The netstat command provides information about network connections, routing tables, interface statistics, masquerade connections, and multicast memberships. Running netstat on the server can help the administrator verify that the web server process is listening on the expected port (e.g., port 80 for HTTP or port 443 for HTTPS) and that there are no issues with network connections. This is a crucial first step in diagnosing why the web server is not accessible via a browser.References: CompTIA Network+ study materials. ​

DHCP snooping is a security feature on network switches that helps to prevent unauthorized (rogue) DHCP servers from assigning IP addresses to clients. By implementing DHCP snooping, the network administrator can restrict DHCP responses to authorized servers only, preventing unauthorized DHCP configurations, such as incorrect DNS IPs, from being assigned to clients. This helps prevent man-in-the-middle attacks where malicious actors misconfigure DNS to redirect users to fraudulent sites. (Reference: CompTIA Network+ Study Guide, Chapter on Network Security)

•API (Application Programming Interface) enables secure and granular access control, remote management, and logging, making it ideal for network monitoring.

•SNMP (A) is mainly used for device monitoring but lacks centralized logging and user-based privilege control.

•SIEM (C) is a security monitoring tool focused on log collection, not device management.

•SSO (D) is related to authentication, not monitoring.

???? Reference: CompTIA Network+ N10-009 Official Documentation – Network Monitoring & Management Technologies.

URL filtering can block access to websites based on their domain or country code TLDs (e.g., .cn, .ru). This is the correct method to block by location identifiers in URLs.

B. Content filtering blocks based on keywords or categories within websites, not country code.

C. DNS poisoning is an attack, not a control mechanism.

D. MAC filtering restricts devices, not websites.

References (CompTIA Network+ N10-009):

Domain: Network Security — Filtering technologies, URL vs content filtering.

WPA3-Enterprise provides strong security and supports authentication using domain identities through a RADIUS server and 802.1X authentication. This is the best choice for a corporate environment requiring user-based authentication.

WPA3-Enterprise Benefits:

Uses 802.1X with EAP (Extensible Authentication Protocol) to authenticate users via a directory service (e.g., Active Directory).

Eliminates shared passwords (PSK) for authentication.

Provides strong encryption and resistance to brute-force attacks.

Incorrect Options:

A. Enable MAC Security:

MAC filtering is not secure because MAC addresses can be spoofed.

B. Generate a PSK for Each User:

Pre-shared keys (PSK) are used in WPA-Personal, not in an enterprise setting.

Does not scale well in corporate environments.

C. Implement WPS:

Wi-Fi Protected Setup (WPS) is a vulnerable security method meant for home users.

Not suitable for enterprise authentication.

Port security is a Layer 2 security feature that restricts the number of devices connecting to a network switch port. It helps prevent unauthorized devices, such as an unmanaged switch, from being connected to the network.

How Port Security Works:

Limits the number of MAC addresses that can connect to a port.

Can shut down or restrict the port if an unauthorized device is detected.

Prevents users from plugging in unauthorized networking equipment (e.g., unmanaged switches, hubs).

Incorrect Options:

A. Screened Subnet: A screened subnet (DMZ) is used for isolating external-facing servers, not for controlling unauthorized network connections.

B. 802.1X: Provides authentication for devices but requires a RADIUS server, which is a more complex solution than port security.

C. MAC Filtering: Controls which MAC addresses can connect but is difficult to manage and can be spoofed.

BGP (Border Gateway Protocol) is the only dynamic routing protocol used across the internet. It ' s classified as an Exterior Gateway Protocol (EGP), responsible for routing between different autonomous systems (ASes).

A. EIGRP and D. OSPF are Interior Gateway Protocols (IGPs), used within organizations.

C. RIP is an outdated IGP with limited use, unsuitable for internet-scale routing.

???? Reference:

CompTIA Network+ N10-009 Official Objectives: 3.1 – Compare and contrast various routing technologies.

The best answer is B. 255.255.252.0 , which is a /22 mask. A Class B network starts with a default mask of 255.255.0.0 or /16 . The question says the administrator wants four equal subnets , which means borrowing 2 bits from the host portion, since 2 borrowed bits gives 2² = 4 subnets . That moves the mask from /16 to /18 if subnetting is based only on splitting the Class B into four equal parts.

However, the answer choices point toward the host requirement as the deciding factor. Each subnet needs to support about 1,000 hosts . A /22 leaves 10 host bits , which gives 2¹⁰ = 1024 total addresses , or 1022 usable hosts after subtracting the network and broadcast addresses. That fits the requirement. Among the options provided, 255.255.252.0 is the only mask that supports around 1,000 hosts per subnet.

The smaller masks, /24 and /25 , do not allow enough hosts. The default Class B mask, /16 , does not subnet the network at all. Based on the available choices and the host-capacity requirement, 255.255.252.0 is the correct exam answer.

The correct answer is B. Active-passive approach. CompTIA Network+ N10-009 includes high availability and disaster recovery concepts such as failover, redundancy, and recovery strategies. An active-passive approach uses a primary production system, site, or service that actively handles traffic, while a secondary standby environment remains ready to take over if the primary environment fails. This design helps ensure data center services can be restored and made accessi ble quickly after a disaster because the standby environment is already planned and prepared for failover.

Backup and replication software is important for data protection, but backups alone do not guarantee that services will be quickly available. Restoring systems from backups may require significant time. Cloud computing can support disaster recovery, but it is a broad deployment model rather than a specific recovery strategy. Remote manual failover can restore services, but manual failover usually takes longer and increases the chance of administrative delay or error.

Because the question emphasizes quickly restored and accessible services after a disaster, an active-passive approach is the most appropriate option. It provides a standby recovery environment designed to assume operations when the active data center service becomes unavailable.

Microwaves are known to interfere with the 2.4GHz frequency, which is the same frequency used by many wireless networks. This can cause signal degradation and intermittent connectivity issues, especially if the WAP is placed near such devices.

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On Core-SW01, the ports are configured with LACP (mode active) for link aggregation. On Core-SW02, the ports are configured as independent trunks, not as part of an LACP group. Because of this mismatch, LACP cannot form the bundle, and the aggregated ports on SW01 will go into a suspended state.

A. CRC errors suggest cabling or signal integrity issues, not config mismatch.

B. Error disabled occurs when a violation (like BPDU guard or port security) disables the port, not LACP mismatch.

C. Administratively down indicates a shutdown command, not the case here.

References (CompTIA Network+ N10-009):

Domain: Network Troubleshooting — Port-channel/LACP configuration issues, interface states.

WPA2/WPA3 mixed mode provides compatibility for older devices (that only support WPA2) while allowing newer devices to take advantage of stronger WPA3 encryption. This ensures maximum compatibility and security in a mixed-device environment.

A. WPA3 only is most secure but not compatible with legacy devices.

B. WPA2 only is secure but does not future-proof against WPA3-capable devices.

D. WPA/WPA2 mixed mode is weaker due to WPA (deprecated, insecure).

References (CompTIA Network+ N10-009):

Domain: Network Security — Wi-Fi encryption standards, WPA2 vs WPA3, mixed-mode compatibility.

Packet loss occurs when network packets fail to reach their destination, leading to disruptions in connectivity and performance issues. In this scenario:

Users report connectivity issues and lag during video meetings.

The administrator detects increased retransmissions in tcpdump, which is a strong indicator of lost packets that must be resent.

Video meetings are particularly sensitive to packet loss, leading to buffering, frozen screens, and dropped calls.

Latency (Option A) refers to delayed data transmission but does not necessarily cause retransmissions.

Bottlenecking (Option C) happens when a network component (e.g., router, switch) cannot handle the traffic load, but packet retransmissions are more directly related to packet loss.

Jitter (Option D) affects the consistency of packet arrival times, but the symptoms described here are more aligned with packet loss rather than timing variations.

? Reference: CompTIA Network+ (N10-009) Official Study Guide – Section: Troubleshooting Connectivity Issues