N10-009 Practice Test 14 — 15 Questions

Question 1

A network monitoring tool uses SNMP to collect data from devices. What is the primary purpose of SNMP traps?

Accepted Answer

To enable devices to send unsolicited alerts to the management system. SNMP traps are unsolicited messages sent by an SNMP agent to the network management system (NMS) to immediately notify it of a significant event, such as a link failure or high CPU utilization. This push mechanism allows the NMS to react in real time without having to poll the device, reducing bandwidth and processing overhead. The correct answer is B because traps are specifically designed for asynchronous alerting, not for polling, encryption, or authentication.

Answer

To allow a manager to poll devices for current status

Answer

To encrypt SNMP communications

Answer

To provide authentication for SNMP messages

Question 2

A network administrator wants to automate IP address assignment for client devices. Which protocol should be used?

Accepted Answer

DHCP. DHCP (Dynamic Host Configuration Protocol) automates IP address assignment by leasing IP configurations to client devices from a defined pool. This eliminates the need for manual static IP configuration, making it the correct protocol for automated IP address management.

Answer

DNS

Answer

ARP

Answer

ICMP

Question 3

A network architect is implementing a Software-Defined Networking (SDN) solution. The SDN controller needs to communicate with the physical switches to install flow rules. Which type of API is used for this communication?

Accepted Answer

Southbound API. The Southbound API is the correct interface because it enables the SDN controller to communicate with the underlying physical or virtual network devices (switches, routers) to install flow rules, modify forwarding tables, and gather telemetry. This API typically uses protocols such as OpenFlow, NETCONF, or OVSDB to translate controller decisions into device-level actions, making it the essential southbound channel in an SDN architecture.

Answer

Northbound API

Answer

Eastbound API

Answer

Westbound API

Question 4

A junior network technician asks which device operates at Layer 2 of the OSI model and uses MAC addresses to forward frames. Which device is the technician describing?

Accepted Answer

Switch. A switch operates at Layer 2 (Data Link layer) of the OSI model and uses MAC addresses to make forwarding decisions. It builds a MAC address table by learning source MAC addresses from incoming frames and then forwards frames only to the specific port associated with the destination MAC address, reducing collision domains and improving network efficiency.

Answer

Hub

Answer

Router

Answer

Firewall

Question 5

Which of the following best describes the purpose of the TCP three-way handshake?

Accepted Answer

To establish a reliable connection between two hosts. The TCP three-way handshake is the process by which two hosts synchronize sequence numbers and establish a reliable connection before data transfer begins. It involves the exchange of SYN, SYN-ACK, and ACK segments, ensuring both sides are ready to communicate and agree on initial sequence numbers (ISNs) as defined in RFC 793.

Answer

To terminate a connection gracefully

Answer

To resolve an IP address to a MAC address

Answer

To encrypt data between two devices

Question 6

Drag and drop the steps in the DHCP lease process (DORA) into the correct order.

Accepted Answer

Discover, Offer, Request, Acknowledge. The DHCP lease process follows the DORA sequence: Discover, Offer, Request, Acknowledge. The client initiates by broadcasting a Discover packet. DHCP servers reply with an Offer containing an IP address. The client then sends a Request to formally accept one offer. Finally, the server sends an Acknowledge to confirm the lease and provide additional configuration parameters. This order ensures proper negotiation and avoids conflicts.

Answer

Discover, Request, Offer, Acknowledge

Answer

Offer, Discover, Request, Acknowledge

Answer

Discover, Offer, Acknowledge, Request

Question 7

A network administrator needs to monitor network devices using SNMP. The security policy requires that both authentication and data encryption must be enforced for all SNMP operations. Which SNMPv3 security level should be configured?

Accepted Answer

authPriv. The authPriv security level is correct because it enforces both authentication (via HMAC-MD5 or HMAC-SHA) and data encryption (via DES or AES) for SNMPv3 operations, satisfying the security policy requirement. SNMPv3 defines three security levels: noAuthNoPriv, authNoPriv, and authPriv, with authPriv being the only one that provides both authentication and encryption.

Answer

noAuthNoPriv

Answer

authNoPriv

Answer

noAuthPriv

Question 8

A network technician needs to connect two switches to support multiple VLANs between them. The technician wants to use a single link to carry traffic for all VLANs. Which protocol should be used to tag frames with VLAN information?

Accepted Answer

802.1Q. 802.1Q is the IEEE standard for VLAN tagging, which inserts a 4-byte tag into the Ethernet frame header to identify the VLAN membership of the frame. This allows a single trunk link between two switches to carry traffic for multiple VLANs by tagging each frame with its corresponding VLAN ID (1-4094).

Answer

802.1X

Answer

802.11

Answer

802.3

Question 9

A company wants to ensure that only devices with known MAC addresses can connect to the guest Wi-Fi network. Which security feature should be configured on the wireless controller?

Accepted Answer

MAC filtering. MAC filtering allows the wireless controller to maintain an allowlist of known MAC addresses, so only devices with those addresses can associate with the guest SSID. This directly meets the requirement to restrict access based on MAC addresses without requiring authentication credentials from users.

Answer

WPA2-Enterprise

Answer

802.1X

Answer

WPA3-Personal

Question 10

A network administrator needs to monitor the health and performance of network devices and receive alerts when link failures occur. Which of the following protocols should be implemented?

Accepted Answer

SNMP. SNMP (Simple Network Management Protocol) is the correct choice because it is specifically designed to monitor and manage network devices, collect performance metrics, and send traps or notifications when events like link failures occur. SNMP agents on devices report status to a management system, which can generate alerts based on thresholds or trap messages (e.g., linkDown traps per RFC 3418).

Answer

SMTP

Answer

SSH

Answer

TFTP

Question 11

Match each OSI layer to its description.

Accepted Answer

Physical Layer: Transmits raw bits over a physical medium.. The correct matches are: Physical layer transmits raw bits, Network layer routes with logical addressing, and Application layer supports user applications. Common confusions involve swapping the roles of Data Link and Transport layers.

Answer

Data Link Layer: Provides end-to-end communication and error recovery.

Answer

Transport Layer: Provides reliable node-to-node communication.

Question 12

A network administrator configures a router-on-a-stick to route traffic between VLAN 10 and VLAN 20. Users in each VLAN can communicate within their own VLAN but cannot reach devices in the other VLAN. The router has subinterfaces configured, and the switch port connected to the router is configured as an access port in VLAN 1. What is the most likely cause of the inter-VLAN connectivity failure?

Accepted Answer

The switch port connected to the router is not configured as a trunk.. The router-on-a-stick design requires the switch port connecting to the router to be configured as a trunk port. This allows the switch to forward frames from multiple VLANs (VLAN 10 and VLAN 20) to the router's subinterfaces, each tagged with the appropriate 802.1Q VLAN ID. When the port is set as an access port in VLAN 1, it only accepts untagged frames from VLAN 1, so the router's subinterfaces for VLAN 10 and VLAN 20 never receive traffic, breaking inter-VLAN routing.

Answer

The router's subinterfaces are not configured with IP addresses.

Answer

The VLANs are not created on the switch.

Answer

The router's default route is missing.

Question 13

A user at a branch office reports that they cannot connect to a file server at the main office. The branch office connects to the main office via a site-to-site VPN, and the VPN tunnel shows as active. The user can ping the main office's default gateway but not the file server. Which of the following should the technician check NEXT?

Accepted Answer

A) Check the routing tables on the branch router. The VPN tunnel is active and the user can ping the main office's default gateway, which confirms that Layer 3 connectivity exists across the tunnel. However, the file server is unreachable, indicating that the traffic destined for the file server's subnet is not being forwarded correctly. The next logical step is to check the routing tables on the branch router to ensure there is a specific route (or a default route) pointing to the VPN tunnel interface for the file server's network. Without this route, the branch router may be dropping the packets or sending them out the wrong interface.

Answer

B) Check the DNS resolution for the file server

Answer

C) Check the VPN encryption settings

Answer

D) Check the file server's antivirus software

Question 14

A network administrator is deploying a wireless network in a warehouse environment with many metal racks. Clients using 802.11ac report strong signal strength but very low throughput. What is the most likely cause?

Accepted Answer

Multipath interference caused by signal reflections off metal surfaces. In a warehouse with many metal racks, 802.11ac signals reflect off the metal surfaces, creating multiple signal paths that arrive at the receiver at slightly different times. This multipath interference causes phase cancellation and intersymbol interference, which degrades the signal-to-noise ratio and forces the use of lower modulation and coding schemes (MCS), drastically reducing throughput despite strong RSSI.

Answer

Co-channel interference from neighboring access points

Answer

The encryption method is set to WEP, which limits throughput

Answer

Too many clients are connected to the same access point

Question 15

A network technician is explaining the function of a default gateway to a junior technician. Which of the following best describes the purpose of a default gateway?

Accepted Answer

It routes traffic from the local network to external networks.. The default gateway is a router or Layer 3 device that serves as the next-hop destination for packets destined to IP addresses outside the local subnet. When a host determines that the destination IP is not on the same network, it forwards the frame to the default gateway's MAC address, which then routes the packet toward the external network. This is defined in RFC 1122 and is essential for any host that needs to communicate beyond its directly connected segment.

Answer

It connects two different VLANs.

Answer

It provides DHCP services to the local network.

Answer

It translates private IP addresses to public IP addresses.