2.4 – Compare and contrast wireless networking protocols

Question 1

Which of the following would a company most likely use for authentication to a
server room?
 ❍ A. 802.11ac
 ❍ B. 802.15-4
 ❍ C. RFID
 ❍ D. Z-Wave
 ❍ E. MIMO

Answer 1

C. RFID (radio-frequency identification) is commonly used for access to areas of
a building such as a server room. It is often implemented as a proximity-based ID
card or badge. The other options are not usually associated with authentication.
802.11ac is a WLAN (Wi-Fi) standard that runs on 5 GHz and can provide 1 Gbps
of data transfer. 802.15-4 is the IEEE standard for Zigbee. Z-Wave, like Zigbee, is
a home automation and wireless sensor control technology. MIMO (multiple-input
and multiple-output) is a multiple propagation technology used to increase data
transfer in 802.11n and 802.11ac wireless networks.

Question 2

Which standard can attain a data transfer rate of 1 Gbps over a wireless
connection?
 ❍ A. 802.11a
 ❍ B. 802.11b
 ❍ C. 802.11g
 ❍ D. 802.11ac
 ❍ E. 802.3ab

Answer 2

D. 802.11ac can attain speeds in excess of 1 Gbps over wireless. 802.11a and g have a typical maximum of 54 Mbps. 802.11b (rarely used today) has a maximum of 11 Mbps. 802.3ab is the IEEE specification for 1-Gbps transfer over twisted-pair cables—it is wired, not wireless. By the way, this is also known as
1000BASE-T

Question 3

Which of the following is often broken down into groups of channels including
1-5, 6–10, and 11?
 ❍ A. 802.11ac
 ❍ B. 2.4 GHz
 ❍ C. 5 GHz
 ❍ D. 802.11a

Answer 3

B. In the United States, the 2.4-GHz frequency range is broken down into three
categories: Channel 1–5, 6–10, and 11. By placing separate wireless networks
on separate distant channels (such as 1 and 11), you can avoid overlapping and
interference. 802.11ac and 802.11a are standards, not frequencies. 5 GHz uses
channels such as 36, 40, 149, 153, and so on.