IS302 Exam 2 Ch 6

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The frequency spectrum extends ________. A) into the megahertz range B) into the gigahertz range C) into the visible light range D) into the ultraviolet range E) to infinity

E) to infinity

MIMO ________. A) increases throughput B) lowers propagation distance C) Both A and B D) Neither A nor B

A) increases throughput

A wireless host sends a packet to a server on the company's wired Ethernet LAN via an access point. How many frames will be involved in this one-way transmission? A) 1. B) 2. C) 3. D) 4. E) There will be one frame for each switch along the way.

B) 2.

The 2.4 GHz band supports ________ nonoverlapping channels. A) 1 B) 3 C) 7 D) 11 E) more than 11

B) 3

802.11g has a rated speed of ________. A) 11 Mbps B) 54 Gbps C) 300 Mbps D) 1 Gbps

B) 54 Gbps

Which of the following brings gigabit speeds to clients? A) 802.11n B) 802.11ac C) 802.11g D) None of the above

B) 802.11ac

If an 802.11n access point and an 802.11g client communicate, they communicate using ________. A) 802.11n B) 802.11g C) Either A or B D) Neither A nor B

B) 802.11g

Signals usually ________. A) travel at a single frequency B) spread over a range of frequencies

B) spread over a range of frequencies

Which form of spread spectrum transmission divides the channel into many smaller channels called subcarriers? A) DSSS. B) FHSS. C) OFDM. D) All of the above. E) None of the above.

C) OFDM.

Wi-Fi operates in the 2.4GHz and 5GHz _____ A) Spectrums B) Frequencies C) Channels D) Service bands

D) Service bands

Which unlicensed band is defined the same way in most countries around the world? A) 2.4 GHz. B) 5 GHz. C) Both A and B D) None of the above.

A) 2.4 GHz.

Which unlicensed band provides greater propagation distance for a given level of power? A) 2.4 GHz. B) 5 GHz. C) Both A and B allow about the same propagation distance.

A) 2.4 GHz.

Which of the following can operate in the 5 GHz band? A) 802.11ac B) 802.11g C) Both A and B D) Neither A nor B

A) 802.11ac

When two devices communicate using NFC, how close must they be? A) A few inches B) Up to 50 feet C) Up to 5 feet D) Up to 10 feet

A) A few inches

What propagation problem becomes worse as frequency increases? A) Absorptive attenuation. B) Electromagnetic interference. C) Both A and B D) Neither A nor B

A) Absorptive attenuation.

To use an access point, you need to know its ________. A) BSSID B) SSID C) Wi-Fi ID D) ESSID

B) SSID

In ________, when a wireless host wishes to send, it first sends a message to the wireless access point asking for permission to send. When the access point sends back a response, the host sending the original message may transmit. All other hosts must wait. A) CSMA/CA+ACK B) CSMA/CA C) CSMA/CD D) RTS/CTS

D) RTS/CTS

At 10 meters, a signal has a strength of 100 mW. About how strong will it be at 40 meters? A) about 0.5 mW B) about 5 mW C) about 25 mW D) about 6 mW

D) about 6 mW

The most serious problem with wireless transmission in WLANs is ________. A) inverse square law attenuation B) absorptive attenuation C) shadow zones D) multipath interference

D) multipath interference

To transmit very rapidly in RADIO, you need ________. A) single-frequency transmission B) single-mode transmission C) multimode transmission D) wide bandwidth E) narrow bandwidth

D) wide bandwidth

If there is an access point that serves eight wireless hosts, on how many channels will these devices transmit and receive during the course of an hour or two? A) 1 B) 2 C) 8 D) 9

A) 1

There is an access point that serves eight wireless hosts. On how many channels will these devices transmit during the course of an hour or two? A) 1. B) 2 (one in each direction). C) 7. D) 8. E) 9.

A) 1.

Which of the following is more efficient and faster? A) CSMA/CA+ACK. B) RTS/CTS. C) Both are about equally efficient.

A) CSMA/CA+ACK.

802.11i 802.1X initial authentication mode was created for ______ A) Corporations with multiple access points B) Corporations with less than eight access points C) Residences with a single access point D) Residences with more than eight access points

A) Corporations with multiple access points

The downside of unlicensed bands is potential _____ A) Interference from others B) Less-developed standards C) Speed loss D) Loss of flexibility

A) Interference from others

Wireless network standards come from ________. A) OSI B) TCP/IP C) Both A and B D) Neither A nor B

A) OSI

A group of devices on a desk that communicate wirelessly is called a ____ A) PAN B) MAN C) WAN D) LAN

A) PAN

What aspect of 802.11 standards affects interference between nearby access points? A) The number of possible nonoverlapping channels. B) The standard's minimum spacing parameter. C) RTS/CTS. D) All of the above.

A) The number of possible nonoverlapping channels.

What happens if two nearby access points use the same channel? A) They will interfere with each other. B) They will be bonded for joint operation automatically. C) They will be bonded for joint operation automatically if they use CSMA/CA+ACK. D) They will be bonded for joint operation automatically if they use RTS/CTS.

A) They will interfere with each other.

As a wireless host moves farther from a wireless access point, it is likely to transition to a slower modulation method. A) True. B) False.

A) True.

CSMA/CA+ACK is reliable. A) True. B) False.

A) True.

In 802.11 WLANs, the terms handoff and roaming mean the same thing. A) True. B) False.

A) True.

Individual throughput falls as the number of wireless hosts using an access point increases. A) True. B) False.

A) True.

The signal strength at 20 meters is 90 mW the signal strength at 60 meters would be 10 mW. A) True. B) False.

A) True.

When a wireless NIC receives a frame correctly, it immediately sends back a reply without listening for traffic. A) True. B) False.

A) True.

Which of the following is not true in regard to upgrading to Wi-Fi 6? A) Upgrading Wi-Fi routers and access points is a must B) Supports faster speeds C) Compatible with previous versions of wi-fi D) There are not additional infrastructure upgrades required

A) Upgrading Wi-Fi routers and access points is a must

Wi-Fi is a term used by the ________. A) Wi-Fi Alliance B) IEEE C) both A and B D) neither A nor B

A) Wi-Fi Alliance

If a radio transmission is easily blocked by obstacles, then you need to maintain ________. A) a clear line of sight B) spread spectrum transmission integrity C) broadband transmission D) deep transmission E) shadow zone transmission

A) a clear line of sight

What propagation problem is especially bad in moist air? A) absorptive attenuation B) electromagnetic interference C) multipath interference D) inverse square law attenuation

A) absorptive attenuation

Cellular telephony uses ________. A) an omnidirectional antenna B) a dish antenna C) Both A and B D) Neither A nor B

A) an omnidirectional antenna

In CSMA/CA, CS means ________. A) carrier sense B) carriage suspension C) cancel sending D) counter-source

A) carrier sense

In the 60 GHz service band, ________. A) channel bandwidth can be very wide B) signals travel farther C) Both A and B D) Neither A nor B

A) channel bandwidth can be very wide

To handle multiple conversations in radio transmission, you use multiple ________. A) channels B) frequencies C) service bands D) UWBs E) wires

A) channels

Smart antennas can ________. A) direct signal strength at individual wireless hosts B) transmit multiple spatial data streams in the same channel C) Both A and B D) Neither A nor B

A) direct signal strength at individual wireless hosts

If more users move to an access point, this decreases ________. A) individual throughput B) aggregate throughput C) Both A and B D) Neither A nor B

A) individual throughput

Spread spectrum transmission is used in WLANs because ________. A) it is required by regulators B) it offers strong security C) Both A and B D) Neither A nor B

A) it is required by regulators

Interference is minimized in ________. A) licensed bands B) unlicensed bands

A) licensed bands

Companies are moving to the 5 GHz band because there is ________ than in the 2.5 GHz band. A) more bandwidth B) less absorptive attenuation C) both A and B D) neither A nor B

A) more bandwidth

In an extended service set, each access point ________. A) must have the same SSID B) must have different SSIDs C) must have coordinated SSIDs D) none of the above

A) must have the same SSID

Mesh networking in 802.11 is likely to use ________. A) only wireless devices B) wireless devices and the site's wired LAN C) Both A and B

A) only wireless devices

CSMA/CA+ACK usually is ________. A) required B) optional C) not important D) efficient

A) required/mandatory

Wireless access points typically link wireless clients to ________. A) servers on the wired network B) wireless servers C) both A and B

A) servers on the wired network

Wireless network standards operate at ________. A) the data link layer B) the internet layer C) Both A and B D) Neither A nor B

A) the data link layer. The data link layer and the physical layer.

In unlicensed bands, ________. A) you can use radios wherever you please B) you can prevent nearby businesses from setting up access points in the same channel C) Both A and B D) Neither A nor B

A) you can use radios wherever you please

To handle multiple conversations in 802.11 transmission, you normally use multiple A) Service bands B) Channels C) Frequencies D) Wires

B) Channels

Access points take frames from wireless devices and send these frames on to devices on the wired LAN. They also do the converse. A) True. B) False.

B) False.

An access point and a host it serves can transmit to each other simultaneously. A) True. B) False.

B) False.

Radio has more reliable transmission than UTP. A) True. B) False.

B) False.

Spread spectrum transmission is used in commercial WLANs for security reasons. A) True. B) False.

B) False.

The most rapidly growing 802.11 LAN standard today is 802.11g. A) True. B) False.

B) False.

The most widely used 802.11 LAN standard today is 802.11n. A) True. B) False.

B) False.

The terms channel and service band mean roughly the same thing. A) True. B) False.

B) False.

There is less interference in the 2.4 GHz band than in the 5 GHz band. A) True. B) False.

B) False. More interference

Which of the following is usually optional in access point operation? A) CSMA/CA+ACK. B) RTS/CTS. C) Both A and B D) Neither A nor B

B) RTS/CTS.

What is the main problem the 802.11ax standard of Wi-Fi 6 addresses? A) Ease of use B) Security C) Large number of devices D) Speed

B) Security

When a wireless NIC wishes to transmit, it listens for traffic. If there is traffic, it waits. If there is no traffic, it may transmit. A) True. B) Sometimes true. C) False.

B) Sometimes true.

Compared to wired transmission, propagation problems in radio transmissions are _____ A) Better B) Worse C) About as bad

B) Worse

The other wireless device is far away in a known direction. You should use ________. A) an omnidirectional antenna B) a dish antenna C) Both A and B D) Neither A nor B

B) a dish antenna

An 802.11g access point has an actual speed of 30 MHz. This is ________. A) the rated speed B) aggregate throughput C) channel bandwidth

B) aggregate throughput

To transmit data very rapidly, you would want a ________ channel. A) narrowband B) broadband C) single-frequency band D) Any of the above.

B) broadband

Wireless radio transmission usually is expressed in terms of ________. A) wavelength B) frequency C) Both A and B D) Neither A nor B

B) frequency

Frequency is measured in terms of ________. A) nanometers B) hertz C) Both A and B D) Neither A nor B

B) hertz

CSMA/CA+ACK is ________. A) efficient B) inefficient

B) inefficient

In the Shannon Equation, C is the ________. A) actual speed of transmission in a channel B) maximum possible speed of transmission in a channel C) minimum possible speed of transmission in a channel D) channel bandwidth E) signal-to-noise ratio

B) maximum possible speed of transmission in a channel

Spread spectrum transmission is used in WLANs for ________. A) higher transmission speed B) more reliable transmission C) greater security D) All of the above.

B) more reliable transmission

Wi-Fi normally uses a(n) ________. A) dish antenna B) omnidirectional antenna C) both A and B D) neither A nor

B) omnidirectional antenna

Access points take ________ from wireless devices and send them on to devices on the wired LAN. They also do the converse. A) frames B) packets

B) packets

Attenuation with distance is faster with ________. A) UTP transmission B) radio transmission C) Both A and B D) Neither A nor B

B) radio transmission

Traditional MIMO can ________ A) send signals to two different clients at the same time B) send multiple signals in the same channel C) Both A and B D) Neither A nor B

B) send multiple signals in the same channel

WLANs normally use ________. A) licensed bands B) unlicensed bands

B) unlicensed bands

In 802.11, channel bandwidth usually is ________. A) 20 GHz B) 40 GHz C) 20 MHz D) 40 MHz

C) 20 MHz

802.11n may offer a rated speed of about ________. A) 11 Mbps B) 54 Mbps C) 300 Mbps D) 3 Gbps

C) 300 Mbps

In the 5 GHz band, how many channels can you have with 802.11ac with 80 GHz channels? A) 1 B) 12 C) 6 D) 24

C) 6

Wireless LAN standards are created by the ________ Working Group. A) 802.1 B) 802.3 C) 802.11 D) 802.3W

C) 802.11

For wireless backup, which of the following is adequate? A) 802.11g B) 802.11n C) 802.11ac D) All of the above

C) 802.11ac

Which of the following can offer speeds of about a gigabit per second? A) 802.11g. B) 802.11n. C) 802.11ac. D) None of the above.

C) 802.11ac.

For which standard is 300 Mbps a typical rated speed? A) 802.11ad. B) 802.11ac. C) 802.11n. D) 802.11g.

C) 802.11n.

802.11 standards are being developed to work in the ________ unlicensed band. A) 2.4 GHz B) 5 GHz C) Both A and B D) None of the above.

C) Both A and B

802.11ad will ________. A) operate in the 60 GHz radio band B) have short propagation distance C) Both A and B D) Neither A nor B

C) Both A and B

802.11n is designed to operate in the ________ unlicensed band. A) 2.4 GHz B) 5 GHz C) Both A and B D) Neither A nor B

C) Both A and B

802.11n is faster than 802.11g because 802.11n ________ A) is designed to use wider channels B) can send multiple signals (spatial transmission speeds) in a single channel C) Both A and B D) Neither A nor B

C) Both A and B

802.11n will be superior to current 802.11 standards by ________. A) offering wider channels B) sending multiple spatial data streams in a single channel between wireless access points and wireless NICs C) Both A and B D) Neither A nor B

C) Both A and B

Beamforming can ________. A) direct signal strength at individual wireless hosts B) transmit multiple spatial data streams in the same channel C) Both A and B D) Neither A nor B

C) Both A and B

Beamforming can allow an access point to ________. A) send signals to two different clients at the same time B) direct power to individual clients C) Both A and B D) Neither A nor B

C) Both A and B

MIMO increases ________. A) throughput B) propagation distance C) Both A and B D) Neither A nor B

C) Both A and B

Media access control governs transmission by ________. A) access points B) wireless NICs C) Both A and B D) Neither A nor B

C) Both A and B

What propagation problem becomes worse as frequency increases? A) Absorptive attenuation. B) Shadow zones. C) Both A and B D) Neither A nor B

C) Both A and B

When a host moves from one wireless access point to another in a WLAN, this is ________. A) a handoff B) roaming C) Both A and B D) Neither A nor B

C) Both A and B

Which of the following is true? A) An 802.11n host can work with an 802.11g access point. B) An 802.11g host can work with an 802.11n access point. C) Both A and B D) Neither A nor B

C) Both A and B

Which of the following uses OFDM? A) 802.11g. B) 802.11n. C) Both A and B D) Neither A nor B

C) Both A and B

Most wireless systems operate in the ________ range. A) hz B) kHz C) GHz D) MHz

C) GHz

An access point can transmit to more than one wireless client at a time with A) MIMO B) CSMC/CA+ACK C) Multiuser MIMO D) Bonding

C) Multiuser MIMO

Bluetooth use ______operation. A) Point-to-multipoint B) One-to-all C) One-to-one D) All-to-all

C) One-to-one

How does WPA3 help keep devices on a public, open network secure? A) It requires a facial recognition scan at the access point B) It requires users to establish physical connections with the network C) WPA3 individually encrypts each device that connect to the network D) WPA3 will require a fee in Dogecoin to use the network

C) WPA3 individually encrypts each device that connect to the network

In the Shannon Equation, if you quadruple the bandwidth in a channel while the signal-to-noise ratio remains the same, you can transmit ________. A) Log2(1+4) times as fast B) Log2(1+1/4) times as fast C) about 4 times as fast D) about 1/4 as fast E) at the same speed, but more reliably

C) about 4 times as fast

In 802.11 networks, the speed I receive on my portable devices is a(n) ________. A) individual throughput B) rated speed C) aggregate throughput D) None of the above

C) aggregate throughput

In CSMA/CD+ACK, when a wireless NIC wishes to transmit, it listens for traffic. If there is traffic, it waits. When the traffic stops, it may transmit immediately. A) always true B) sometimes true C) always false

C) always false

An extended service set (ESS) is a group of BSSs that ________. A) are connected to the same distribution system B) have the same SSID C) both A and B D) neither A nor B

C) both A and B

The messages of VPNs ________. A) are encrypted B) share the public network like Internet C) both A and B D) neither A nor B

C) both A and B

A channel has more bandwidth than is necessary given data transmission speeds requirements in ________ transmission. A) normal radio B) reliable commercial C) spread spectrum transmission D) licensed E) None of the above.

C) spread spectrum transmission

MIMO ________. A) uses a single spatial stream but multiple signals B) bonds channels for higher speed C) transmits multiple signals in the same channel D) is used in all forms of 802.11

C) transmits multiple signals in the same channel

Using unused transmission channels in a service band is called using ________. A) dark spectrum B) opportunistic agility C) white space D) a smart antenna

C) white space

The most widely used 802.11 standard today is ________. A) 802.11a B) 802.11b C) 802.11e D) 802.11g E) 802.11n

D) 802.11g

________ is a technique for preventing two wireless stations from interfering with each other by transmitting at the same time. A) Creating extended service sets B) The distribution system C) Roaming D) Media access control

D) Media access control

802.11a supports ________ nonoverlapping channels. A) 1 B) 3 C) 7 D) More than 10

D) More than 10

For which of the following is 100 meters a typical service distance? A) 802.11n. B) 802.11g. C) Both A and B D) Neither A nor B

D) Neither A nor B

Two wireless devices communicate via Wi-Fi Direct using ________. A) an access point that lets them talk directly B) an Ethernet network to connect their access points C) Either A or B D) Neither A nor B

D) Neither A nor B

What propagation problem becomes worse as frequency increases? A) Inverse square law attenuation. B) Electromagnetic interference. C) Both A and B D) Neither A nor B

D) Neither A nor B

Which of the following is a draft standard, according to the book? A) 802.11n. B) 802.11g. C) Both A and B D) Neither A nor B

D) Neither A nor B

Which of the following is a full, according to the book? A) 802.11ac. B) 802.11ad. C) Both A and B D) Neither A nor B

D) Neither A nor B

Wider channel bandwidth ________. A) allows more channels to be used in a service band B) decreases transmission speed C) Both A and B D) Neither A nor B

D) Neither A nor B (it increases transmission speed)

Are all devices able to use WPA3? A) Only devices made before 2018 B) Yes, all devices will be able to support WPA3 C) Only devices made after 2014 D) No, most devices will require replacement or firmware update

D) No, most devices will require replacement or firmware update

The 802.11 standard for mesh networking is ________. A) 802.11r B) 802.11m C) 802.11ac D) None of the above

D) None of the above (is 802.11s)

A channel extends from 55 MHz to 60 MHz. Its bandwidth is ________. A) 60 MHz B) 55 MHz C) 65 MHz D) None of the above.

D) None of the above. (5MHz)

The total range of possible 802.11 WLAN frequencies in the 2.4 GHz band constitutes ________. A) a frequency spectrum B) a broadband C) a channel D) a service band E) All of the above.

D) a service band

Channels with wide bandwidths are called ________ channels. A) single-mode B) multimode C) full-duplex D) broadband E) modulated

D) broadband

The frequency range from 500 megahertz to 10 gigahertz is called the ________. A) frequency spectrum B) commercial mobile service band C) UWB region D) golden zone E) unlicensed band

D) golden zone

If two products both comply with 802.11 ac, they should have close to the same performance.

FALSE

In a Wi-Fi LAN, wireless hosts generally send frames directly to one another

False

Nearly all public Wi-Fi hotspots encrypt your transmissions

False

Two WLAN products that conform to the same standard will have almost equal performance. (True or False)

False Will not have equal performance.

Another name for beamforming is having a smart antenna. (True or False)

True.

As a station moves away from an access point, the access point transmits more slowly to it.(True or False)

True.

MIMO allows you to transmit two signals in the same channel. (True or False)

True.

If a wireless client only has two MIMO antennas, an access point with three MIMO antennas will produce better performance than an access point with two MIMO antennas. (True or False)

True

The presence of a client that is distant from the access point reduces the individual throughput of other clients served by that access point. (True or False)

True


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