Shared Key Authentication is a security solution that was defined in the original 802.11 standard as an alternative to Open System Authentication, which does not provide any security at all. Shared Key Authentication uses WEP (Wired Equivalent Privacy) to encrypt and authenticate data frames between the client station and the AP. However, WEP has been proven to be extremely vulnerable to various attacks that can easily crack the encryption key and compromise the network security. Therefore, Shared Key Authentication is deprecated in the 802.11 standard and should never be used in any modern WLAN deployment . References: [CWNA-109 Study Guide], Chapter 10: Wireless LAN Security, page 401;
[CWNA-109Study Guide], Chapter 10: Wireless LAN Security, page 391; [Wikipedia], Wired Equivalent Privacy.

It is a channel that may require DFS when used is an important fact that should be considered about channel
128. Channel 128 is a 5 GHz frequency band 20 MHz channel that has a center frequency of 5.64 GHz.
Channel 128 is one of the channels that are 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. DFS is a feature that is defined in the IEEE 802.11h amendment and is mandated by some regulatory bodies, such as the FCC and the ETSI, to protect the licensed users of the 5 GHz band from interference by unlicensed Wi-Fi devices. DFS works by using a mechanism called channel availability check (CAC), which requires Wi-Fi devices to scan a channel for a certain period of time before using it. If a radar signal is detected during the CAC or while using the channel, the Wi-Fi devices must switch to another channel that is free from radar interference.
When configuring an access point to use channel 128, it is important to consider the implications of DFS rules, such as:
* The access point must support DFS and comply with the local regulations and standards that apply to DFS channels.
* The access point may experience delays or interruptions in its operation due to CAC or channel switching.
* The access point may have limited channel selection or availability due to radar interference or other Wi-Fi devices using DFS channels.
* The access point may have compatibility or interoperability issues with some client devices that do not support DFS or use different DFS parameters.
* The access point may have performance or quality issues due to co-channel or adjacent-channel interference from other Wi-Fi devices using non-DFS channels.
Therefore, it is advisable to use channel 128 only when necessary and after performing a thorough site survey and spectrum analysis to determine the best channel for the access point. References: 1, Chapter 3, page
117; 2, Section 3.2

The solution that you recommend is an Overlay WLAN monitoring solution. An Overlay WLAN monitoring solution is a system that uses dedicated sensors or probes to monitor the WLAN performance over time. The sensors are deployed throughout the WLAN coverage area and collect data on various metrics such as signal strength, noise level, channel utilization, interference, throughput, latency, packet loss, and QoS. The sensors send the data to a centralized server or appliance that analyzes the data and provides a single pane of glass for administration and monitoring of the solution. An Overlay WLAN monitoring solution can help to detect and troubleshoot WLAN issues, optimize WLAN performance, and generate reports and alerts. References: [CWNP Certified Wireless Network Administrator Official Study Guide:
ExamCWNA-109], page 538; [CWNA: Certified Wireless Network Administrator Official Study Guide:
ExamCWNA-109], page 508.

What is always required to establish a high quality 2.4 GHz RF link at a distance of 3 miles (5 kilometers) is a Fresnel Zone that is at least 60% clear of obstructions. The Fresnel Zone is an elliptical-shaped area around the line-of-sight path between two antennas that reflects and refracts the RF waves. The Fresnel Zone radius depends on the frequency of the RF signal and the distance between the antennas. For optimal performance, the Fresnel Zone should be at least 60% clear of any obstructions that may cause interference, attenuation, or multipath fading. The minimum output power level, antenna gain, and antenna type may vary depending on the environmental conditions and regulatory constraints, but they are not always required for a high quality RF link. References: [CWNP Certified Wireless Network Administrator Official Study Guide: ExamCWNA-109], page 75; [CWNA: Certified Wireless Network Administrator Official Study Guide: ExamCWNA-109], page
65.

FT (Fast Transition) is an IEEE 802.11 standard method for fast roaming. FT is defined in the IEEE 802.11r amendment and is also known as Fast BSS Transition (FBT) or Fast Secure Roaming. FT is a feature that allows a client station to quickly switch from one AP to another within the same ESS (Extended Service Set) without having to re-authenticate and re-associate with each AP. This reduces the latency and packet loss that may occur during roaming, thus improving the user experience and maintaining the security of the connection.
FT works by using pre-authentication and key caching mechanisms that allow the client station and the APs to exchange security information before the actual roaming occurs. This way, when the client station decides to roam to a new AP, it can use a fast reassociation request and response that contain only a few fields, instead of a full authentication and association exchange that require more time and data. References: 1, Chapter 9, page
367; 2, Section 6.3