ACMA Wireless Fundamentals 5

Question 1

What is the primary advantage of using 5 GHz over 2.4 GHz for wireless deployments?

Accepted Answer

More available channels and less interference

Answer

The 5 GHz band offers up to 25 non-overlapping 20 MHz channels in the US and experiences far less interference from consumer devices.

Question 2

In an 802.11 infrastructure BSS, which device is responsible for coordinating access to the wireless medium?

Accepted Answer

The Access Point (AP)

Answer

In infrastructure mode, the AP coordinates medium access and acts as the central point for all client communications.

Question 3

What technology introduced in 802.11ac Wave 2 allows an AP to transmit to multiple clients simultaneously using separate spatial streams?

Accepted Answer

MU-MIMO

Answer

MU-MIMO (Multi-User MIMO) was introduced in 802.11ac Wave 2, allowing an AP to transmit to multiple clients simultaneously in the downlink.

Question 4

Which 802.11 feature reduces power consumption by allowing a client to enter a sleep state and buffer frames at the AP?

Accepted Answer

Target Wake Time (TWT)

Answer

Target Wake Time (TWT), introduced in 802.11ax/Wi-Fi 6, allows clients and APs to negotiate specific times for data exchange, dramatically reducing power consumption.

Question 5

What is a co-channel interference (CCI) in Wi-Fi, and why does it degrade performance?

Accepted Answer

Interference from multiple APs sharing the same channel within range

Answer

CCI occurs when multiple APs on the same channel overlap, forcing devices to compete for airtime and increasing contention and retransmissions.

(ACMA) Aruba Certified Mobility Associate Practice Test

(ACMA) Aruba Certified Mobility Associate Practice Test

ACMA Wireless Fundamentals 5