ACMA Wireless Networking Fundamentals & Technologies 5

Question 1

What is co-channel interference (CCI) in wireless networking?

Accepted Answer

Interference between two APs operating on the same channel within range of each other

Answer

Co-channel interference occurs when two or more APs use the same channel and their coverage areas overlap, forcing clients to compete for the same medium.

Question 2

In 802.11 WMM (Wi-Fi Multimedia), which Access Category has the highest priority?

Accepted Answer

AC_VO (Voice)

Answer

AC_VO (Voice) has the highest QoS priority in WMM, using the shortest AIFSN and CWmin values to minimize latency for voice traffic.

Question 3

What is the effect of increasing the channel width from 20 MHz to 80 MHz in 802.11ac?

Accepted Answer

It reduces the number of non-overlapping channels and increases throughput

Answer

Wider channels carry more subcarriers and increase throughput, but consume more spectrum and reduce the number of available non-overlapping channels.

Question 4

Which physical layer characteristic determines the maximum theoretical data rate of an 802.11 link?

Accepted Answer

Channel width, modulation scheme, coding rate, and number of spatial streams

Answer

The PHY data rate is a product of channel width (subcarrier count), modulation and coding scheme (MCS), and the number of spatial streams used.

Question 5

What does the 802.11k standard enable in a wireless network?

Accepted Answer

Radio resource measurement and neighbor reporting to assist client roaming decisions

Answer

802.11k provides mechanisms for APs and clients to exchange radio resource measurements and neighbor AP lists, helping clients make better-informed roaming decisions.

(ACMA) Aruba Certified Mobility Associate Practice Test

(ACMA) Aruba Certified Mobility Associate Practice Test

ACMA Wireless Networking Fundamentals & Technologies 5