N10-009 Network Implementation Practice Test 2 — 15 Questions

Question 1

A network administrator has just connected a new access switch to the core switch via a trunk port. The administrator configured the trunk port on both switches with the same allowed VLAN list. However, hosts on VLAN 10 connected to the new access switch cannot communicate with hosts on VLAN 10 on the core switch. The trunk is operational and shows up/up. What is the most likely cause?

Choose an answer to begin — your selection is scored in the full session.

Accepted Answer

A) VLAN 10 has not been created on the new access switch. The most likely cause is that VLAN 10 has not been created on the new access switch. Even though the trunk port is up/up and the allowed VLAN list matches, a switch will not forward traffic for a VLAN that does not exist in its local VLAN database. Without the VLAN being created, the switch drops all frames tagged with VLAN 10, preventing communication between hosts on that VLAN across the trunk.

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B) Native VLAN mismatch on the trunk

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C) Trunk encapsulation mismatch (ISL vs 802.1Q)

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D) STP is blocking the VLAN 10 traffic on the trunk

Question 2

A company is deploying a new wireless network in a warehouse. The network administrator needs to ensure that clients can seamlessly roam between access points without losing connectivity. Which of the following should be configured?

Accepted Answer

A) Same SSID and security settings on all APs. Configuring the same SSID and security settings on all access points (APs) is essential for seamless roaming because clients use the SSID to identify the network and the security credentials to authenticate. When a client moves between APs, it can re-associate without needing to re-authenticate or discover a new network, provided the SSID and security parameters (e.g., PSK or 802.1X configuration) are identical. This ensures a smooth handoff and maintains connectivity during roaming.

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B) Different channels per AP to reduce interference

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C) WPA2-Enterprise with RADIUS authentication

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D) Mesh topology for AP interconnection

Question 3

A company is setting up a new branch office and needs to connect it to the main office over the internet using a secure VPN. The branch office has a dynamic public IP address. Which type of VPN should be configured?

Accepted Answer

Dynamic Multipoint VPN (DMVPN). C is correct because Dynamic Multipoint VPN (DMVPN) is designed to handle sites with dynamic public IP addresses, such as a branch office with a dynamically assigned IP. DMVPN uses mGRE (multipoint Generic Routing Encapsulation) and NHRP (Next Hop Resolution Protocol) to dynamically establish tunnels between spoke routers without requiring static IP configurations on each spoke, making it ideal for this scenario.

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Site-to-site IPsec VPN with static IPs

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Remote access VPN using SSL

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Policy-based VPN

Question 4

A company is implementing a wireless network and needs to support high-density client environments with minimal interference. Which IEEE 802.11 standard operates in the 5 GHz band and provides the highest throughput among the options?

Accepted Answer

802.11ac. 802.11ac (Wi-Fi 5) operates exclusively in the 5 GHz band and supports up to 8 spatial streams, 256-QAM modulation, and channel bonding up to 160 MHz, yielding theoretical throughput exceeding 6.9 Gbps. This makes it the highest-throughput option among the listed standards for high-density environments with minimal interference, as the 5 GHz band offers more non-overlapping channels and less co-channel contention than 2.4 GHz.

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802.11n

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802.11g

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802.11b

Question 5

A company is deploying a wireless network that must support both 2.4 GHz and 5 GHz frequency bands. Which IEEE 802.11 standard supports both bands and is backward compatible with older devices?

Accepted Answer

C) 802.11n. 802.11n (Wi-Fi 4) is the correct answer because it was the first standard to natively support both 2.4 GHz and 5 GHz bands simultaneously, using MIMO (Multiple Input Multiple Output) technology. It also maintains backward compatibility with older 802.11a/b/g devices through mandatory support for legacy modulation schemes (DSSS/CCK for 2.4 GHz and OFDM for 5 GHz).

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A) 802.11b

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B) 802.11g

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D) 802.11ac

Question 6

A network engineer has configured an IPsec site-to-site VPN between two offices. The tunnel is established and shows as active. However, users at the branch office (10.0.1.0/24) cannot reach servers at the main office (192.168.1.0/24). Both routers have the correct VPN policies and firewall rules permitting IPsec traffic. What should the engineer check next?

Accepted Answer

B) That the routing tables on both routers include routes to the remote subnet. The tunnel being active means Phase 1 and Phase 2 of IPsec are established, but traffic still cannot flow because the routers lack routes to the remote subnets. Without a route for 10.0.1.0/24 on the main office router (or 192.168.1.0/24 on the branch router), packets will be dropped or sent out the wrong interface, even though the VPN policy and firewall rules are correct. The engineer must verify that static routes or a dynamic routing protocol (e.g., OSPF over the tunnel) are in place to direct traffic into the IPsec tunnel interface.

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A) That the DNS server addresses are correctly configured

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C) That the MTU size is set to 1500 on both ends

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D) That the SSID is correctly configured on the access points

Question 7

A network engineer has successfully established an IPsec site-to-site VPN tunnel between a branch office (10.0.1.0/24) and the main office (192.168.1.0/24). The tunnel status shows as active, and both sides can ping each other's tunnel interface IP addresses. However, users at the branch office cannot ping the main office server at 192.168.1.10, and the main office cannot ping the branch office server at 10.0.1.10. The firewall rules on both sides permit IPsec traffic and all internal traffic. What should the engineer check NEXT?

Accepted Answer

Verify routing entries on both routers to ensure the remote internal subnets are reachable via the tunnel.. The tunnel is active and both sides can ping each other's tunnel interface IPs, confirming that IPsec phase 1 and phase 2 are established and the tunnel itself is functional. However, users cannot reach the remote internal subnets (10.0.1.0/24 and 192.168.1.0/24), which indicates a routing problem: the routers likely lack routes for those remote subnets pointing to the tunnel interface. Without proper routing entries, traffic destined for the remote LAN is sent out the wrong interface or dropped, even though the tunnel is up.

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Check the IPsec security associations for encryption algorithm mismatch.

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Disable the firewall on the internal interfaces temporarily.

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Regenerate the pre-shared key on both sides.

Question 8

A network administrator is connecting two switches and wants to increase the bandwidth between them while also providing redundancy in case one link fails. Which technology should be configured on the switch ports?

Accepted Answer

Link Aggregation Control Protocol (LACP). Link Aggregation Control Protocol (LACP) allows multiple physical links between two switches to be combined into a single logical link, increasing aggregate bandwidth and providing redundancy: if one physical link fails, traffic continues over the remaining links. This directly meets the requirement for both higher bandwidth and link-level fault tolerance.

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Spanning Tree Protocol (STP)

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VLAN trunking (802.1Q)

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Power over Ethernet (PoE)

Question 9

A network administrator is configuring dynamic routing between two routers in the same organization. The routers must support VLSM, converge quickly, and use a metric that is based on bandwidth and delay. Which routing protocol should be configured?

Accepted Answer

EIGRP. C is correct because EIGRP is a Cisco-proprietary hybrid routing protocol that supports Variable-Length Subnet Masking (VLSM), converges rapidly using the Diffusing Update Algorithm (DUAL), and uses a composite metric that by default includes bandwidth and delay. This makes it ideal for the scenario where both VLSM support and fast convergence are required with a metric based on bandwidth and delay.

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RIP

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OSPF

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BGP

Question 10

A company is deploying a new wireless network for a small office. The network will consist of three access points. The IT manager wants the APs to automatically coordinate radio frequency settings and client roaming without a dedicated controller. Which technology should be implemented?

Accepted Answer

Cloud-managed access points. Cloud-managed access points (APs) are the correct choice because they can automatically coordinate radio frequency (RF) settings and client roaming without a dedicated on-premises controller. The cloud-based management platform handles channel selection, power adjustment, and fast roaming (e.g., 802.11r/k/v) by communicating with each AP over the internet, making it ideal for a small office with only three APs.

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Mesh network

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Controller-based wireless

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Standalone APs

Question 11

A company is extending its network to a new building located 200 meters away. The link must support 1 Gbps speeds. Which cabling type should be used?

Accepted Answer

Single-mode fiber. Single-mode fiber (SMF) is the correct choice because it supports 1 Gbps speeds over distances far exceeding 200 meters, typically up to 5 km or more using 1000BASE-LX optics. Copper cabling like Cat5e and Cat6 is limited to a maximum segment length of 100 meters for 1 Gbps (1000BASE-T), making them unsuitable for this 200-meter link.

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Cat5e

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Cat6

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Coaxial cable

Question 12

A company wants to deploy a wireless network in an office with high-density client requirements. Which 802.11 technology allows multiple antennas to transmit multiple spatial streams to increase throughput?

Accepted Answer

MIMO (Multiple-Input Multiple-Output). MIMO (Multiple-Input Multiple-Output) is the correct technology because it uses multiple antennas at both the transmitter and receiver to send and receive multiple independent spatial streams simultaneously. This spatial multiplexing directly increases data throughput without requiring additional bandwidth or higher modulation, making it ideal for high-density client environments.

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OFDM (Orthogonal Frequency Division Multiplexing)

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DSSS (Direct Sequence Spread Spectrum)

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CSMA/CA (Carrier Sense Multiple Access with Collision Avoidance)

Question 13

A network engineer is designing a subnet for a department that requires exactly 50 usable host addresses. Which subnet mask provides the minimum number of usable host addresses while still accommodating the requirement?

Accepted Answer

/26. A /26 subnet mask (255.255.255.192) provides 2^(32-26) = 64 total addresses, of which 62 are usable (subtracting network and broadcast addresses). This is the smallest subnet that meets the requirement of exactly 50 usable hosts, as /27 yields only 30 usable addresses and /28 yields only 14, while /25 provides 126 usable addresses, which is more than necessary.

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/27

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/28

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/25

Question 14

An organization uses OSPF as its interior gateway protocol in a multi-area design. After a core router failure, the network takes a long time to reconverge. Which technology can be implemented to improve convergence speed?

Accepted Answer

Implement Bidirectional Forwarding Detection (BFD). BFD provides sub-second failure detection by sending rapid, lightweight hello packets independently of OSPF's own hello mechanism. When a core router fails, BFD detects the link down in milliseconds and immediately signals OSPF to trigger reconvergence, drastically reducing the time OSPF would otherwise spend waiting for its own dead timer to expire.

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Use static routes instead of OSPF

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Increase OSPF hello and dead timers

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Configure all routers in a single OSPF area

Question 15

Two switches are connected via a trunk link configured with allowed VLANs 10, 20, and 30. Hosts on VLAN 20 can communicate across the trunk, but hosts on VLAN 30 cannot. Which of the following is the most likely cause?

Accepted Answer

D. The most likely cause is that VLAN 30 is only created on one switch. For a trunk to forward frames for a VLAN, that VLAN must exist (be created) on both switches. If VLAN 30 is only configured on one switch, the other switch will drop frames from VLAN 30, preventing communication. This explains why VLAN 20 works (exists on both) and VLAN 30 does not.

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A

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B

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C