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Question 1

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A client STA must choose the best AP for connectivity. As part of the evaluation, it must verify compatible data rates. What can the client STA use to verify that an AP supports the same data rates

Question 2

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In an 802.11n (H T) 2.4 GHz BSS, what prevents each station from using all the airtime when other client stations are actively communicating in the same BSS?

Question 3

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What frame type is used to reserve the wireless medium for the transmission of high data rate frames that may not be understood by all clients connected to the BSS?

Question 4

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You are reporting on the RF environment in your facility. The manager asks you to describe the noise floor noted in the report. Which of the following is the best explanation?

Question 5

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Lynne runs a small hotel, and as a value added service for his customers he has implemented a Wi-Fi hot-spot. Lynne has read news articles about how hackers wait at hot-spots trying to take advantag

Question 6

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You have been tasked with creating a wireless link between two buildings on a single campus. The link must support at least 150 Mbps data rates. What kind of WLAN technology role should you deploy?

Question 7

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When implementing PoE, what role is played by a switch?

Question 8

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A dual-band 802.11ac AP must be powered by PoE. As a class 4 device, what power level should be received at the AP?

Question 9

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A WLAN is implemented using wireless controllers. The APs must locate the controllers when powered on and connected to the network. Which one of the following methods is commonly used to locate the

Question 10

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You are implementing a multi-AP WLAN and fast secure roaming is essential. Which one of the following methods is an IEEE 802.11 standard method for fast roaming?

Question 63 - CWNA-109 discussion

What feature of 802.1 lax (HE) may impact design decisions related to AP placement and the spacing between same-channel BSS cells (3SAs) because it is designed to reduce overlapping BSS contention?

TWT

BSS Color

uplink MU-MIMO

6 GHz band support

Suggested answer: B

Explanation:

In the 802.11ax (High Efficiency, HE) amendment, one of the key features introduced is BSS (Basic Service Set) Coloring. This feature is designed to mitigate issues arising from overlapping BSSs (OBSS), which can lead to contention and interference in dense wireless environments. BSS Coloring works by:

Assigning a 'color' (a small number) to each BSS: This helps devices differentiate between frames from their own BSS and those from neighboring BSSs.

Reducing Inter-BSS Interference: Devices can ignore frames from different BSSs (with a different 'color') under certain conditions, reducing the impact of OBSS interference.

Improving Spatial Reuse: By distinguishing between transmissions from different BSSs, devices can make more informed decisions about when to transmit, improving the efficiency of spatial reuse and reducing unnecessary contention.

This feature directly impacts design decisions related to AP placement and the spacing between same-channel BSS cells, as it allows for closer placement of APs on the same channel without significantly increasing interference, thus improving overall network capacity and efficiency.

The other options, while features of 802.11ax, do not directly pertain to reducing overlapping BSS contention in the same manner:

TWT (Target Wake Time) optimizes device sleep schedules to conserve power.

Uplink MU-MIMO enhances uplink data transmission capabilities but doesn't specifically address OBSS contention.

6 GHz Band Support introduces new spectrum for Wi-Fi use but is not a feature aimed at reducing OBSS contention within the 802.11ax framework.

Therefore, the correct answer is B, BSS Color.

IEEE 802.11ax-2021: Enhancements for High Efficiency WLAN.

CWNA Certified Wireless Network Administrator Official Study Guide: Exam CWNA-109, by David D. Coleman and David A. Westcott.

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asked 16/09/2024

Adam Burdett

31 questions

Your answer: A B C D

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