13.5.4 Module Quiz - WLAN Configuration (Answers)

13.5.4 Module Quiz – WLAN Configuration Answers

1. A user is configuring a wireless access point and wants to prevent any neighbors from discovering the network. What action does the user need to take?

Configure DMZ settings.
Configure a DNS server.
Disable SSID broadcast.
Enable WPA encryption.

Explanation: Disabling SSID broadcast prevents the access point from announcing the name of the network. Enabling WPA encryption, configuring DMZ settings, and configuring a DNS server will accomplish different tasks, but the name of the network will still be announced.

2. When a wireless network in a small office is being set up, which type of IP addressing is typically used on the networked devices?

network
public
wireless
private

Explanation: In setting up the wireless network in a small office, it is a best practice to use private IP addressing because of the flexibility and easy management it offers.

3. A user has just purchased a generic home router and would like to secure it. What should be done to help secure the wireless home router?

Change the default SSID.
Set a private IPv4 network for the internal network.
Allow only IPv6 traffic to enter the router.
Change the default administrator password.

Explanation: The home router allows a designated administrator to manage the network. Anyone who knows the account username and password can log into the router itself, which grants complete access to the features of the device and information about any devices that are connected. Most router manufacturers configure their new routers with the same default username and password and thus changing the default administrator password is a step towards securing the home router.

4. Which protocol could be used by a company to monitor devices such as a wireless LAN controller (WLC)?

SSH
NTP
PAT
SNMP

Explanation: The Simple Network Management Protocol (SNMP) is an application layer protocol used to monitor and manage the network. Network devices must be configured with a community name and IP address of the SNMP server.

5. When configuring a Cisco 3500 series wireless LAN controller (WLC) for a WPA2 Enterprise WLAN, what has to be created on the WLC before creating the new WLAN?

a security module
a new SSID
a VLAN for the wireless network
a security policy

Explanation: On a Cisco 3500 series wireless controller, a new interface for each new wireless network controlled by the WLC must be created. The interface and VLAN are created before configuring the wireless network.

6. What is a DHCP scope as it relates to a WLAN configured on the WLC controller?

a pool of IP addresses for WLAN clients
a corporate plan for allocation of IP addresses for wireless clients
security rules associated with DHCP for WLANs
the distance allotted for wireless clients that can receive IP addressing information

Explanation: When configuring a WLC controller as a DHCP server, use the DHCP Scope menu option to configure IP address-related settings such as the range of IP addresses to assign to WLAN devices, a DNS server address, and lease time.

7. Why would a technician configure a passphrase for a WLAN on a wireless router?

to protect someone from changing the configuration
to protect the SSID from being changed
to protect someone from cabling directly to the router and accessing the router
to configure wireless client authentication

Explanation: When a WLAN on a wireless router is being configured, a passphrase is used in the wireless security settings for a specific security mode. Clients must be configured for the same security mode and the same passphrase in order to access the WLAN.

8. A customer installs a wireless access point at home in the closet next to the kitchen. The customer mentions that the wireless communication performance seems degraded when the cordless phone or the microwave oven is in use. What is the possible reason for this degradation?

The surge of electricity when a microwave oven is in use disrupts the operation of the access point.
The cordless phone joins the WLAN and shares the available bandwidth.
The wireless signal is in the same radio frequency range as the household devices are in.
The access point is on the same electrical circuit as the phone base unit and microwave oven are.
The access point is close to walls.

Explanation: Because wireless networks use air as a medium, interference from other sources commonly cause degradation issues. Sources can include cordless phones, fluorescent lighting, microwave ovens, and other wireless devices that use the same frequencies.

9. What functionality is required on routers to provide remote workers with VoIP and videoconferencing capabilities?

IPsec
PPPoE
QoS
VPN

Explanation: Quality of service (QoS) needs to be enabled on routers to provide support for VoIP and videoconferencing. QoS refers to the capability of a network to provide better service to selected network traffic, as required by voice and video applications.

10. A wireless router is displaying the IP address of 192.168.0.1. What could this mean?

Dynamic IP address allocation has been configured on the router and is functioning correctly.
The wireless router has been configured to use the frequencies on channel 1.
The NAT function is not working on the wireless router.
The wireless router still has the factory default IP address.

Explanation: Wireless routers usually come with factory default settings. The IP address is often set to 192.168.0.1. The default username and password are often admin. The IP address, username, and password should all be modified to help secure the router.

11. A laptop cannot connect to a wireless access point. Which two troubleshooting steps should be taken first? (Choose two.)

Ensure that the wireless SSID is chosen.
Ensure that the correct network media is selected.
Ensure that the NIC is configured for the proper frequency.
Ensure that the laptop antenna is attached.
Ensure that the wireless NIC is enabled.

Explanation: A wireless laptop normally does not have an antenna attached unless a repair has recently been implemented. If the wireless NIC is enabled, the correct media, radio, will be used. When the NIC detects an access point, the correct frequency is automatically used.

12. In setting up a small office network, the network administrator decides to assign private IP addresses dynamically to workstations and mobile devices. Which feature must be enabled on the company router in order for office devices to access the internet?

UPnP
NAT
QoS
MAC filtering

Explanation: Network Address Translation (NAT) is the process used to convert private addresses to internet-routable addresses that allow office devices to access the internet.

13. What is a difference between autonomous APs that operate in a home environment and controller-based APs that operate in a corporate environment?

Controller-based APs can be automatically configured and managed by a WLAN controller.
Controller-based APs are known as lightweight APs and require an initial configuration to operate.
Autonomous APs do not support PoE.
Autonomous APs incorporate the functions of a router, switch, and AP into one device.

Explanation: Autonomous APs are standalone devices that are configured via Cisco CLI or a GUI. Controller-based APs are server-dependent devices that require no initial configuration to operate, because they are automatically configured and managed by a WLAN controller. Most autonomous and controller-based APs support PoE.

14. Which WLC tab would a network administrator typically use to see a summary view of the most heavily used WLANs including the number of clients using a particular WLAN?

Commands
Monitor
WLANs
Controller

Explanation: Use the Monitor tab and then the Summary option to see information about the WLC, including the IP address and system uptime as well as information associated with the top WLANs configured and active within the organization.

15. Users on an IEEE 802.11n network are complaining of slow speeds. The network administrator checks the AP and verifies it is operating properly. What can be done to improve the wireless performance in the network?

Switch to an 802.11g AP.
Split the wireless traffic between the 802.11n 2.4 GHz band and the 5 GHz band.
Set the AP to mixed mode.
Change the authentication method on the AP.

Explanation: The easiest way to improve wireless performance is to split the 802.11n wireless traffic between the 2.4 GHz band and the 5 GHz band. IEEE 802.11n networks can use the two bands as two separate wireless networks to help manage the traffic.

16. What is the first security setting that should be applied when connecting a wireless router in a small network?

Change the default administrative username and password.
Enable encryption on the wireless router.
Disable the wireless network SSID broadcast beacon.
Enable MAC address filtering on the wireless router.

Explanation: The first action that should be taken is to secure administrative access to the wireless router. The next action would usually be to configure encryption. Then after the initial group of wireless hosts have connected to the network, MAC address filtering would be enabled and SSID broadcast disabled. This will prevent new unauthorized hosts from finding and connecting to the wireless network.

17. Which option is an easy way to improve wireless performance on an 802.11n wireless router?

Connect a Wi-Fi range extender on the 2.4 GHz band to a wireless router on the 5 GHz band.
Require all wireless devices to use the 802.11g standard.
Use different SSID names for the 2.4 GHz and 5 GHz bands.
Use the same SSID name for all wireless bands.

Explanation: By default, dual-band routers and APs use the same network name on both the 2.4 GHz band and the 5 GHz band. The simplest way to segment traffic is to rename one of the wireless networks.

18. Which Cisco 3504 WLC dashboard menu option provides an overview of the number of configured wireless networks, associated access points (APs), and active clients?

Access Points
Advanced
Network Summary
Rogues

Explanation: The Cisco 3504 WLC dashboard displays when a user logs in to the WLC. It provides some basic settings and menus that users can quickly access to implement a variety of common configurations. The Network Summary page is a dashboard that provides a quick overview of the number of configured wireless networks, associated access points (APs), and active clients. You can also see the number of rogue access points and clients. The Advanced button displays the advanced Summary page providing access to all the features of the WLC.

19. Which protocol is used to monitor a network?

LWAPP
RADIUS
SNMP
WLC

Explanation: Simple Network Management Protocol (SNMP) is used to monitor the network.

20. Which service on a wireless router enables a host with an internal private IPv4 address to access an outside network using a public IPv4 address?

DHCP
DNS
LWAPP
NAT

Explanation: Any private IPv4 address cannot be routed on the Internet. The wireless router will use a service called Network Address Translation (NAT) to convert private IPv4 addresses to Internet-routable IPv4 addresses for wireless devices to gain access to the Internet.

21. Which service available on some wireless routers can be used to prioritize email over web data traffic?

DHCP
DNS
NAT
QoS

Explanation: Many wireless routers have an option for configuring quality of service (QoS). By configuring QoS, certain time-sensitive traffic types, such as voice and video, are prioritized over traffic that is not as time-sensitive, such as email and web browsing.

22. What must be done before creating a new WLAN on a Cisco 3500 series WLC?

Build or have a RADIUS server available.
Build or have an SNMP server available.
Create a new SSID.
Create a new VLAN interface.

Explanation: Each new WLAN configured on a Cisco 3500 series WLC needs its own VLAN interface. Therefore, it is required that a new VLAN interface be created first before a new WLAN can be created.

23. Which frequency band SSID name should users with time-sensitive applications connect to?

The 2.4 GHz band, because it is less crowded than the 5 GHz band.
The 2.4 GHz band, because it has more channels than the 5 GHz band.
The 2.4 GHz band, because the channel is likely interference-free.
The 5 GHz band, because it has more channels than the 2.4 GHz band.

Explanation: The 2.4 GHz band may be suitable for basic Internet traffic that is not time-sensitive. The 5 GHz band is much less crowded than the 2.4 GHz band; ideal for streaming multimedia. The 5 GHz band has more channels; therefore, the channel chosen is likely interference-free.

24. A Cisco 3500 series WLC is configured to access a RADIUS server. The configuration requires a shared secret password. What is the purpose for the shared secret password?

It allows users to authenticate and access the WLAN.
It is used by the RADIUS server to authenticate WLAN users.
It is used to authenticate and encrypt user data on the WLAN.
It is used to encrypt messages between the WLC and the server.

Explanation: The RADIUS protocol uses security features to protect communications between the RADIUS server and clients. A shared secret is the password used between the WLC and the RADIUS server. It is not for end users.

25. Which type of WLAN extends wireless coverage using a few APs controlled using a smartphone app?

Lightweight access point (LWAP)
Wi-Fi Extender
Wireless LAN Controller (WLC)
Wireless Mesh Network (WMN)

Explanation: Extending a WLAN in a small office or home has become increasingly easier. Manufacturers have made creating a wireless mesh network (WMN) simple through smartphone apps. You buy the system, disperse the access points, plug them in, download the app, and configure your WMN in a few steps.