CompTIA Network+ Practice Test (N10-009)

Channel width in wireless networking determines the range of frequencies that a wireless signal uses on a specific channel. A wider channel width allows for more data to be transmitted simultaneously, increasing throughput but potentially increasing interference with other channels if not managed properly. This concept is fundamental in optimizing the performance of wireless networks.

A public network deployment model is characterized by its open accessibility to general internet users and is typically used to operate services meant for the general public, such as email services, social media, and public websites. The correct answer best represents this definition as it refers to hosting a website accessible to anyone on the internet, which is one of the most common uses of public networks. The other answers, while plausible, involve scenarios more typical of private or protected environments.

A mesh network efficiently extends Wi-Fi coverage across multiple areas without needing physical cables connecting each access point. This benefit is crucial in environments like large office buildings where cabling can be intrusive, expensive, or physically impractical to install in certain areas. Better bandwidth utilization and increased broadcast traffic are not inherent benefits of mesh networks; in fact, mesh networks can introduce challenges in these areas unless carefully managed.

Implementing and configuring DNSSEC on servers targets the root cause of malicious traffic redirection by authenticating the origins of the data, ensuring that the data integrity is maintained. This specific alignment with protecting against unauthorized changes and redirection aids in counteracting the effects of malicious web traffic redirection techniques. Other options, while beneficial for overall security, do not specifically authenticate the source of web traffic data, which is crucial in mitigating this type of attack.

The "show power inline" command lists the global PoE budget and a table for every PoE-capable interface showing current draw, maximum allocated power, and operational status. This information lets a technician verify that enough power is available and identify ports that have exceeded or been denied power. Other commands shown do not provide per-port PoE consumption details.

The correct answer specifies a specific range of IP addresses from 169.254.0.1 to 169.254.255.254, which are designated for automatic assignment by the host in the event that DHCP server communication is unsuccessful. This range is within the 169.254.0.0/16 subnet, reserved specifically for this purpose by networking standards to prevent IP conflicts with addresses assigned elsewhere.

Inspecting the Hosts file can confirm if there are any manually configured hostname mappings, which might be causing these redirections. The Hosts file can contain entries that override DNS resolutions, directly leading to websites being misdirected. This step is fundamental before considering broader DNS issues or network settings, making it the most direct and effective approach.

SNMPv3 is the correct choice because it provides enhanced security features including authentication, encryption, and access control, which are not supported by earlier versions like SNMPv1 and SNMPv2c. SNMPv1 and SNMPv2c do not include mechanisms for securing SNMP traffic, making them less suitable for environments where security is a concern.

A wireless survey and the resulting heat map are used primarily to assess the coverage and strength of wireless signals across different areas in a network environment. This ensures optimal placement of wireless access points and helps in identifying areas with poor connectivity or signal interference. The heat map visually represents the wireless signal strength and coverage, allowing for more informed decisions regarding infrastructure improvements.

RADIUS primarily functions as a protocol that provides centralized Authentication, Authorization, and Accounting management for users who connect and use a network service. Authentication verifies who the user is, Authorization determines what a user can and cannot access, and Accounting keeps track of the consumption of network resources by the user. The other options, while plausible-sounding, are incorrect because they do not describe the main functionalities provided by RADIUS.

PCI DSS Requirement 4 states that cardholder data must be protected with strong cryptography during transmission over any open, public network. Implementing secure protocols such as TLS 1.2 or higher (or other PCI-approved encryption methods) satisfies this control. Compressing data, sending it in clear text within a private VLAN, or merely masking some digits of the PAN do not meet the requirement because none of those tactics provide the mandatory strong encryption of the entire data stream.

The communication problem stems from the use of differing network masks which logically places the devices on different subnets, despite being physically on the same network segment. Aligning both devices to the same network mask resolves this discrepancy by placing them on the same logical network, thereby facilitating direct communication. Modifying individual addresses or segmenting the network further does not confront the root cause, which is the mismatch in network masks. Changing network cables is unrelated to an issue caused by subnet configuration.

MTTR is the average amount of time required to diagnose, repair, and fully restore a device or system after a failure has been detected. It spans detection, troubleshooting, replacement or repair, and verification that normal operation has resumed. It does not describe the interval between failures (MTBF), the allowable data-loss window (RPO), or merely the time to notice a fault.

The tracert (or traceroute on Unix/Linux systems) command is used to determine the route taken by packets across an IP network on their way to a specific host. It can identify where packets start to fail to reach the destination, showing each hop in the path and the time taken to get from one node to another. This makes it invaluable for identifying at which hop in the network path packets are potentially being dropped. In contrast, ping is effective for checking reachability and round-trip times but does not show the path of the packets. netstat displays protocol statistics and current TCP/IP network connections, which is not suitable for tracing the path of packets. ipconfig (or ifconfig in Unix/Linux) is primarily used to display all current TCP/IP network configuration values and refresh DHCP and DNS settings, but isn't useful for tracing packet paths.

The primary purpose of the ping command is to test the reachability of a host on an IP network and measure the round-trip time for messages sent from the originating host to a destination computer. This is crucial for initially diagnosing connectivity issues. Answers involving speed testing or direct problem resolution are incorrect because ping does not measure network speed in terms of throughput and cannot resolve the problems itself; it merely checks connectivity and latency.

An increase in the Cyclic Redundancy Check (CRC) counter usually indicates that there have been errors in the transmission of data frames due to issues such as noise, interference, or problems with the network cable. CRC is a form of error detection that checks the accuracy of data on the network. If the data is altered due to interference, the CRC values will not match, which is flagged as an error.

The issue described pertains to the end-to-end delivery of data packets, which falls predominantly under the Transport layer, Layer 4 of the OSI model. This layer is responsible for ensuring complete data transfer. If the application receives the request and processes it, but no response is received by the users, it could mean there is a failure in the reassembly or acknowledgment of packets, which are handled at Layer 4. The Network layer mainly deals with data packet forwarding including routing through different paths in the network, which is not primarily concerned with the bidirectional flow and control acknowledgments of the establishment maintained by the Transport layer.

Accurate cable maps are crucial for efficient troubleshooting and management of the network. They assist in quick identification of connection points and paths, thereby reducing downtime and simplifying maintenance tasks. Incorrect maps can lead to confusion, increased troubleshooting times, and potential errors during network upgrades or repairs.

By implementing port mirroring to mirror the traffic to and from the database server to an analysis tool, the administrator can conduct a comprehensive examination of the traffic. This enables the identification of specific packet types, sources, or unusual activity without interrupting server operation. Setting a QoS policy might help in managing traffic but does not provide the detailed insight needed for diagnosis. Reviewing firewall logs could miss detailed traffic content, and optimizing database queries is unrelated until the specific traffic cause is identified.

Cisco Discovery Protocol (CDP) is specifically designed for collecting detailed data about directly connected Cisco devices, including hardware model and software version. This makes CDP the best choice in networks predominantly utilizing Cisco equipment, as it can gather extensive device-specific information without manual configuration on each connected device. While LLDP also serves to discover device information on a network, it is vendor-neutral and may not provide the same level of detail for specific Cisco device characteristics compared to CDP. The command line provides a manual method to extract information and does not automate the process. SNMP, primarily used for monitoring and managing network devices, focuses more broadly on performance metrics rather than specific device information like model and software version.