CNA 170 - Wireless Final - Ch 10 & 11 (Site Survey)
A. Omnidirectional
4. Enterprise office area wireless LAN deployments commonly use ______ antennas for most installations. A. Omnidirectional B. Semidirectional C. Yagi D. Parabolic dish
A. RF coverage & C. RF interference
1. The main objectives of a wireless LAN site survey are to determine ______ and ______. (Choose two.) A. RF coverage B. Cost of equipment C. RF interference D. Manufacturer's equipment E. Which client devices to purchase
B. Number of client devices
10. Which of the following is a main factor in determining the number of access points required for an IEEE 802.11n wireless LAN deployment? A. Type of client devices in use B. Number of client devices C. Manufacturer of client devices D. Antennas in client devices
A. Performance expectations
11. Interviewing managers and users will help determine which part of the site survey process? A. Performance expectations B. Locations of UNII band interference C. Creating floor plans D. Locations of access points
D. Floor plans
12. Which of the following can be imported into a commercial site survey program to assist in predicting the RF coverage of access points? A. Electrical specifications B. Access point models C. Bandwidth requirements D. Floor plans E. Cost estimates
D. Absorption
13. Warehouse inventory such as paint and other liquids in large quantities can cause which RF behavior? A. Reflection B. Refraction C. Diffraction D. Absorption E. Scattering
A. Business requirements & F. Purpose of the wireless LAN
14. You are a wireless LAN consultant contracted to assist in a site survey for a retail outlet that will deploy an 802.11n WLAN. You've been asked to participate in an initial meeting with top management to determine the details of a site survey. What topics would most likely be discussed at this meeting? (Choose two.) A. Business requirements B. Available antenna types C. Recommended manufacturer hardware D. Bill of materials E. Applications in use F. Purpose of the wireless LAN
C. Physical security
15. A wireless LAN will be deployed in a hospital. Which criterion would be addressed when discussing a potential RF jamming attack? A. Data security B. Access point security C. Physical security D. Infrastructure security E. Wiring closet security
B. What are the aesthetic requirements?
16. You are a wireless LAN consultant hired to perform a site survey for a hotel. You need to interview the management and staff regarding the proposed installation of the wireless network. Which of the following is an appropriate question to ask the hotel manager? A. Is PoE used in the hotel? B. What are the aesthetic requirements? C. Which areas lack RF coverage? D. Which areas have RF interference?
A. Applications used
17. Which of the following will be the most likely reason in determining the number of access points required for a wireless LAN deployment? A. Applications used B. Security requirements C. Equipment manufacturer D. Ceiling height
B. Access point output power
18. RF coverage of access points depends on which factor? A. Wiring closet location B. Access point output power C. Electrical power requirements D. Floor plans and blueprints
D. Cost of equipment
19. Which of the following is not a requirement for the initial gathering of technical information for a wireless LAN site survey in a new deployment scenario? A. Number of users B. Applications in use C. Other wireless networks D. Cost of equipment
A. Number of access points
2. What factor usually determines whether a wireless LAN site survey is required? A. Number of access points B. Geographic location of business C. Number of wiring closets D. Number of servers on site
C. Office building
20. Which wireless LAN deployment scenario uses mostly omnidirectional antennas mounted directly to an access point? A. Manufacturing B. Warehousing C. Office building D. Sports arena
C. Gathering business requirements
3. The first step of a wireless LAN site survey is typically ______. A. Determining the RF coverage B. Installing access points C. Gathering business requirements D. Documenting existing networks E. Interviewing managers and users
D. 2.4 GHz ISM band devices
5. You are a wireless network engineer contracted to perform a site survey for a company that manufactures widgets. The wireless site survey will require a physical walk-through of the area. One concern in this implementation is interference from existing ______. A. Wireless 3G internet devices B. Cellular telephones C. 900 MHz two-way radios D. 2.4 GHz ISM band devices E. CB radios
C. Healthcare
6. Implementations that may have existing non-wireless LAN devices that will potentially interfere with a 2.4 GHz wireless LAN deployment most likely fall under what business model? A. Office B. Government C. Healthcare D. Education
C. What applications do you use?
7. You are hired to perform a wireless LAN site survey for a large enterprise company with over a thousand employees. You need to come up with a list of questions to ask users of the wireless network. Which question would be the most relevant for the user community? A. Where are the wiring closets? B. Do you have any floor plans available? C. What applications do you use? D. Do you have an equipment manufacturer preference? E. What is the RF coverage area?
A. Physical & C. Data
8. A wireless LAN site survey and design includes defining ____ and ____security requirements to help protect against RF jamming and protect the integrity of information. (Choose two.) A. Physical B. Access point C. Data D. Device E. Infrastructure
C. Voice handset
9. Which device is the best candidate to use the roaming features of an IEEE 802.11n wireless computer network? A. Notebook computer B. Tablet C. Voice handset D. Wireless camera
A. Areas of RF interference & C. Access point locations
A main objective of a wireless LAN site survey is to determine _____ and _____. (Choose the best two options.) A.Areas of RF interference B.Applications to be used C.Access point locations D.Wiring closet locations E.Security implementations
A. Radio frequency
A spectrum analyzer can be used to view what? A. Radio frequency B. Wireless packets C. Data rates D. Association frames
C. Predictive
A type of site survey that is software-based, requires minimum time on-site, and takes into consideration the attenuation value of materials such as the type of walls and doors is _____. A. Active B. Passive C. Predictive D. Optional
active
A(n) ____________ site survey consists of a survey device such as a notebook computer associating to an access point prior to taking readings and collecting the data.
passive
A(n) _____________ site survey consists of monitoring the air and recording the radio frequency information from all wireless APs &/or devices in the "hearing range" of the surveying station.
A. Channels 1 and 1
Co-channel interference is caused by access points on _____. A. Channels 1 and 1 B. Channels 1 and 2 C. Channels 1 and 6 D. Channels 1, 6, and 11
• General office spaces: Walls and attenuation values • Office cube farms: Density • Medical: Hospitals or medical centers • Industrial: Machine shops or factories • Educational: High quantity of mobile devices
Different environments & some of their distinct type of challenges include:
• Electrical power sources & outlet locations • Existing wiring • Panel information • Existing PoE capabilities
Documentation of the electrical specifications of the environment is helpful in determining whether the current implementation will be sufficient to handle the proposed wireless network deployment. In order to determine whether any upgrades need to be made, (incl PoE upgrade) you will need to gather the following information:
• Monitor air • Record RF info from all devices • Does not require authentication • No traffic passed • Overall snapshot of RF in area • Includes noise and networks
Features of Passive RF site survey:
• Floor plans • Blueprints • Proposed location of furnishings • Electrical specifications
Gathering site-specific documentation that exists for the location, will make a surveyor's job much easier and result in a smoother overall WLAN deployment. Drawings and other documentation pertaining to the following list can provide valuable and time-saving information:
• Existing infrastructure • Future implementations planned • Upgrades • Modifications • Both 802.11 and 802.3 (or other wired networks)
It is critical to know the details of any existing network infrastructure. What information must be documented in regards to existing network infrastructure?
• Signal strength • Signal-to-noise ratio (SNR) • Data rate of connected devices • RF interference
Manual RF Wireless LAN site survey can be very accurate because the surveyor is recording actual statistics, such as:
B. Microwave ovens & D. Cordless phones
Non-Wi-Fi interference for an 802.11g network can be caused by _____ and _____. (Choose two.) A. AM radios B. Microwave ovens C. 802.11b networks D. Cordless phones E. Radar systems F. Digital TV systems
•Physical size of the area •Number of users/devices (including BYOD) •Software or hardware applications in use •Obstacles & propagation factors •Wireless LAN hardware to be used •Output RF power of the transmitters •Receive sensitivity of the receivers
RF coverage and capacity requirements are going to depend on several factors such as:
• Passive & Active surveys • Import floor plans • Often support multiple graphic formats: JPG, BMP, PNG, CAD, etc. • Record critical data - signal & SNR • Visual representation of RF propagation • Postsurvey offline analysis of data
Software-Assisted Manual Site Survey is accomplished using software programs designed specifically for this process. These programs contain many advanced features, including:
• Accurate: Based on actual readings • Physical characteristics of building tested (attenuation values) • Verifies actual RF signal coverage • Mark exact installation locations while on-site
Some advantages of the manual site survey process include:
• Microwave ovens • Cordless telephones • 802.15 devices • Bluetooth, Zigbee, etc. • Medical equipment • Manufacturing/industrial equip • Wireless security cameras • Radar systems (5 GHz bands)
Some common sources of Non-Wi-Fi Interference are:
• Time-consuming • Usually one AP used for testing, so readings must be merged • Requires physical walkthrough of entire location • Many areas require an escort/clearance for access
Some disadvantages of the manual site survey process include:
1. Obtaining floor plan/blueprints of the location 2. Performing a RF spectrum analysis 3. Testing AP placement 4. Taking photos of AP placement with digital camera for documentation 5. Analyzing the site survey results
Some of the basic steps of the Manual site survey process include:
• FHSS networks: 2.4 GHz (Legacy) • DSSS networks: 2.4 GHz • ERP-OFDM networks: 2.4 GHz • OFDM: 5 GHz • HT-OFDM: 2.4 GHz and 5 GHz (802.11n)
Sources of Wi-Fi Interference:
A. Passive & C. Active
The manual site survey consists of which possible methods? (Choose two.) A. Passive B. Scanning C. Active D. Spectrum E. Packet
1. Arrange walkthrough of entire location 2. Take thorough notes (document everything!) 3. Perform RF spectrum analysis 4. Determine preliminary placement of devices (APs, bridges, etc) 5. Perform on-site testing 6. Determine actual placement 7. Install hardware as specified 8. Perform on-site verification testing & adjustments 9. Deliver final report
The process of performing a Physical RF Site Survey is subjective, and there are differing opinions on this process. List the steps/guidelines recommended in the book.
• Size of physical location • Intended use of network • Number of users & devices • Wireless client device capabilities • The wireless LAN environment • Performance expectations • Bring-your-own-device • BYOD acceptance
The scope of the wireless LAN site survey is dependent on many factors, some of which include:
True
True or False: Non-Wi-Fi Interference can be seen via spectrum analysis.
True
True or False: The book recommends that you set the test AP's output power level at about 50% or less during the site survey.
True
True or False: WLAN equipment used in a manual site survey should be from the same manufacturer as the hardware that will be installed in the actual deployment.
D. Manual verification should be performed, but it is not required.
When using a predictive modeling site survey approach, which of the following is true about manual verification? A. Manual verification never has to be performed. B. Manual verification is always required. C. Manual verification should be performed only at the customer's request. D. Manual verification should be performed, but it is not required.
A. Spectrum analyzer & B. Passive scanning utility
What devices, tools, or programs can be used in a manual site survey?(Choose two.) A. Spectrum analyzer B. Passive scanning utility C. Predictive site analyzer D. Association analyzer E. Authentication analyzer
B. Active
When a device associates to an access point during a site survey, it is performing what type of survey? A. Predictive B. Active C. Passive D. Required
D. Yagi
When considering the use of antennas for wireless LAN deployment during a site survey, which antenna could be tested to verify proper coverage for a long hallway or corridor? A. High-gain omnidirectional B. Low-gain omnidirectional C. Parabolic dish D. Yagi
D. Document on the floor plans or blueprints.
When performing a manual site survey, choose the best way to identify areas that lack RF coverage. A. Mark them with tape so they can be located at a later time. B. Use a camera to take a photograph and document it in the report. C. Show the site manager the areas that lack coverage. D. Document on the floor plans or blueprints.
A. Walkthrough of location & E. Spectrum analysis
Which guidelines are recommended when performing a manual site survey? (Choose two.) A. Walkthrough of location B. Predictive analysis C. Equipment purchase D. Client device configuration E. Spectrum analysis
B. It takes less time than a passive survey to get accurate results.
Which of the following is true of a predictive modeling survey? A. It takes more time than a passive survey to get accurate results. B. It takes less time than a passive survey to get accurate results. C. It finds areas of interference from neighboring wireless LANs. D. It helps you choose the manufacturer's equipment to be used for the wireless LAN.
C. -67 dBm
You are a network consultant hired to perform a manual site survey for a small office building. The wireless network to be installed will use data and voice. For backward compatibility, the customer needs to support 2.4 GHz equipment. To provide the highest quality of service for the voice application, you recommend that the received signal strength be a minimum of _____ for a data rate of 54 mbps. A. -20 dBm B. -25 dBm C. -67 dBm D. -76 dBm
D. The channel plan should take all three floors into consideration
You are a network engineer tasked with performing a site survey for a multiple-channel architecture (MCA) system in a three-story building. Which characteristic must be considered while performing a site survey? A. All omnidirectional antennas should be vertically polarized B. Multiple floors require the same channel C Each floor should be treated as an individual site survey D. The channel plan should take all three floors into consideration
B. OFDM
You are performing a protocol analysis in order to determine potential interference from other wireless LANs in the immediate area of the site survey. You discover several wireless LANs that can potentially cause interference with the proposed installation. Which technology in use would not have an impact on the 802.11g wireless network you are surveying for? A. FHSS B. OFDM C. DSSS D. ERP-OFDM E. PBCC
A. Signal strength & B. SNR
You are using a wireless client adapter with a site survey utility and a notebook computer to perform a manual site survey in a very small office building. Which values are important to record to verify proper RF coverage for the location? (Choose two.) A. Signal strength B. SNR C. Packet retries D. Signal loss E. Propagation loss
C. Accuracy
You have been hired by a company to perform a manual site survey. When explaining the difference between a manual and predictive modeling site survey, you let the customer know the advantages and disadvantages of each. A manual site survey has which advantage? A. Speed B. No hardware required C. Accuracy D. Facility access not required
B. Configure the access points to operate in the 5 GHz band.
You have been hired by a company to perform a wireless LAN site survey in a multitenant building. You discover numerous access points on channels 1, 6, & 11. To optimize the new deployment, what recommendation could you make to the customer? (Assume that all new hardware will be purchased and backward compatibility is not required.) A. Configure the access points to automatic channel selection for the 2.4 GHz ISM band. B. Configure the access points to operate in the 5 GHz band. C. Perform a spectrum analysis to find space in the 2.4 GHz band. D. Perform a predictive modeling site survey to determine which channels to use.
D. Correct antenna selection
You need to perform a site survey for a small real estate office that currently has no wireless network. Which factors must be considered as part of the site survey? A. Spectrum analysis B. Packet analysis C. Environmental conditions D. Correct antenna selection
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