultaneously, the available bandwidth can be expanded without changing the hardware.
• Reconfiguring SSID: Changing the SSID (Service Set Identifier) won’t directly impact bandwidth; it only affects network identification.

Therefore, the correct answer is C. Channel bonding2.

The ARP table is a database that is used by a device to map MAC addresses to their corresponding IP addresses. When a device sends a packet to another device on the same network, it uses the MAC address of the destination device to deliver the packet. The ARP table allows the device to determine the IP address of the destination device based on its MAC address.

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

• An optical time-domain reflectometer (OTDR) is a device that can measure the characteristics of an optical fiber, such as its length, attenuation, and splice points12.
• An OTDR works by sending a pulse of light into one end of the fiber and measuring the amount of light that is reflected back at different intervals12.
• By analyzing the reflected light, an OTDR can determine the distance to any faults or breaks in the fiber, as well as the overall quality of the fiber12.
• An OTDR can also provide a graphical representation of the fiber, called a trace, that shows the attenuation and reflection along the fiber12.
• Using an OTDR can reduce repair time because it can quickly and accurately locate the fault point in the fiber, without requiring access to both ends of the fiber12.
• The other options are not suitable for testing fiber optic cables:

References:

• 1: Optical Fiber - N10-008 CompTIA Network+ : 1.3
• 2: CompTIA Network+ N10-008 Full Course for Beginners - Fiber Optic Cabling and Connectors
• 3: Wire Crimpers and Testers - N10-008 CompTIA Network+ : 1.3
• 4: Multimeter - N10-008 CompTIA Network+ : 1.3
• 5: Spectrum Analyzer - N10-008 CompTIA Network+ : 1.3

• The question describes a scenario where a network event is causing all communication to stop, and the network administrator can only access the switch using the serial console port, not SSH.
• This suggests that the problem is related to the network layer or below, as SSH operates at the application layer and requires network connectivity to function.
• The port statistics show a huge discrepancy between the total receive and transmit rates, as well as the unicast and broadcast/multicast packets per second. This indicates that there is a lot of traffic being generated and forwarded within the network, but not reaching the intended destinations.
• The most likely cause of this excessive traffic is a switch loop, which occurs when there are multiple paths between switches that create a circular flow of data. Switch loops can cause broadcast storms, MAC address table instability, and network congestion, leading to network outages.
• To verify this, the network administrator should use a tool such as Spanning Tree Protocol (STP), which is designed to prevent and detect switch loops by blocking redundant links and electing a root bridge. STP can also provide information about the topology and status of the network, such as the root port, designated port, and blocked port for each switch. References:
• CompTIA Network+ N10-008 Study Guide, Chapter 2, Section 2.3, Switching Technologies, page 741
• Professor Messer’s CompTIA N10-008 Network+ Course Notes, Section 2.3, Switching Technologies, page 132
• Professor Messer’s CompTIA N10-008 Network+ Training Course, Video 2.3 - Switching Technologies, 12:00 - 14:003

To determine if a client's network cable issues may be causing intermittent connectivity, the help desk technician can run the show interface command on the switch. This command allows the technician to view the status and statistics of the various interfaces on the switch, including the physical link status and the number of transmitted and received packets. If the interface is experiencing a large number of errors or dropped packets, this could indicate a problem with the network cable or with the connection between the client's device and the switch.

"Cisco routers and switches have a show interfaces IOS command that provides interface statistics/status information, including link state (up/down), speed/duplex, send/receive traffic, cyclic redundancy checks (CRCs), and protocol packet and byte counts."

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)?

Network security groups are cloud components that can filter inbound and outbound traffic between cloud resources based on rules and priorities. Network security groups can be applied to virtual machines, subnets, or network interfaces to control the network access and security. Network security groups can allow or deny traffic based on the source, destination, port, and protocol of the packets. Network security groups are different from NAT gateways, service endpoints, and virtual private clouds, which are other cloud components that have different functions and purposes.

References

• 1: Network Security Groups – N10-008 CompTIA Network+ : 3.2
• 2: CompTIA Network+ N10-008 Certification Study Guide, page 329-330
• 3: CompTIA Network+ N10-008 Exam Subnetting Quiz, question 17
• 4: CompTIA Network+ N10-008 Certification Practice Test, question 10

• A site survey is a process of testing and documenting the wireless coverage, performance, and interference in a specific area12.
• A site survey can help identify the optimal locations, orientations, and configurations for the wireless access points (APs), antennas, and other devices12.
• A site survey can also help troubleshoot issues related to latency and drops in coverage, by measuring the signal strength, noise level, channel utilization, and other factors that affect the wireless network quality12.
• A site survey is usually performed before deploying a wireless network, but it can also be done after the deployment to verify the network performance or to diagnose any problems12.
• A site survey is the FIRST step to troubleshoot the issues in this scenario, because it can provide a comprehensive overview of the wireless network status and reveal any potential causes of the issues12.
• The other options are not the first step to troubleshoot the issues, because they are either more specific or less effective than a site survey:

References:

• 1: Wireless Troubleshooting – N10-008 CompTIA Network+ : 5.4
• 2: CompTIA Network+ N10-008 Full Course for Beginners - Wireless Troubleshooting
• 3: Channel Utilization - N10-008 CompTIA Network+ : 3.3
• 4: Cable Testing - N10-008 CompTIA Network+ : 1.3

The default gateway is the IP address of the router that connects the PC to other networks. The default gateway should be on the same subnet as the PC’s IPv4 address. However, in this case, the default gateway is 192.168.9.1, which is on a different subnet than the PC’s IPv4 address of 192.168.8.15. Therefore, the default gateway configuration on the PC is incorrect and prevents the PC from reaching the file server on another subnet.

The most accurate NTP (Network Time Protocol) time source that can be accessed across a network connection is the Stratum 1 device. Here’s why:

• Stratum 0 device: These are reference clocks, such as atomic clocks or GPS receivers, which directly measure time. They are not accessible over the network.
• Stratum 1 device: These are servers that synchronize their time with Stratum 0 devices. They are highly accurate and can be accessed over the network.
• Stratum 7 device: This is not a standard stratum level in NTP. The valid stratum levels are 0 to 16.
• Stratum 16 device: This is a reserved value and not used in practice.

Therefore, the correct answer is B. Stratum 1 device1.

A Common Vulnerabilities and Exposures (CVE) is a publicly available database of known security vulnerabilities and exposures that affect various software and hardware products. A CVE entry provides a standardized identifier, a brief description, and references to related sources of information for each vulnerability or exposure. A network administrator can reference the CVE database to check if any of the systems on the network are affected by a known vulnerability, and if so, what are the potential impacts and mitigations.

A Service Level Agreement (SLA) is a contract between a service provider and a customer that defines the expected level and quality of service, such as availability, performance, and security. An SLA does not provide information on specific vulnerabilities or exposures affecting the systems or services.

A Patch Management Policy is a set of rules and procedures that govern how patches are applied to systems and software to fix bugs, improve functionality, or address security issues. A patch management policy can help prevent or reduce the risk of vulnerabilities or exposures, but it does not provide information on specific vulnerabilities or exposures affecting the systems or software.

A Non-Disclosure Agreement (NDA) is a legal contract between two or more parties that prohibits the disclosure of confidential or proprietary information to unauthorized parties. An NDA does not provide information on specific vulnerabilities or exposures affecting the systems or information.

A Site Survey Report is a document that summarizes the results of a physical inspection and assessment of a network site, such as the layout, infrastructure, equipment, and environmental conditions. A site survey report can help identify and resolve potential network issues, such as interference, signal strength, or coverage, but it does not provide information on specific vulnerabilities or exposures affecting the network devices or software.

References

What is CVE?

What is a Service Level Agreement (SLA)?

Guide to Enterprise Patch Management Planning

NDA, MSA, SOW and SLA. Confidentiality agreements when you outsource QA

Site Survey Report

Changing the default password is a hardening technique that best mitigates the use of publicly available information, such as vendor documentation, online forums, or hacking tools, that may reveal the default credentials of a commercial switch. By changing the default password to a strong and unique one, the network technician can prevent unauthorized access to the switch configuration and management.

References:

• Network Hardening - N10-008 CompTIA Network+ : 4.3 - YouTube1
• CompTIA Network+ Certification Exam Objectives, page 151

An A record, also known as an address record, is a type of DNS record that maps a hostname to an IPv4 address. An A record is used to resolve a domain name to an IP address, so that clients can connect to the server or service by using the domain name instead of the IP address. For example, an A record can map to 192.0.2.1.

An A record is the most common type of DNS record for cloud DNS, as it allows the company to use a custom domain name for their cloud services, such as web hosting, email, or storage. An A record can also be used to create subdomains, such as blog.example.com or mail.example.com, that point to different IP addresses or servers.

The other options are not correct because they are not the best type of DNS record for cloud DNS. They are:

• MX. MX stands for mail exchange, and it is a type of DNS record that specifies the mail servers that are responsible for receiving and delivering email messages for a domain name. MX records are used for email services, but they are not sufficient for cloud DNS, as they do not map a hostname to an IP address.
• CNAME. CNAME stands for canonical name, and it is a type of DNS record that specifies an alias name for another domain name. CNAME records are used to create multiple names for the same IP address or server, such as www.example.com and example.com. CNAME records are useful for cloud DNS, but they are not the best type, as they depend on another A record to resolve the IP address.
• NS. NS stands for name server, and it is a type of DNS record that delegates a DNS zone to an authoritative server. NS records are used to specify which DNS servers are responsible for answering queries for a domain name or a subdomain. NS records are essential for cloud DNS, but they are not the best type, as they do not map a hostname to an IP address.

References1: DNS records overview | Google Cloud2: Network+ (Plus) Certification | CompTIA IT Certifications3: ClouDNS: What is a DNS record?

• A basic service set (BSS) is a group of wireless devices that share the same service set identifier (SSID) and communicate with each other through a single access point (AP). A BSS is also known as an infrastructure mode network1.
• An extended service set (ESS) is a group of two or more BSSs that are connected by a distribution system (DS), such as a switch or a router. An ESS allows wireless devices to roam between different APs and maintain network connectivity. An ESS is also known as a wireless LAN (WLAN)2.
• An independent basic service set (IBSS) is a group of wireless devices that communicate with each other directly without using an AP or a DS. An IBSS is also known as an ad hoc network or a peer-to-peer network3.
• MU-MIMO (Multi-User Multiple-Input Multiple-Output) is a technology that allows an AP to transmit data to multiple wireless devices simultaneously using multiple antennas and spatial streams. MU-MIMO can improve the network efficiency and performance by reducing the waiting time and increasing the throughput4.
• The scenario described in the question is an example of an IBSS, as the two laptops are connected directly to each other using 802.11ac without an AP. Therefore, the correct answer is C.

References:

• 1: BSS
• 2: ESS
• 3: IBSS
• 4: MU-MIMO

This is the port number for HTTPS, which stands for Hypertext Transfer Protocol Secure. HTTPS is a secure version of HTTP, which is the protocol used to communicate between web browsers and web servers. HTTPS encrypts the data sent and received using SSL/TLS, which are cryptographic protocols that provide authentication, confidentiality, and integrity. HTTPS is commonly used for online transactions, such as banking and shopping, where security and privacy are important

A Service-level agreement (SLA) is a document that outlines the responsibilities of a cloud service provider and the customer. It typically includes the agreed-upon availability of the cloud service provider, the expected uptime for the service, and the cost of any downtime or other service interruptions. Consulting the SLA is the best way for the management team to determine the promised availability of the cloud provider. Reference: CompTIA Cloud+ Study Guide, 6th Edition, page 28.

• A vulnerability scan is a process of identifying and reporting the weaknesses or flaws in a system or network that could be exploited by attackers. A vulnerability scan is conducted frequently to maintain an updated list of a system’s weaknesses, as new vulnerabilities may emerge over time due to changes in the system configuration, software updates, or external factors. A vulnerability scan can help to prioritize the remediation efforts and improve the security posture of the system or network.
• A penetration test is a process of simulating a real-world attack on a system or network to evaluate its security and identify the potential impact of a breach. A penetration test is conducted periodically or after a major change in the system or network, as it is more intrusive and time-consuming than a vulnerability scan. A penetration test can help to validate the effectiveness of the security controls and measures in place and provide recommendations for improvement.
• A posture assessment is a process of evaluating the current security status of a system or network against a set of standards or best practices. A posture assessment is conducted periodically or as part of a compliance audit, as it is more comprehensive and holistic than a vulnerability scan or a penetration test. A posture assessment can help to identify the gaps or weaknesses in the security policies, procedures, and practices and provide guidance for improvement.
• A risk assessment is a process of analyzing the likelihood and impact of various threats and vulnerabilities on a system or network. A risk assessment is conducted periodically or as part of a risk management process, as it is more strategic and business-oriented than a vulnerability scan, a penetration test, or a posture assessment. A risk assessment can help to determine the acceptable level of risk and the appropriate mitigation strategies and resources.

References:

• CompTIA Network+ N10-008 Study Guide, Chapter 8: Network Security Concepts and Tools, Section 8.2: Security Assessment Tools, Page 3721
• Professor Messer’s CompTIA N10-008 Network+ Course Notes, Section 8.2: Security Assessment Tools, Page 462
• What is a Vulnerability Scan? | Definition and Examples3
• What is a Penetration Test? | Definition and Examples
• What is a Security Posture Assessment? | Definition and Examples
• [What is a Risk Assessment? | Definition and Examples]

ping -t is an option for the ping command in Windows that allows the user to send continuous ping requests to a target until stopped by pressing Ctrl-C. This can help the technician run a constant ping command while testing various possible reasons for the connectivity issue. ping -w is an option for the ping command in Windows that allows the user to specify a timeout value in milliseconds for each ping request. ping -i is an option for the ping command in Linux that allows the user to specify the time interval in seconds between each ping request. ping -s is an option for the ping command in Linux that allows the user to specify the size of the data payload in bytes for each ping request.

References: How to Use the Ping Command in Windows - Lifewire

• The command show interface is used to display information about the status, speed, duplex mode, and other parameters of the network interfaces on a device. It can also show the number of packets sent and received, the error rate, and the utilization rate of each interface.
• The command can help determine whether an LACP bundle is fully operational by showing the aggregated bandwidth, the load balancing method, the active and standby links, and the LACP protocol status of each interface in the bundle.
• LACP (Link Aggregation Control Protocol) is a protocol that allows multiple physical links to be combined into a logical link, or a bundle, to increase the bandwidth and provide redundancy. LACP is also known as IEEE 802.3ad or EtherChannel.
• The command show config is used to display the current configuration of the device, such as the hostname, the IP addresses, the routing protocols, the security settings, and the interface settings. It does not show the operational status of the interfaces or the LACP bundle.
• The command show route is used to display the routing table of the device, which contains the destination networks, the next-hop addresses, the interface names, and the metrics of the routes. It does not show the operational status of the interfaces or the LACP bundle.
• The command show arp is used to display the ARP (Address Resolution Protocol) cache of the device, which contains the mappings between the IP addresses and the MAC addresses of the devices on the local network. It does not show the operational status of the interfaces or the LACP bundle. References:
• CompTIA Network+ N10-008 Study Guide, Chapter 2: Network Devices and Technologies, Section 2.1: Explain the functions and purposes of various network devices, Page 77-78
• Professor Messer’s Network+ N10-008 Course Notes, Page 13
• Professor Messer’s Network+ N10-008 Video Training Course, Section 2.1: Network Devices, Video 2.1.6: Link Aggregation

A short circuit is a condition where two conductors in a circuit are connected unintentionally, creating a low resistance path for the current. This causes the voltage to drop and the current to increase, which can damage the circuit or cause a fire. A multimeter can measure the resistance or impedance of a circuit, and if it shows extremely low values, it indicates a short circuit.

• A botnet is a network of compromised devices that are remotely controlled by a malicious actor, usually for the purpose of launching distributed denial-of-service (DDoS) attacks, sending spam, stealing data, or performing other malicious activities1.
• A malware infection is a common way of compromising internet-connected devices and making them part of a botnet. Malware is any software that is designed to harm or exploit a device, a network, or a user. Malware can be delivered through various methods, such as phishing emails, malicious downloads, drive-by downloads, or removable media2. Malware can infect a device and allow a remote attacker to take control of it, monitor its activities, or use its resources3.
• The use of default credentials is another common way of compromising internet-connected devices and making them part of a botnet. Default credentials are the username and password combinations that are preconfigured by the manufacturer or vendor of a device, such as a router, a camera, or a printer. Default credentials are often easy to guess or find online, and many users do not change them after setting up their devices. This makes the devices vulnerable to unauthorized access and manipulation by attackers who can scan the internet for devices with default credentials and add them to their botnet .
• A deauthentication attack is a type of wireless attack that aims to disconnect a legitimate user from a wireless network by sending spoofed deauthentication frames to the user’s device or the access point (AP). A deauthentication attack can cause a denial of service, disrupt network communication, or facilitate other attacks, such as capturing the handshake during the reconnection process. However, a deauthentication attack does not compromise the device or make it part of a botnet.
• IP spoofing is a technique of forging the source IP address of a packet to make it appear as if it came from a different device or location. IP spoofing can be used to bypass security filters, hide the identity of the attacker, or launch reflection or amplification attacks. However, IP spoofing does not compromise the device or make it part of a botnet, unless it is combined with other methods, such as malware infection or exploitation of vulnerabilities.
• Firmware corruption is a condition where the firmware of a device, which is the software that controls its basic functions and operations, becomes damaged or altered due to various reasons, such as power surges, hardware failures, malicious attacks, or improper updates. Firmware corruption can cause the device to malfunction, lose data, or become inaccessible. However, firmware corruption does not compromise the device or make it part of a botnet, unless it is caused by a malicious attack that replaces the firmware with a malicious version.
• A dictionary attack is a type of brute-force attack that tries to guess the password of a user or a device by using a list of common or likely passwords, such as those found in a dictionary, a database, or a previous breach. A dictionary attack can be used to compromise a device and make it part of a botnet, but only if the device has a weak or predictable password. Therefore, a dictionary attack is not a direct way of compromising a device, but rather a means of exploiting the use of default or weak credentials.

References:

• 1: Botnet
• 2: Malware
• 3: How Malware Can Turn Your Device into a Botnet
• : [Default Credentials]
• : [How Default Credentials Can Lead to IoT Botnets]
• : [Deauthentication Attack]
• : [IP Spoofing]
• : [Firmware Corruption]
• : [Dictionary Attack]

A hot site is a backup site that is fully equipped and ready to take over the operations of the primary site in the event of a disaster. A hot site has real-time synchronization with the primary site and can provide zero data loss. A hot site is the most expensive and reliable option for disaster recovery.

References: Network+ Study Guide Objective 5.3: Explain common scanning, monitoring and patching processes and summarize their expected outputs.

802.11n is the best choice for setting up a wireless connection that utilizes MIMO on non-overlapping channels. 802.11n is a wireless standard that offers faster speeds and longer range than previous standards. 802.11n uses multiple-input multiple-output (MIMO) technology, which allows multiple antennas to transmit and receive multiple spatial streams of data simultaneously. MIMO can improve wireless performance, reliability, and capacity by exploiting multipath propagation and spatial diversity. 802.11n also uses non-overlapping channels in both the 2.4 GHz and 5 GHz frequency bands to avoid interference and increase bandwidth. Non-overlapping channels are channels that do not share any part of their frequency spectrum with other channels. References: [CompTIA Network+ Certification Exam Objectives], 802.11n - Wikipedia

SLAAC (Stateless Address Autoconfiguration) is a mechanism that enables each host on the network to auto-configure a unique IPv6 address without any device keeping track of which address is assigned to which node12. SLAAC uses link-local addresses and the interface’s MAC address or a random number to generate the host portion of the IPv6 address2. SLAAC also relies on Router Solicitation (RS) and Router Advertisement (RA) messages to obtain the network prefix and other information from a router12. Therefore, to change an entire subnet of SLAAC-configured workstation addresses, the network engineer needs to change the address prefix in a router and let the router advertise the new prefix with an ND (Neighbor Discovery) message. This way, the workstations will receive the new prefix and update their IPv6 addresses accordingly3.

References1 - IPv6 Stateless Address Auto-configuration (SLAAC) | NetworkAcademy.io2 - IPv6 SLAAC – Stateless Address Autoconfiguration - Study-CCNA3 - Mastering IPv6 SLAAC Concepts and Configuration - Cisco Press

A role-based access control (RBAC) policy is a security measure that assigns permissions and privileges to users based on their roles and responsibilities within an organization. RBAC helps to enforce the principle of least privilege, which states that users should only have the minimum level of access required to perform their tasks. RBAC also helps to prevent unauthorized access, modification, or misuse of sensitive data or resources by limiting the scope and impact of user actions.

A software patching policy, firewalls on the software development servers, and longer and more complex password requirements are all good security practices, but they do not directly address the issue of preventing the former software developer from modifying code. A software patching policy ensures that software is updated regularly to fix bugs and vulnerabilities, but it does not prevent a user from introducing new code changes. Firewalls on the software development servers protect the servers from external attacks, but they do not prevent a user from accessing the servers internally. Longer and more complex password requirements make it harder for attackers to guess or crack passwords, but they do not prevent a user from using their own valid credentials.

References

1: Role-Based Access Control (RBAC) - Definition and Examples

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

3: [What is the Principle of Least Privilege? - Definition from Techopedia]

A divide-and-conquer approach is a troubleshooting method that involves breaking a complex problem into smaller and more manageable parts, and then testing each part to isolate the cause of the problem. In this scenario, the technician is using a divide-and-conquer approach by pinging the default gateway and DNS server of the workstation, which are two possible sources of connectivity issues. By pinging these devices, the technician can determine if the problem is related to the local network or the external network.

Which of the following most likely requires the use of subinterfaces?

• A router with only one available LAN port
• A firewall performing deep packet inspection
• A hub utilizing jumbo frames
• A switch using Spanning Tree Protocol

Answer: A

Subinterfaces are logical divisions of a physical interface that allow a router to communicate with multiple networks using a single LAN port. Subinterfaces can have different IP addresses, VLANs, and routing protocols. They are useful for reducing the number of physical interfaces and cables needed, as well as improving network performance and security.

References:

• Subinterfaces - CompTIA Network+ N10-008 Domain 1.21 - YouTube1
• CompTIA Network+ Certification Exam Objectives, page 92

Which of the following is a characteristic of the application layer?

• It relies upon other layers for packet delivery.
• It checks independently for packet loss.
• It encrypts data in transit.
• It performs address translation.

Answer: A

The application layer is the highest layer of the OSI model, and it provides the interface between the user and the network. It does not handle the details of packet delivery, such as addressing, routing, error checking, or encryption. Those functions are performed by the lower layers of the OSI model. The application layer only focuses on the format, content, and presentation of the data.

References:

• Understanding the OSI Model – N10-008 CompTIA Network+ : 1.11
• CompTIA Network+ Certification Exam Objectives, page 92

Port security is a feature that can be configured on a switch interface to limit and identify the MAC addresses of workstations that are allowed to connect to that specific port. This can help ensure that only a specific workstation (or workstations) can connect to the interface. According to the CompTIA Network+ Study Manual, “Port security can be used to specify which MAC addresses are allowed to connect to a particular switch port. If a port security violation is detected, the switch can take a number of different actions, such as shutting down the port, sending an SNMP trap, or sending an email alert.”

BGP is a routing protocol that is used to exchange routing information between different autonomous systems (ASes) on the internet. An autonomous system is a network or group of networks that is under the same administrative control and uses a common routing protocol. By acquiring its own public IP prefixes and autonomous system number, a company can use BGP to advertise these prefixes to other ASes and establish its own internet connection. This would enable the company to have more control over its internet connection and potentially improve its connectivity.EIGRP (Enhanced Interior Gateway Routing Protocol) is a routing protocol used within a single autonomous system, so it would not be used to establish a connection to the internet. IPv6 is a version of the Internet Protocol (IP) used to identify devices on a network. It is not a routing protocol and would not be used to establish an internet connection.MPLS (Multi-Protocol Label Switching) is a networking technology that is used to route packets between different networks. It is not a routing protocol and would not be used to establish an internet connection.

• BGP stands for Border Gateway Protocol, and it is the standard protocol for exchanging routing information between different autonomous systems (AS) on the internet12. An AS is a network or a group of networks under a single administrative control, such as an ISP or a large enterprise12.
• BGP is an Exterior Gateway Protocol (EGP), which means it is used to communicate with routers outside the local network or AS12. BGP allows each AS to advertise its own routes and policies to other ASes, and to learn the best routes to reach any destination on the internet12.
• BGP is generally used by major ISPs for handling large-scale internet traffic because it is highly scalable, flexible, and reliable12. BGP can handle millions of routes and thousands of ASes, and it can support various routing policies and preferences12. BGP also has mechanisms to detect and avoid routing loops, and to recover from network failures12.
• The other options are not suitable for handling large-scale internet traffic across different ASes. RIP (Routing Information Protocol) and EIGRP (Enhanced Interior Gateway Routing Protocol) are both Distance Vector protocols, which means they use the number of hops as the metric to find the best route34. They are also Interior Gateway Protocols (IGP), which means they are used to communicate with routers within the same network or AS34. RIP and EIGRP are not scalable or flexible enough to handle the complexity and diversity of the internet34. OSPF (Open Shortest Path First) is a Link State protocol, which means it uses the speed and cost of the links as the metric to find the best route5. It is also an IGP, which means it is used to communicate with routers within the same network or AS5. OSPF is more scalable and flexible than RIP and EIGRP, but it still has limitations in handling large-scale internet traffic across different ASes5. References:
• 1: CompTIA Network+ N10-008 Certification Study Guide, Chapter 3: Routing, Section 3.4: BGP6
• 2: Professor Messer’s CompTIA N10-008 Network+ Course Notes, Page 18: BGP7
• 3: CompTIA Network+ N10-008 Certification Study Guide, Chapter 3: Routing, Section 3.2: RIP and EIGRP6
• 4: Professor Messer’s CompTIA N10-008 Network+ Course Notes, Page 16: RIP and EIGRP7
• 5: CompTIA Network+ N10-008 Certification Study Guide, Chapter 3: Routing, Section 3.3: OSPF6
• 6: CompTIA Network+ N10-008 Certification Study Guide2
• 7: Professor Messer’s CompTIA Network+ N10-008 Training Course5

Elasticity is the ability of a cloud service to automatically adjust the amount of resources allocated to meet the changing demand of the users. Elasticity enables a cloud service to scale up or down resources quickly and efficiently, without requiring manual intervention or planning. Elasticity is ideal for scenarios where the demand is unpredictable, dynamic, or seasonal, such as online gaming tournaments. By using elasticity, the online gaming company can ensure optimal performance and user experience during peak times, while also saving costs and avoiding overprovisioning during off-peak times.

The other options are not correct because they do not address the specific needs of the online gaming company. They are:

•Scalability is the ability of a cloud service to handle an increase or decrease in the demand of the users by adding or removing resources. Scalability is similar to elasticity, but it is more manual, planned, and predictive, while elasticity is automatic, prompt, and reactive. Scalability is suitable for scenarios where the demand is steady, predictable, or gradual, such as a growing business or a long-term project.

•Hybrid is a type of cloud model that combines two or more clouds, such as on-premises private, hosted private, or public, that can be centrally managed to enable interoperability for various use cases. Hybrid cloud can offer benefits such as flexibility, security, and cost-efficiency, but it does not directly address the need for dynamic resource allocation for the online gaming company.

•Multitenancy is a feature of cloud services that allows multiple users or customers to share the same physical or virtual resources, such as servers, databases, or applications, while maintaining isolation and privacy. Multitenancy can offer benefits such as efficiency, scalability, and cost-effectiveness, but it does not directly address the need for dynamic resource allocation for the online gaming company.

References

1: Understand cloud concepts | Microsoft Press Store

2: What Is Hybrid Cloud? - Cisco

3: Difference between Elasticity and Scalability in Cloud Computing

4: Scalability and Elasticity in Cloud Computing - GeeksforGeeks

Enhanced Interior Gateway Routing Protocol (EIGRP) uses bandwidth and delay as its primary metrics to determine the best path for routing traffic. EIGRP is an advanced distance-vector routing protocol, which is proprietary to Cisco systems, making it highly efficient in a variety of network designs. It can also utilize load, reliability, and maximum transmission unit (MTU) as additional metrics, but bandwidth and delay are the primary considerations in its composite metric calculation. Other protocols listed, such as RIP, OSPF, and BGP, use different metrics like hop count (RIP) and cost based on link state (OSPF), or make decisions based on path attributes and policy (BGP)​​.

 The issue described is related to network congestion and IP address allocation. When a tenant with a large attendance ends its session, the DHCP lease time of 24 hours means that the IP addresses used by that tenant’s attendees are not released back into the pool for a full day. This can lead to an exhaustion of available IP addresses for subsequent tenants.

• D. Change the DHCP scope end to 10.1.10.250: Increasing the DHCP scope end will provide more available IP addresses for allocation, reducing the likelihood of running out of addresses when there are many users.
• G. Reduce the DHCP lease time to four hours: Reducing the DHCP lease time means that IP addresses are released back into the pool more quickly after being allocated, making them available for other users sooner and reducing issues with address exhaustion.

These changes would most likely alleviate issues with users being unable to connect after sessions with large attendances.

References:

• Best practices in managing DHCP include adjusting scope and lease times according to user patterns and network demand.
• Professormesser
• CompTIA Network+ Study Guide

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.”

A cable was looped and created a broadcast storm is the most likely explanation for the symptoms of high CPU usage and blinking lights on the switch. A cable loop is a situation where a switch port is connected to another switch port on the same switch or another switch, creating a circular path for network traffic. A cable loop can cause a broadcast storm, which is a network phenomenon where a large number of broadcast or multicast packets are flooded on the network, consuming bandwidth and CPU resources. A broadcast storm can cause network congestion, performance degradation, or failure. A cable loop can occur when an employee rearranges the wiring closet without proper documentation or verification. A cable loop can be prevented or detected by using Spanning Tree Protocol (STP) or loop detection features on the switch. References: [CompTIA Network+ Certification Exam Objectives], What Is a Broadcast Storm? | Definition & Examples | Forcepoint

A firewall is a device or software that filters and controls the incoming and outgoing network traffic based on predefined rules. A firewall can block ICMP packets, which are used for ping and other diagnostic tools. If the workstation has a firewall enabled, it may not respond to the ICMP sweep and appear as offline. The engineer should check the firewall settings on the workstation and allow ICMP traffic if needed.

References: Network+ Study Guide Objective 4.1: Given a scenario, use the appropriate tool.

• A company joins a bank’s financial network and establishes a connection to the clearinghouse servers in the range 192 168.124.0/27 means that the company is using a private IP address range that is allocated to the bank’s servers, which are located on a different network.
• An IT technician then realizes the range exists within the VM pool at the data center means that the technician discovers that the same private IP address range is also used by the virtual machines (VMs) at the company’s data center, which are located on the same network as the company.
• This creates a problem, as the company cannot communicate with the bank’s servers using the private IP addresses, since they are already in use by the VMs. The company needs a way to translate the private IP addresses to public IP addresses, so that the packets can be routed across the internet to the bank’s network, and vice versa.
• NAT, or Network Address Translation, is a feature of a router that allows the router to modify the source and destination IP addresses of the packets that pass through it, according to a predefined mapping table. NAT can be used to translate private IP addresses to public IP addresses, and vice versa, to enable communication between networks that use different IP address ranges.
• NAT would be the BEST way for the technician to connect to the bank’s servers, as the technician can configure the router to map the private IP addresses of the company to a set of public IP addresses that are unique and routable on the internet, and map the public IP addresses of the bank to a set of private IP addresses that are not in use by the VMs. This way, the company can send and receive packets to and from the bank’s servers, without any IP address conflicts or overlaps.
• The other options are not correct because:

References:

• CompTIA Network+ N10-008 Certification Study Guide, Chapter 3: Network Operations, Section 3.2: Network Address Translation1
• Professor Messer’s CompTIA N10-008 Network+ Course Notes, Page 19: Network Address Translation2
• Professor Messer’s CompTIA N10-008 Network+ Training Course, Video 3.2: Network Address Translation3

An engineer will most likely use IPerf to get detailed measurement data about the user's slow file transfers. IPerf is a tool used for measuring network performance and bandwidth, and it can be used to measure the speed and throughput of file transfers from the remote office. It can also provide detailed information about the latency and jitter of the connection, which can be used to troubleshoot the slow file transfers. Reference: CompTIA Network+ Study Manual (Chapter 10, Page 214).

Firewall audit logs are records of the changes made to the firewall configuration, policies, and rules. They can help the firewall administrator to track who, when, and what changes were made to the firewall, and identify any unauthorized or erroneous modifications that could cause security issues or network outages. By consulting the firewall audit logs, the firewall administrator can investigate how the change that allowed traffic on port 80 to the web server occurred, and prevent it from happening again

A MAC filter list is a security feature that allows or denies access to a wireless network based on the MAC address of the device. A MAC address is a unique identifier assigned to a network interface card (NIC) at the physical layer of the OSI model. However, MAC filtering operates at the data link layer of the OSI model, where MAC addresses are used to encapsulate and deliver data frames between devices on the same network segment.

References: CompTIA Network+ Certification Exam Objectives Version 7.0 (N10-007), Objective 3.1: Given a scenario, install and configure wireless LAN infrastructure and implement the appropriate technologies in support of wireless capable devices.

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: (page 64)

The DHCP server is not available is the most likely cause of the issue where a new computer is unable to ping the default gateway. DHCP stands for Dynamic Host Configuration Protocol, which is a network protocol that automatically assigns IP addresses and other configuration parameters to clients on a network. The default gateway is the IP address of the router or device that connects a local network to other networks, such as the internet. Pinging is a network utility that tests the connectivity and reachability between two devices by sending and receiving echo packets. If the DHCP server is not available, the new computer will not be able to obtain an IP address or other configuration parameters, such as the default gateway, from the DHCP server. This will prevent the new computer from communicating with other devices on the network or the internet, resulting in ping failure. References: [CompTIA Network+ Certification Exam Objectives], What Is DHCP? | How DHCP Works | SolarWinds MSP

An AAAA record is a type of DNS record that maps a domain name to an IPv6 address. It is similar to an A record, which maps a domain name to an IPv4 address, but it uses a 128-bit address instead of a 32-bit one. An AAAA record allows a domain name to be resolved by both IPv4 and IPv6 clients, and it is necessary for accessing websites and services that use IPv6.

• A cold site is a recovery solution that provides a physical location with minimal or no equipment, power, or network connectivity. It is the cheapest option among the four choices, but it also requires the most time and effort to restore the applications and data in the event of a disaster12.
• A warm site is a recovery solution that provides a physical location with some equipment, power, and network connectivity, but not enough to run all the applications and data. It is more expensive than a cold site, but it also reduces the recovery time and data loss12.
• A hot site is a recovery solution that provides a physical location with fully functional equipment, power, and network connectivity, as well as a replica of the applications and data. It is the most expensive option among the four choices, but it also offers the fastest recovery time and minimal data loss12.
• A cloud site is a recovery solution that uses a cloud service provider to host the applications and data. It can offer various levels of availability, scalability, and cost, depending on the service model and the service level agreement. It can also reduce the need for physical infrastructure and maintenance13.
• For lower-priority applications, a company may choose a cold site as the most cost-effective recovery solution, as it does not require a large upfront or ongoing investment. However, the company should also consider the trade-off between cost and recovery time, as a cold site may take longer to restore the applications and data than other solutions. The company should also have a backup strategy to ensure that the data can be retrieved from a secure location12. References:
• 1: CompTIA Network+ N10-008 Certification Study Guide, Chapter 11: Network Operations, Section 11.4: Disaster Recovery2
• 2: Professor Messer’s CompTIA N10-008 Network+ Course Notes, Page 51: Disaster Recovery4
• 3: Professor Messer’s CompTIA N10-008 Network+ Course Notes, Page 52: Cloud Computing4
• 4: Professor Messer’s CompTIA Network+ N10-008 Training Course5

Wireless drivers can affect the performance and compatibility of your wireless connection5. If only a new line of laptops using the organization’s standard image has experienced slow wireless speeds, it could be that their wireless drivers are outdated or incompatible with the network. Updating the device wireless drivers could resolve this issue.

Wireless drivers play an important role in the performance of a wireless connection, as they control how the device interacts with the wireless network. If the laptops in question are using an outdated version of the wireless driver, it could be causing the slow speeds. The network administrator should recommend updating the device wireless drivers first to see if this resolves the issue.

A screened subnet is a network segment that is isolated from both the internal and external networks by firewalls or routers. It is used to host publicly accessible servers that need some protection from external attacks, but also need to be separated from the internal network for security reasons.

References

• 1: Seven-Second Subnetting – N10-008 CompTIA Network+ : 1.4
• 2: CompTIA Network+ Study Guide: Exam N10-008, 5th Edition, page 56
• 3: CompTIA Network+ N10-008 Exam Subnetting Quiz, question 22

If a network client is trying to connect to the wrong TCP port, the most likely response it would receive is a RST (reset) packet from the server. A RST packet is used to terminate a TCP connection abruptly, either because the server does not recognize the port number, or because the server has no application listening on that port, or because the server detects an error or an attack on the connection. A RST packet tells the client to stop sending any more data and close the connection immediately12

The other options are not as likely to be the responses for connecting to the wrong TCP port. A FIN (finish) packet is used to gracefully end a TCP connection, after both parties have exchanged all the data they need. A FIN packet indicates that the sender has no more data to send and is ready to close the connection. A FIN packet does not imply an error or a rejection, but rather a normal termination of the connection12

An ICMP (Internet Control Message Protocol) Time Exceeded message is used to inform the sender that a packet has been discarded because its time to live (TTL) value has reached zero. A TTL value is a counter that decrements by one every time a packet passes through a router. When the TTL value reaches zero, the packet is dropped and an ICMP Time Exceeded message is sent back to the sender. This message is used to prevent packets from looping endlessly in the network, and also to implement the traceroute tool, which shows the path and the hops that a packet takes to reach a destination. An ICMP Time Exceeded message is not related to the TCP port number, but rather to the IP routing and the TTL value3

A Redirect message is another type of ICMP message that is used to inform the sender that there is a better route to the destination. A Redirect message is sent by a router when it receives a packet from a host on the same network, and forwards the packet to another router on the same network. A Redirect message tells the sender to use the second router as the next hop, instead of the first router, to optimize the routing and avoid unnecessary hops. A Redirect message is also not related to the TCP port number, but rather to the IP routing and the network topology3

References:

• What causes a TCP/IP reset (RST) flag to be sent?
• RFC 792: Internet Control Message Protocol

Port mirroring is a feature that can be used to enable monitoring of all packets arriving at an interface. This feature is used to direct a copy of all traffic passing through the switch to a monitoring device, such as a network analyzer. This allows the switch to be monitored with the network analyzer in order to identify any malicious or suspicious activity. Additionally, port mirroring can be used to troubleshoot network issues, such as latency or poor performance.

Stratum 1 devices are the most accurate ntp time sources accessible via a network connection. A Stratum 1 device would normally be synchronised via a Stratum 0 reference clock.

Tailgating is when someone follows an authorized person into a restricted area without having the proper credentials. This is usually done by pretending to be with the authorized person, or by offering assistance. Tailgating is a social engineering attack and does not require any technical skill.

Cameras are the best tool for remotely monitoring who is accessing a secure data center. They provide real-time visual verification of individuals entering and exiting the facility and can be monitored remotely to ensure security protocols are followed. Access control vestibules, employee training, and biometrics are also important for security but do not offer the same continuous, visual monitoring capability that cameras do. Cameras also serve as a deterrent to unauthorized access and can provide forensic evidence in the event of a security breach​​.

Channel overlap is a situation where multiple wireless networks use the same or adjacent frequency channels, causing interference and degradation of performance. According to the image, the corporate SSID is using channels 9, 10, 11, and 6, which are overlapping with each other and with other networks in the area. This can reduce the signal quality and strength, increase the noise and latency, and cause dropouts and connectivity issues. To avoid channel overlap, it is recommended to use non-overlapping channels, such as 1, 6, and 11, in the 2.4 GHz band, or to switch to the 5 GHz band if possible12.

References

1 - What happens when wifi channels overlap? - Server Fault

2 - Is it better to use a crowded 2.4GHz Wi-Fi channel 1, 6, 11 or “unused” 3, 4, 8, or 9? - Super User

802.11b (Wi-Fi 1)

11 Mbps

100 meter maximum effective range

802.11a (Wi-Fi 2)

54 Mbps

50 meter maximum effective range

Data center interconnect (DCI) is a solution that allows Layer 2 connectivity and data replication between geographically dispersed data centers. DCI can be implemented using various technologies, such as optical networks, MPLS, VPNs, or Ethernet. DCI can provide benefits such as improved disaster recovery, load balancing, resource pooling, and cloud services.

References:

• Data Center Interconnect - CompTIA Network+ N10-008 Domain 1.4 - YouTube1
• CompTIA Network+ Certification Exam Objectives, page 92

TTL stands for Time to Live, and it is a field on DNS records that controls how long each record is valid and cached by the DNS resolver before it expires and requests a new one. The TTL value is measured in seconds, and it affects how quickly DNS changes propagate across the Internet. A lower TTL means that the DNS resolver will refresh the record more frequently, but it also increases the load on the DNS servers. A higher TTL means that the DNS resolver will cache the record longer, but it also delays the update of the record.

STP stands for Spanning Tree Protocol, which is a network protocol that prevents loops in a switched network by blocking redundant links. STP allows only one active path between any two network devices, and dynamically reconfigures the network topology in case of link failures or changes. STP is essential for proper stability of the network switches, especially when they are cabled in a redundant or complex topology that involves multiple switches and firewalls. Without STP, loops can cause broadcast storms, MAC address table instability, and duplicate frames, which can degrade the network performance and availability. References: [CompTIA Network+ Certification Exam Objectives], Spanning Tree Protocol (STP) Explained | NetworkLessons.com

The most likely cause of the intermittent connectivity issues when specific Wireless Access Points (WAPs) are turned on and share channel five is interference. Wireless interference occurs when multiple devices operate on the same channel within close proximity to each other, leading to signal congestion and reduced performance. This type of interference can cause the connectivity to be sporadic, as described. Other options like polarization, incorrect channel (since they are on the intended channel), or low power levels would generally not cause intermittent issues strictly when WAPs are turned on​​.

"One final usage of the TXT resource record is how some cloud service providers, such as Azure, validate ownership of custom domains. You are provided with data to include in your TXT record, and once that is created, the domain is verified and able to be used. The thought is that if you control the DNS, then you own the domain name."

The technician should be most concerned about data integrity and security. If information on the local database server was changed during a file transfer to a remote server, it could indicate that unauthorized access or modifications were made to the data. It could also indicate a failure in the file transfer process, which could result in data loss or corruption. The technician should investigate the cause of the changes and take steps to prevent it from happening again in the future. Additionally, they should verify the integrity of the data and restore it from a backup if necessary to ensure that the correct and complete data is available. The technician should also take appropriate actions such as notifying the system administrator and management of the incident, and following the incident management process to minimize the damage caused by the incident.

• The firewall logs are the best source of information to determine whether an internal server was accessed by hosts on the internet, as they record all the traffic that passes through the firewall, including the source and destination IP addresses, ports, protocols, and actions taken by the firewall rules.
• The server’s syslog is a file that records events and messages related to the server’s operation, such as system errors, warnings, or notifications. It may not contain information about the network traffic to and from the server, especially if the server was shut down during the investigation.
• The NetFlow statistics are a network protocol that collects and analyzes data about the network traffic flows, such as the volume, type, and direction of the traffic. It can provide useful information about the network performance and utilization, but it may not show the details of the individual packets or the firewall actions.
• The audit logs on the core switch are a record of the configuration changes and commands executed on the switch, such as adding, deleting, or modifying VLANs, ports, or routing protocols. They can help troubleshoot or verify the switch’s operation, but they may not show the network traffic to and from the server.

References:

• CompTIA Network+ N10-008 Study Guide, Chapter 7: Network Security, Section 7.2: Network Security Devices and Technologies, p. 372-373
• Professor Messer’s CompTIA N10-008 Network+ Course Notes, Section 5.1: Network Monitoring Tools, p. 51
• Professor Messer’s CompTIA N10-008 Network+ Training Course, Video 5.1: Network Monitoring Tools, 12:28-14:02

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

• The question asks about the command that an engineer should send before entering the DNS name to verify the external record for SMTP traffic, which is the mail exchange (MX) record.
• The MX record is a type of DNS resource record that specifies the mail server responsible for accepting email messages on behalf of a domain name.
• To query the MX record using the nslookup command, the engineer should first set the query type to MX using the command set querytype=Mx or set type=Mx.
• The other options are not correct, as they do not set the query type to MX:
• CompTIA Network+ N10-008 Study Guide, Chapter 3, Section 3.4, DNS Concepts, page 1441
• Professor Messer’s CompTIA N10-008 Network+ Course Notes, Section 3.4, DNS Concepts, page 242
• Professor Messer’s CompTIA N10-008 Network+ Training Course, Video 3.4 - DNS Concepts, 9:00 - 10:003

NS stands for Name Server, and it is a DNS record that specifies which servers are authoritative for a domain. The registrar is the entity that manages the domain registration and delegation, and it maintains the NS records for each domain. To change where the outside DNS records are hosted, the network administrator needs to change the NS records at the registrar to point to the new DNS servers that will host the outside DNS records.

References:

• DNS Record Types – N10-008 CompTIA Network+ : 1.61
• CompTIA Network+ N10-008 Cert Guide, page 1472

SNMPv3 is a protocol that allows network administrators to monitor and manage network devices such as routers, switches, servers, printers, and more. SNMPv3 provides authentication and encryption features that ensure the security and integrity of the data exchanged between the management station and the network devices. SNMPv3 uses a user-based security model (USM) that supports three levels of security: noAuthNoPriv, authNoPriv, and authPriv. The noAuthNoPriv level provides no authentication or encryption, the authNoPriv level provides authentication but no encryption, and the authPriv level provides both authentication and encryption12.

References

• SNMP is one of the common network monitoring protocols covered in Objective 3.1 of the CompTIA Network+ N10-008 certification exam3.
• SNMPv3 provides authentication and encryption features for network monitoring12.
• SNMPv3 uses a user-based security model with three levels of security12.

1: SNMP - N10-008 CompTIA Network+ : 3.1 - Professor Messer IT Certification Training Courses 2: CompTIA Network+ N10-008 Cert Guide, Chapter 13, page 413 3: CompTIA Network+ Certification Exam Objectives, page 7

• A media converter is a device that allows you to interconnect different types of network media, such as copper, fiber, and coaxial cables.
• A media converter can be used to connect newer network technologies, such as Gigabit Ethernet or ATM, to existing networks, such as 10BASE-T or 100BASE-T.
• A media converter can also be used to extend the distance and improve the immunity of network signals by converting them from electrical to optical or vice versa.
• A proxy server, an industrial control system, and a load balancer are not devices that can connect different physical characteristics of network media. They have different functions and purposes in a network.
• A proxy server is a device that acts as an intermediary between a client and a server, providing security, caching, and filtering services.
• An industrial control system is a system that monitors and controls industrial processes, such as manufacturing, power generation, and transportation.
• A load balancer is a device that distributes network traffic across multiple servers, improving performance and availability. References:
• Media Converters – CompTIA Network+ N10-006 – 1.5
• Transceivers (Media Converters) | Network+ Exam Cram: Networking Devices in Modern Networks

RDP (Remote Desktop Protocol) is the best option for a network technician to use when installing new software on a Windows-based server in a different geographical location. This protocol allows the technician to connect to the server remotely and control it as if they were physically present.

References:

• Network+ N10-007 Certification Exam Objectives, Objective 2.2: Given a scenario, implement the appropriate network-based security and troubleshoot common connectivity issues.

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.

CVE stands for Common Vulnerabilities and Exposures, which is a list of publicly disclosed cybersecurity vulnerabilities that is free to search, use, and incorporate into products and services. CVE provides a standardized identifier and description for each vulnerability, as well as references to related sources of information. CVE helps to track and document various types of known vulnerabilities and facilitates communication and coordination among security professionals.

References:

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

A default gateway is a device that routes traffic from one network to another network, such as the Internet. A default gateway is usually configured on each host device to specify the IP address of the router that connects the host’s network to other networks. In this case, the user’s device and the destination device are on different networks (192.168.1.0/24 and 192.168.2.0/24), so the user needs to configure a default gateway on their device to reach the destination device. References:

Bandwidth management is used to prioritize Internet usage per application and per user on the network. This allows an organization to allocate network resources to mission-critical applications and users, while limiting the bandwidth available to non-business-critical applications. References: Network+ Certification Study Guide, Chapter 2: Network Operations

Short Explanation: The switch feature that is most likely to be used to assist with logging IPv6 and MAC addresses of devices on a network segment is Neighbor Discovery Protocol (NDP). NDP is used by IPv6 to discover and maintain information about other nodes on the network, including their IPv6 and MAC addresses. By periodically querying NDP, the administrator can log this information for auditing purposes.

References:

• CompTIA Network+ Certification Study Guide, Exam N10-007, Fourth Edition, Chapter 2: The OSI Model and Networking Protocols, Objective 2.1: Compare and contrast TCP and UDP ports, protocols, and their purposes.

CRC stands for Cyclic Redundancy Check, and it is a type of error-detecting code used to detect accidental changes to raw data. If the CRC count is increasing on a particular interface, it indicates that there might be an issue with the cabling, which is causing data corruption. References:

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

A wireless controller is used to manage a corporate WLAN, providing centralized management and configuration of access points. References: CompTIA Network+ Certification Study Guide, Chapter 8: Wireless Networks.

The dig command is used to query the NSs for a remote application. It is a command-line tool that is commonly used to troubleshoot DNS issues. When used with specific options, dig can be used to obtain information about domain names, IP addresses, and DNS records. References: Network+ Certification Study Guide, Chapter 3: Network Infrastructure

A Layer 3 switch will likely replace all the company's hubs when implementing OSPF on all of its network devices. A Layer 3 switch combines the functionality of a traditional Layer 2 switch with the routing capabilities of a router. By implementing OSPF on a Layer 3 switch, an organization can improve network performance and reduce the risk of network congestion. References: Network+ Certification Study Guide, Chapter 5: Network Security

Tracert is a command-line tool that traces the route of a packet from a source to a destination and displays the number of hops and the round-trip time for each hop. The output shown in the question is an example of a tracert output, which shows five hops with their IP addresses and hostnames (if available) and three latency measurements for each hop in milliseconds. References:

Asset tags will allow the technician to record changes to new and old equipment when installing multiple UPS units in a major retail store. Asset tags are labels or stickers that are attached to physical assets such as computers, printers, servers, or UPS units. They usually contain information such as asset name, serial number, barcode, QR code, or RFID chip that can be scanned or read by an asset management system or software. Asset tags help track inventory, location, status, maintenance, and ownership of assets. References:

Screened Subnet devices – Web server, FTP server

Building A devices – SSH server top left, workstations on all 5 on the right, laptop on bottom left

DataCenter devices – DNS server.

A screenshot of a computer Description automatically generated

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.

BGP (Border Gateway Protocol) is a routing protocol used to exchange route information between public autonomous systems (AS). OSPF (Open Shortest Path First), EGRIP (Enhanced Interior Gateway Routing Protocol), and RIP (Routing Information Protocol) are all used for internal routing within a single AS. Therefore, BGP is the correct option to choose for this question.

References:

• Network+ N10-007 Certification Exam Objectives, Objective 3.3: Given a scenario, configure and apply the appropriate routing protocol.
• Cisco: Border Gateway Protocol (BGP) Overview

A virtual IP (VIP) address must be configured to ensure connectivity during a failover. A VIP address is a single IP address that is assigned to a group of servers or network devices. When one device fails, traffic is automatically rerouted to the remaining devices, and the VIP address is reassigned to the backup device, allowing clients to continue to access the service without interruption.

References:

• CompTIA Network+ Certification Study Guide, Exam N10-007, Fourth Edition, Chapter 6: Network Servers, p. 300

According to troubleshooting methodology, after determining the most likely probable cause of an issue, the next step is to establish a plan of action to resolve the issue and identify potential effects. This step involves defining the steps needed to implement a solution, considering the possible consequences of each step, and obtaining approval from relevant stakeholders if necessary. References:

Site-to-site VPN provides the best security for connecting a new datacenter to an old one because it creates a secure tunnel between the two locations, protecting data in transit. References: CompTIA Network+ Certification Study Guide, Chapter 5: Network Security.

A content delivery network (CDN) is a distributed network of servers that delivers web content to users based on their geographic location. By replicating content across multiple servers in various locations, a CDN can optimize speed and reduce latency in high-density user locations.

When evaluating a firewall to protect a datacenter’s east-west traffic, it is important to consider traffic between VMs running on different hosts. This type of traffic is referred to as east-west traffic and is often protected by internal firewalls. By implementing firewalls, an organization can protect their internal network against threats such as lateral movement, which can be caused by attackers who have breached a perimeter firewall. References: Network+ Certification Study Guide, Chapter 5: Network Security

TCP port 445 is used by the Windows OS for file sharing. It is also known as SMB (Server Message Block) or CIFS (Common Internet File System) and allows users to access files, printers, and other shared resources on a network. References:

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:

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.

A captive portal is a web page that requires users to authenticate before they can access the internet. If the session time-out configuration is too short, users may experience intermittent internet connectivity and have to reconnect using the web authentication process each time. The network administrator can verify the session time-out configuration on the captive portal settings and adjust it if needed. References: CompTIA Network+ Certification Exam Objectives Version 2.0 (Exam Number: N10-006), Domain 1.0 Network Architecture, Objective 1.8 Explain the purposes and use cases for advanced networking devices.

To detect the exact break point of a fiber link, an engineer should use an OTDR (Optical Time Domain Reflectometer). This device sends a series of pulses into the fiber, measuring the time it takes for the pulses to reflect back, and can pinpoint the exact location of the break.

References:

• Network+ N10-007 Certification Exam Objectives, Objective 2.5: Given a scenario, troubleshoot copper cable issues.
• FS: OTDR (Optical Time Domain Reflectometer) Testing Principle and Applications

Reverse Address Resolution Protocol (RARP) is a protocol that allows a device to obtain its MAC address from its IP address. A MAC spoofing attack is an attack where a device pretends to have a different MAC address than its actual one. RARP can be used to detect a MAC spoofing attack by comparing the MAC address obtained from RARP with the MAC address obtained from other sources, such as ARP or DHCP. References:

To improve performance for videoconferencing, the company should configure Quality of Service (QoS). This technology allows for the prioritization of network traffic, ensuring that videoconferencing traffic is given higher priority and therefore better performance. Link Aggregation Control Protocol (LACP), Dynamic routing, Network load balancer, and Static IP addresses are not directly related to improving performance for videoconferencing.

References:

• Network+ N10-007 Certification Exam Objectives, Objective 2.6: Given a scenario, implement and configure the appropriate wireless security and implement the appropriate QoS concepts.

If multiple users in a new building are unable to access the company’s intranet site via their web browser but are able to access internet sites, the network administrator can resolve this issue by correcting the DNS server entries in the DHCP scope. The DHCP scope is responsible for assigning IP addresses and DNS server addresses to clients. If the DNS server entries are incorrect, clients will not be able to access intranet sites.

References:

• CompTIA Network+ Certification Study Guide, Exam N10-007, Fourth Edition, Chapter 4: Network Implementations, Objective 4.4: Explain the purpose and properties of DHCP.

CSMA/CA (Carrier Sense Multiple Access with Collision Avoidance) is an IEEE 802.11 standard that would be best to use for multiple simultaneous client access on a wireless network. CSMA/CA is a media access control method that allows multiple devices to share the same wireless channel without causing collisions or interference. It works by having each device sense the channel before transmitting data and waiting for an acknowledgment from the receiver after each transmission. If the channel is busy or no acknowledgment is received, the device will back off and retry later with a random delay. References:

 Port 23 should be blocked when checking firewall configuration to prevent outside users from telnetting into any of the servers at the datacenter. Port 23 is the default port for Telnet, which is an insecure protocol that allows remote access to servers and network devices. Telnet sends data in clear text, which can be easily intercepted and compromised by attackers. A more secure alternative is SSH, which uses port 22 and encrypts data. References:

NIC teaming, also known as network interface card teaming or link aggregation, allows multiple network interface cards to be grouped together to provide redundancy and increased throughput. In the event of a port failure on a switch, NIC teaming ensures that the file server remains connected to the LAN by automatically switching to another network interface card.

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

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

TTL (Time To Live) should be adjusted to address the issue of some visitors being unable to access the website after the A record was updated. TTL is a value that specifies how long a DNS record should be cached by DNS servers and clients before it expires and needs to be refreshed. If the TTL is too high, some DNS servers and clients may still use the old A record that points to the previous IP address of the website, resulting in connection failures. By lowering the TTL, the DNS servers and clients will update their cache more frequently and use the new A record that points to the current IP address of the website. References:

To locate a device's network port on a switch, a technician should review the switch's MAC address table. The MAC address table maintains a list of MAC addresses of devices connected to each port on the switch. By checking the MAC address of the device in question, the technician can identify the port to which the device is connected.

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

A reservation should be configured to ensure a device with a specific MAC address is always assigned the same IP address from DHCP. A reservation is a feature of DHCP that allows an administrator to assign a fixed 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, even if it is powered off or disconnected from the network for a long time. References:

The reason why the alerts are not being received is that the network device is not configured to log that level to the syslog server. The severity level for the events may need to be adjusted in order for them to be sent to the syslog server. References: Network+ Certification Study Guide, Chapter 8: Network Troubleshooting

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:

IDS stands for intrusion detection system, which is a network appliance that monitors network traffic and alerts administrators of any suspicious or malicious activity. An IDS can warn of unapproved devices that are accessing the network by detecting anomalies, signatures, or behaviors that indicate unauthorized access attempts or attacks. References:

A broadcast storm is most likely occurring when connecting multiple unmanaged Layer 2 switches with multiple connections between each pair. A broadcast storm is a situation where broadcast packets flood a network segment and consume all the available bandwidth. It can be caused by loops in the network topology, where broadcast packets are endlessly forwarded by switches without any loop prevention mechanism. Unmanaged switches do not support features such as Spanning Tree Protocol (STP) or Rapid Spanning Tree Protocol (RSTP) that can detect and block loops. References:

A subnet mask is a binary number that indicates which bits of an IP address belong to the network portion and which bits belong to the host portion. A slash notation (/n) indicates how many bits are used for the network portion. A /20 notation means that 20 bits are used for the network portion and 12 bits are used for the host portion. To convert /20 to a dotted decimal notation, we need to write 20 ones followed by 12 zeros in binary and then divide them into four octets separated by dots. This gives us 11111111.11111111.11110000.00000000 or 255.255.240.0 in decimal. References:

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:

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.

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.

On the first exhibit, the layout should be as follows

Graphical user interface, text, application, chat or text message Description automatically generated

Graphical user interface Description automatically generated

Graphical user interface, text, application, chat or text message Description automatically generated

Graphical user interface Description automatically generated

Exhibit 2 as follows

Access Point Name AP2

Graphical user interface Description automatically generated

Graphical user interface, text, application, chat or text message Description automatically generated

Graphical user interface Description automatically generated

Exhibit 3 as follows

Access Point Name AP3

Graphical user interface Description automatically generated

Graphical user interface, text, application, chat or text message Description automatically generated

Graphical user interface Description automatically generated

A change management policy is a document that outlines the procedures and guidelines for making changes to a network or system, including how changes are approved, tested, and implemented. By following a change management policy, organizations can ensure that unnecessary modifications to the network are not permitted and version control is maintained. References:

• Network+ N10-008 Objectives: 1.6 Given a scenario, implement network configuration and change management best practices.

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:

Port security is a feature that restricts input to a switch port by limiting and identifying MAC addresses of the devices allowed to access the port. This prevents unintended connections from unauthorized devices or spoofed MAC addresses. Port security can also be configured to take actions such as shutting down the port or sending an alert when a violation occurs. References:

Channel overlap is a common cause of wireless connectivity issues, especially in high-density environments where multiple APs are operating on the same or adjacent frequencies. Channel overlap can cause interference, signal degradation, and performance loss for wireless devices. The AP association time, EIRP, and RSSI are not likely to cause frequent disconnects and reconnects for wireless users.

To resolve the issue of DHCP scope exhaustion without creating a new DHCP pool, the administrator can reduce the lease time. By decreasing the lease time, the IP addresses assigned by DHCP will be released back to the DHCP scope more quickly, allowing them to be assigned to new devices.

References:

• CompTIA Network+ Certification Study Guide, Exam N10-007, Fourth Edition, Chapter 2: The OSI Model and Networking Protocols, Objective 2.3: Given a scenario, implement and configure the appropriate addressing schema.
• https://www.networkcomputing.com/data-centers/10-tips-optimizing-dhcp-performance

802.11ax is the latest WiFi standard that improves WiFi performance in densely populated environments and supports both 2.4 GHz and 5 GHz bands. 802.11ac is the previous standard that only supports 5 GHz band. 802.11g and 802.11n are older standards that support 2.4 GHz band only or both bands respectively. References:

The network administrator should check the roaming settings on the APs and WLAN clients first. Roaming is the process of switching from one AP to another without losing connectivity. If the roaming settings are not configured properly, some users may experience poor connectivity when their devices stay connected to a distant AP instead of switching to a closer one. References:

TACACS+ (Terminal Access Controller Access Control System Plus) can be used to centrally manage credentials for various types of administrative privileges on configured network devices. This protocol separates authentication, authorization, and accounting (AAA) functions, providing more granular control over access to network resources.

References:

• Network+ N10-007 Certification Exam Objectives, Objective 4.2: Given a scenario, implement secure network administration principles.

East-West traffic refers to data flows between servers or devices within the same datacenter. When a hosted virtual server is duplicated to another physical server for redundancy, it generates significant East-West traffic as the data is replicated between the two servers. References:

• Network+ N10-008 Objectives: 3.3 Given a scenario, implement secure network architecture concepts.

An extended service set (ESS) is a wireless network that consists of multiple access points (APs) that share the same SSID and are connected by a wired network. An ESS allows wireless clients to roam seamlessly between different APs without losing connectivity. A basic service set (BSS) is a wireless network that consists of a single AP and its associated clients. An independent basic service set (IBSS) is a wireless network that consists of a group of clients that communicate directly without an AP. A unified service set is not a standard term for a wireless network. References:

The IP address configured on the router interface is 196.26.4.1/26, which belongs to the IP range assigned by the ISP (196.26.4.0/26). However, this IP address is not valid for this interface because it is the network address of the subnet, which cannot be assigned to any host device. The network address is the first address of a subnet that identifies the subnet itself. The valid IP addresses for this subnet are from 196.26.4.1 to 196.26.4.62, excluding the network address (196.26.4.0) and the broadcast address (196.26.4.63). The router interface should be configured with a valid IP address within this range to restore Internet connectivity for all users. References:

The issue of WIFI users being unable to connect while WLAN users on the guest network can access all resources indicates a problem with channel overlap or interference. By reconfiguring the channels, interference can be minimized, improving connectivity for WIFI users. According to the table, AP 1 and AP 2 are using adjacent channels (2 and 1), which can cause interference. AP 3 and AP 4 are using non-overlapping channels (5 and 11), but they have very high RSSI values (-44dBm and -41dBm), which can also cause interference. A possible solution is to use only non-overlapping channels (such as 1, 6, and 11) and adjust the power levels to avoid excessive signal strength. References: Wireless Troubleshooting – N10-008 CompTIA Network+ : 5.4, Network Troubleshooting Methodology - N10-008 CompTIA Network+ : 5.1

The attacker attempting to find the password to a network by inputting common words and phrases in plaintext to the password prompt is using a dictionary attack. References: CompTIA Network+ Certification Study Guide, Chapter 6: Network Attacks and Mitigation.

TCP/UDP port 5060 is commonly used by VoIP phones. It is the default port for SIP (Session Initiation Protocol), which is a signaling protocol that establishes, modifies, and terminates multimedia sessions over IP networks. SIP is widely used for VoIP applications such as voice and video calls. References:

The DNS record that works as an alias to another record is called CNAME (Canonical Name). CNAME records are used to create an alias for a domain name that points to another domain name.

References:

• CompTIA Network+ Certification Study Guide, Exam N10-007, Fourth Edition, Chapter 2: The OSI Model and Networking Protocols, Objective 2.3: Given a scenario, implement and configure the appropriate addressing schema.

The most effective security mechanism against physical intrusions due to stolen credentials would likely be a combination of several of these options. However, of the options provided, the most effective security mechanism would probably be an access control vestibule. An access control vestibule is a secure area that is located between the outer perimeter of a facility and the inner secure area. It is designed to provide an additional layer of security by requiring that individuals pass through a series of security checks before being allowed access to the secure area. This could include biometric authentication, access card readers, and motion detection cameras.

Access control vestibules allow the enforcement of the policy that access to a datacenter should be individually recorded by a card reader even when multiple employees enter the facility at the same time. An access control vestibule is a physical security device that consists of two doors with an interlocking mechanism. Only one door can be opened at a time, and only one person can pass through each door. This prevents tailgating or piggybacking, where unauthorized persons follow authorized persons into a secure area. An access control vestibule can also be integrated with a card reader or other authentication system to record each individual’s access. References:

 Explanation: Tailgating is a physical security attack where an unauthorized person follows an authorized person into a restricted area without proper identification or authorization. The network administrator prevented this attack by stopping and directing the person to the security desk. References: CompTIA Network+ Certification Exam Objectives Version 2.0 (Exam Number: N10-006), Domain 3.0 Network Security, Objective 3.1 Compare and contrast risk-related concepts.

Spanning Tree Protocol (STP) should be enabled when configuring redundant network links between switches. STP ensures that only one active path is used at a time, preventing network loops and stability issues.

References:

• CompTIA Network+ Certification Study Guide

FTP (File Transfer Protocol) is a system that would most likely be found in a screened subnet. A screened subnet, or triple-homed firewall, is a network architecture where a single firewall is used with three network interfaces. It provides additional protection from outside cyber attacks by adding a perimeter network to isolate or separate the internal network from the public-facing internet1. A screened subnet typically hosts systems that need to be accessed by both internal and external users, such as web servers, email servers, or FTP servers. References: 1

The maximum transmission unit (MTU) is the largest size of a data packet that can be transmitted over a network. A standard Ethernet frame supports an MTU of 1500 bytes, which is the default value for most Ethernet networks. Larger MTUs are possible with jumbo frames, but they are not widely supported and may cause fragmentation or compatibility issues. References:

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.

An IP header can be found at the third layer of the OSI model, also known as the network layer. This layer is responsible for logical addressing, routing, and forwarding of data packets.

References:

• CompTIA Network+ Certification Study Guide, Exam N10-007, Fourth Edition, Chapter 2: Network Models, p. 82

Updating the firewalls with current firmware and software is an important step to ensure all the firewalls are hardened successfully, as it can fix any known vulnerabilities or bugs and provide new features or enhancements. Enabling an implicit permit rule is not a good practice for firewall hardening, as it can allow unwanted traffic to pass through the firewall. Configuring the log settings on the firewalls to the central syslog server is a good practice for monitoring and auditing purposes, but it does not harden the firewalls themselves. Using the same complex passwords on all firewalls is not a good practice for password security, as it can increase the risk of compromise if one firewall is breached. References: CompTIA Network+ Certification Exam Objectives Version 2.0 (Exam Number: N10-006), Domain 3.0 Network Security, Objective 3.3 Given a scenario, implement network hardening techniques.

Change management is the process of reviewing previous upgrades to a system. It is a systematic approach to managing changes to an organization's IT systems and infrastructure. Change management involves the assessment of potential risks associated with a change, as well as the identification of any necessary resources required to implement the change. References: Network+ Certification Study Guide, Chapter 8: Network Troubleshooting

The ifconfig eth0 promisc command should be run on the Linux computer to enable promiscuous mode, which allows the computer to capture all network traffic passing through the switch mirror port. References: CompTIA Network+ Certification Study Guide, Chapter 7: Network Devices.

SSID (Service Set Identifier) is a feature that should be configured to allow different wireless access through the same equipment. SSID is the name of a wireless network that identifies it from other networks in the same area. A wireless access point (AP) can support multiple SSIDs with different security settings and network policies. For example, a store owner can create one SSID for business equipment and another SSID for patron use, and assign different passwords, VLANs, and QoS levels for each SSID. References:

MDIX (medium-dependent interface crossover) is a feature that allows network devices to automatically detect and configure the appropriate cabling type, eliminating the need for crossover cables. By enabling MDIX on the switches, a technician can use the original Cat 6 cable to create a crossover connection.

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

• The question asks about the metrics that will most accurately show the underlying performance issues of slow or unresponsive desktops for users who are using VMs (virtual machines).
• VMs are software-based simulations of physical computers that run on a host system. They share the resources of the host system, such as CPU, memory, disk space, etc.
• If the host system does not have enough resources to support the number of VMs running on it, the performance of the VMs will suffer. This is especially true if the VMs are running resource-intensive applications or tasks.
• Therefore, the metrics that will most accurately show the underlying performance issues are CPU usage and memory. These metrics indicate how much of the host system’s resources are being consumed by the VMs and how much is available for other processes.
• The other metrics are not relevant to the question, as they are related to the network performance, not the host system performance. They are:

References:

• CompTIA Network+ N10-008 Study Guide, Chapter 1: Networking Concepts, Section 1.3: Virtualization and Network Storage Technologies, Pages 34-36
• Professor Messer’s CompTIA N10-008 Network+ Course, Video 1.3: Virtualization and Network Storage Technologies, Part 1
• Network + N10-008 practice exam, Question 8, Answer A and B, Explanation

In a star topology, all devices on a network connect to a central hub or switch, which acts as a common connection point. Ethernet LANs typically use a star topology, with each device connected to a central switch. References:

• Network+ N10-008 Objectives: 2.2 Explain common logical network topologies and their characteristics.

Next-generation firewalls can provide content filtering and threat protection, and can manage multiple IPSec site-to-site connections. References: CompTIA Network+ Certification Study Guide, Chapter 5: Network Security.

Using a bottom-to-top approach means starting from the physical layer and moving up the OSI model to troubleshoot a network problem. Checking for a link light is a physical layer check that verifies the connectivity of the network cable and device. References:

Implementing file integrity monitoring (FIM) would assist with detecting activities such as website defacement or internal system attacks. FIM is a process that monitors and alerts on changes to files or directories that are critical for security or functionality. FIM can help detect unauthorized modifications, malware infections, data breaches, or configuration errors. FIM can also help with compliance and auditing requirements. References:

SFP (Small Form-factor Pluggable) is a connector type that has the most flexibility. It is a hot-swappable transceiver that can support different speeds, distances, and media types depending on the module inserted. It can be used for both copper and fiber connections and supports various protocols such as Ethernet, Fibre Channel, and SONET. References:

To determine what metrics can be gathered from a given switch, a technician should utilize the Management Information Base (MIB). The MIB is a database of network management information that is used to manage and monitor network devices. It contains information about device configuration, status, and performance. References: Network+ Certification Study Guide, Chapter 5: Network Security

To find all devices connected within a network, a technician can use an IP scanner. An IP scanner sends a ping request to all IP addresses within a specified range and then identifies the active devices that respond to the request.

The most likely cause of the issue where the fiber connection from a device to a switch is not working is that the TX/RX (transmit/receive) is reversed. When connecting fiber optic cables, it is important to ensure that the TX of one device is connected to the RX of the other device and vice versa. If the TX/RX is reversed, data cannot be transmitted successfully.

References:

• CompTIA Network+ Certification Study Guide, Exam N10-007, Fourth Edition, Chapter 5: Network Operations, Objective 5.1: Given a scenario, use appropriate documentation and diagrams to manage the network.

 The software on the workstation should be configured to send the query to 10.1.2.255, which is the local subnet broadcast address. A broadcast address is a special address that allows a device to send a message to all devices on the same subnet. It is usually derived by setting all the host bits to 1 in the network address. In this case, the network address is 10.1.2.0/27, which has 27 network bits and 5 host bits. By setting all the host bits to 1, we get 10.1.2.31 as the broadcast address in decimal notation, or 10.1.2.255 in dotted decimal notation. References:

Zero Trust is a security framework that requires all users, whether in or outside the organization’s network, to be authenticated, authorized, and continuously validated for security configuration and posture before being granted or keeping access to applications and data. Zero Trust prevents attackers from moving laterally through a system by applying granular policies and controls based on the principle of least privilege and by segmenting and encrypting data flows across the network. References:

The nslookup command should be run to confirm the server name for all Linux servers. Nslookup is a tool that queries DNS servers to resolve hostnames to IP addresses or vice versa. It can also provide other information about DNS records, such as MX, NS, SOA, etc. By running nslookup with the IP address of a Linux server, the technician can obtain its hostname. References:

A spectrum analyzer is a tool that measures the frequency and amplitude of signals in a wireless network. It can be used to troubleshoot issues related to interference from other networks and non-802.11 devices, such as microwave ovens or cordless phones, by identifying the sources and levels of interference in the wireless spectrum. A spectrum analyzer can also help to optimize the channel selection and placement of wireless access points. References: n10-008-exam-objectives-(2-0),

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:

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:

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.

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:

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:

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:

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 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:

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 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:

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:

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: 1

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.

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:

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.

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:

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:

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:

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:

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:

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:

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:

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:

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:

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:

 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:

 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:

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:

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:

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:

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:

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: 1

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:

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:

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.

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:

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:

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:

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.

 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:

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.

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:

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:

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:

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:

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.

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:

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:

 A UTM appliance stands for Unified Threat Management appliance, which is a device that combines multiple security functions into one solution. A UTM appliance can provide firewall, IDS/IPS, antivirus, VPN, web filtering, and other security features. A network technician can use a UTM appliance in place of an edge firewall and an IDS to prevent future attacks, as a UTM appliance can block malicious traffic and detect and respond to intrusions more effectively. References:

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:

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:

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.

 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: 1

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:

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 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:

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:

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:

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:

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:

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:

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: 1

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:

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:

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:

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:

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:

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.

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.

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: 1

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: