Wireless LAN and WLC Scenarios

Increase AP transmit power to maximize coverage.

Why wrong: Higher power increases cell overlap and co-channel interference.

Enable 2.4 GHz band only to maximize range.

Why wrong: 2.4 GHz has limited channels and is more prone to interference.

WPA3-PSK with AES

Why wrong: WPA3 uses SAE, not PSK.

WPA2-PSK with TKIP

Why wrong: TKIP does not use AES.

WEP with AES

Why wrong: WEP does not support AES.

The APs are not configured with DHCP option 43 to point to the WLC.

Why wrong: Incorrect because DHCP option 43 is used for APs in different subnets; since APs are in the same VLAN, they can use Layer 2 CAPWAP discovery and do not need option 43.

The APs are running an incompatible IOS version that does not support CAPWAP.

Why wrong: Incorrect because CAPWAP is supported on most modern APs; version incompatibility would typically cause a different error, not a failure to join.

The APs must be assigned a static IP address to join the WLC.

Why wrong: Incorrect because APs can use DHCP to obtain an IP address; static IP is not a requirement for CAPWAP discovery.

The guest SSID is configured with open authentication, which does not support captive portal.

Why wrong: Incorrect because open authentication is commonly used with captive portals; the portal handles authentication after association.

The WLC does not have a dedicated guest interface configured.

Why wrong: Incorrect because a dedicated guest interface is not mandatory; the WLC can use a VLAN interface for guest traffic.

The captive portal requires a RADIUS server to be configured on the WLC.

Why wrong: Incorrect because captive portal can use local authentication or an external web server; RADIUS is optional.

Centralized WLC architecture, because it provides better RF management and security.

Why wrong: Incorrect because centralized architecture adds latency due to CAPWAP tunneling, which is detrimental to real-time applications.

Centralized WLC architecture, because it requires fewer access points to cover the warehouse.

Why wrong: Incorrect because the number of APs depends on coverage requirements, not the architecture type.

Converged access (SD-Access) wireless, because it requires fewer WLCs to manage the network.

Why wrong: Incorrect because SD-Access may still require multiple WLCs for redundancy and scale; the primary advantage is local switching, not WLC count reduction.

The 802.11a/n standard is obsolete and does not support mesh networking.

Why wrong: Incorrect because 802.11a/n is widely used for mesh backhaul and is not obsolete.

The mesh APs require a wired Ethernet connection to the root AP.

Why wrong: Incorrect because mesh APs communicate wirelessly; only the root AP needs a wired connection.

The 2.4 GHz band provides better range for backhaul than the 5 GHz band.

Why wrong: Incorrect because 5 GHz typically offers higher throughput and is preferred for backhaul, though range is shorter; the issue is interference, not range.

The AP is overloaded with too many clients.

Why wrong: Incorrect because client overload would affect wireless performance, not cause CRC errors on the wired uplink.

The switch port is configured with a duplex mismatch.

Why wrong: Incorrect because duplex mismatch typically causes runts, giants, and alignment errors, not just CRC errors.

The AP is not receiving enough power from Power over Ethernet (PoE).

Why wrong: Incorrect because insufficient PoE would cause the AP to reboot or not power on, not generate CRC errors.

Clients must be configured to roam between WLCs, which is not supported in active/standby mode.

Why wrong: Incorrect because clients do not need to roam; APs handle the failover by rejoining the standby WLC.

The SSID name must be different on the standby WLC to avoid conflicts.

Why wrong: Incorrect because the SSID should be the same to provide seamless service after failover.

The APs must be rebooted after the active WLC fails to recognize the standby WLC.

Why wrong: Incorrect because APs automatically detect the failure and attempt to join the standby WLC if configured.

Adjacent channel interference from access points using channels 10 and 12.

Why wrong: Incorrect because adjacent channel interference would occur if channels overlapped, but the scenario states other APs are using channel 11, not adjacent channels.

Non-WiFi interference from devices like microwaves or cordless phones.

Why wrong: Incorrect because the spectrum analyzer showed high utilization on channel 11, but non-WiFi interference would likely affect multiple channels or be intermittent.

The access point is overloaded with too many clients.

Why wrong: Incorrect because client overload would cause high utilization but not necessarily the specific pattern of disconnections; co-channel interference is more likely given neighboring APs.

AP-1 is a lightweight AP and AP-2 and AP-3 are autonomous APs.

Why wrong: All APs are lightweight (CAP and AIR-AP models) and managed by the WLC.

AP-3 has a hardware failure because its model is different.

Why wrong: Different models are normal; no failure is indicated.

The WLC is running a software version that only supports AP-2 and AP-3.

Why wrong: All APs are supported as they are all running the same software version.

All clients are fully associated and passing traffic.

Why wrong: The client with MAC 00:11:22:33:44:88 is in Probe state, not Run.

The client with MAC 00:11:22:33:44:55 has the best signal strength.

Why wrong: The client with MAC 77 has RSSI -60, which is better than -65.

All clients are using 802.11ac or higher.

Why wrong: One client uses 802.11n, which is not ac or higher.

The AP is operating in Local mode and will tunnel all traffic to the WLC.

Why wrong: The mode is FlexConnect, not Local.

The AP will only work if the WLC is directly connected at Layer 2.

Why wrong: FlexConnect is designed for remote sites over WAN.

The AP is in Monitor mode and will not serve clients.

Why wrong: FlexConnect mode serves clients.

Configure 802.1X authentication for the guest SSID as well.

Why wrong: Incorrect because guest SSID typically uses open authentication with a captive portal; 802.1X would require credentials and is not suitable for guests.

Apply a VLAN ACL on the guest VLAN to block access to internal subnets.

Why wrong: Incorrect while a VLAN ACL could help, it does not prevent guest-to-guest communication; client isolation is more direct and effective.

Place the guest SSID on the same VLAN as the employee SSID.

Why wrong: Incorrect because placing guest and employee traffic on the same VLAN would defeat security; they should be on separate VLANs.

The AP is operating in FlexConnect mode.

Why wrong: The output clearly shows AP Submode: Normal and AP Mode: Local, not FlexConnect.

The AP is in Monitor mode and will not serve clients.

Why wrong: The mode is Local, which serves clients.

The AP has a join priority of 1, meaning it is the highest priority.

Why wrong: Join priority is a value used for AP selection, but the output does not indicate it is the highest; typically lower numbers are higher priority, but 1 is indeed high.

The APs require a separate management IP address to broadcast SSIDs.

Why wrong: Incorrect because APs use the IP address assigned by the WLC; they do not need a separate management IP for SSID broadcast.

The WLC is running an IOS version that does not support the AP model.

Why wrong: Incorrect because if the APs joined the WLC, the IOS version is compatible; otherwise, they would not join at all.

The APs must be rebooted after joining the WLC to start broadcasting SSIDs.

Why wrong: Incorrect because APs do not require a reboot after joining; they begin broadcasting once configured.