Free CWNA-108 Exam Dumps Preview

Reference
https://www.networkcomputing.com/wireless-infrastructure/wifi-fast-roaming-simplified/1993108957

https://www.cisco.com/c/en/us/td/docs/wireless/controller/8-1/Enterprise-Mobility-8-1-Design-Guide/Enterprise_Mobility_8-1_Deployment_Guide/Chapter-11.pdf

Explanation: SAE (Simultaneous Authentication of Equals) is required when operating 802.11ax APs in the 6 GHz band using passphrase-based authentication. SAE is a secure and robust authentication method that is defined in the IEEE 802.11s amendment and is also known as WPA3-Personal or WPA3-SAE. SAE is based on a cryptographic technique called Dragonfly Key Exchange, which allows two parties to establish a shared secret key using a passphrase, without revealing the passphrase or the key to an eavesdropper or an attacker. SAE also provides forward secrecy, which means that if the passphrase or the key is compromised in the future, it does not affect the security of past communications. SAE is required when operating 802.11ax APs in the 6 GHz band using passphrase-based authentication because of the new regulations and standards that apply to this band. The 6 GHz band is a new frequency band that was opened for unlicensed use by the FCC and other regulatory bodies in 2020. The 6 GHz band offers more spectrum and less interference than the existing 2.4 GHz and 5 GHz bands, which can enable higher performance and efficiency for Wi-Fi devices. However, the 6 GHz band also has some restrictions and requirements that are different from the other bands, such as: The 6 GHz band is divided into two sub-bands: U-NII-5 (5925-6425 MHz) and U- NII-7 (6525-6875 MHz).
The U-NII-5 sub-band is subject to DFS (Dynamic Frequency Selection) rules, which require Wi-Fi devices to monitor and avoid using channels that are occupied by radar systems or other primary users. The U- NII-7 sub-band is not subject to DFS rules, but it has a lower maximum transmit power limit than the U-NII-

5 sub-band.
The Wi-Fi devices that operate in the 6 GHz band are called 6E devices, which stands for Extended Spectrum. 6E devices must support 802.11ax technology, which is also known as Wi-Fi 6 or High Efficiency (HE). 802.11ax is a new standard that improves the performance and efficiency of Wi-Fi networks by using features such as OFDMA (Orthogonal Frequency Division Multiple Access), MU-MIMO (Multi-User Multiple Input Multiple Output), BSS Coloring, TWT (Target Wake Time), and HE PHY and
MAC enhancements.
The 6E devices that operate in the 6 GHz band must also support WPA3 security, which is a new security protocol that replaces WPA2 and provides stronger encryption and authentication for Wi-Fi networks.
WPA3 has two modes: WPA3- Personal and WPA3-Enterprise. WPA3-Personal uses SAE as its authentication method, which requires a passphrase to establish a secure connection between two devices. WPA3-Enterprise uses EAP (Extensible Authentication Protocol) as its authentication method, which requires a certificate or a credential to authenticate with a server. Therefore, SAE is required when operating 802.11ax APs in the 6 GHz band using passphrase-based authentication because it is part of WPA3-Personal security, which is mandatory for 6E devices in this band.
References:
, Chapter 3, page
120
, Section 3.2 9of30

References:
https://books.google.com.pk/books?id=uA68E68OqQgC&pg=PA235&lpg=PA235&dq=impedance+mismatch+in+the+RF+cables+and+connectors+cause&source=bl&ots=WEynkTBqO1&sig=-Hm_d26REw_UrVZtz20xErL-4Rg&hl=en&sa=X&ved=0ahUKEwj5rvW0j57ZAhVMzqQKHeCGB0kQ6AEISDAF#v=onepage&q=impedance%20mismatch%20in%20the%20RF%20cables%20and%20connectors%20cause&f=false

A POE device that requires 47 W of power should use the 802.3bt specification. This is because 802.3bt is the latest POE standard that supports up to 90 W of power delivery over four pairs of wires in an Ethernet cable. The previous POE standards, such as 802.3af and 802.3at, only support up to 15.4 W and 30 W of power delivery over two pairs of wires in an Ethernet cable, respectively. Therefore, they are not sufficient for powering a device that requires 47 W of power. The 802.11at specification does not exist; it is a typo or
confusion with the 802.3at specification.
References:
CWNA-109 Study Guide, Chapter 8: Wireless LAN Access Points, page 2431

A VoIP phone is least likely to be a POE PSE of the devices listed. POE stands for Power over Ethernet, which is a technology that allows devices to receive both power and data over a single Ethernet cable. A POE PSE stands for Power Sourcing Equipment, which is a device that provides power to other devices over Ethernet. A POE PD stands for Powered Device, which is a device that receives power from a PSE over Ethernet. A midspan multi-port injector, a switch, and a midspan injector are examples of POE PSEs, as they can supply power to multiple devices over Ethernet cables. A VoIP phone is an example of a POE PD, as it can receive power from a PSE over an Ethernet cable. However, some VoIP phones can also act as POE PSEs for other devices, such as IP cameras or wireless access points, but this is not very common.
References:
CWNA-109 Study Guide, Chapter 8: Wireless LAN Access Points, page 2411

The clients are 802.11n devices. 802.11n devices can only support a maximum of four spatial streams, and the maximum data rate for a single spatial stream is 150 Mbps. Therefore, if most clients are only achieving 150 Mbps, it means they are using only one spatial stream, which is typical for 802.11n devices.
To achieve higher data rates, the clients would need to support more spatial streams, which is possible with 802.11ax devices 12.
The other options are not correct because they do not explain why most clients are only achieving 150
Mbps. Option B is incorrect because two stream 802.11ax clients can achieve data rates of up to 574
Mbps in a 20 MHz channel 1. Option C is incorrect because contention caused by an overlapping BSS would affect all clients, not just most of them, and it would also reduce the throughput, not the data rate.
Option D is incorrect because non-Wi-Fi interference in the channel would also affect all clients, not just most of them, and it would also cause errors and retransmissions, not lower data rates.
References:
1: CWNA-108 Official Study Guide, page 144
2: 802.11ax data rates

Reference
https://books.google.com.pk/books?id=0ZWLn57EdpsC&pg=PA142&lpg=PA142&dq=WLAN+security,
+what+authentication+method+always+creates+Layer+2+dynamic+encryption
+keys&source=bl&ots=CBgudPbaRh&sig=s7kLv2NeFqfjoBK6A_X- 9T2Nc0k&hl=en&sa=X&ved=0ahUKEwithMDooazZAhXMCuwKHfSNC-
kQ6AEIWTAH#v=onepage&q=WLAN%20security%2C%20what%20authentication%20method%

20always%20creates%20Layer%202%20dynamic%20encryption%20keys&f=false

Reference
http://setup-wireless.blogspot.com/2008/11/wireless-hidden-node.html