N10-009 Practice Test 36 — 15 Questions

Question 1

A company wants to ensure that only authorized employee computers can connect to the wired network. Each computer must be authenticated before it is granted access to the network. Which technology is designed to provide this port-based authentication?

Accepted Answer

802.1X. 802.1X is the IEEE standard for port-based Network Access Control (NAC). It uses the Extensible Authentication Protocol (EAP) over LAN (EAPoL) to authenticate a device at the switch port before granting full network access. Only after successful authentication does the switch open the port, ensuring that unauthorized computers cannot connect.

Answer

WPA2

Answer

MAC filtering

Answer

VPN

Question 2

A network engineer is designing an OSPF network for a large enterprise. To reduce the size of routing tables and limit the propagation of external routes, the engineer wants to use a special area that blocks Type 5 LSAs but still allows inter-area routes via a default route. Which type of OSPF area should be configured?

Accepted Answer

Stub area. A stub area blocks Type 5 LSAs (external routes) from entering the area, forcing the area border router (ABR) to inject a default route (0.0.0.0/0) for reaching external destinations. This reduces the routing table size while still allowing inter-area routes (Type 3 LSAs) to propagate, exactly matching the requirement.

Answer

Backbone area 0

Answer

Standard area

Answer

Totally stubby area

Question 3

A network administrator has configured SNMPv3 on a router to send traps to a central management server. The administrator notices that no traps are being received. The management server is reachable via ping from the router. Which configuration step is most likely missing?

Accepted Answer

Configure SNMPv3 authentication and privacy credentials on both the router and the server. SNMPv3 requires authentication and encryption (privacy) to be configured on both the router and the management server. Without matching credentials, the server will reject or ignore the traps, even if the network path is reachable. This is the most likely missing step because SNMPv3 does not use community strings and relies on security models (authNoPriv, authPriv, or noAuthNoPriv) that must be consistent between endpoints.

Answer

Configure the SNMP community string on the router

Answer

Set the SNMP trap destination IP address on the router

Answer

Ensure the SNMP agent is enabled on the router

Question 4

A network administrator is designing a small office network with 40 workstations. The design must ensure that a single cable failure only affects the connected workstation. Which logical topology should the administrator implement?

Accepted Answer

Star. A star topology connects each workstation directly to a central switch or hub, so a cable failure only affects the single connected workstation, not the rest of the network. This meets the requirement for fault isolation at the workstation level, which is the core design goal in a small office with 40 devices.

Answer

Ring

Answer

Bus

Answer

Mesh

Question 5

A network administrator needs to ensure that all changes to network devices are properly reviewed, approved, and tracked. Which process should the administrator implement?

Accepted Answer

Change management. Change management is the formal process for requesting, reviewing, approving, implementing, and documenting changes to network devices. It ensures that all modifications are authorized, tracked, and have a rollback plan, which directly meets the requirement for review, approval, and tracking.

Answer

Incident management

Answer

Problem management

Answer

Asset management

Question 6

A network engineer is installing a WLAN in a warehouse with many metal shelves and racks. During a site survey, the engineer notices significant signal degradation in certain areas. Which wireless propagation phenomenon is most likely causing the issue?

Accepted Answer

Reflection. In a warehouse with many metal shelves and racks, the primary cause of signal degradation is reflection. Metal surfaces act as RF reflectors, causing the wireless signal to bounce off them, which leads to multipath interference and dead zones where the signal cancels out or becomes too weak to be usable. This is a common issue in environments with high metal density, as the reflected waves interfere with the direct path signal.

Answer

Refraction

Answer

Diffraction

Answer

Absorption

Question 7

A network engineer needs to segment a single physical switch into multiple broadcast domains to improve security and reduce traffic. Which technology should be implemented?

Accepted Answer

Virtual LAN (VLAN). A VLAN (Virtual LAN) segments a physical switch into multiple isolated broadcast domains at Layer 2. By assigning ports to different VLANs, broadcast traffic is confined to each VLAN, improving security and reducing unnecessary traffic. This directly meets the requirement without requiring additional hardware.

Answer

Spanning Tree Protocol (STP)

Answer

VLAN Trunking Protocol (VTP)

Answer

Access Control List (ACL)

Question 8

A network technician is troubleshooting an intermittent link between two switches connected via single-mode fiber. The interface logs show frequent 'link up / link down' events, sometimes several times per hour. The technician has verified that the SFPs are compatible and the fiber cable is within distance specifications. Which of the following is the most likely cause of the issue?

Accepted Answer

Dirty or contaminated fiber connectors. Intermittent link flaps on single-mode fiber, despite compatible SFPs and correct distance, are most often caused by dirty or contaminated fiber connectors. Even microscopic dust or oil on the end face can scatter light, causing signal loss that triggers the switch's optical receiver to lose sync and flap the link. This matches the symptom of frequent 'link up / link down' events without any configuration mismatch.

Answer

Electromagnetic interference (EMI) from nearby power cables

Answer

Mismatched VLAN configurations on the switches

Answer

Duplex mismatch between the two switch ports

Question 9

A network technician needs to retrieve the operating system and uptime information from a router for inventory purposes. Which protocol is specifically designed for network management and monitoring?

Accepted Answer

SNMP. SNMP (Simple Network Management Protocol) is the standard protocol specifically designed for network management and monitoring. It allows a network management station to query managed devices (like routers) for system information, including operating system version and uptime, via OIDs (Object Identifiers) in the MIB (Management Information Base).

Answer

SMTP

Answer

HTTP

Answer

FTP

Question 10

A security analyst discovers that an unauthorized device is sending forged ARP replies, causing other devices to map the default gateway IP address to the attacker's MAC address. Which security feature should be implemented on the switches to prevent this attack?

Accepted Answer

Dynamic ARP Inspection. Dynamic ARP Inspection (DAI) is the correct choice because it validates ARP packets on a per-port basis, ensuring that only legitimate ARP replies with correct IP-to-MAC bindings are forwarded. DAI uses a DHCP snooping binding table (or static ARP ACLs) to intercept and verify ARP packets, dropping forged replies that attempt to poison the ARP cache of other devices.

Answer

Port security

Answer

DHCP snooping

Answer

BPDU guard

Question 11

A security analyst notices that the company's web server is receiving a high volume of TCP SYN packets from a single source IP address, but the server is not completing the three-way handshake. Which type of attack is most likely occurring?

Accepted Answer

A) SYN flood. A SYN flood attack exploits the TCP three-way handshake by sending a high volume of SYN packets from a spoofed or single source IP without completing the handshake. The server allocates resources for each half-open connection, eventually exhausting its connection table and denying service to legitimate users. This matches the scenario where the server receives many SYN packets but never completes the handshake.

Answer

B) Smurf attack

Answer

C) Ping of death

Answer

D) ARP poisoning

Question 12

A user's laptop frequently disconnects from the Wi-Fi network when they move to the conference room. Other devices in the conference room maintain stable connections. The laptop shows a strong signal in the conference room. What is the most likely cause?

Accepted Answer

Laptop's wireless adapter driver is outdated or faulty. The laptop disconnects only when moving to the conference room, while other devices remain stable, ruling out environmental issues. A strong signal but frequent disconnects points to a client-side problem, most commonly an outdated or faulty wireless adapter driver that fails to handle roaming or power-save transitions properly.

Answer

AP channel is congested

Answer

Laptop is using the 5 GHz band while the AP uses 2.4 GHz

Answer

Interference from microwave ovens

Question 13

A user reports that they can access the internet but cannot access the company's internal web application at https://intranet.company.local. The technician can ping the server's IP address (192.168.10.50) successfully from the user's workstation. However, when the technician runs 'nslookup intranet.company.local', it returns 'Non-existent domain'. What is the most likely cause?

Accepted Answer

The client's DNS server does not have a record for the internal domain.. The user can access the internet and ping the server's IP address, which confirms Layer 3 connectivity and that the web server is reachable. However, 'nslookup intranet.company.local' returns 'Non-existent domain', indicating that the DNS server used by the client does not have an A or CNAME record for that internal hostname. Since the browser relies on DNS resolution to translate the FQDN to an IP address, the failure to resolve the name prevents the web application from loading, even though the server itself is online and reachable.

Answer

The web server is not running on port 443.

Answer

A firewall is blocking traffic to the internal web server.

Answer

The hostname is misspelled in the browser.

Question 14

A user reports that they cannot access the internet. The technician tests connectivity: pinging the default gateway succeeds, but pinging a public IP address like 8.8.8.8 fails. Firewall logs show outbound ICMP to 8.8.8.8 is permitted. What is the most likely cause?

Accepted Answer

Missing default route on the router. The user can ping the default gateway (local connectivity) but cannot ping a public IP like 8.8.8.8. This indicates that the workstation has a valid route to its local subnet, but the router lacks a default route (0.0.0.0/0) to forward traffic to the internet. Firewall logs confirm outbound ICMP is permitted, so the issue is at Layer 3 routing, not filtering.

Answer

Incorrect DNS configuration on the workstation

Answer

Duplicate IP address on the local network

Answer

Proxy server configuration is required

Question 15

An attacker is eavesdropping on network traffic to capture sensitive data sent over an unencrypted HTTP connection. Which technology should be implemented to protect data in transit between clients and web servers?

Accepted Answer

SSL/TLS. SSL/TLS (Secure Sockets Layer/Transport Layer Security) operates at the application layer to encrypt HTTP traffic, creating HTTPS. This ensures that data transmitted between clients and web servers is encrypted, preventing eavesdroppers from reading sensitive information like passwords or credit card numbers. TLS is the standard protocol for securing HTTP communications, as defined in RFC 8446.

Answer

IPSec

Answer

SSH

Answer

SNMPv3