ACMA Wireless Fundamentals 2

Question 1

Which IEEE 802.11 amendment introduced OFDMA as a key feature for improved multi-user efficiency?

Accepted Answer

802.11ax

Answer

802.11ax (Wi-Fi 6) introduced OFDMA, which divides channels into resource units to serve multiple clients simultaneously.

Question 2

What is the primary purpose of a CSMA/CA mechanism in 802.11 wireless networks?

Accepted Answer

To avoid collisions before transmitting

Answer

CSMA/CA (Carrier Sense Multiple Access with Collision Avoidance) listens for channel activity and uses random backoff timers to reduce collisions.

Question 3

Which wireless band typically provides greater range but lower throughput due to its lower frequency?

Accepted Answer

2.4 GHz

Answer

The 2.4 GHz band propagates farther through obstacles but offers fewer non-overlapping channels and lower maximum throughput than 5 GHz.

Question 4

What does EIRP stand for in the context of wireless networking?

Accepted Answer

Effective Isotropic Radiated Power

Answer

EIRP is the total radiated power combining transmit power and antenna gain, used by regulators to limit interference.

Question 5

In 802.11 networks, what is the function of the ACK (Acknowledgment) frame?

Accepted Answer

To confirm successful receipt of a unicast data frame

Answer

The receiving station sends an ACK frame after successfully receiving a unicast frame to confirm delivery.

(ACMA) Aruba Certified Mobility Associate Practice Test