CWNA: Certified Wireless Network Administrator v109 — Question 3

You have implemented an 802.11ax WLAN for a customer. All APs are four stream HE APs. The customer states that it is essential that most of the clients can use the OFDMA modulation scheme. What do you tell the customer?

Answer options

• A. All 5 GHz PHYs use OFDM modulation, so you will achieve OFDMA everywhere in 5 GHz
• B. If the devices support 802.11ac, they can be updated to support OFDMA through driver upgrades
• C. OFDMA is an optional feature of 802.11ax and most APs don’t even support it
• D. The clients that must support OFDMA must be using an 802.11ax or Wi-Fi 6/6E chipset

Correct answer: A

Explanation

The correct answer is A because all 5 GHz PHYs in 802.11ax utilize OFDM modulation, enabling OFDMA across the 5 GHz band. Option B is incorrect as 802.11ac devices do not support OFDMA, even with driver updates. Option C is misleading since while OFDMA is optional, the specific APs mentioned support it. Option D is also incorrect because while clients need to support 802.11ax for OFDMA, the question focuses on the APs being able to provide OFDMA, which they can.