N10-009 Network Implementation Practice Test 5 — 15 Questions

Question 1

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?

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

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 2

A network administrator connects two switches with a trunk link that is configured to allow all VLANs. Workstations in VLAN 10 can communicate across the switches, but workstations in VLAN 20 cannot. Both VLANs are configured on the first switch. What is the most likely cause of the issue?

Accepted Answer

VLAN 20 is not created on the second switch.. VLAN 20 is configured on the first switch but not on the second switch. Even though the trunk link allows all VLANs, the second switch must have VLAN 20 created in its VLAN database for traffic to be forwarded. Without the VLAN existing on the second switch, frames tagged for VLAN 20 are dropped at the receiving switch because there is no corresponding VLAN interface or forwarding table entry.

Answer

The native VLAN is mismatched on the two switches.

Answer

The trunk uses ISL instead of 802.1Q.

Answer

The default gateway is missing for VLAN 20.

Question 3

An organization wants to deploy Wi-Fi in a large, open office space. They need high throughput and the ability to support many simultaneous clients, but they are budget-constrained. Which IEEE wireless standard should they choose?

Accepted Answer

802.11ac (Wi-Fi 5). 802.11ac (Wi-Fi 5) is the best choice for this scenario because it offers high throughput (up to 1.3 Gbps in the 5 GHz band) and supports MU-MIMO (downlink) for handling multiple clients simultaneously, all at a lower cost than 802.11ax (Wi-Fi 6). Since the organization is budget-constrained, 802.11ac provides a good balance of performance and affordability for a dense open office environment.

Answer

802.11ax (Wi-Fi 6)

Answer

802.11n (Wi-Fi 4)

Answer

802.11b (Wi-Fi 1)

Question 4

A network engineer is configuring a Link Aggregation Group (LAG) between two switches. Switch A is set to LACP active mode. Which mode should be configured on Switch B to form the LAG?

Accepted Answer

Passive. LACP active mode initiates negotiation by sending LACP packets, while passive mode responds to those packets without initiating. Since Switch A is set to active, Switch B must be in passive mode to successfully form a Link Aggregation Group (LAG). This combination allows the two switches to exchange LACP frames and agree on the aggregation parameters.

Answer

On

Answer

Static

Answer

Auto

Question 5

A network administrator is configuring OSPF on a router that has interfaces in only one area and does not perform route redistribution. Which OSPF router type best describes this router?

Accepted Answer

Internal router. An internal router has all its interfaces in a single OSPF area and does not perform route redistribution. Since the router's interfaces are confined to one area and it does not connect to other routing domains, it fits the definition of an internal router. This type of router maintains a single link-state database for that area and does not generate Type 3 or Type 5 LSAs.

Answer

Backbone router

Answer

Area Border Router (ABR)

Answer

Autonomous System Boundary Router (ASBR)

Question 6

A network administrator is configuring OSPF on routers in a multi-area network. The administrator wants to ensure that a router in area 1 does not learn external routes (Type 5 LSAs) injected by an ASBR in area 0, but it must still learn inter-area routes (Type 3 LSAs). The administrator wants to reduce the routing table size. Which OSPF area type should be configured for area 1?

Accepted Answer

Stub area. A stub area blocks Type 5 LSAs (external routes) from entering the area while still allowing Type 3 LSAs (inter-area routes). This meets the requirement of preventing external routes from the ASBR in area 0 from being learned by routers in area 1, while still permitting inter-area routing and reducing the routing table size.

Answer

Totally stubby area

Answer

Not-so-stubby-area (NSSA)

Answer

Normal area

Question 7

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 8

An OSPF network uses a multi-access segment with four routers. All router interfaces have the default OSPF priority of 1. Which router becomes the Designated Router (DR)?

Accepted Answer

The router with the highest router ID. In an OSPF multi-access network, the Designated Router (DR) is elected based on the highest OSPF priority value, with a tie-breaking mechanism using the highest Router ID. Since all routers have the default priority of 1, the router with the highest Router ID wins the DR election. This ensures a stable topology for reducing LSA flooding and adjacency overhead.

Answer

The router with the lowest IP address on the segment

Answer

The router with the highest bandwidth on the connecting interface

Answer

The router with the oldest uptime

Question 9

A company is deploying a wireless network in an office where employees move between floors. They want clients to authenticate once and maintain connectivity without re-authenticating when roaming between access points (APs). Which IEEE wireless standard provides this fast roaming capability?

Accepted Answer

802.11r. 802.11r, also known as Fast BSS Transition (FT), enables clients to roam between access points without re-authenticating at each new AP. It achieves this by using a cached Pairwise Master Key (PMK) and a four-way handshake that is optimized to reduce the time required for reassociation, typically completing in under 50 milliseconds. This ensures seamless connectivity for mobile users moving between floors.

Answer

802.11i

Answer

802.11e

Answer

802.11n

Question 10

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 11

A network engineer is deploying a wireless network using 802.11ac. To allow clients to roam between access points without re-authenticating to the authentication server, which IEEE standard should be implemented?

Accepted Answer

802.11r. 802.11r, also known as Fast BSS Transition (FT), enables clients to roam between access points using a cached Pairwise Master Key (PMK) without requiring a full 802.1X/EAP re-authentication with the RADIUS server. This reduces roaming latency to under 50 ms, which is critical for voice and video applications.

Answer

802.1X

Answer

802.11i

Answer

802.11e

Question 12

A network administrator needs to connect two switches to allow multiple VLANs to traverse the link. 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 multiple VLANs to traverse a single trunk link between switches, enabling inter-switch VLAN communication without requiring separate physical links per VLAN.

Answer

STP (Spanning Tree Protocol)

Answer

VTP (VLAN Trunking Protocol)

Answer

LACP (Link Aggregation Control Protocol)

Question 13

A network administrator needs to connect two switches located in separate buildings 150 meters apart. The connection must support 10 Gbps speeds. Which cabling type is most appropriate?

Accepted Answer

Multi-mode fiber optic. Multi-mode fiber optic (MMF) is the most appropriate choice because it supports 10 Gbps speeds over distances up to 300 meters (using OM3 or OM4 fiber) with cost-effective transceivers (e.g., 10GBASE-SR). The 150-meter distance exceeds the 100-meter maximum for twisted-pair copper cabling (Cat6a or Cat7) at 10 Gbps, making fiber the only viable option among the choices.

Answer

Cat6a twisted pair

Answer

Cat7 twisted pair

Answer

Single-mode fiber optic

Question 14

A network engineer needs to implement a wireless network in a large open-plan office with high client density. The network must provide the fastest possible speeds and efficient handling of many simultaneous connections. Which IEEE 802.11 standard should be used?

Accepted Answer

802.11ax. 802.11ax (Wi-Fi 6) is the correct choice because it introduces Orthogonal Frequency Division Multiple Access (OFDMA) and MU-MIMO (both uplink and downlink), which significantly improve spectral efficiency and capacity in high-density environments. It also supports 1024-QAM modulation for higher data rates, making it ideal for an open-plan office with many simultaneous connections.

Answer

802.11ac

Answer

802.11n

Answer

802.11r

Question 15

A network administrator needs to allow multiple VLANs to traverse a single link between two switches. Which configuration must be applied on the switch ports?

Accepted Answer

Trunk port. A trunk port is configured to carry traffic for multiple VLANs over a single link by tagging frames with IEEE 802.1Q VLAN identifiers. This allows the switch to distinguish which VLAN each frame belongs to, enabling inter-switch VLAN connectivity without requiring separate physical links per VLAN.

Answer

Access port

Answer

Hybrid port

Answer

Routed port