CCNA Switching and Network Access — 10 Questions

Question 1

What is the main purpose of a VLAN on a switch?

Accepted Answer

To create a separate Layer 2 broadcast domain. A VLAN separates switch ports into distinct Layer 2 broadcast domains, improving segmentation and reducing unnecessary broadcast scope.

Answer

To encrypt user traffic on the switch

Answer

To increase the physical speed of switch ports

Answer

To replace the need for a default gateway

Question 2

Which statement best describes a lightweight access point in a controller-based WLAN?

Accepted Answer

It relies on a wireless LAN controller for centralized management and policy. In a controller-based wireless design, lightweight APs depend on a wireless LAN controller for centralized policy and management functions.

Answer

It performs all management and control functions independently

Answer

It can support only a single SSID

Answer

It cannot use PoE

Question 3

What is the purpose of Power over Ethernet (PoE)?

Accepted Answer

To deliver electrical power over Ethernet cabling. PoE allows network devices such as IP phones, wireless access points, and cameras to receive power through the same Ethernet cable used for data.

Answer

To encrypt Ethernet frames

Answer

To compress voice traffic on a LAN

Answer

To increase the maximum IPv4 MTU

Question 4

What does an access port do on a switch?

Accepted Answer

Connects to a single VLAN for endpoint traffic. An access port carries traffic for a single VLAN and sends frames untagged by default to end devices.

Answer

Carries multiple VLANs using 802.1Q tags

Answer

Disables spanning tree on the interface

Answer

Forwards only multicast traffic

Question 5

What is the main purpose of BPDU Guard on a PortFast-enabled access port?

Accepted Answer

To shut down an access port if a BPDU is received. BPDU Guard helps prevent accidental loops by shutting down a PortFast port if it receives a BPDU.

Answer

To elect the root bridge faster

Answer

To convert all trunks to routed ports

Answer

To allow BPDUs only from trusted access points

Question 6

Which statement best explains why trunks are needed between switches in a multi-VLAN environment?

Accepted Answer

They allow multiple VLANs to share one physical inter-switch link while preserving VLAN identity. Trunks are needed because they allow traffic from multiple VLANs to cross a single physical link between switches. In plain language, instead of using one cable per VLAN between switches, a trunk can carry many VLANs at once while preserving their identity through tagging. That makes the design much more scalable and practical in real networks.

Without trunking, only one VLAN’s traffic could normally use a simple access link at a time. In larger environments, that would quickly become messy and wasteful. CCNA questions often focus on this basic reason for trunks: efficient transport of multiple logically separate VLANs over one physical inter-switch connection.

Answer

They force every host port to become a routed port

Answer

They eliminate the need for VLAN tagging

Answer

They replace the need for IP addressing on switches

Question 7

Which statement best compares 2.4 GHz and 5 GHz Wi-Fi operation at a basic CCNA level?

Accepted Answer

2.4 GHz and 5 GHz have different tradeoffs in coverage characteristics and channel availability.. At a basic level, 2.4 GHz generally offers broader compatibility and longer reach characteristics, while 5 GHz commonly offers more channels and higher potential throughput with shorter effective reach in many environments. In practical terms, the key exam point is not memorizing every radio detail, but recognizing that the two bands have different tradeoffs.

This is a foundational wireless concept. The wrong answers usually pretend one band is universally superior in every respect, which is not how real design works.

Answer

5 GHz is used only for wired Ethernet uplinks.

Answer

2.4 GHz eliminates the need for SSIDs.

Answer

Both bands are actually ACL types.

Question 8

What is the primary role of a wireless LAN controller in a controller-based WLAN design?

Accepted Answer

To centralize management and control of access points and wireless policies. The primary role of a wireless LAN controller is to centralize the management and control of access points and wireless policies. In practical terms, instead of configuring every AP independently, the controller provides a single place to define SSIDs, security settings, RF-related policies, and operational behavior. This improves consistency and simplifies administration at scale.

The controller does not replace the access points physically. It coordinates them. That is the key distinction in controller-based WLAN design.

Answer

To replace all access points physically on the network

Answer

To act as the default gateway for all wired VLANs automatically

Answer

To convert every wireless frame into an OSPF packet

Question 9

Which statement best describes an SSID in a wireless LAN?

Accepted Answer

It is the name that identifies a wireless LAN to users and client devices.. An SSID is the network name that identifies a wireless LAN to users and client devices. In practical terms, it is the label a person sees when choosing between available Wi-Fi networks. It is not the security protocol itself and it is not the access point hardware. It is the identifier associated with the WLAN.

This is basic wireless vocabulary, but it matters because exam questions often put SSID next to AP, WPA2, and controller terms to see whether you can separate them.

Answer

It is the encryption algorithm used by the WLAN.

Answer

It is the physical antenna inside an access point.

Answer

It is the CAPWAP tunnel between the AP and controller.

Question 10

Which statement best describes why PortFast is usually appropriate on a user-facing access port but not on a normal switch-to-switch uplink?

Accepted Answer

Because PortFast is intended for edge ports and a normal uplink participates in the spanning-tree topology.. PortFast is appropriate on a user-facing access port because it speeds an edge port into forwarding without waiting through the normal STP transition. In practical terms, that improves startup behavior for hosts such as PCs and printers. On a normal switch-to-switch uplink, however, the link participates in spanning-tree topology decisions, so treating it like a simple edge port can introduce risk.

This is a standard access-layer design principle. PortFast is for endpoints, not ordinary infrastructure uplinks.

Answer

Because PortFast can be used only on routers.

Answer

Because switch-to-switch links cannot forward traffic.

Answer

Because PortFast automatically enables NAT on access ports.