Module 12 Pre-Assessment

Which type of management frame may regularly be broadcast by an AP?

• beacon

• probe request

• authentication

• probe response

Answer explanation

Beacons are the only management frame that may regularly be broadcast by an AP. Probing, authentication, and association frames are used only during the association (or reassociation) process.

What type of wireless antenna is best suited for providing coverage in large open spaces, such as hallways or large conference rooms?

• omnidirectional

• directional

• Yagi

• dish

Answer explanation

Omnidirectional antennas send the radio signals in a 360 degree pattern around the antenna. This provides coverage to devices situated anywhere around the access point. Dishes, directional, and Yagi antennas focus the radio signals in a single direction, making them less suitable for covering large, open areas.

What is an advantage of SSID cloaking?​

• It provides free Internet access in public locations where knowing the SSID is of no concern.

• Clients will have to manually identify the SSID to connect to the network.​

• SSIDs are very difficult to discover because APs do not broadcast them.​

• It is the best way to secure a wireless network.

Answer explanation

SSID cloaking is a weak security feature that is performed by APs and some wireless routers by allowing the SSID beacon frame to be disabled. Although clients have to manually identify the SSID to be connected to the network, the SSID can be easily discovered. The best way to secure a wireless network is to use authentication and encryption systems. SSID cloaking does not provide free Internet access in public locations, but an open system authentication could be used in that situation.

What are the two methods that are used by a wireless NIC to discover an AP? (Choose two.)

• sending an ARP request

• delivering a broadcast frame

• transmitting a probe request

• initiating a three-way handshake

• receiving a broadcast beacon frame

Answer explanation

Two methods can be used by a wireless device to discover and register with an access point: passive mode and active mode. In passive mode, the AP sends a broadcast beacon frame that contains the SSID and other wireless settings. In active mode, the wireless device must be manually configured for the SSID, and then the device broadcasts a probe request.

Which wireless network topology would be used by network engineers to provide a wireless network for an entire college building?

• ad hoc

• hotspot

• infrastructure

• mixed mode

Answer explanation

Ad hoc mode (also known as independent basic service set or IBSS) is used in a peer-to-peer wireless network such as when Bluetooth is used. A variation of the ad hoc topology exists when a smart phone or tablet with cellular data access is enabled to create a personal wireless hotspot. Mixed mode allows older wireless NICs to attach to an access point that can use a newer wireless standard.

What is a wireless security mode that requires a RADIUS server to authenticate wireless users?

• enterprise

• personal

• shared key

• WEP

Answer explanation

WPA and WPA2 come in two types: personal and enterprise. Personal is used in home and small office networks. Shared key allows three different authentication techniques: (1) WEP, (2) WPA, and (3) 802.11i/WPA2. WEP is an encryption method.

What two IEEE 802.11 wireless standards operate only in the 5 GHz range? (Choose two.)

• 802.11a

• 802.11b

• 802.11g

• 802.11ad

• 802.11ac

Answer explanation

The 802.11a and 802.11ac standards operate only in the 5 GHZ range. The 802.11b and 802.11g standards operate only in the 2.4 GHz range. The 802.11n standard operates in both the 2.4 and 5 GHz ranges. The 802.11ad standard operates in the 2.4, 5, and 60 GHz ranges.

A technician is configuring the channel on a wireless router to either 1, 6, or 11. What is the purpose of adjusting the channel?

• to disable broadcasting of the SSID

• to enable different 802.11 standards

• to provide stronger security modes

• to avoid interference from nearby wireless devices

Answer explanation

Channels 1, 6, and 11 are selected because they are 5 channels apart. thus minimizing the interference with adjacent channels. A channel frequency can interfere with channels on either side of the main frequency. All wireless devices need to be used on nonadjacent channels.

While attending a conference, participants are using laptops for network connectivity. When a guest speaker attempts to connect to the network, the laptop fails to display any available wireless networks. The access point must be operating in which mode?

• active

• mixed

• open

• passive

Answer explanation

Active is a mode used to configure an access point so that clients must know the SSID to connect to the access point. APs and wireless routers can operate in a mixed mode meaning that that multiple wireless standards are supported. Open is an authentication mode for an access point that has no impact on the listing of available wireless networks for a client. When an access point is configured in passive mode, the SSID is broadcast so that the name of wireless network will appear in the listing of available networks for clients.

A network administrator is required to upgrade wireless access to end users in a building. To provide data rates up to 1.3 Gb/s and still be backward compatible with older devices, which wireless standard should be implemented?

• 802.11n

• 802.11ac

• 802.11g

• 802.11b

Answer explanation

802.11ac provides data rates up to 1.3 Gb/s and is still backward compatible with 802.11a/b/g/n devices. 802.11g and 802.11n are older standards that cannot reach speeds over 1Gb/s. 802.11ad is a newer standard that can offer theoretical speeds of up to 7 Gb/s.