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In Juniper Networks Mist AI Wireless, the behavior described in this scenario is explained by dynamic rate shifting. Dynamic rate shifting is the mechanism by which a wireless client and access point automatically adjust the modulation and coding scheme (MCS) based on current RF conditions to maintain a reliable connection.

When a client is close to an access point, RF conditions are optimal—high RSSI, high signal-to-noise ratio (SNR), and low error rates—allowing the client to use higher-order modulation schemes such as 1024-QAM (in 802.11ax). These modulation schemes deliver higher throughput but require very clean RF conditions. As the client moves farther away from the AP, signal strength decreases and noise becomes more impactful, increasing frame errors and retransmissions.

Dynamic rate shifting continuously evaluates transmission success, retry rates, and acknowledgments. When errors increase, the client steps down to lower modulation rates (for example, from 1024-QAM to 256-QAM or 64-QAM) that are more resilient to reduced signal quality. This trade-off sacrifices peak throughput in favor of connection stability and reliability.

The other options describe contributing factors, but not the mechanism itself:

RSSI indicates signal strength but does not control rate selection.

SNR influences modulation decisions but is not the adaptive process.

Free space path loss explains why signal weakens over distance but does not describe how rates are adjusted.

Mist AI Wireless monitors modulation rates, retries, and throughput via advanced telemetry and uses this data in Wireless Assurance SLEs to highlight RF and performance issues. However, the actual process of stepping up or down transmission rates in response to changing RF conditions is governed by dynamic rate shifting.

Therefore, the correct answer is C. Dynamic rate shifting.

In Juniper Networks Mist AI Wireless, WxLAN policies are evaluated using a top-down, first-match logic. This means that when traffic matches a policy condition, that policy is applied immediately, and no further policies are evaluated. Understanding this evaluation order is critical when troubleshooting access discrepancies between user types such as BYOD and guest users.

From the scenario and the exhibit, guest devices are able to access youtube.com, while BYOD devices are blocked. This indicates that:

The guest WxLAN policy allows “All Video and Music” traffic (which includes YouTube).

The BYOD WxLAN policy blocks “All Video and Music” traffic.

The BYOD policy is evaluated before the guest policy.

Because BYOD users are matched to the BYOD label, their traffic hits the BYOD policy first and is denied before it can reach the more permissive guest policy. Simply modifying labels or deleting policies is unnecessary and could introduce unintended access control issues.

The correct and least disruptive solution is to move the BYOD WxLAN policy above the guest policy and then adjust the BYOD policy rules (for example, allowing YouTube or the “All Video and Music” category). By reordering the policies, you ensure that BYOD traffic is evaluated correctly and receives the intended permissions without impacting guest access.

The incorrect options are explained as follows:

Deleting policies (Options A and C) is not best practice and risks breaking segmentation and access control.

Option B is irrelevant, as the contractor policy does not affect BYOD or guest traffic in this scenario.

Therefore, the correct solution is to move the WxLAN policy for BYOD above the policy for guests, making Option D the correct answer.

In a traditional deployment, a Juniper Mist Access Point is a "cloud-first" device, meaning it expects a constant connection to the Mist Cloud to receive configuration updates and report telemetry. When performing an "AP-on-a-Stick" (APoS) site survey, the AP is often powered by a battery pack and moved to various locations where an active Ethernet backhaul or Internet connection is unavailable.3 To ensure the AP continues to broadcast the required SSIDs for signal measurement in this "disconnected" state, two specific settings must be adjusted within the Mist dashboard.

First, AP Config Persistence must be enabled. By default, Mist APs store their configuration in volatile memory; if an AP reboots (which happens when switching battery packs or moving locations) and cannot reach the Mist Cloud, it may fail to reload its previous configuration. Enabling Config Persistence ensures that the AP writes its current configuration to non-volatile flash memory, allowing it to boot up and start broadcasting the programmed SSIDs even in the absence of a cloud connection.4

Second, AP Uplink Monitoring must be disabled. Mist APs are designed with a safety mechanism where, if the AP loses its gateway connectivity (eth0 link or ping to the gateway), it will stop broadcasting SSIDs to prevent "black-holing" client traffic. In a site survey scenario, the Ethernet port is typically connected only to a battery or a passive PoE injector with no data path.5 If Uplink Monitoring remains active, the AP will detect the lack of a backhaul and disable its radios, making the survey impossible. By disabling this feature, the AP is forced to keep its radios active regardless of the uplink status. Together, these two settings allow the AP to function as a standalone signal source, which is essential for accurate RF environment mapping and pre-deployment validation using Mist AI hardware.