Deck 6: Wi-Fi and Cellular Network

Question 1

Imagine a business network composed of an Ethernet switch, a router, and several access points as in the figure. In that setting, the LEAST popular configuration of the access point should be the ________ mode(s):

A) ad hoc
B) infrastructure
C) repeater
D) bridge
E) all of the above are equally popular

Answer 1

A

Question 2

The relationship between a Wi-Fi access point and a host is in one of two states. They are:

A) Authentication and control
B) Association and control
C) Authentication and transmission
D) Association and transmission
E) Authentication and association

Answer 2

E

Question 3

The wireless router used by home networks GENERALLY bundle the following functions EXCEPT:

A) DHCP service
B) Ethernet switch
C) Network address translation
D) Wireless access point
E) DSL or Cable modem

Answer 3

E

Question 4

IEEE802.11 supports at least two different solutions to authenticate user stations: open authentication and _____ authentication.

A) pre-shared key
B) closed key
C) public key
D) private key
E) dynamic key

Question 5

Which describes the IEEE 802.11 standard?

A) At an enterprise network, the router translates Wi-Fi frames into Ethernet frames.
B) With IEEE802.11n, multiple client stations can exchange data with an AP concurrently.
C) The pre-shared key authentication uses SSID for authentication.
D) At a home network, the pre-shared key is derived from the password/passphrase.
E) The AP acts as a router in the infrastructure mode.

Question 6

The ISM bands represent:

A) bands that are only for scientific and medical usage.
B) bands that belong to the microwave range.
C) bands that are controlled by FCC.
D) bands that do not need licensing.
E) bands that are exclusively used by IEEE 802.11.

Question 7

The Wi-Fi standard takes advantage of ______ frames to conduct necessary functions.

A) data, management, and security
B) data, management, and control
C) management, security, and control
D) routing, management, and security,
E) routing, management, and control

Question 8

Below figure represents a Wi-Fi network in its __________ mode.

A) ad hoc
B) and infrastructure
C) bridge
D) authentication
E) switch

Question 9

The Wi-Fi network has two setup modes of:

A) ad hoc and infrastructure
B) ad hoc and peer-to-peer
C) bridge and ad hoc
D) bridge and infrastructure
E) ad hoc and non ad-hoc

Question 10

What is the fundamental difference between the ad hoc and infrastructure modes in setting up the Wi-Fi network?

A) Use of one or more routers
B) Requirement of host authentication
C) Use of one or more access points
D) Requirement of host association
E) Requirement of using data encryptions

Question 11

Which information is LEAST likely included in the Wi-Fi access point's association table?

A) Host names
B) Each host's default gateway address
C) Each host's MAC address
D) Each host's authentication status
E) Each host's association status

Question 12

What is the name of a particular Wi-Fi network?

A) Service set identifier
B) Basic service set
C) Extended service set
D) Basic service set identifier
E) Extended service set identifier

Question 13

Which is NOT a Wi-Fi-related term?

A) Service set identifier
B) Basic service set
C) Extended service set
D) Basic service set identifier
E) Global service set

Question 14

Sometimes, the ____ is all it takes for a host station to join a Wi-Fi network.

A) digital certificate
B) public key
C) digital signature
D) service set identifier
E) beacon

Question 15

The media access control layer of IEEE802.11 conducts the following functions EXCEPT

A) Maintains communication reliability using acknowledgements.
B) Controls access (transmission) to the shared radio channel.
C) Protects frames with encryption.
D) Authenticates client stations.
E) Chooses a transmission channel randomly.

Question 16

Select a CORRECT statement of the IEEE802.11n standard.

A) It uses CSMA/CD to control data transmissions by host stations.
B) It supports only single-input-single-output between an AP and a client.
C) It works only in the 2.4GHz band.
D) It mandates RTS/CTS for media access control.
E) It supports quality of service (QoS) to deliver time sensitive frames without delays.

Question 17

Which may NOT represent a "general" function of the wireless access point?

A) Conversion (bridging) between Ethernet and Wi-Fi frames
B) IP address-based routing
C) Authentication of user stations/hosts
D) Media access control using RTS/CTS protocol
E) Data encryption to protect confidentiality

Question 18

The following characterizes the wireless LAN's MIMO technology EXCEPT?

A) It can support both single user and multi-user modes
B) The dual-band transmission that uses 2.4 and 5 GHz bands simultaneously is available.
C) Multiple data streams are created at once.
D) Neighboring channels can be bonded.
E) Frame acknowledgments are skipped.

Question 19

Which is INCORRECT regarding the Wi-Mesh network?

A) Wi-Mesh competes with WiMax, a fixed broadband wireless access standard.
B) Wi-Mesh requires physical wiring of every mesh point for a faster frame routing.
C) An IEEE standard for Wi-Mesh networking has been announced.
D) It is a good choice when an area lacks wired infrastructure.
E) Wi-Mesh runs on the Wi-Fi standard, but can cover a territory larger than the Wi-Fi LAN.

Question 20

Which is the LEAST likely function of the home network's wireless access router (AP)?

A) Wireless access point
B) Router
C) Repeater
D) Network address translation
E) Ethernet switch

Question 21

Which reflects a correct order of bandwidth from small to large?

A) frequency spectrum, service channel, service band
B) service channel, service band, frequency spectrum
C) service band, frequency spectrum, service channel
D) service channel, frequency spectrum, service band
E) service band, service channel, frequency spectrum

Question 22

Choose a CORRECT statement on Wi-Fi standards.

A) The dominant Wi-Fi standards today are 802.16 standards.
B) The coverage of Wi-Fi standards is limited to about 10 meters.
C) Wi-Fi standards compete with Ethernet.
D) Wi-Fi standards share the same frequency range being used by FM radio stations.
E) The Wi-Mesh network relies on frame routing by mesh points.

Question 23

Choose a CORRECT statement about the wireless access point (AP).

A) The Basic Service Set in the infrastructure mode does not need a AP.
B) The AP can use five frequency channels concurrently for frame transmissions.
C) The AP can communicate with two laptops at the same time.
D) The AP is a layer 2 device.
E) The ad-hoc mode Wi-Fi network needs only one AP.

Question 24

An 802.11g wireless AP is associated with eleven laptops. How many transmission channels can be used "at one point" for frame exchanges between a laptop and the AP?

A) only 1 channel
B) 2 channels, one for each direction
C) 3 non-overlapping channels
D) all 11 channels
E) anywhere between 1 and 11

Question 25

Which is CORRECT regarding IEEE 802.11 standards?

A) All standards except 802.11n rely on the spread spectrum technology.
B) Frequency bands used by the standards are licensed by the government.
C) Open authentication means that a user selected password is used for the authentication of a host station.
D) The standards allow hands-off between basic service sets.
E) In order to transmit frames, a host should associate with an AP first and then authenticate itself to the AP.

Question 26

Which is INCORRECT in describing the nodes of a "corporate" network in the figure?

A) The APs are operating in the infrastructure mode.
B) The APs should perform the bridge function to translate between Wi-Fi and Ethernet frames.
C) The APs are internet layer devices that rely on IP addresses to route packets.
D) The APs may authenticate host stations attempting to join the Wi-Fi network.
E) The APs utilize data encryption for secure communications with host stations.

Question 27

Choose a CORRECT statement of RTS/CTS.

A) It is the primary media access control mechanism for Wi-Fi.
B) This protocol is activated when there are many nodes within a basic service set (BSS).
C) This protocol is activated when there are many BSS within an ESS (extended service set).
D) This protocol may be activated when a Wi-Fi LAN experiences frequent collisions.
E) RTS communication is initiated by the wireless access point.

Question 28

Which is INACCURATE regarding the wireless access point(AP)?

A) It is equipped with its own WNIC (wireless NIC).
B) One of its main responsibilities in the infrastructure mode is to provide connectivity between Ethernet and Wi-Fi LANs.
C) It performs the CTS part of the RTS/CTS protocol to prevent frame collisions.
D) It is able to connect different subnetworks.
E) All host stations attached to an AP belong to a single subnet.

Question 29

Which is a CORRECT statement regarding the 802.11n Wi-Fi standard?

A) It uses a single-path propagation approach.
B) The 802.11n AP can use both 2.4Ghz and 5Ghz bands simultaneously.
C) The 802.11n AP can combine channel 1 and channel 11 to form a bigger transmission channel.
D) With 802.11n, all frames are treated equally with the same priority in delivery.
E) Its bandwidth is about the same as the 802.11g standard.

Question 30

Which of the following differs from the others in its frame type?

A) authentication frame
B) association frame
C) beacon frame
D) RTS/CTS frame
E) re-association frame

Question 31

The table of this kind should be maintained by _______:
$$\begin{array} { | c | c | c | c | } \hline \text { Host name } & \text { IP address } & \text { MAC address } & \text { State } \\\hline \text { Shin09 } & 172.26 .10 .1 & 0203.23 \text { AB.D051 } & \text { Associated } \\\hline \text { Jmon } & 172.26 .10 .12 & 0203.23 \text { A3.D591 } & \text { Authenticated } \\\hline \text { Glan7 } & 172.26 .10 .14 & 0203.236 B . A 031 & \text { Associated } \\\hline\end{array}$$

A) routers
B) switches
C) wireless access points
D) client host computers (e.g., laptops and PCs)
E) server host computers

Question 32

Which Wi-Fi standard boasts the highest throughput?

A) 802.11b
B) 802.11ax
C) 802.11g
D) 802.11n
E) 802.11ac

Question 33

Which is INCORRECT about the 802.11ac Wi-Fi standard?

A) 802.11ac utilizes only the 5.0GHz band and do not support the 2.4GHz band.
B) 802.11ac supports one channel speed of 160MHz for faster throughputs.
C) 802.11ac-enabled APs can switch the channel size (e.g., 20, 40, 80MHz) dynamically on a frame-by-frame basis.
D) 802.11ac supports only single-user MIMO.
E) 802.11ac supports up to 4 different data streams.

Question 34

Which Wi-Fi standard offers MIMO capability for a single user (single user MIMO)?

A) 802.11b
B) 802.11a
C) 802.11g
D) 802.11n
E) All of the above

Question 35

What is the maximum channel capacity of 802.11n that can be achieved with the channel bonding technology?

A) 40MHz
B) 20MHz
C) 30MHz
D) 80MHz
E) 60MHz

Question 36

The technologies of concurrent dual-band transmissions and non-concurrent dual-band transmissions are available with _______ Wi-Fi standard.

A) 802.11b
B) 802.11a
C) 802.11g
D) 802.11n
E) 802.11ac

Question 37

The 802.11n Wi-Fi product may come with the concurrent dual-band transmissions. Which is correct about the technology?

A) Two 2.4GHz frequency channels can be used concurrently to transmit data.
B) Two 2.4GHz and 5.0GHz frequency channels can be used concurrently to transmit data.
C) Two 5.0GHz frequency channels can be used concurrently to transmit data.
D) Within a Basic Service Set, two clients are allowed to exchange data with the AP through the same frequency channel.
E) Within a Basic Service Set, two clients are allowed to concurrently exchange data with the AP through two different channels of a frequency band (either 2.4 or 5GHz band).

Question 38

The following figure is a hypothetical corporate network with several APs. It indicates that at least one laptop computer is associated with each AP. Answer below question based on the figure.

-How many Basic Service Sets do you see in the enterprise network?

A) 4
B) 5
C) 6
D) 7
E) 9

Question 39

The following figure is a hypothetical corporate network with several APs. It indicates that at least one laptop computer is associated with each AP. Answer below question based on the figure.

-How many Extended Service Sets do you see in the enterprise network?

A) 1
B) 2
C) 3
D) 4
E) 9

Question 40

Which of the following is considered a 4G cellular standard?

A) GSM (Global System for Mobile Communications)
B) UMTS (Universal Mobile Telecommunications Systems)
C) CDMA2000 (Code Division Multiple Access 2000)
D) LTE (Long-Term Evolution)
E) AMPS (Advanced Mobile Phone Service)

Question 41

The following describe different aspects of the cell of the cellular wireless system EXCEPT:

A) It is designed to provide both voice and data communications.
B) High radio frequency ranges such as UHF, SHF, and EHF are used for communications.
C) Each cell is allocated a certain number of frequency channels, which limits the number of users that can be served at once.
D) Although cells may be hexagonal, square, circular or other regular shapes, circular remains a popular design choice.
E) Adjacent cells use different frequency ranges to avoid interference and to allow frequency reuse

Question 42

Which of the following is CORRECTLY paired?

A) GSM -- digital, packet switching technology
B) UMTS -- digital, packet switching technology
C) CDMA2000 -- digital, circuit switching technology
D) LTE -- digital, circuit switching technology
E) AMPS -- digital, circuit switching technology

Question 43

Which of the following is considered as the most advanced multiple access technology considering its adoption by the latest generation of cellular service?

A) FDMA (Frequency Division Multiple Access)
B) TDMA (Time Division Multiple Access)
C) CDMA (Code Division Multiple Access)
D) OFDMA (Orthogonal Frequency Division Multiple Access)
E) CDMA2000 (Code Division Multiple Access2000)