CIS 285 final exam study guide part 1
The height or power of a wave is known as what? A. Phase B. Frequency C. Amplitude D. Wavelength
Amplitude
Which wave properties can be modulated to encode data? (Choose all that apply.) A. Amplitude B. Frequency C. Phase D. Wavelength
Amplitude, Frequency, and Phase
Which of the following modulation methods are supported with 802.11ac? (Choose all that apply.) A. BPSK B. BASK C. 32-QAM D. 64-QAM E. 256-QAM
BPSK 64-QAM 256-QAM
Which terms describe an 802.11 topology involving STAs but no access points? (Choose all that apply.) A. BSS B. Ad hoc C. DSSS D. Infrastructure E. IBSS F. Peer-to-peer
BSS IBSS Peer-to-peer
Given that an 802.11 MAC header can have as many as four MAC addresses, which types of addresses are not found in an 802.3 MAC header? (Choose all that apply.) A. SA B. BSSID C. DA D. RA E. TA
BSSID RA TA
Which of the following technologies is part of explicit beamforming? (Choose all that apply.) A. Channel sounding B. Feedback matrix C. Sounding matrix D. Steering matrix E. Null data packet F. Channel matrix
Feedback matrix Null data packet Channel matrix
The BSSID address can be found in which topologies? (Choose all that apply.) A. FHSS B. IBSS C. ESS D. HR-DSSS E. BSS
IBSS ESS BSS
The 802.11-2016 standard was created by which organization? A. IEEE B. OSI C. ISO D. Wi-Fi Alliance E. FCC
IEEE
What WLAN client connectivity may be negatively impacted by client load balancing between access points? A. Capacity B. Range C. Roaming D. Throughput E. Security
Roaming
What are the two reasons that 802.11 radios use physical carrier sense? (Choose all that apply.) A. To synchronize incoming transmissions B. To synchronize outgoing transmissions C. To reset the NAV D. To start the random backoff timer E. To assess the RF medium
To synchronize incoming transmissions To assess the RF medium
Which U-NII band proposed by the FCC may provide for 75 MHz of additional spectrum at 5 GHz for Wi-Fi communications? A. U-NII-1 B. U-NII-2A C. U-NII-2B D. U-NII-2C E. U-NII-3 F. U-NII-4
U-NII-4
The Wi-Fi Alliance is responsible for which of the following certification programs? A. 802.11i B. WEP C. 802.11-2016 D. WMM
WMM
23 dBm is equal to how many mW? a. 200 mW b. 14 mW c. 20 mW d. 23mW e. 400mW
200 mW
A wave is divided into degrees. How many degrees make up a complete wave?
360 degrees
What are some examples of how an 802.11 action frame can be used? (Choose all that apply.) A. An action frame can function as a probe request. B. An action frame can function as a neighbor report request. C. An action frame can function as a probe response. D. An action frame can function as a channel switch announcement. E. An action frame can function as a beacon.
An action frame can function as a neighbor report request. An action frame can function as a channel switch announcement.
How many channels should be used in a 5 GHz channel reuse pattern of 20 MHz channels? A. 3 B. 4 C. 8 D. 12 E. As many as available
As many as available
What type of signal is required to carry data? A. Communications signal B. Data signal C. Carrier signal D. Binary signal E. Digital signal
Carrier signal
What components make up a distribution system? (Choose all that apply.) A. HR-DSSS B. DSS C. DSM D. DSSS E. QBSS
DSS DSM
The 802.11ac amendment defines a maximum of how many spatial streams for a client? A. One B. Two C. Four D. Eight
Four
Which sublayer of the OSI model's Data-Link layer is used for communication between 802.11 radios? A. LLC B. PLCP C. MAC D. PMD
MAC
What is the frequency of an RF signal that cycles 2.4 million times per second? A. 2.4 hertz B. 2.4 MHz C. 2.4 GHz D. 2.4 kilohertz E. 2.4 KHz
2.4 MHz
Which frequencies are defined for 802.11n (HT) radio transmissions? (Choose all that apply.) A. 902-928 MHz B. 2.4-2.4835 GHz C. 5.15-5.25 GHz D. 5.25-5.35 MHz
2.4-2.4835 GHz 5.15-5.25 GHz
As defined by the IEEE 802.11-2016 standard, how much separation is needed between center frequencies of channels in the U-NII-2C band? A. 10 MHz B. 20 MHz C. 22 MHz D. 25 MHz E. 30 MHz
20 MHz
When a single-channel OFDM signal is transmitted, what is the approximate frequency width of the transmission? A. 20 MHz B. 22 MHz C. 25 MHz D. 40 MHz E. 80 MHz F. 160 MHz
20 MHz
Which of the following channel widths are supported in 802.11ac? (Choose all that apply.) A. 20 MHz B. 40 MHz C. 80 MHz D. 80+80 MHz E. 160 MHz
20 MHz 40 MHz 80 MHz 80+80 MHz 160 MHz
Assuming all channels are supported by a 5 GHz access point, how many possible 20 MHz channels can be configured on the access point? A. 4 B. 11 C. 12 D. 25
25
What could an 802.11n (HT) radio use to increase throughput at the MAC sublayer of the Data-Link layer? (Choose all that apply.) A. A-MSDU B. A-MPDU C. Guard interval D. Block ACKs
A-MSDU A-MPDU Block ACKs
A WLAN transmitter that emits a 100 Mw signal is connected to a cable with a 3dB loss. If the cable were connected to an antenna with 7dBi of gain, what would be the EIRP at the antenna element? a. 200 mW b. 250 mW c. 300 mW d. 400 mW
250 mW
How many channels should be used in a channel reuse plan for the 2.4 GHz frequency band? A. 3 B. 4 C. 6 D. 11 E. 13
3
A WLAN transmitter that emits 400 mW signal is connected to a cable with a 9 dB loss. If the cable is connected to an antenna with 19dBi of gain, what is the EIRP? a. 4 W b. 3000 mW c. 3500 mW d. 2 W
4 W
2 dBd is equal to how many dBi? a. 5 dBi b. 4.41dBi c. 4.14 dBi d. The value cannot be calculated
4.14
Which management protocols are often used between a network management system (NMS) server and remote access points for the purpose of monitoring a WLAN? (Choose all that apply.) A. IPsec B. GRE C. CAPWAP D. DTLS E. SNMP
CAPWAP and SNMP
Which medium contention and access method is used as the foundation of 802.11 Distributed Coordination Function (DCF)? (Choose all that apply.) A. Carrier Sense Multiple Access with Collision Detection (CSMA/CD) B. Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) C. Token passing D. Demand priority
Carrier Sense Multiple Access with Collision Avoidance
What is the traditional data-forwarding model for 802.11 user traffic when WLAN controllers are deployed? A. Distributed data forwarding B. Autonomous forwarding C. Proxy data forwarding D. Centralized data forwarding E. All of the above
Centralized data forwarding
Which logical plane of network operation is typically defined by protocols and intelligence? A. User plane B. Data plane C. Network plane D. Control plane E. Management plane
Control plane
Which type of access points normally use centralized data forwarding? A. Autonomous APs B. Controller-based APs C. Cooperative APs within a distributed WLAN architecture D. None of the above
Controller-based APs
The presence of what type of transmissions can trigger the protection mechanism within an ERP basic service set? (Choose all that apply.) A. Association of an HR-DSSS client B. Association of an ERP-OFDM client C. HR-DSSS beacon frame D. ERP beacon frame with the NonERP_Present bit set to 1 E. Association of an FHSS client
Association of an HR-DSSS client HR-DSSS beacon frame ERP beacon frame with the NonERP_Present bit set to 1
When an RF signal bends around an object, this propagation behavior is known as what? A. Stratification B. Refraction C. Scattering D. Diffraction E. Attenuation
Diffraction
When calculating the link budget and system operating margin of a point-to-point outdoor WLAN bridge link, which factors should be taken into account? (Choose all that apply.) a. Distance b. Receive sensitivity c. Transmit amplitude d. Antenna height e. Cable loss f. Frequency
Distance - Receive sensitivity - transmit amplitude - Antenna height - cable loss - Frequency
802.11 wireless bridge links are typically associated with which network architecture layer? A. Core B. Distribution C. Access D. Network B. Distribution 4. The 802.11-2016
Distribution
The Wi-Fi Alliance certification called Wi-Fi Multimedia (WMM) is based on which media access method defined by the 802.11-2007 standard? A. DCF B. PCF C. EDCA D. HCCA E. HSRP
EDCA
Which two 802.11 topologies require the use of an AP? A. WPAN B. IBSS C. BSS D. PBSS E. ESS
ESS BSS
Which of the following are included in the topologies defined by the 802.11-2016 standard? (Choose all that apply.) A. DSSS B. ESS C. BSS D. IBSS E. FHSS F. PBSS
ESS BSS IBSS PBSS
The highest RF signal strength that is transmited from an antenna in known as what? a. Equivalent isotopically radiated power b. Transmit sensitivity c. Total emitted power d. Antenna radiated power
Equivalent isotopically radiated power
What is a telecommunications unit of measurement of traffic equal to one hour of telephone traffic in one hour of time? A. Ohm B. dBm C. Erlang D. Call hour E. Voltage standing wave ratio
Erlang
While performing some research, Janie comes across a reference to a document titled RFC 3935. Which org's website would be best to research this document? A. IEEE B. Wi-Fi Alliance C. WECA D. FCC E. IETF
IETF
How many client devices can successfully connect and communicate to an AP? A. 35 B. 50 C. 100 D. 250 E. It depends.
It depends.
Name a capability not defined for A-MPDU. A. Multiple QoS access categories B. Independent data payload encryption C. Individual MPDUs having the same receiver address D. MPDU aggregation
Multiple QoS access categories
Which of the following terms are affiliated with the virtual carrier-sense mechanism? (Choose all that apply.) A. Contention window B. Network allocation vector C. Random back-off time D. Duration/ID field
Network allocation vector Duration/ID field
Which of these 802.11 data frames carry an MSDU payload? (Choose all that apply.) A. Non-QoS data frame B. QoS data frame C. Null frame D. QoS null frame
Non-QoS data frame QoS data frame
What are some of the necessary components of a VoWiFi architecture? (Choose all that apply.) A. VoWiFi phone B. SIP C. WMM support D. Proxy server E. PBX
VoWiFi phone, WMM support, PBX
As defined by WMM, which type of application traffic has the highest priority for transmission on the half-duplex RF medium? A. Best Effort B. Video C. Voice D. Background
Voice
Which term best describes two access points communicating with each other wirelessly while also allowing clients to communicate through the access points? A. WDS B. DS C. DSS D. DSSS E. DSM
WDS
What type of wireless topology is defined by the 802.11-2016 standard? A. WAN B. WLAN C. WWAN D. WMAN E. WPAN
WLAN
Which wireless topology provides citywide wireless coverage? A. WMAN B. WLAN C. WPAN D. WAN E. WWAN
WMAN
What is the recommended received signal and SNR when providing for VoWiFi client communications? A. -70 dBm and 20 dB B. -70 dBm and 25 dB C. -70 dBm and 15 dB D. -65 dBm and 15 dB E. -65 dBm and 25 dB
-65 dBm and 25 dB
How many modulation and coding schemes are defined in 802.11ac? A. 8 B. 10 C. 64 D. 77 E. 256
10
How long do all Wi-Fi radios have to exit a dynamic frequency selection (DFS) channel when a radar pulse is detected? A. 10 seconds B. 30 seconds C. 60 seconds D. 30 minutes E. 60 minutes
10 seconds
To reduce airtime consumption and provide for better capacity in the 5 GHz band, which data rates are recommended to be selected as basic rates? (Choose all that apply.) A. 6 Mbps B. 9 Mbps C. 12 Mbps D. 18 Mbps E. 24 Mbps
12 Mbps 24 Mbps
When the multiple RF signals arrive at a receiver at the same time and are primary wave, the result can be________of the primary signal. A. out of phase, scattering B. in phase, intersymbol interference C. in phase, attenuation D. 180 degrees out of phase, amplification E. in phase, cancellation F. 180 degrees out of phase, cancellation
180 degrees out of phase, cancellation
A wireless bridge is configured to transmit at 100 mW. The antenna cable and connectors produce a 3dB loss and are connected to a 16 dBi antenna. What is the EIRP? a. 20 mW b. 30 dBm c. 2000 Mw d. 36 dBm e. 8 W
2,000 mW
802.11n (HT radios) can transmit in which frequency bands? (Choose all that apply.) A. 2.4 GHz-2.4835 GHz B. 5.47 GHz-5.725 GHz C. 902 GHz-928 GHz D. 5.15 GHz-5.25 GHz
2.4 GHz-2.4835 GHz, 5.15 GHz-5.25 GHz, and 5.47 GHz-5.725 GHz
A WLAN consultant has recommend that a new 802.11n/ac network use only 40 MHz channels in the 5 GHz U-NII bands. Why would he recommend 40 MHz channels be used only in 5 GHz and not in 2.4 GHz? A. HT/VHT radios do not require DFS and TPC in the 5 GHz bands. B. HT/VHT radios get better range using TxBF in the 5 GHz bands. C. 40 MHz channels do not scale in the 2.4 GHz ISM band. D. 5 GHz VHT radios are less expensive than 2.4 GHz HT radios.
40 MHz channels do not scale in the 2.4 GHz ISM band.
Which PHY layer mechanism might be used to increase throughput for an HT/VHT radio in a clean RF environment with minimal reflections and low multipath? A. Maximal ratio combining B. 400-nanosecond guard interval C. Switched diversity D. Spatial multiplexing E. Spatial diversity
400-nanosecond guard interval
A 20 MHz OFDM channel uses how many 312.5 KHz data subcarriers when transmitted by an 802.11a/g radio? A. 54 B. 52 C. 48 D. 36
48
Which of the following are valid U-NII bands? (Choose all that apply.) A. 5.150 GHz-5.250 GHz B. 5.470 GHz-5.725 GHz C. 5.725 GHz-5.85 GHz D. 5.725 GHz-5.875 GHz
5.150 GHz-5.250 GHz 5.470 GHz-5.725 GHz 5.725 GHz-5.85 GHz
In the U-NII-1 band, what is the center frequency of channel 40? A. 5.2 GHz B. 5.4 GHz C. 5.8 GHz D. 5.140 GHz
5.2 GHz
In the United States, 802.11 radios were not allowed to transmit on which range of frequencies in order to avoid interference with Terminal Doppler Weather Radar (TDWR) systems? A. 5.15 GHz-5.25 GHz B. 5.25 GHz-5.25 GHz C. 5.60 GHz-5.65 GHz D. 5.85 GHz-5.925 GHz
5.60 GHz-5.65 GHz
What is the average amount of aggregate throughput at any data rate when legacy 802.11a/b/g/n/ac radios are transmitting? A. 80 percent B. 75 percent C. 50 percent D. 100 percent
50 percent
To double the effective distance of a signal at a specific power level, the EIRP must be increased by how many dBs? a. 3 dB b. 6 dB c. 10 dB d. 20 dB
6 db
How long must an AP listen on a DFS channel before transmitting? A. 10 seconds B. 30 seconds C. 60 seconds D. 30 minutes E. 60 minutes
60 seconds
Which of the following 802.11 frames carry an MSDU payload that may eventually be transferred by the integration service into an 802.3 Ethernet frame? A. 802.11 management frames B. 802.11 control frames C. 802.11 data frames D. 802.11 action frames E. 802.11 association frames
802.11 data frames
STAs operating in the default infrastructure mode may communicate in which of the following scenarios? (Choose all that apply.) A. 802.11 frame exchanges with other STAs via an AP B. 802.11 frame exchanges with an AP in scanner mode C. 802.11 frame peer-to-peer exchanges directly with other STAs D. Frame exchanges with network devices on the DSM E. All of the above
802.11 frame exchanges with other STAs via an AP Frame exchanges with network devices on the DSM
802.11ac (VHT) radios are backward compatible with which of the following types of 802.11 technology? (Choose all that apply.) A. 802.11b (HR-DSSS) B. 802.11a (OFDM) C. 802.11g (ERP) D. 802.11n (HT)
802.11a (OFDM) 802.11n (HT)
Which 802.11 radio technologies are most impacted by the destructive effects of multipath? (Choose all that apply.) A. 802.11a B. 802.11b C. 802.11g D. 802.11n E. 802.11i
802.11a, 802.11b, and 802.11g
802.11n (HT) radios are backward compatible with which of the following types of 802.11 radios? (Choose all that apply.) A. 802.11b radios (HR-DSSS) B. 802.11a radios (OFDM) C. 802.11 legacy radios (FHSS) D. 802.11g radios (ERP)
802.11b radios (HR-DSSS) 802.11a radios (OFDM) 802.11g radios (ERP)
What information that comes from the wired side network is used to assign traffic into access categories on a WLAN controller? A. Duration/ID B. 802.1D priority tags C. Destination MAC address D. Source MAC address
802.1D priority tags
WLAN users have recently complained about gaps in audio and problems with the push-to-talk capabilities with the ACME Company's VoWiFi phones. What could be the cause of this problem? A. A misconfigured TIM setting B. A misconfigured DTIM setting C. A misconfigured ATIM setting D. A misconfigured BTIM setting
A misconfigured DTIM setting
Based on the 802.11 frame capture shown here, which type of networking communication is occurring? A. AP to client station B. Client station to server C. Client station to AP D. Server to client station E. AP to AP
AP to AP
Which keying method is most susceptible to interference from noise? A. FSK B. ASK C. PSK D. DSK
ASK
802.11 technology is typically deployed at which fundamental layer of network architecture? A. Core B. Distribution C. Access D. Network
Access
The EDCA medium access method provides for the prioritization of traffic via priority queues that are matched to eight 802.1D priority tags. What are the EDCA priority queues called? A. TXOP B. Access categories C. Priority levels D. Priority bits E. PT
Access categories
Given: Wi-Fi clients can roam seamlessly at layer 2 if all the APs are configured with the same SSID and same security settings. However, if clients cross layer 3 boundaries, a layer 3 roaming solution will be needed. Which device functions as the home agent if a Mobile IP solution has been implemented in an enterprise WLAN environment where no WLAN controller is deployed? A. Wireless network management server (WNMS) B. Access layer switch C. Layer 3 switch D. Access point on the original subnet E. Access point on the new subnet
Access point on the original subnet
Which is the preferred channel and power configuration method for enterprise WLAN APs? (Choose all that apply.) A. Adaptive RF in standard WLAN environments B. Static channel and power settings in standard WLAN environments C. Adaptive RF in complex RF environments using idirectional antennas D. Static channel and power settings in complex RF environments using directional antennas
Adaptive RF in standard WLAN environments Static channel and power settings in complex RF environments using directional antennas
Which of the following statements regarding the four MAC address fields in the 802.11 MAC header are accurate? (Choose all that apply.) A. Address 2 is always the transmitter address (TA). B. Address 3 is always the transmitter address (TA). C. Address 1 is always the basic service set identifier (BSSID). D. Address 1 is always the receiver address (RA). E. Address 3 is always the basic service set identifier (BSSID). F. Address 2 is always the receiver address (RA).
Address 2 is always the transmitter address (TA). Address 1 is always the receiver address (RA).
What type of interference is caused by overlapping coverage cells with overlapping frequencies? A. Intersymbol interference B. Adjacent channel interference C. All-band interference D. Narrowband interference E. Co-channel interference
Adjacent channel interference
The goal of allocating equal time as opposed to equal opportunity is known as what? A. Access fairness B. Opportunistic medium access C. CSMA/CA D. Airtime fairness
Airtime fairness
What RF technology do IoT client devices use for communication? A. Wi-Fi B. Bluetooth C. Zigbee D. All of the above
All of the above
What are of some of the common security capabilities often integrated within access points deployed in a distributed WLAN architecture? A. Captive web portal B. Firewall C. Integrated RADIUS D. WIPS E. All of the above
All of the above
What are some of the common capabilities of a WLAN controller architecture? A. Adaptive RF B. AP management C. Layer 3 roaming support D. Bandwidth throttling E. Firewall F. All of the above
All of the above
What are some recommendations when using 40 MHz channels in the 5 GHz band? (Choose all that apply.) A. Enable the DFS channels B. Lower AP transmit power C. Verify wall attenuation D. All of the above
All of the above
Which of these WLAN architectures may require the use of an NMS server to manage and monitor the WLAN? A. Autonomous WLAN architecture B. Centralized WLAN architecture C. Distributed WLAN architecture D. All of the above
All of the above
Which of these protocols can be used to manage WLAN infrastructure devices? A. HTTP B. SSH C. SNMP D. Telnet E. HTTPS F. SNMP G. All of the above
All of the above
Which radio form factors can be used by 802.11 technology? A. USB 3.0 B. Secure Digital C. PCMCIA D. Mini PCI E. ExpressCard F. Proprietary G. All of the above
All of the above
Which WLAN architectural models typically require support for 802.1Q tagging at the edge on the network when multiple user VLANs are required? (Choose all that apply.) A. Autonomous WLAN architecture B. Centralized WLAN architecture C. Distributed WLAN architecture D. None of the above
Autonomous WLAN architecture and Distributed WLAN architecture
Using knowledge of RF characteristics and behaviors, which two options should a WLAN engineer be most concerned about during an indoor site survey? (Choose all that apply.) A. Brick walls B. Indoor temperature C. Wood-lath plaster walls D. Drywall
Brick walls and Wood-lath plaster walls
If a station is in power-save mode, how does it know that the AP has buffered unicast frames waiting for it? A. By examining the PS-Poll frame B. By examining the TIM field C. When it receives an ATIM D. When the Power Management bit is set to 1 E. By examining the DTIM interval
By examining the TIM field
Which of the following information is included in a probe response frame? (Choose all that apply.) A. Channel information B. Supported data rates C. Basic data rates D. SSID E. Traffic indication map
Channel information Supported data rates Basic data rates SSID
When deploying a modern 802.11n/ac wireless network with only two access points, which of these 2.4 GHz channel groupings would be considered nonoverlapping? (Choose all that apply.) A. Channels 1 and 3 B. Channels 7 and 10 C. Channels 3 and 8 D. Channels 5 and 11 E. Channels 6 and 10
Channels 3 and 8 Channels 5 and 11
The Barker code converts a bit of data into a series of bits that are referred to as what? A. Chipset B. Chips C. Convolutional code D. Complementary code
Chips
The carrier sense portion of CSMA/CA is performed by using which of the following methods? (Choose all that apply.) A. Contention window B. Backoff timer C. Channel sense window D. Clear channel assessment E. NAV timer
Clear channel assessment NAV timer
What is the main cause of co-channel interference? A. Microwave interference on the same channel within hearing range B. APs on the same channel within hearing range C. APs on a different channel within hearing range D. Clients on the same channel within hearing range E. Clients on a different channel within hearing range
Clients on the same channel within hearing range
What type of interference is a result of APs on the same channel or clients on the same channel hearing each other despite being members of different basic service sets? A. Intersymbol interference B. Adjacent channel interference C. All-band interference D. Narrowband interference E. Co-channel interference
Co-channel interference
What are some potential problems when enabling 40 MHz channels in the 5 GHz band? (Choose all that apply.) A. Adjacent channel interference B. Co-channel interference C. Higher SNR D. Lower SNR E. Decreased range
Co-channel interference Lower SNR
Which two components of the pseudo-random backoff algorithm are used to create the pseudo-random backoff timer? A. Contention window B. Network allocation vector C. Duration/ID D. Slot time
Contention window Slot time
What planes of operation reside in the access points of a distributed WLAN architecture? (Choose all that apply.) A. Radio plane B. Data plane C. Network plane D. Control plane E. Management plane
Data plane and Control plane
At which layer of the OSI model is a BSSID address used? A. Physical B. Network C. Session D. Data-Link E. Application
Data-Link
What term is used to describe the time differential between a primary signal and a reflected signal arriving at a receiver? A. Path delay B. Spread spectrum C. Multipath D. Delay spread
Delay spread
Which field in the MAC header of an 802.11 frame resets the NAV timer for all listening 802.11 stations? A. NAV B. Frame control C. Duration/ID D. Sequence number E. Strictly ordered bit
Duration/ID
Based on RSSI metrics, concentric zones of variable data rate coverage exist around an access point due to the upshifting and downshifting of client stations between data rates. What is the correct name of this process, according to the IEEE 802.11-2016 standard? A. Dynamic rate shifting B. Dynamic rate switching C. Automatic rate selection D. Adaptive rate selection E. All of the above
Dynamic rate switching
A network consisting of clients and two or more APs with the same SSID connected by an 802.3 Ethernet backbone is one example of which 802.11 topology? (Choose all that apply.) A. Public basic service set B. Basic service set C. Extended service set D. Independent basic service set E. Ethernet service set
Extended service set
What is the biggest problem when enabling 5 GHz dynamic frequency selection (DFS) channels? A. Channel switch announcements B. False positives C. Co-channel interference D. Adjacent channel interference E. The 60-second wait time
False positives
Which of the following are valid calculations when using the rule of 10s and 30s? (Choos all that apply.) a. For every 3 dB of gain (relative), double the absolute power (mW). b. For every 10 dB of loss (relative), divide the absolute power (mW) by a factor of 2. c. For every 10 dB of loss (absolute), divide the relative power (mW) by a factor of 3. d. For every 10 mW of loss (relative), multiply the absolute power (dB) by a factor of 10. e. For every 10 dB of loss (relative), halve the absolute power (mW). f. For every 10 dB of loss (relative), divide the absolute power (mw) by a factor of 10.
For every 3 dB of gain (relative), double the absolute power (mW). and For every 10 dB of loss (relative), divide the absolute power (mw) by a factor of 10.
In a normal wireless bridged network, the greatest loss of signal is cause by what component? a. Receive sensitivity b. Antenna cable loss c. Lightning arrestor d. Free space path loss
Free space path loss
Which three properties are interrelated? A. Frequency, wavelength, and the speed of light B. Frequency, amplitude, and the speed of light C. Frequency, phase, and amplitude D. Amplitude, phase, and the speed of sound
Frequency, wavelength, and the speed of light
Which technologies are used by 802.11 radios in the 2.4 GHz ISM band? (Choose all that apply.) A. HT B. ERP C. DSSS D. HR-DSSS
HT ERP DSSS HR-DSSS
What type of communications do 802.11 radios use to transmit and receive? A. Simplex B. Half-duplex C. Full-duplex D. Echo-duplex
Half-duplex
What are the available form factors for network management system (NMS) solutions? (Choose all that apply.) A. Hardware appliance B. Virtual appliance C. Software subscription service D. Integrated access point
Hardware appliance, Virtual appliance, and Software subscription service
A standard measurement of frequency is called what? A. Hertz B. Milliwatt C. Nanosecond D. Decibel E. K-factor
Hertz
Which protocols can be used to tunnel 802.11 user traffic from access points to WLAN controllers or other centralized network servers? (Choose all that apply.) A. IPsec B. GRE C. CAPWAP D. DTLS E. VRRP
IPsec, GRE, CAPWAP
The sum of all the components from the transmitter to the antenna, not including the antenna, is known as what? a. IR b. Isotropic Radiator c. EIRP d. Intentional radiator
IR and Intentional radiator
When data is corrupted by previous data from a reflected signal, this is known as what? A. Delay spread B. ISI C. Forward error creation D. Bit crossover
ISI
What are some of the security capabilities found in an enterprise WLAN router that is typically deployed in remote branch locations? (Choose all that apply.) A. Integrated WIPS server B. Integrated VPN server C. Integrated NAC server D. Integrated firewall E. Integrated VPN client
Integrated firewall and Integrated VPN client
What type of 802.11 radio form factor is normally used in mobile devices such as smartphones and tablets? A. Integrated single chip B. PCMCIA C. Express Mini PCI D. Mini PCI E. Secure Digital
Integrated single chip
The guard interval is used as a buffer to compensate for which type of interference? A. Co-channel interference B. Adjacent cell interference C. RF interference D. HT interference E. Intersymbol interference
Intersymbol interference
A point source that radiates RF signal in all directions is known as what? a. Omnidirectional signal generator b. Omnidirectional atenna c. Intentional radiator d. Nondirectional transmitter e. Isotropic radiator
Isotropic radiator
How does a client station indicate that it is using power-save mode? A. It transmits a frame to the AP with the Sleep field set to 1. B. It transmits a frame to the AP with the Power Management field set to 1. C. Using DTIM, the AP determines when the client station uses power-save mode. D. It does not need to, because power-save mode is the default.
It transmits a frame to the AP with the Power Management field set to 1.
Which 802.11 service set defines mechanisms for mesh networking? A. BSS B. PBSS C. ESS D. MBSS E. IBSS
MBSS
Which 802.11ac MCS range defines all of the MCSs that are mandatory? A. MCS 0-2 B. MCS 0-4 C. MCS 0-6 D. MCS 0-7 E. MCS 0-8 F. MCS 0-9
MCS 0-7
Which of the following contains only LLC data and the IP packet but does not include any layer 2 802.11 data? A. MPDU B. PPDU C. PSDU D. MSDU E. MMPDU
MSDU
What are some objects or materials that are common causes of reflection? (Choose all that apply.) A. Metal B. Trees C. Asphalt road D. Lake E. Carpet floors
Metal, Asphalt road, and Lake
Which HT protection modes would allow only for the association of 802.11a/g clients to an 802.11ac access point? (Choose all that apply.) A. Mode 0—Greenfield mode B. Mode 1—HT nonmember protection mode C. Mode 2—HT 20 MHz protection mode D. Mode 3—HT Mixed mode
Mode 0—Greenfield mode Mode 1—HT nonmember protection mode Mode 2—HT 20 MHz protection mode
The 802.11 standard defines which medium to be used in a distribution system? A. 802.3 B. 802.15 C. 802.5 token ring D. Ethernet E. None of the above
None of the above
Which of these technologies is the most resilient against the negative effects of multipath? A. FHSS B. DSSS C. HR-DSSS D. OFDM
OFDM
Which technology has a greater tolerance of delay spread? (Choose all that apply.) A. DSSS B. FHSS C. OFDM D. HT
OFDM and HT
What is the best example of a time domain tool that could be used by an RF engineer? A. Oscilloscope B. Spectroscope C. Spectrum analyzer D. Refractivity gastroscope
Oscilloscope
Which 802.11 service set is defined specifically for directional multigigabit (DMG) radios? A. BSS B. ESS C. IBSS D. PBSS E. MBSS
PBSS
Which 802.11 service set may allow for client roaming? A. ESS B. BSS C. IBSS D. PBSS
PBSS
The IEEE 802.11-2016 standard defines communication mechanisms at which layers of the OSI model? (Choose all that apply.) A. Network B. Physical C. Transport D. Application E. Data-Link F. Session height power
Physical and Data-Link
During a site survey of a point-to-point link between buildings at a manufacturing plant, the WLAN engineer determines that the noise floor is extremely high because of all the machinery that is operating in the buildings. The engineer is worried about a low SNR and poor performance due to the high noise floor. What is a suggested best practice to deal with this scenario? a. Increase the access points' transmission amplitude b. Mount the access points higher. c. Double the distance of the AP signal with 6dBi of antenna gain d. Plan for coverage cells with a 5 dB fade margin e. Increase the transmission amplitude of the client radios
Plan for coverage cells with a 5 dB fade margin
802.11 collision detection is achieved using which technology? A. Network allocation vector (NAV) B. Clear channel assessment (CCA) C. Duration/ID value D. Receiving an ACK from the destination station E. Positive collision detection cannot be determined.
Positive collision detection cannot be determined.
When a client station is first powered on, what is the order of frames generated by the client station and AP? A. Probe request/response, association request/response, authentication request/response B. Probe request/response, authentication request/response, association request/response C. Association request/response, authentication request/response, probe request/response D. Authentication request/response, association request/response, probe request/response
Probe request/response, authentication request/response, association request/response
CSMA/CA and DCF define which mechanisms that attempt to ensure that only one 802.11 radio can transmit on the half-duplex RF medium? (Choose all that apply.) A. Pseudo-random backoff timer B. Virtual carrier sense C. Collision detection D. Physical carrier sense E. Interframe spacing
Pseudo-random backoff timer Virtual carrier sense Physical carrier sense Interframe spacing
Which modulation types are used by OFDM technology? (Choose all that apply.) A. QAM B. Phase C. Frequency D. Hopping
QAM Phase
Which of the following statements are true about amplification? (Choose all that apply.) A. All antennas require an outside power source. B. RF amplifiers require an outside power source. C. Antennas are passive gain amplifiers that focus the energy of a signal. D. RF amplifiers passively increase signal strength by focusing the AC current of the signal.
RF amplifiers require an outside power source. and Antennas are passive gain amplifiers that focus the energy of a signal.
Which of the following statements are true about free space path loss? (Choose all that apply.) A. RF signals will attenuate as they travel, despite the lack of attenuation caused by obstructions. B. Path loss occurs at a constant linear rate. C. Attenuation is caused by obstructions. D. Path loss occurs at a logarithmic rate.
RF signals will attenuate as they travel, despite the lack of attenuation caused by obstructions. Path loss occurs at a logarithmic rate.
Which value should not be used to compare wireless network cards manufactured by different WLAN vendors? a. Receive sensitivity b. Transmit power range c. Antenna dBi d. RSSI
RSSI
Where is redundancy needed if user traffic is being tunneled in a centralized WLAN architecture? A. Redundant radios B. Redundant controllers C. Redundant access switches D. Redundant access points E. None of the above
Redundant controllers
Which RF behavior best describes a signal striking a medium and bending in a different direction? A. Refraction B. Scattering C. Diffusion D. Diffraction E. Microwave reflection
Refraction
Which of these propagation behaviors can result in multipath? (Choose all that apply.) A. Refraction B. Diffraction C. Reflection D. Scattering E. None of the above
Refraction, Diffraction, Reflection, and Scattering
What percentage of cell overlap is needed to provide for seamless roaming? A. 10 percent B. 15 percent C. 20 percent D. 25 percent E. This is a trick question.
This is a trick question.
WLAN vendors use RSSI thresholds to trigger which radio card behaviors? (Choose all that apply.) a. Receive sensitivity b. Roaming c. Retransmissions d. Dynamic rate switching
Roaming and Dynamic rate switching
What is the default configuration mode that allows an AP radio to operate in a BSS? A. Scanner B. Repeater C. Root D. Access E. Nonroot
Root
ACK and CTS frames follow which interframe space? A. EIFS B. DIFS C. PIFS D. SIFS E. AIFS
SIFS
Which of the following is a better indicator of what outside influences are affecting an RF signal at a specific moment in time a. RSSI b. SNR c. EIRP d. SINR
SINR
Which new power-management method defined by the 802.11n amendment conserves power by powering down all but one radio? A. A-MPDU B. Power Save protection C. PSMP D. SM power save E. PS mode
SM power save
The logical name of an 802.11 wireless network is known as which type of address? (Choose all that apply.) A. BSSID B. MAC address C. IP address D. SSID E. ESSID
SSID ESSID
Which behavior can be described as an RF signal encountering a chain link fence, causing the signal to bounce into multiple directions? A. Diffraction B. Scatter C. Reflection D. Refraction E. Multiplexing
Scatter
After the station has performed the carrier sense and determined that no other devices are transmitting for a period of a DIFS interval, what is the next step for the station? A. Wait the necessary number of slot times before transmitting, if a random back-off value has already been selected. B. Begin transmitting. C. Select a random back-off value. D. Begin the random back-off timer.
Select a random back-off value.
The OSI model consists of how many layers? A. Four B. Six C. Seven D. Nine
Seven
Which of the following can cause refraction of an RF signal traveling through it? (Choose all that apply.) A. Shift in air temperature B. Change in air pressure C. Humidity D. Smog E. Wind F. Lightning
Shift in air temperature, Change in air pressure, Humidity, and Smog
Which carrier sense method is used to detect and decode 802.11 transmissions? A. Network allocation vector B. Signal detect C. Energy detect D. Virtual carrier sense
Signal detect
Physical carrier sense uses which two thresholds during the clear channel assessment to determine if the medium is busy? A. RF detect B. Signal detect C. Transmission detect D. Energy detect E. Random detect
Signal detect Energy detect
Received signal strength indicator (RSSI) metrics are used by 802.11 radios to define which RF characteristics? a. Signal strength b. Phase c. Frequency d. Modulation
Signal strength
MIMO radios use which mechanisms for transmit diversity? (Choose all that apply.) A. Maximal ratio combining (MRC) B. Direct-sequence spread spectrum (DSSS) C. Space-time block coding (STBC) D. Cyclic shift diversity (CSD)
Space-time block coding (STBC) Cyclic shift diversity (CSD)
How can a MIMO system increase throughput at the Physical layer? (Choose all that apply.) A. Spatial multiplexing B. A-MPDU C. Transmit beamforming D. 40 MHz channels
Spatial multiplexing Transmit beamforming 40 MHz channels
What is an example of a frequency domain tool that could be used by an RF engineer? A. Oscilloscope B. Spectroscope C. Spectrum analyzer D. Refractivity gastroscope
Spectrum analyzer
What term best describes a WLAN centralized architecture where the integration service (IS) and distribution system services (DSSs) are handled by a WLAN controller while the generation of certain 802.11 management and control frames is handled by a controller-based AP? A. Cooperative control B. Distributed data forwarding C. Distributed hybrid architecture D. Distributed WLAN architecture E. Split MAC
Split MAC
The 802.11-2016 standard specifies architectural services that stations use within various 802.11 topologies. Which service is used by both client stations and AP stations? A. Station service B. Distribution service C. PBSS control point service D. Integration service E. Bus service
Station service
Hybrid Coordination Function (HCF) defines what allotted period of time in which a station can transmit multiple frames? A. Block acknowledgment B. Polling C. Virtual carrier sense D. Physical carrier sense E. TXOP
TXOP
The WLAN help desk gets a call that suddenly all the legacy 802.11b wireless barcode scanners cannot connect to any of the 802.11n APs. However, all the 802.11g/n clients can still connect. What are the possible causes of this problem? (Choose all that apply.) A. The WLAN administrator disabled the 1, 2, 5.5, and 11 Mbps data rates. B. The WLAN administrator disabled the 6 and 9 Mbps data rates. C. The WLAN administrator enabled the 6 and 9 Mbps data rates as basic rates. D. The WLAN administrator configured all the APs on channel 6.
The WLAN administrator disabled the 1, 2, 5.5, and 11 Mbps data rates. The WLAN administrator enabled the 6 and 9 Mbps data rates as basic rates.
What best describes hop time? A. The period of time that the transmitter waits before hopping to the next frequency B. The period of time that the standard requires when hopping between frequencies C. The period of time that the transmitter takes to hop to the next frequency D. The period of time the transmitter takes to hop through all the FHSS frequencies
The period of time that the transmitter takes to hop to the next frequency
dBi is a measure of what? a. The output of the transmitter b. The signal increase caused by the antenna c. The signal increase of the intentional transmitter d. The comparison between an isotropic radiator and the transceiver e. The strength of the intentional radiator
The signal increase caused by the antenna
When a station sends an RTS, the Duration/ID field notifies the other stations that they must set their NAV timers to which of the following values? A. 213 microseconds B. The time necessary to transmit the Data and ACK frames C. The time necessary to transmit the CTS frame D. The time necessary to transmit the CTS, Data, and ACK frames
The time necessary to transmit the CTS, Data, and ACK frames
What would cause an 802.11 station to retransmit a unicast frame? (Choose all that apply.) A. The transmitted unicast frame was corrupted. B. The ACK frame from the receiver was corrupted. C. The receiver's buffer was full. D. The transmitting station's buffer was full.
The transmitted unicast frame was corrupted. The ACK frame from the receiver was corrupted.
Which of the following statements about scanning are true? (Choose all that apply.) A. There are two types of scanning: passive and active. B. Stations must transmit probe requests in order to learn about local APs. C. The 802.11 standard allows APs to ignore probe requests for security reasons. D. It is common for stations to continue to send probe requests after being associated to an AP.
There are two types of scanning: passive and active. It is common for stations to continue to send probe requests after being associated to an AP.
What are the advantages of using unlicensed frequency bands for RF transmissions? (Choose all that apply.) A. There are no governmental regulations. B. There is no additional financial cost. C. Anyone can use the frequency band. D. There are no rules.
There is no additional financial cost. and Anyone can use the frequency band.
What can you conclude about this frame based on the frame capture graphic shown? (Choose all that apply.) A. This is a unicast frame. B. This is a multicast frame. C. This is a broadcast frame. D. This a transmission between a mesh point AP and a mesh portal AP. E. This frame is encrypted. F. The frame check sequence (FCS) of the previous attempt of the same frame failed at the receiving station.
This is a unicast frame. The frame check sequence (FCS) of the previous attempt of the same frame failed at the receiving station.
Which of the following statements are true about beacon management frames? (Choose all that apply.) A. Beacons can be disabled to hide the network from intruders. B. Time-stamp information is used by the clients to synchronize their clocks. C. In a BSS, clients share the responsibility of transmitting the beacons. D. Beacons can contain vendor-proprietary information.
Time-stamp information is used by the clients to synchronize their clocks. Beacons can contain vendor-proprietary information.
What factors might affect the size of a basic service area (BSA) of an AP? (Choose all that apply.) A. Antenna gain B. CSMA/CA C. Transmission power D. Indoor/outdoor surroundings E. Distribution system
Transmission power Indoor/outdoor surroundings Antenna gain
A 3×3:2 MIMO radio can transmit and receive how many unique streams of data? A. Two B. Three C. Four D. Three equal and four unequal streams E. None—the streams are not unique data
Two
What is the channel and band of a Wi-Fi transmission whose center frequency is 5.300 GHz? A. U-NII-1 channel 30 B. U-NII-1 channel 48 C. U-NII-2A channel 56 D. U-NII-2A channel 60
U-NII-2A channel 56
Which U-NII band is currently designated for Wireless Access in Vehicular Environments (WAVE) communications? A. U-NII-1 B. U-NII-2A C. U-NII-2B D. U-NII-2C E. U-NII-3 F. U-NII-4
U-NII-4
ACKs are required for which of the following frames? A. Unicast B. Broadcast C. Multicast D. Anycast
Unicast
What are some results of multipath interference? (Choose all that apply.) A. Scattering delay B. Upfade C. Excessive retransmissions D. Absorption
Upfade and Excessive retransmissions
WMM is based on EDCA and provides for traffic prioritization via which of the following access categories? (Choose all that apply.) A. WMM Voice priority B. WMM Video priority C. WMM Audio priority D. WMM Best Effort priority E. WMM Background priority
WMM Voice priority WMM Video priority WMM Best Effort priority WMM Background priority
What Wi-Fi Alliance certifications are required before a Wi-Fi radio can be certified as Voice-Enterprise compliant? (Choose all that apply.) A. WMM-Power Save B. Wi-Fi Direct C. WPA2-Enterprise D. Voice-Personal E. WMM-Admission Control
WMM-Power Save, WPA2-Enterprise, and WMM-Admission Control
Which of these capabilities are considered mandatory for an 802.11n access point, as defined by the Wi-Fi Alliance's vendor certification program called Wi-Fi CERTIFIED n? (Choose all that apply.) A. Three spatial streams in receive mode B. WPA/WPA2 C. WMM D. Two spatial streams in transmit mode E. 2.4 GHz-40 MHz channels
WPA/WPA2 WMM Two spatial streams in transmit mode
Which option is a wireless computer topology used for communication between computer devices within close proximity of a person? A. WWAN B. WMAN C. WLAN D. WPAN
WPAN
Select the absolute units of power. (Choose all that apply.) a. Watt b. Milliwatt c. Decibel d. dBm e. Bel
Watt milliwatt dbm
What term best defines the linear distance traveled in one positive-to-negative-to-positive oscillation of an electromagnetic signal? A. Crest B. Frequency C. Trough D. Wavelength
Wavelength
What are some questions that should be considered during WLAN client capacity planning? A. How many users and devices need access currently? B. How many users and devices will need access in the future? C. Where are the users and devices located? D. What are the MIMO capabilities of the client devices? E. What type of applications will be used for the WLAN? F. All of the above
What type of applications will be used for the WLAN?
Which of the following statements are true? (Choose all that apply.) A. When upfade occurs, the final received signal will be stronger than the original trans- mitted signal. B. When downfade occurs, the final received signal will never be stronger than the original transmitted signal. C. When upfade occurs, the final received signal will never be stronger than the original transmitted signal. D. When downfade occurs, the final received signal will be stronger than the original transmitted signal.
When downfade occurs, the final received signal will never be stronger than the original transmitted signal. When upfade occurs, the final received signal will never be stronger than the original transmitted signal.
When is an 802.11ac AP transmitting on 5 GHz required by the IEEE 802.11-2016 standard to respond to probe request frames from nearby client stations? (Choose all that apply.) A. When the probe request frames contain a null SSID value B. When the probe request client is also an 802.11ac radio C. When the probe request is encrypted D. When the probe request has the Power Management bit set to 1 E. When the probe request frames contain the correct SSID value
When the probe request frames contain a null SSID value When the probe request frames contain the correct SSID value
What organization ensures interoperability of WLAN products? A. IEEE B. ITU-R C. ISO D. Wi-Fi Alliance E. FCC
Wi-Fi Alliance
What are the communication differences between Wi-Fi Direct and Wi-Fi CERTIFIED TDLS devices? (Choose all that apply.) A. Wi-Fi CERTIFIED TDLS devices never associate to an AP. B. Wi-Fi Direct devices can communicate with each other without associating to an AP. C. Wi-Fi CERTIFIED TDLS devices remain associated to an AP while communicating directly with each other. D. Wi-Fi Direct devices must associate with an AP before they can communicate with each other.
Wi-Fi Direct devices can communicate with each other without associating to an AP, and Wi-Fi CERTIFIED TDLS devices remain associated to an AP while communicating directly with each other.
Which terms best describe components of a centralized WLAN architecture where the management, control, and data planes all reside in a centralized device? (Choose all that apply.) A. WLAN controller B. Wireless network management system C. Network management system D. Distributed AP E. Controller-based AP
Wlan controller and Controller-based AP
Which of the following wireless communications parameters and usage are typically governed by a local regulatory authority? (Choose all that apply.) A. Frequency B. Bandwidth C. Maximum transmit power D. Maximum EIRP E. Indoor/outdoor usage
all of the above
Select the units of comparison (relative). (Choose all that apply.) a. dBm b. dBi c. Decibel d. dBd e. Bel
dbi decibel dbd bel
Which organization is responsible for enforcing maximum transmit power rules in an unlicensed frequency band?
none of the above
