CCNA Module 4

Which of the following WLC interfaces or ports should be used to make a connection between a VLAN and a WLAN?

• Distribution system ports

• Management interface

• Service port

• Virtual interface

• Dynamic interface

Answer explanation

WLC dynamic interfaces are used to make a logical connection between a wired VLAN and a WLAN. On an IOS-XE WLC, the dynamic interface is simply the respective VLAN itself.  Distribution system ports connect the WLC to the physical network where VLANs exist, while the WLC touches wireless users through its APs and WLANs. The management interface is used for only WLC management traffic. The service port is used for out-of-band management, and the virtual interface is used to relay client mobility functions like DHCP and web authentication.

Using WLC Interfaces Page number:1195

What is the default session timeout that a controller enforces on wireless clients that connect to a WLAN?

• 60 seconds

• 600 seconds

• 1800 seconds

• 86400 seconds

• 0 seconds

Answer explanation

By default, clients are limited to a session timeout of 1800 seconds (30 minutes). You can configure the session timeout to be a value from 0 (no timeout) to 86400 seconds; if 802.1x is in use, the minimum timout is 300 seconds.

Configuring a WLAN on an IOS-XE WLC Page number:1206

Suppose you are configuring a new WLAN for your network and need to specify the SSID string for it. How many characters can you enter in the SSID string?

• 10

• 32

• 64

• 256

Answer explanation

The SSID string can contain 1 to 32 ASCII characters. Spaces and other printable special characters are allowed.

Configuring a WLAN on an IOS-XE WLC Page number:1206

By default, a wireless LAN controller will not allow ____________ traffic initiated from a WLAN?

• IP

• VLAN

• management

• encrypted

Answer explanation

As a default security measure, a wireless LAN controller will not allow management traffic to itself when initiated from a WLAN.

Configuring a WLAN Page number:1204

Suppose a Cisco WLC has one service port, one redundancy port, four distribution system ports, and one console port. To gain the most advantage out of the four distribution system ports with load balancing and redundancy, which of the following would be the best strategy?

• Configure the distribution ports individually as access links.

• Configure the distribution ports as a trunk link LAG.

• Configure the distribution ports individually as trunk links.

• Configure the distribution ports as an access link LAG.

Answer explanation

Because the WLC has four distribution system ports, they should be configured as a single logical LAG (link aggregation group). Distribution system ports should also always be configured as trunk links so that multiple VLANs can be mapped to WLANs on the WLC.

Using WLC Ports Page number:1198

Suppose you need to connect two new Cisco APs to a switched network. One is an autonomous AP, the other a lightweight AP. The APs will be used to provide four WLANs that map to four VLANs. Which of the following correctly describes the wired network link that connects to the autonomous and lightweight APs, respectively?

• access mode, access mode

• access mode, trunk mode

• trunk mode, access mode

• trunk mode, trunk mode

Answer explanation

The autonomous AP will need a wired link configured in trunking mode so that all four VLANs can be carried over the single link. The lightweight AP needs its wired connection configured in access mode. The same four VLANs will be available at the AP, but they will be carried between the WLC and AP over CAPWAP tunnels.

Connecting a Cisco AP Page number:1197

When configuring a wireless LAN from an AireOS WLC, you create a dynamic interface and a wireless LAN. Which answers identify the correct configuration area where you configure the stated parameters? (Choose three answers.)

• VLAN ID on the dynamic interface creation page

• WLAN ID on the dynamic interface creation page

• WLAN ID on the WLAN creation page

• SSID on the dynamic interface creation page

• SSID on the WLAN creation page

Answer explanation

The dynamic interface and WLAN configurations in an AireOS WLC define the settings for a LAN's wired (dynamic interface) and wireless (WLAN) sides. The dynamic interface creation page gives input fields for:

•    A dynamic interface name
•    The numeric VLAN ID used on the wired network (the distribution system)

The wireless LAN creation page allows for the definition of:

•    The wireless LAN profile name
•    The SSID
•    A numeric WLAN ID (1-512)

To connect the parameters together, the WLAN configuration page has a field that references the dynamic interface name.

Of the various answers, one correct answer notes that you must configure the VLAN ID on the dynamic interface creation page. The other two correct answers list settings made on the WLAN creation page: the WLAN ID and the SSID.
 

Which one of the following is a type of traffic that does not terminate on an IOS-XE controller’s wireless management interface?

• CAPWAP tunnels

• GUI sessions

• SSH sessions

• Wireless client VLANs

Answer explanation

The WMI is used to terminate many different types of management traffic, such as CAPWAP tunnels, GUI and SSH sessions to the WLC, SNMP, NTP, syslog, and so on. The VLANs that map to wireless client traffic pass over Layer 2 dynamic controller interfaces and do not terminate on the WMI.

WLC Logical Interfaces Page number:1198

The AP in the figure supports three separate wireless virtual LANs. What type of link needs to be used between the AP and the LAN switch if the AP is part of a split-MAC architecture?

• Access port

• WLC port

• Routed port

• Trunk port

Answer explanation

Because the AP is part of a split-MAC architecture, so it must join with a WLC. Regardless of the number of VLANs to support on the wireless side, the AP requires only an access mode switch port. The multiple VLANs are carried over a CAPWAP tunnel between the AP and WLC, so no trunk port is needed. 

The switch would not use a routed port because the AP does not act as a layer 3 device. A WLC port is not a type of switch port at all, so it is incorrect too.

Connecting a Cisco AP Page number:1197

Which of the following things must be identified when configuring a new secure WLAN on a WLC? (Select 3)

• BSSID of the WLAN

• SSID of the WLAN

• Dynamic interface

• WPA version

• Channels to use

Answer explanation

A new WLAN must be configured with an SSID string, the appropriate dynamic interface, and the WPA version. Remember that the dynamic interface is used to logically map a VLAN to a WLAN. The WLAN configuration does not define the BSSID; that is determined by each AP and the WLAN it offers. In addition, you cannot specify specific channel numbers to use on the WLAN. Channels can be configured for a band or an RF profile as part of more advanced wireless functions on the WLC GUI.

Step 3. Create a New WLAN Page number:1219