Take Assessment - Final Exam - Fundamentals of Wireless LANs (Version 1.2)

1 The network administrator wants to ensure that his Aironet bridges are transmitting within the 802.11b WLAN power level of 36 dBm established by the United States FCC. Currently the bridges are transmitting at 25 dBm. The omni-directional antenna results in a 12 dBi gain. The cabling results in a loss of 6.8 dBi per 100 feet of cabling. 25 feet of cabling is installed. What is the EIRP in dB?

34.2

35.3

36.1

36.4

2 During a routine wireless benchmark inspection, the IT personnel of the bank discovered that the AP in the lobby was transmitting at 60

mW. The AP connects to a 6-dBi gain omni-directional antenna through a cable with a 3-dB loss. What is the final power output radiated by the antenna element?

30 mW

60 mW

120 mW

180 mW

3 In a WLAN, what is the purpose of the common DS?

to allow communication between multiple BSSs thereby allowing mobile devices to roam without loss of connectivity

to reduce the number of APs needed to provide reliable connectivity while roaming

to eliminate the need for connectivity to a wired network

to eliminate the need for station addressing when in roaming mode

4Which open standard operating system is licensed for use in many mobile computing devices?

Symbian

MS DOS

Windows XP

OS/2

5 What is the best tool to use if there may be a radio interference problem?

cable tester

gauss meter

spectrum analyzer

time domain reflectometer

6Which type of antenna connectors are used by the Cisco Aironet Bridges?

polarized BNC

reverse TNC

polarized TNC

reverse BNC

7 How wide of a band of frequencies is used by 802.11b DSSS?

5 Mhz

11 Mhz

22 Mhz

24Mhz

8What are the three basic options for configuration on a Cisco Aironet 350 series bridge? (Select three.) (SEM CERTEZA)

Web-browser interface

SNTP

CLI

CDP

SNMP

SSID

9 Which type of antenna is referenced as a base in a dBd rating?

plane

yagi

dipole

isotropic

10dBm is a reference to which unit of measure?

milliWatt

microWatt

Watt

kiloWatt

11 Which command is used to set the parent AP for a repeater AP?

AP(config)# parent 10.0.0.1

AP(config-if)# parent 1 10.0.0.1

AP(config-if)# parent 1 abcd.1234.ab12

AP(config)# parent abcd.1234.ab12

12What frequency or frequencies does the IEEE 802.11 standard utilize?

900 MHz

3.4 GHz

5.4 GHz

2.4 GHz and 5 GHz

900 MHz, 2.4 GHz and 5.4 GHz

13 Access points often have two antennas attached to them for diversity in signal reception. What are two purposes of this diversity? (Select two.)

helps prevent multipath distortion

helps increase signal strength

helps eliminate null coverage areas

helps prevent diffraction and scattering of the signal

14Bit Flipping, Replay Attacks, and Weak IV collection are all considered attacks against which type of security?

WEP

LEAP

PEAP

IPSec

15 In WLAN data transmission, what is the significance of having four different IFS intervals?

to increase the amount of data that can be transmitted at one time

to prevent collisions when accessing the wireless media

to resequence data units at the destination STA

to provide priority levels for access to the wireless media

16 Which types of transmission medium are available for use by WLANs? (Select two.)

fiber-optic

infrared light

UTP

radio frequencies

STP

17What is the difference between higher gain antennas and lower gain antennas? (Select two.)

Higher gain antennas direct energy more precisely.

Higher gain antennas have narrower beamwidths.

Higher gain antennas have a greater chance of receiving interference.

Higher gain antennas have lower bandwidths.

18 When using the site survey tool, a specific mode causes the client adapter to actively send or receive low-level RF packets to and from its associated AP and provides information on the success rate. Which mode accomplishes these functions?

repeater mode

stand-alone mode

passive mode

active mode

parallel mode

19Why do APs have two antennas attached to them?

to increase coverage area

to provide diversity

to provide redundancy

to provide symmetry

20 The ACU site survey tool can operate in which modes? (Select two.)

repeater mode

stand-alone mode

passive mode

active mode

parallel mode

21In DSSS technology, each data bit becomes a chipping sequence. How many chips per bit are used by the IEEE 802.11 standard?

11

12

13

15

22 Cisco Aironet bridges operate at which layer of the OSI model?

physical

data-link

network

transport

23What is the WEP key size specified in the 802.11 standard?

256 bit

64 bit and 128 bit

40 bit and 128 bit

40 bit

24 Which type of threats originate from hackers who are more highly motivated and technically competent?

external

internal

structured

unstructured

25What are the effects of multipath interference? (Select two.)

distorted signals at the receiving end

increased coverage range

poor signal quality levels

enhanced data throughput

incorrect polarization

26 What is the best way to test the line-of-sight path when doing a site-to-site survey?

visually

with a spectrum analyzer

both visually and with a spectrum analyzer

visually and with a Global Positioning System

27Which three power modes are available on a Wireless NIC? (Select three.)

CAM

FastCAM

PSP

FastPSP

FastAPA

28 Which frequency spectrum do FHSS WLANs use in the United States?

83 Mhz around the 5 Ghz ISM band

83 Mhz around the 2.4 Ghz ISM band

900 Mhz around the 5 Ghz ISM band

900 Mhz around the 2.4 Ghz ISM band

29Which two spread spectrum modulation techniques are used by WLANs? (Select two.)

FDSS

ODSS

DSSS

DFSS

FHSS

30 When using high gain omnidirectional antennas, what is helpful in reducing the poor coverage below the antenna?

diversity

polarization

amplifiers

downtilt

31 Which of the following antenna types are used for wireless bridges? (Select three.)

rubber dipole

patch wall

Yagi

Ground Plane

solid dish

32Which of the following antenna types could be used for a point-to-multipoint connection?

patch wall

mast mount

Yagi

solid dish

33 In the United States, how many nonoverlapping channels are there for the 802.11b standard?

three

four

seven

eight

34How does an AP behave when the receive antenna is set to diversity?

It will use the antenna that receives the best signal.

It will use both antennas at the same time.

It will round-robin between the two antennas.

The AP will always use one antenna to transmit and the other to receive.

35

In the graphic, which type of cable should be used at the arrow to protect the WLAN against a direct lightning strike?

coax

fiber-optic

Category 5

UTP

36Which device decodes the various protocol layers in a recorded frame and presents them as readable abbreviations or summaries?

cable tester

network analyzer

spectrum analyzer

time domain reflectometer

37 Which types of software should be installed on laptops to prevent harmful disruptions while they are operating on public wireless networks? (Select two.)

spectrum analyzer

antivirus

firewall

protocol analyzer

repair utility

38What causes the Status LED to blink green in a 1200 series AP?

transmitting/receiving packets

no devices associated

general warning

no special meaning

39 What does a wireless bridge associate with if it is configured as Root=ON?

clients and repeaters only

other Root=ON devices

Master bridge

no device since it is in maintenance mode

40At which OSI layer or layers does a wireless AP operate?

Layer 1

Layers 1 and 2

Layer 2

Layers 2 and 3

41 For a standard survey, how much overlap is sufficient to provide transparent handoffs between APs?

10%

15%

20%

25%

30%

42What is a good antenna to use with an AP to provide coverage for a long indoor hallway?(SEM CERTEZA)

5.2 dBi Ground Plane

8.5 dBi Patch Wall

2.15 dBi Rubber Dipole

2.2 dBi Ceiling Mount

43 Most data collection devices operate at which speed?

1 Mbps

2 Mbps

5 Mbps

11 Mbps

44When a WLAN is being designed to expand an existing LAN, what should be done during the design phase? (Select three.)

Select the carrier.

Learn about the current topology and physical structure.

Study the actual network performance.

Provide an estimation of costs for the new equipment needed.

Identify the links that must be replaced.

45 When configuring the AP Radio Port Hardware setup page, which settings are recommended in situations where communication is poor and many client devices are associating with the access point?

low fragment threshold and high RTS threshold

high fragment threshold and high RTS threshold

high fragment threshold and low RTS threshold

low fragment threshold and low RTS threshold

46 What is the behavior of a wireless bridge when configured as a root bridge?

It associates and communicates with any wireless device on the network.

It associates and communicates only with other root bridges.

It associates and communicates with multiple non-root bridges but only a single root bridge.

It associates and communicates with mrultiple non-root bridges but will not communicate with other root bridges.

47Which topics may be included in the Request for Proposal? (Select three.)

prices and payment options

workstations and servers specifications

an implementation plan

a network topology for the new design

48 What are the keys to maintaining a problem-free network environment and having the ability to isolate and fix a network fault quickly? (Select three).

communication

data backup

documentation

planning

virus protection

fault tolerance

49At which layer of the OSI model do wireless bridges and APs operate?

Layer 4

Layer 3

Layer 2

Layer 1

50 Which statements describe the RF spectrum? (Select two.)

It encompasses both radio waves and microwaves.

Most of the frequencies in the spectrum are unlicensed.

It extends from about 9 MHz to thousands of GHz.

It is used heavily for communications.

The acronym stands for radiated frequency (RF).

51Which of the following statements are correct? (Select two.)

Longer cables lose more power than shorter ones.

Thick cables lose more power than thin ones.

Higher frequencies lose more power than lower ones.

Rigid cables lose more power than flexible ones.

52 In addition to physically installing the client adapter card into the wireless station, what is needed for functionality of the card?

a universal client adapter software driver

an interoperability software patch

a client adapter driver with its corresponding AP driver

a client adapter software driver specific to the OS

53What are the two methods used by wireless clients to connect to an AP according to the IEEE 802.11 standard? (Select two.)

open authentication

shared key authentication

private key authorization

closed authentication

restricted authentication