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Path to Field Tech I and II (to advance to FT III)
Terms in this set (544)
What is one reason why broadband cable operators install fiber-optic cable in stages instead of changing the infrastructure all at once?
HFC network architectures have been developed to enable broadband cable operators to make a gradual, or staged, transition to an all fiber-optic cable infrastructure.
Which fiber-to-the-x topology has amplifiers in the coaxial cable portion of the network?
Additional RF amplifiers may be in the coaxial cable portion of the fiber-to-the-node (FTTN) topology to maintain proper amplitude levels of the RF signal throughout the serving area.
What topology is used in passive optical network (PON) architectures?
Passive optical network (PON) architectures use fiber-to-the-premises (FTTP) topologies to make point-to-multipoint (P2MP) connections between the broadband cable headend and the customer premises.
What are the three categories of fiber-optic cable in a PON?
The fiber-optic cable in a PON is placed in one of three categories, trunk, branch, and drop, to identify the cable's location in the network
What variations of the star topology are used in PONs?
Centralized split, distributed star, and home-run are variations of the star topology used in PONs.
What does the radio frequency over glass (RFoG) architecture provide as envisioned by broadband cable operators?
RFoG was envisioned to provide operators with the time to make a seamless transition from the legacy hybrid fiber/coax (HFC) architecture over to gigabit PON (GPON) or Ethernet PON (EPON).
What are the three primary elements of a PON?
Using terminology from the telephone industry, the main elements of a PON are the optical line terminal (OLT), the optical distribution network (ODN), and the optical network unit (ONU).
In FTTx networks, what is required to power ONTs at the customer premises?
AC power must be provided at the customer premises in the case of RFoG installations to power the ONT.
What are optical splitters?
Optical splitters are passive branching devices that divide an optical signal across a number of output ports in the forward direction, and combine multiple signals onto a common optical fiber in the return direction.
Why can FTTx applications be more susceptible to the adverse effects of macro- and microbends bends than typical transmission applications?
FTTx standards use some wavelengths that are longer than typical transmission wavelengths, and are therefore more susceptible to the adverse effects of macro- and microbends.
What is the smallest allowable bend radius for G.652 standard single-mode fiber?
The smallest allowable bend radius for G.652 standard single-mode fiber is 30 mm.
Why is it standard industry practice to use pigtail splicing as the preferred method of terminating single-mode fiber?
It is standard industry practice to use pigtail splicing as the preferred method of terminating single-mode fiber because it is faster and more reliable than installing connectors in the field.
What percentage of fiber-optic trouble in the outside plant is caused by people, and what percentage by natural causes?
Statistically, about 75% of fiber-optic troubles in the outside plant are caused by people, almost all occurring during construction or maintenance activities on or near the cable right-of-way. About 25% of trouble is due to natural disasters such as storms and earthquakes.
What are some potential problems in overhead, or aerial, cable installations?
Potential problems in overhead installations include lightning, falling trees and branches, automobile accidents, fire, pole attachment problems, and gunshot and vandal damage.
What are some potential problems in underground cable installations?
Potential problems in underground installations include dig-ups, rodents, ice, improper backfilling, washouts, and landslides.
What equipment should the well-equipped technician have to troubleshoot a fiber-optic system effectively and efficiently?
The well-equipped technician should have a fiber-optic cleaning kit, an optical inspection microscope, an optical power meter, a stabilized light source or an optical loss test set, a visible laser, and an optical time domain reflectometer (OTDR) to effectively and efficiently troubleshoot a fiber-optic system and identify and locate the trouble.
What test equipment would the technician use to identify and locate a localized fiber attenuation problem?
An optical power meter, OTDR, or visible laser could be used to identify and locate a localized fiber attenuation problem.
What is unique about FTTx testing using the optical power meter?
Wavelength-isolating optical power meters are designed to be operated in bi-directional FTTx applications to measure both upstream and downstream ITU-, IEEE-, and SCTE-specified wavelengths.
What is one reason why broadband cable operators install fiber-optic cable in stages instead of changing the infrastructure all at once?
Changing the infrastructure all at once would cause too many service disruptions.
What is the difference between the fiber-to-the-node (FTTN) and fiber-to-the-curb (FTTC) topologies?
An FTTC is allowed a smaller number of RF amplifiers between the optical fiber and the customer premises.
Which of these components is used in a passive optical network (PON)?
Which type of star topology used in a passive optical network (PON) places the PON splitters into fiber access terminal (FAT) located deep in the network and closer to the customer premises than the centralized split?
Which element of a passive optical network (PON) uses a Bragg grating filter?
Optical line terminal (OLT).
Which element of a passive optical network (PON) uses patch panels?
Optical distribution network (ODN).
What is it about radio frequency over glass (RFoG) that made broadband cable operators envision using it to make a seamless transition from the legacy hybrid fiber/coax (HFC) architecture over to a gigabit-capable passive optical network (GPON) or Ethernet passive optical network (EPON)?
RFoG can operate in parallel with GPON or EPON, which eliminates the need for any downtime during the transition.
How are optical splitters used in the forward path?
In the forward path, optical splitters are used as passive branching devices that divide an optical signal across multiple output fibers.
Which of the following describes a fiber pigtail?
Fiber-optic cable with pre-connectorized ends.
Heat shrink tubing is installed over the fusion-splice to strengthen and protect it. When should the heat shrink be installed on the fiber?
Before stripping the plastic coating from the fiber.
What is the sum of each of the following pairs of signed numbers?(a) 4, -3 (b) -5, -10 (c) 3, 6
(4) + (-3) = 1
Find the difference of the following pairs of signed numbers by subtracting the second number from the first.(a) 17, -6 (b) -2, -4(c) 8, 15
(17) - (-6) = 23
Find the product of the following pairs of signed numbers.(a) (-4) × (8) =(b) (-17) × (-11) =(c) (3) × (6) =
(-4) × (8) = -32
Find the quotient of the following pairs of signed numbers by dividing the first number by the second number.(a) ( -48) ÷ (8) =(b) (16) ÷ (4) =(c) (-84) ÷ (-6) =
(a) ( -48) ÷ (8) = -6(b) (16) ÷ (4) = 4
Work the following problems.(a) (20) + (-17) + (-4) =(b) (-18) - (12) =(c) (-24) ÷ (-8) =(d) (28) - (4) × (-9) =(e) (50) + (-28) + (-8) =(f) (-20) + (16) × (-3) =(g) (-7) × (-8) + (9) × (-3) =(h) (-6) × (8) - (8) × (4) =(i) (-12) ÷ (6) + (-5) × (8) =(j) (6) ÷ (-3) + (-4) × (-4) - (-1) × (5) =
(a) (20) + (-17) + (-4) = -1(b) (-18) - (12) = -30(c) (-24) ÷ (-8) = 3(d) (28) - (4) × (-9) = 64(e) (50) + (-28) + (-8) = 14(f) (-20) + (16) × (-3) = -68(g) (-7) × (-8) + (9) × (-3) = 29(h) (-6) × (8) - (8) × (4) = -80(i) (-12) ÷ (6) + (-5) × (8) = -42(j) (6) ÷ (-3) + (-4) × (-4) - (-1) × (5) = 19
Add the following common fractions and state the answer in each fraction's lowest term.
3⁄6 + 3⁄4 =
6⁄7 + 6⁄7 =
27⁄9 + 42⁄3 =
(a) 3⁄6 + 3⁄4 = 6⁄12 + 9⁄12 = 13⁄12 = 11⁄4(b) 6⁄7 + 6⁄7 = 12⁄7 = 15⁄7(c) 27⁄9 + 42⁄3 = 25⁄9 + 14⁄3 = 25⁄9 + 42⁄9 = 67⁄9 + 74⁄9
Subtract the following common fractions and state the answer in the fraction's lowest term.
13⁄5 - 5⁄7 =
24⁄6 - 7⁄9 =
23⁄8 - 6⁄8 =
(a) 13⁄5 - 5⁄7 = 8⁄5 - 5⁄7 = 56⁄35 - 25⁄35 = 31⁄35(b) 24⁄6 - 7⁄9 = 16⁄6 - 7/9 = 48⁄18 - 14⁄18 = 34⁄18 = 116⁄18 = 18⁄9 (c) 23⁄8 - 6⁄8 = 19⁄8 - 6⁄8 = 13⁄8 = 15⁄8
(-25) + (42) + (-62) + (20) =
(17) x (-19) =
(-17) - (-34) =
(20) / (-4) + (-2) x (-10) - (-2) x (7) =
3 6/9 + 6 1/3 + 9 5/9 =
4/7 x 9 4/11 =
7 3/8 divided by 7 1/4 =
wrong answer = 2 1/8
8.13 X 0.123 =
0.5349 divided by 0.1420 =
Define an equation.
We define an equation as a mathematical statement in which two quantities are equal.
To what basic principle does each axiom adhere?
Each axiom adheres to the basic principle that whatever is done must be done to both sides of the equation.
Moving a quantity or term from one side of the equal sign to the other side and changing its sign is called ______________.
Moving a quantity or term from one side of the equal sign to the other side and changing its sign is called transposing.
Which of the following are statements of true axioms?
When A = C and B = C, then A = B because both are equal to C, which supports the axiom: Quantities equal to the same quantity are equal to each other.
Simplify and solve the equation: If E = IR then I = ?
The square of 7 =
The square root of 81 =
0.00004 = ______ x 10 to the power of ______.
(83 x 106) + (27 x 107) =
353 x 106?
10 to the power of -3 has a metric prefix of ______.
(480 x 10 to the power of -5) divided by (60 x 10 to the power of -3) =
8 x 10 to the power of -2
(250 x 10 to the power of -6) - (7 x 10 to the power of -5) =
180 x 10 to the power of -6
(75 × 103) + (25 × 104) =
100 x 10^3
What would be a positive trait associated with being a good troubleshooter?
There are several positive traits associated with being a good troubleshooter; among them are being helpful, loyal, analytical, persistent, and confident.
What might a poor attitude, a poor self-image, or physical and mental exhaustion indicate?
A poor attitude, poor self-image, or physical and mental exhaustion can indicate stress.
What are three long-term practices that can help relieve stress?
To alleviate stress, you can exercise daily, limit your caffeine intake, or develop a support system of friends and relatives.
What are some techniques for managing stress?
Tactics for avoiding and coping with stress overload include: focusing on restoring a positive sense of self; letting go of those things that make you feel bad or overwhelmed by writing them down; dividing tasks into small, bite-size pieces; mentally celebrating each task completion; practicing positive self-talk; noticing negative thoughts; and teaching others how to treat you. Progressive relaxation, using deep breathing and a positive attitude, are also helpful in managing stress. Visualization, meditation, taking a break, and exercising help to de-stress the mind and body and to restore emotional balance.
What kind of obstacle to clear thinking is characterized by thinking about an entire group of people based on personal beliefs about or interactions with one person?
Stereotypical thinking presumes that all members of a group have certain characteristics based on interactions with one member of that group.
Describe the types of questions used in the five Ws method for note taking.
Using the five Ws method of note taking, you might ask questions such as: Who reported the problem? What problem is being reported? When did the problem first occur? Where does the problem occur in the home? Why is the problem occurring?
What does brainstorming for creative thinking entail?
Brainstorming is the act of focusing on a problem, coming up with as many solutions as possible, and then pushing the ideas as far as possible. It is best conducted in a small group with written records of all ideas put forth.
What kind of reasoning is described as moving from a general statement that you know to be true and applying it to a new situation?
Deductive reasoning, also known as top-down logic, can be described as applying an accepted statement (premise) to a new situation.
What are the six steps in the troubleshooting process?
The six steps in the troubleshooting process are:1. Identify the problem2. Analyze the situation3. Isolate the elements4. Diagnose the symptoms5. Resolve the problem6. Verify the solution
Which of the following is a method for controlling expectations?
Identify the source of emotional overload.
Which of the following best describes stereotyped thinking?
Presuming that all members of a group have certain characteristics.
The attribute of being "active" as a critical thinker means
You observe and take notes relevant to the issue.
What kind of reasoning is described as applying a general statement that you know to be true to a new situation?
It is essential to pay attention to warning signs of stress overload. Poor attitude is one of the behaviors that may indicate that you are overstressed. What are the symptoms of poor attitude behavior?
A significant change in attitude with a noticeable movement toward negative, hostile, cynical, or paranoid thoughts.
You are at a customer's home and you are asking the customer whether the problem is intermittent or constant. Which step are you using from the six-step troubleshooting process?
Identifying the problem.
Why should you take the time to take notes and accurately record data at each job location?
Notes and recorded data are tools that can help you accurately remember events at a site that can help you determine a plan of action or evaluate the decisions you made.
You are at a customer's home and you believe you have solved the problem. When you check to be sure the resolution did not introduce any new problems, which step are you using from the six-step troubleshooting process?
Verifying the solution.
To break the habit of a negative self-talk cycle
Tell yourself "not now" and move onto a positive thought whenever negative thoughts occur.
By taking control of the expectations you have, you are
More likely to improve your motivation and be a better problem solver.
How much do you know about successful troubleshooting?
Able to utilize a variety of tools and test equipment..
Persistent and attentive to detail....
Confidentaly execute corrective action(s) to fix a problem...
When troubleshooting a problem, what can be revealed by asking the customer open-ended questions.
When troubleshooting a problem and asking the customer open-ended questions, the customer may reveal that the problem began after some seemingly unrelated work was done inside or outside the premises by other service providers or people that unintentionally damaged the cable.
Which of the six troubleshooting steps can likely be combined and performed at the same time or performed out-of-sequence?
Although troubleshooting is a problem-solving technique that follows a systematic process of analysis, isolation, and diagnostics, these three steps can often be combined and performed at the same time or performed out-of-sequence.
During the isolation step of troubleshooting what method is typically effective?
The divide-and-conquer method (or half-split) is typically employed effectively during the isolation step of troubleshooting.
What are some set-top box (STB)-related troubleshooting calls that can be avoided with customer education?
Blocked IR detector
Bad HDMI cable
Which of the following is data in an out-of-band data channel? Choose all that apply.
Emergency alert system (EAS),,,,,STB authorization,,,,,STB application,,,,,Electronic program guide (EPG)
How much do you know about return path connectivity?
The STB diagnostic can be used to verify set-top box (STB) connectivity with the headend....
The STB controller in the headend instructs the STB to adjust its return channel amplitude levels.....
An output level that is at, or near maximum from the STB can indicate excessive loss in the drop system......
How are the functions of a digital set-top box (STB) like those of a personal computer (PC)?
Many of the functions of a digital STB are like those of a PC with memory for boot-up software, an operating system (OS), graphical interfaces, middleware, and applications software.
What digital set-top box (STB) element sometimes causes the customer to take self-education of the STB features, capabilities, and limitations for granted?
The customer-friendly electronic program guide (EPG) user interface of digital STBs can cause the customer to take self-education of the STB features, capabilities, and limitations for granted.
Why does troubleshooting of digital TV (DTV) service logically revolve around the digital set-top box (STB)?
Because the digital STB functions as a gateway, providing DTV service to customer's TVs and other devices, it is logical that troubleshooting of DTV service revolves around the digital STB.
What is included in digital set-top boxes (STB) to provide product engineers with information pertaining to the STB operation and the channels coming into and leaving the STB?
From the beginning, diagnostic screens have been included in digital STB to provide the product engineers with information pertaining to the STB operation and the channels coming into and leaving the STB.
What prevents authorization of some digital set-top boxes (STB) and ordering of video-on-demand (VOD) content?
Digital TV (DTV) services, such as VOD and authorization of some STBs, require communications with the headend via the RF return path.
A problem that originates during capture and processing
Isolated to one customer
A problem that originates in the drop system
One fiber-node or a specific neighborhood
A problem that originates in the distribution network
For proper operation, what is the specified channel input range to most digital set-top boxes (STB)?
For proper operation, the specified channel input range to most digital STB is -15 to +15 dBmV.
What is added during modulation to quadrature amplitude modulation (QAM) channels that enable digital TV (DTV) receivers to detect and repair data that is lost or corrupted during transport?
During modulation, forward error correction (FEC) data is inserted into the QAM channels to enable DTV receivers to detect and repair data that is lost or corrupted during transport.
Where is a problem that originates during capture and processing of a digital TV channel mostly likely to be observed?
A problem that originates during capture and processing of a DTV channel can be observed throughout the network.
Which of the following characterizes the successful troubleshooter?
Someone with an inquisitive and relentless desire to solve and fix problems.
What must a technician be aware of when analyzing a digital TV (DTV) problem?
There is frequently more than one contributor to a specific DTV service problem.
After a digital TV (DTV) service problem has been analyzed and possible causes considered, what is accomplished by isolating the various network elements?
It narrows the scope of likely problem sources.
During which step of the six-step troubleshooting process for a digital TV (DTV) service problem are quadrature amplitude modulation (QAM) channel measurements typically taken?
When replacing a splitter to resolve a digital TV (DTV) service problem, what does confirming the splitter output levels before attaching the output connectors do?
Confirmation reinforces the technician's confidence that the problem will be resolved by replacing the splitter.
Which of the following digital TV (DTV) trouble calls could have been avoided with customer education about the product?
The digital set-top box (STB) overheats.
When troubleshooting a digital TV (DTV) authorization issue, what can be verified using the set-top box (STB) diagnostic page?
STB reception of authorization message data.
Which type of set-top box (STB) operates more like Data Over Cable Service Interface Specification (DOCSIS) cable modems with return channels on the same frequencies used for cable modems?
STB with DOCSIS Set-top Gateway (DSG) client software and embedded DOCSIS modems.
Because the spectral density of a quadrature amplitude modulation (QAM) channel is much higher than that of an analog TV channel, what is done to ensure equal power in all channels in a network with analog and digital modulation channels?
Operate the analog TV channels at higher amplitude level than the QAM channels.
What does a set-top box (STB) diagnostic page of a quadrature amplitude modulation (QAM) channel showing signal-to-noise ratio (SNR) near or below 30 dB indicate?
The QAM channel quality is on the edge for reliable reception, and the source of the problem is likely in the distribution network or customer premises.
How much do you know about the DOCSIS architecture?
The client (cable modem)/server (CMTS) model is employed in the Data Over Cable Service Interface Specification (DOCSIS) architecture to describe the cable modem termination system (CMTS) and cable modem relationship.
In the DOCSIS architecture, the CMTS is the server.
In the DOCSIS architecture, the cable modem at the customer premises is considered the client.
What are the main components of the DOCSIS architecture?
The main components of the DOCSIS architecture are the cable modem and the cable modem termination system (CMTS).
Which layers of the seven-layer Open Systems Interconnection (OSI) reference model are present in the DOCSIS implementation?
Within the DOCSIS implementation of the OSI model, layers one through four are specific to cable networks and are present only between the cable modem and the CMTS.
Which DOCSIS version provided the option to increase the top frequency of the upstream to 85 MHz, and bumped the downstream range to 108 MHz to 1,002?
DOCSIS 3.0 provided the option to increase the top frequency of the upstream to 85 MHz, and bumped the downstream range from 108 MHz to 1,002 MHz.
What does asymmetric data throughput mean?
Asymmetrical or unequal downstream and upstream data rates are caused by the narrower bandwidth and lower orders of modulation.
if eight QAM channels are bonded, what is the maximum possible downstream throughput?
If eight QAM channels are bonded, the maximum possible downstream throughput is 308 Mbps.
What is the relationship between adjacent orthogonal frequency division multiplexing (OFDM) subcarriers?
OFDM is a transmission scheme in which several independent narrowband carriers (subcarriers) are modulated at a low data rate. The peak power of each subcarrier aligns with the minimum power of the adjacent subcarrier, or orthogonal.
What is the difference between the broadcast and multicast addressing schemes?
Broadcast is a one-to-all addressing scheme in which one device sends the same stream of data to an address that all connected devices can receive. Multicast is a one-to-many communications protocol that simultaneously delivers a single stream of information to multiple addressed devices in a network.
Which of the following are best practices to following when resolving problems in the customer premises? Choose all that apply.
If the throughput between customer's computer and the throughput server is slow, determine whether the problem is in the HFC network between the cable modem and the throughput server, or between the cable modem and the customer's computer...............
When isolating a problem in either the RF distribution network within the customer premises and the customer's local area network (LAN), the logical place to begin is with the modem.
Which step in the six-step troubleshooting process requires a discussion with the customer to gather more detail about the problem?
The first step, identify the problem, requires a discussion with the customer to gather more detail about the problem.
What information should be gathered before beginning to troubleshoot a high-speed data (HSD) problem?
When receiving a work order for an HSD service trouble call, the technician is typically provided with information from a customer service representative (CSR) about the problem.
Where is a logical place to begin applying the divide-and-conquer method to an HSD problem in the customer premises?
HSD service to a customer premises begins at the service tap and terminates in the customer premises equipment (CPE), such as a computer.
What is the value of the cable modem status indicators?
Each indicator can serve multiple purposes during the modem's power-up, initialization, and operation sequences.
Why is a throughput measurement test a valid measurement of a network's performance?
Because throughput can be compromised by traffic congestion and errors introduced during transport, the throughput measurement is an effective measurement of the network's technical integrity.
What can cause the data throughput speeds to vary at different times during the day?
Many factors can contribute to slow throughput such as content delivery network (CDN) speeds, noise or ingress in the broadband network, excessive network traffic, high transmit levels or low receive levels which cause the modem to re-transmit data, or the customer's LAN or computer speed.
Which Data over Cable Service Interface Specification (DOCSIS) layer is used by the cable modem termination system (CMTS) to differentiate between cable modems?
The DOCSIS Media Access Control (MAC) Layer.
What was introduced in Data Over Cable Service Interface Specification (DOCSIS) 3.0 to allow enough bandwidth for upstream carriers from previous DOCSIS versions?
The option to increase the top frequency of the upstream to 85 MHz.
In a Data Over Cable Service Interface Specification (DOCSIS) network, why is the data throughput over the return or upstream path typically less than the throughput of data over the forward or downstream path?
Compared to the downstream path, the narrower bandwidths and lower orders of modulation used to transport data over the return path cause the downstream and upstream data throughput to be unequal or asymmetrical.
What would be the downstream throughput if two quadrature amplitude modulation (QAM) channels with a throughput of 38 megabits per second (Mbps) were bonded?
What are two features that were added in Data Over Cable Service Interface Specification (DOCSIS) 3.1 to extend the viability of hybrid fiber/coax (HFC) networks into the next decade?
Orthogonal frequency division multiplexing (OFDM) and low-density parity-check (LDPC).
How does Internet protocol (IP) multicast differ from IP broadcast?
IP multicast traffic is only sent to specific modem addresses on the network; IP broadcast traffic is sent to all modems on the network.
Which step in the troubleshooting process requires a discussion with the customer to gather more detail about the problem?
Step 1: Identify the problem.
When analyzing a problem, what can the technician learn by asking the customer to show or demonstrate the problem?
The symptoms of the problem can be viewed, and any unusual screens or customer entries can be identified.
When using a digital signal analyzer to troubleshoot data throughput in the Data Over Cable Service Interface Specification (DOCSIS) network, what is the minimum modulation error ratio (MER) into the cable modem for a 256- quadrature amplitude modulation (QAM) carrier?
32 dB or greater
What layers of the Open Systems Interconnection (OSI) reference model are specific to cable networks and are present only between Data Over Cable Service Interface Specification (DOCSIS) modems and the cable modem termination system (CMTS)?
Layers 1 through 4 (Physical layer, Data Link Layer, Network Layer, and Transport Layer) are applied between the DOCSIS modem and CMTS.
How does environmental damage to UTP cable occur?
Environmental damage to UTP cable occurs when system components are subject to water, dirt, oil, sunlight (ultraviolet), air pollution, rodents, and so on.
What are the two types of telephone station wiring typically installed in customer premises?
Quad station wire and unshielded twisted-pair (UTP) cable are the two types of station wire typically installed in customer premises.
How do a short, an open, and a ground fault disrupt dial tone?
A short anywhere in the telephone wiring results in no dial tone to all CPE. An open in the telephone wiring results in selected pieces of equipment having no dial tone, depending on the location of the fault in the circuit and the wiring topology. A ground fault disables the ability of the network or EMTA to supply dial tone.
What circuit condition in the telephone wiring can prevent touch-tone telephones from transmitting the DTMF tones used for tone dialing?
Reverse polarity in the telephone wiring can prevent some touch-tone telephones from transmitting the DTMF tones used for tone dialing.
What are the four most common types of telephone line noise?
The four most common types of telephone line noise are static, hum, crosstalk, and radio interference.
What is the significance of the REN rating when diagnosing a telephone ringer problem?
If the total REN of the telephones, fax machines, etc., connected to one telephone line exceeds the REN of the service, some or all of the ringers may not operate.
How much do you know about cross-pinning and straight-through pinning?
In the configuration cross-pinning, to help maintain polarity throughout the telephone network, the wiring order of the two modular connectors installed on silver satin cable is typically reversed at opposite ends.,,,
In the configuration straight-through pinning, the modular connectors are wired in the same order at both ends of the cable.,....
Straight-through pinning is typically used with 8P8C modular connectors and UTP cable to connect computers and modems to the local area network (LAN).....
When a problem occurs, it is possible to isolate groups of outlets from one another until the group containing the problem is identified using this topology.
Also known as the "loop-through" topology, this topology connects each outlet in series, creating a loop.
If there is a bad connector between the network interface device (NID) and the customer premises equipment (CPE), the problem can be isolated to a single leg and quickly resolved.
What problems can be caused by using a USOC wiring configuration on a modular plug or jack used for data?
Problems caused by using a USOC wiring configuration on a modular data plug or jack include excessive crosstalk, impedance mismatches, and an unacceptable signal delay differential.
Which pinning configuration should be used when 8P8C modular connectors are installed on cables used for connecting computers and modems to the local area network (LAN)?
Straight-through pinning is used when 8P8C modular plugs are installed on cables used for connecting computers and modems to the local area network (LAN).
What are the three major topologies used for unshielded twisted-pair (UTP) cable installations?
The three major topologies for installing UTP cable are the star topology, the bus topology, and the hybrid topology.
How can transposition errors occur?
Transpositions exist when a complete pair of wires are accidentally terminated where another pair should be terminated. This error is typical when an installer terminates one end of an installation in the T568A configuration and the other end in the T568B configuration.
Which of the following is true regarding troubleshooting twisted-pair wiring? Choose all that apply.
When diagnosing premises wiring, if there is voltage present at the NID/EMTA but none at the CPE, then there is a broken wire, an incorrectly wired termination, or a short in one of the connected CPE.,,,,,,
When using the digital multimeter to isolate wiring issues, a shorted modular plug is connected to the wall jack at the opposite end of the cable being tested to verify continuity through the wiring. There should be no connectivity between paired pins until the shorted plug is connected./////
What type of questions should the technician ask the customer during the identify and analyze stages of the six-step troubleshooting process?
During the identify and analyze stage of the six-step troubleshooting process, ask the customer about any work done on the premises and about any unusual events such as power outages or electrical storms prior to the problem, and if anyone has tried to fix the problem already.
What type of test equipment is designed specifically to test and diagnose twisted-pair cable?
The twisted-pair cable tester is designed specifically to test and diagnose twisted-pair cable and its connections.
What are the four major components of a telephone circuit in the customer premises?
The voltage/signal source, consisting of the NID/EMTA, the station wiring, the terminations, such as connectors, plugs, and jacks, and the CPE are the four major components of a telephone circuit in the customer premises.
What should be done if a transposition error is discovered when using a twisted-pair cable tester to locate a fault in a premises that is wired in the star topology?
Inspect the wiring order at the local connector before going to the opposite end and perform the same task. When cabled in the star topology, repeat the same process for each cable by moving the tester remote unit to each room that has a data outlet until all the cables have been tested.
When using a shorted modular plug to verify the connectivity of pairs in UTP cable, which pins on a modular plug breakout adapter should show low resistance on a DMM?
With the shorted modular plug connected, pins 4 and 5 (pair 1), 3 and 6 (pair 2), 1 and 2 (pair 3), and 7 and 8 (pair 4), all should measure near zero ohms of resistance on a DMM.
A customer reports a problem of no dial tone (NDT). Upon inspection, the technician notices that new carpeting has been installed. What should the technician do next?
Look for a cable that runs under the carpet; it is likely that the cable has a short from the carpeting tack strip.
What is the likely problem when there is dial tone on one phone connected to an outlet, but not on two other phones connected to two different outlets?
An open circuit caused by a break in a conductor, poor contact in a modular connector, or an incorrect wire connection.
In the customer premises, what could cause some dual tone multifrequency (DTMF) touch-tone telephones to have continuous dial tone caused by polarity reversal, but not other DTMF telephones?
The telephone wiring polarity is incorrect, and the customer has a mix of older and newer DTMF touch-tone telephones.
What should be checked as a possible cause of hum on a customer's telephone line?
Shielding problems in the station wiring, poor terminations, or poor grounding and bonding connections.
What is the difference between the wiring configurations for a residential, 8-position, 8-contact (8P8C) modular plug and jack in the Universal Service Order Codes (USOC) and ANSI/TIA/EIA 570-B?
The placement of pair numbers 3 and 4.
How is silver satin cable used to connect telephone equipment to wall outlets typically pinned?
Reversed at opposite ends, or cross-pinned.
In unshielded twisted-pair (UTP) cable, what is the term that describes when an information-carrying conductor makes contact with a grounded conductor?
After resolving the problem with the premises wiring issue, which of the following is the next step in the six-step process that the technician should take?
Verify that the problem has been resolved and that phone service is running perfectly on all phones.
If the telephone wiring is in the bus topology and the twisted-pair cable tester is connected at the embedded multimedia terminal adapter (EMTA) with the remote unit connected to the last outlet in the loop, what is the quickest way to locate the incorrectly wired outlet if the tester indicates a wiring error?
Break the loop into smaller sections and retest the two sections to identify which one has the wiring error. Continue to divide the section with the error into smaller sections until the wiring error is identified.
How should the digital multimeter (DMM) be used to troubleshoot problems in the telephone wiring?
Use the voltmeter function; both the network interface device (NID) and the embedded multimedia terminal adapter (EMTA) provide a steady on-hook voltage.
What does 802.11ac use in order to have up to 8 streams?
When setting up a wireless access point, you should do which of the following? (select all that apply)
Enable the SSID and change its name
Use a site survey tool to help locate an unoccupied channel
Change the network key or password
Use WPA2 encryption
[True or False] Wi-Fi Protected Setup (WPS) is a good thing to use on a Wi-Fi network.
Match the class of Bluetooth with its distance rating. Class 1
Match the class of Bluetooth with its distance rating. Class 2
Match the class of Bluetooth with its distance rating. Class 3
What is it called when several computers are sharing files without a WAP?
What is the standard encryption method used with WPA2?
When configuring a wireless router, why is changing the service set identifier (SSID) from the device default recommended?
To avoid telling hackers exactly what the device is.
Which mode uses a wireless access point (WAP) connected to a wired network?
In regard to Wi-Fi networks, what is WPS used for?
To enable connection to a Wi-Fi network without a Windows interface.
Which encryption method is the most secure for a wireless network?
How many channels are available with IEEE 802.11g?
What is the last step of the basic wireless access point (WAP) setup?
All 802.11 standards use one of two frequency bands. What are these frequency bands?
2.4 GHz and 5 GHz bands.
What uses the 2.4-GHz band and runs at 54 Mbps?
Specifies data transfer rates faster than IEEE 802.11 and a more restrictive scope of transmission technologies.
Specifies the lowest data transfer rates.
Using advanced encoding techniques, wider bandwidth channels, and multiple radios, clients can achieve wireless rates as high as 6,913 Mbps.
Specifies data rates higher than, but remains backward compatible with, 802.11b.
Why have WLANs recently grown in popularity?
They provide an inexpensive way to connect buildings on a corporate campus; enable users to build home networks without installing network cables; and save time and money when building new network segments.
What organization creates and maintains the United States WLAN standards?
Institute of Electrical and Electronic Engineers (IEEE) creates and maintains the U.S. WLAN standards.
What organization promotes IEEE 802.11b and later as Wi-Fi?
The Wireless Ethernet Compatibility Alliance (WECA) promotes IEEE 802.11b and later as Wi-Fi.
A manufacturing company needs to connect two networks in buildings located across the street from each other. Which type of building-to-building connectivity is this?
Point-to-point is the building-to-building connectivity.
In larger organizations, where wireless coverage spans large areas, what has significantly increased the productivity of these organizations simply because users remain connected to the network when they are away from their main workstations?
Roaming capability has significantly increased the productivity of these organizations.
What is beneficial when office workers want to share a single Internet connection?
Wireless SOHO devices are especially beneficial when office workers want to share a single Internet connection.
What type of organizations can benefit from using movable networks?
Organizations that can benefit from using movable networks include the Superbowl, the Olympics, circuses, carnivals, fairs, festivals, and construction companies.
Which organization regulates the use of wireless local area network (WLAN) devices in the United States?
The Federal Communications Commission (FCC)
Which of the following Institute of Electrical and Electronics Engineers (IEEE) 802.11 wireless local area network (WLAN) standards specifies both spread spectrum radio frequency (RF) and infrared (IR) transmission technologies?
Why has it become cost-effective for enterprise companies to integrate wireless local area network (WLAN) segments into their networks?
The cost of wireless technology has decreased and the quality has increased.
Which one of the following Institute of Electrical and Electronics Engineers (IEEE) wireless standards utilizes the 5 gigahertz (GHz) frequency band for its signal transmissions?
Why are wireless local area networks (WLAN) usually deployed in an access capacity instead of as the network's core layer?
Wireless LANs are generally incapable of meeting the requirements of the network core layer, which needs to be very fast and stable, able to handle a tremendous amount of traffic with little difficulty, and must experience no down time.
In which Open Systems Interconnection (OSI) reference model layer do wireless local area networks (WLAN) operate?
The Data Link Layer.
What type of connectivity is needed to connect networks between two buildings located across the street from each other?
In which of the following applications might a wireless local area network (WLAN) be deployed in a distribution layer role?
As a building-to-building bridge used to link corporate network segments.
What specific problem does a wireless local area network (WLAN) resolve for corporations and home users?
Excessive data cabling.
What challenges do Wireless Internet Service Providers (WISP) have to overcome in order to provide "last mile data delivery" to customers?
Distance to access points, rooftop access, lightning, trees, mountains, tower access, and other physical obstacles to connectivity.
The term used to describe an increase in an RF signal's amplitude is called _____________
_______________occurs when a propagating electromagnetic wave impinges upon an object that has very large dimensions compared to the wavelength of the propagating wave.
The bending of a radio wave as it passes through a medium of different density is called ______________
When the medium that a wave travels through consists of objects that have dimensions smaller to those of the wavelength of the signal and the number of obstacles per unit volume is large, ______________occurs.
____________ occurs when an RF signal strikes an object and is absorbed into the material of the object in such a manner that it does not pass through, reflect off, or bend around the object.
When can increasing the RF signal's strength have a negative result?
When a transmitter is radiating power very close to the legal power output limit, added power poses a legal problem.
What is used to intentionally inject loss into a circuit?
An RF attenuator is used to intentionally inject loss into a circuit.
What occurs when a surface with sharp irregularities or some sort of rough surface obstructs the radio path between a transmitter and receiver?
Diffraction occurs when a surface with sharp irregularities or some sort of rough surface obstructs the radio path between a transmitter and receiver.
Which of the following is true about VSWR? Choose all that apply.
1- A possible effect VSWR can have on RF circuits is damaged transmitter circuits.
2- To prevent VSWR in a circuit, use impedance-matched cables and connectors.
3- VSWR is the result of an impedance mismatch in an RF circuit.
What is a typical VSWR value?
A typical VSWR value is 1.5:1.
What is one preventative measure against excessive VSWR impedance?
A preventative measure against excessive VSWR impedance is to use high-quality equipment with calibration reports where necessary.
Antennas convert electrical energy into radio frequency (RF) waves in the case of a transmitting antenna, or RF waves into electrical energy in the case of a receiving antenna.
Objects in the Fresnel zone, such as trees, hilltops, and buildings, do not affect the signal.
In most indoor installations, RF signals pass through, reflect off, and refract around walls, furniture, and other obstructions.
Radio frequency line-of-sight (RF LOS) distance is substantially less than visual LOS distance.
Why is the Fresnel zone is important to the integrity of the RF link?
The Fresnel zone is important to the integrity of the RF link because it defines an area around the LOS that can introduce RF signal interference, if blocked.
What is an intentional radiator (IR)?
As defined by the Federal Communication Commission (FCC), an intentional radiator (IR) is an RF device specifically designed to generate and radiate RF signals.
hy is equivalent isotropic radiated power (EIRP) important to understand?
EIRP is important because it is regulated by the FCC and because it is used in calculating whether or not a wireless link is viable.
One thousandth of a watt, and used as a reference point for signal levels at a given point in a circuit.
One ampere (A) of current at one volt (V).
A logarithmic unit describing the relative power levels of electrical and optical signals that is used to measure attenuation, signal quality, reflectance, and amplification.
What is the number for one tenth the power in mW?
-10 dB equals one tenth the power in mW.
An access point transmits at 75 mW. It connects to a 6 dBi gain omnidirectional antenna by means of a cable with -3dB of loss. What is the EIRP in mW?
The EIRP is mW is 150 mW. 6 dBi minus 3 dB = 3 dBi. 3 dB or dBi results in a doubling of power (75 to 150 mW)."
In what manner do radio waves propagate (move) away from the source (antenna)?
In a straight line in all directions at once.
Which one of the following radio frequency (RF) behaviors is defined as "the bending of a wave as it passes through a medium of different density"?
Which of the provided voltage standing wave ratios (VSWR) shown here is best for transferring radio frequency (RF) energy between connections?
What are some measures that can be taken to prevent high voltage standing wave ratios (VSWR) in transmitters and receivers?
Tighten connections between cables and connectors and use impedance-matched hardware throughout.
How does radio frequency line-of-sight (RF LOS) differ from visual LOS?
LOS is accompanied by a Fresnel Zone, a series of concentric ellipsoid-shaped areas around the visual LOS path.
Why is the Fresnel zone important to the integrity of the radio frequency (RF) link or path?
The Fresnel Zone defines an area around the RF line-of-sight (RF LOS) that can introduce RF signal interference if blocked.
What is Equivalent Isotropically Radiated Power (EIRP)?
The The power actually radiated by the antenna element.
What unit of measurement is used to express the gain of an antenna?
Decibels over, or under 1 milliwatt (mW).
Given an access point (AP) with 100 milliwatts (mW) of output power connected through a cable with 3 decibels (dB) of loss to the antenna with a 10 decibels isotropic (dBi) gain, what is the approximate Equivalent Isotropically Radiated Power (EIRP) level from the antenna in mW?
A transmitter outputs 100 milliwatts (mW). An antenna cable connects the transmitter to an amplifier, and the power into the amplifier's input measures 50 mW. The amplifier increases the signal to the original transmitter's power level and sends the signal to the antenna. The antenna receives the signal from the amplifier at 75 mW, and then transmits at 150 mW. What is the intentional radiator's (IR) power level in this radio frequency (RF) circuit?
Uses Bluetooth technology
Wireless personal area network (WPAN)
Connects local area networks (LAN)
Wireless wide area network (WWAN)
Provides communications links between buildings
Wireless metropolitan area network (WMAN)
What is an argument against narrowband transmission?
Narrowband transmission is susceptible to noise, which can overpower the signal.
Which spread spectrum technologies does the FCC describe for use?
The FCC describes direct sequence spread spectrum (DSSS) and frequency hopping spread spectrum (FHSS) for use.
How does spread spectrum technology reduce the probability that a signal will be jammed?
Spread spectrum technology reduces the probability that a signal will be jammed by transmitting over a wider frequency spectrum.
Which of the following is true regarding frequency hopping spread spectrum (FHSS)? Choose all that apply.
1-The FCC defines the maximum dwell time of an FHSS system at 400 ms per carrier frequency in any 30-second period.
2- An FHSS system transmits on a frequency for a specified amount of time, called the dwell time.
Assume that a frequency hopping spread spectrum (FHSS) system hops data across the following set frequency sequence: 2.410, 2.412, 2.422, 2.431, and 2.411 GHz. What will the radio do after it has completed transmission on the last carrier band and has more information to send?
The radio will repeat the hop sequence from the beginning.
Assume that a frequency-hopping spread spectrum (FHSS) system hops data across the following set frequency sequence: 2.410, 2.412, 2.422, 2.431, and 2.411 GHz. If the system experiences interference on the 2.422 GHz band, what will most likely happen to the data?
The data will be retransmitted.
The ratio of the chipping code to data bits for a direct sequence spread spectrum (DSSS) signal is called overhead.
A DSSS signal is less susceptible to narrowband interference than frequency hopping spread spectrum (FHSS) because the DSSS band is much larger.
Users employing IEEE 802.11 DSSS devices do not need to upgrade their entire wireless local area network (WLAN) to use IEEE 802.11b or 802.11g devices on their network.
DSSS systems with overlapping channels should not be co-located because a drastic or complete reduction in throughput almost always occur.
The IEEE first specified the use of direct sequence spread spectrum (DSSS) in the 2.4 GHz Industrial, scientific and Medical (ISM) band with which standards?
The IEEE first specified the use of DSSS in the 2.4 GHz ISM band with 802.11 standards.
Which IEEE draft or standard was the first to introduce technology capable of providing 54 Mbps data rates while remaining backward compatible with 11 Mbps direct sequence spread spectrum (DSSS) systems?
The 802.11g was the first to introduce technology capable of providing 54 Mbps data rates while remaining backward compatible with 11 Mbps DSSS systems.
An advantage of ____________includes a greater resistance to narrowband interference.
_____________ has gained wide acceptance because of its low cost and high speed, and many other factors.
What is an advantage of FHSS over DSSS?
An advantage of FHSS over DSSS is the ability for more FHSS systems to be co-located than DSSS systems.
Which component of an FHSS system creates more overhead than that found in a DSSS system?
The interframe spacing creates more overhead than that found in a DSSS system.
What are three reasons why FHSS systems are no more secure than DSSS systems?
FHSS systems are produced by a limited number of manufacturers, FHSS system manufacturers use a standard set of hop sequences, and FHSS systems transmit the channel number in beacon frames.
Which of the following networks or products use spread spectrum technologies?
Wireless local area networks (WLAN), Bluetooth, and global positioning systems (GPS).
Why is spread spectrum technology used in applications such as Bluetooth wireless personal area networks (WPAN)?
Spread spectrum technology allows wireless networking to create a short range, personal communications network.
In a frequency-hopping spread spectrum (FHSS) system that uses 10 frequencies across a 12 megahertz (MHz) frequency band, what happens if narrowband interference occurs at only one of the 10 frequencies?
The spread spectrum signal remains intact. Instead of being lost, the data on the interfered frequency is retransmitted on one of the other nine frequencies.
The Federal Communications Commission (FCC) rules regarding power output for frequency-hopping spread spectrum (FHSS) state that a maximum output to the intentional radiator (IR) with 5 megahertz (MHz) of carrier frequency bandwidth must be which one of the following?
125 milliwatts (mW).
The ratio of the chipping code to data bits for a direct sequence spread spectrum (DSSS) signal is called which of the following?
Which component of frequency hopping spread spectrum (FHSS) system creates more overhead than any similar component in a direct sequence spread spectrum (DSSS) system?
The interframe spacing.
How does spread spectrum technology reduce the probability of signal jamming?
By transmitting over a wide frequency spectrum.
Although there are many different implementations of spread spectrum technology, what are the only types specified by the Federal Communications Commission (FCC) in the Codes of Federal Regulation (CFR), Volume 47, Part 15?
Direct Sequencing Spread Spectrum (DSSS) and Frequency Hopping Spread Spectrum (FHSS).
Why is direct sequence spread spectrum (DSSS) the most widely known and the most used of the spread spectrum types?
Its ease of implementation and high data rates.
What is the width of direct sequence spread spectrum (DSSS) channels and how far apart are their center frequencies spaced?
22 megahertz (MHz) and 5 MHz.
Which of the following is true about access points (AP)? Choose all that apply.
1- Only use APs in repeater mode when it is absolutely necessary because cells around each AP in this mode must overlap by a minimum of 50 percent.
2-Only a small number of APs on the market provide bridge functionality, which typically adds significant cost to the equipment.
What is an advantage of an AP with a detachable antenna?
An AP with a detachable antenna provides the capability to attach a different antenna to the AP using whatever length of cable that is required.
Why might media access control (MAC) or protocol filtering functionality be included on AP?
Protocol filtering allows an administrator to decide and control which protocols are used across a wireless link.
Why do some manufacturers allow radios to be added to and removed from built-in PC cards or USB slots on APs without removing a cover?
Having two radio slots in an AP allows one radio card to act as an AP while the other radio card acts as a bridge (in most cases a wireless backbone).
The method or methods used to configure and manage APs vary with each manufacturer. What do most brands offer?
Most brands offer at least console, telnet/ssh (secure shell), USB, or a built-in web server for browser access.
Wireless bridges in this mode attach, wirelessly, to wireless bridges that are in root mode.
Wireless bridges in this mode attach, wirelessly, to wireless bridges that are in root mode.
A bridge is positioned between two other bridges for the purpose of extending the length of the wireless bridged segment in this mode.
A useful feature with wireless bridges is ___________________because they provide the ability to mount the bridge indoors and run a cable outdoors to connect to the antenna.
The __________________functionality is useful when performing an outdoor site survey because it allows the site surveyor the flexibility to control the output power without adding and subtracting amplifiers, attenuators, and lengths of cable from the circuit during testing.
variable output power
Where are workgroup bridges (WGB) useful?
WGBs are especially useful in environments with mobile classrooms, mobile offices, or even remote campus buildings where a small group of users need access into the main network.
Which type of wired connectivity ensures that the bridge can be located well beyond the 100-meter physical segment length limit that the Institute of Electrical and Electronic Engineers (IEEE) specifies for unshielded twisted-pair (UTP) cable Ethernet network segments.
100BaseFX connectivity ensures that the bridge can be located well beyond the 100-meter physical segment length limit.
Support plug-and-play (PnP), and often require no additional power other than that delivered through a computer's USB port.
USB client devices
The component that provides the connection between a client device and the network.
Not usually plug-and-play (PnP) compatible and require manual configuration both by means of a DOS-based software utility and configuration of the operating system (OS).
Wireless ISA cards
Used with any device providing Ethernet, USB, or legacy 9-pin serial ports for the purpose of converting those wired connections into WLAN connections.
Ethernet and serial converters
In what two physical formats do manufacturers currently make radio cards?
Personal computer (PC) cards, and compact flash (CF).
What do the profile configuration utilities do?
The profile configuration utilities ease administration tasks considerably when changing from one wireless network to another.
What does the spectrum analyzer utility do?
Spectrum analyzer software finds interference sources and overlapping WLAN channels in the immediate area around a WLAN.
Ethernet switching was added to residential gateways to connect to IEEE 802.11b-, 802.11g-, 802.11n-, and 802.11ac-compliant devices.
Class of service in an enterprise wireless gateway enables the wireless network administrator to assign levels of service to a particular user.
A wireless network administrator should consider installing an enterprise wireless gateway in their network because the enterprise wireless gateway enables the wireless network administrator to manage a large wireless network using only a few central devices instead of a very large number of APs.
Which type of gateway is appropriate for medium-scale and large-scale WLAN environments?
Enterprise wireless gateways are appropriate for medium-scale and large-scale WLAN environments.
Enterprise wireless gateways have role-based access control (RBAC). What does RBAC do?
RBAC allows an administrator to assign a certain level of wireless network access to a particular job position in the company.
What is a big advantage of using enterprise wireless gateways?
Centralized management of only a few devices is one big advantage of using enterprise wireless gateways, which allows an administrator to easily manage a large wireless deployment using only a few central devices instead of a very large number of APs from a single console.
What wireless local area network (WLAN) device can be described as a half-duplex device with intelligence equivalent to that of a sophisticated Ethernet switch?
An access point (AP).
What are some common methods used to configure and manage access points (AP)?
Telnet/ssh (secure shell), USB, and a built in web server for browser access.
What is a half-duplex device that is only capable of Open Systems Interconnection (OSI) reference model Layer 2 (Data Link Layer) connectivity?
A wireless bridge.
Which statement best describes protocol filtering that has been implemented in a wireless bridge?
Allowing or denying wireless traffic using Open Systems Interconnection (OSI) reference model Layer 4 ports to filter Layer 7 applications.
Which statement best describes a network application for which a wireless workgroup bridge is the best suited?
When remote buildings house small groups of wired clients needing wireless access to the main network.
Which wireless client devices require drivers to be installed on the client node?
wireless client devices on printed circuit (PC) cards that are to be installed in peripheral component interconnect (PCI) or industry standard architecture (ISA) adapters.
Residential gateways have been around for quite some time, but what capability was added to connect to Institute of Electrical and Electronics Engineers (IEEE) 802.11b-, 802.11g-, 802.11n-, and 802.11ac-compliant devices?
You are designing a wireless network to which several functional workgroups are connected. You want to configure your enterprise wireless gateway to allow you to quickly assign identical network access rights to persons within the same workgroup. Which enterprise wireless gateway feature provides this capability?
Role-Based Access Control (RBAC).
What security service in an enterprise wireless gateway enables the wireless network administrator to assign levels of service to a particular user?
Class of service (CoS).
Why should a wireless network administrator consider installing an enterprise wireless gateway in their network?
The enterprise wireless gateway enables the wireless network administrator to manage a large wireless network using only a few central devices instead of a very large number of access points.
Used for P2P communication links and can transmit at distances up to 25 miles (42 kilometers), and can connect two buildings that are miles away from each other but have no obstructions in their path.
Highly directional antennas
Used when coverage in all directions around the horizontal axis of the antenna is required and are most effective where large coverage areas are needed around a central point.
Omnidirectional (dipole) antennas
Used for short- and medium-range bridging, such as when two office buildings that are across the street from one another need to share a network connection.
What happens if a dipole antenna is placed in the center of a single floor of a multi-story building?
Most of the dipole antenna's energy is radiated along the length of that floor, with some significant fraction sent to the floors above and below the antenna.
What happens when the electric and magnetic fields are in synchronization with the input signal?
The electric and magnetic fields alternate from minimum through maximum values to form an induction and radiation field.
What results when moisture enters connectors and cables?
Connectors and cables that have any amount of water present will likely produce an erratic RF signal and can cause significant signal degradation because the presence of water changes the cable's impedance, and consequently the voltage standing wave ratio (VSWR).
The____________places a DC voltage onto a CAT-5e cable and may not provide short-circuit or over-current protection.
The__________ provides continuous fault monitoring and protection to detect short circuits and over-current conditions in the CAT-5e cable.
fault protected injector
A_________ takes the DC voltage from the CAT-5e cable and directs it to the equipment through the regular DC power jack for direct connection.
A___________ takes the voltage on the CAT-5e cable and converts it to another voltage.
When is the Power over Ethernet (PoE) delivery method used?
PoE is used when alternating current (AC) power receptacles are not available in the area where wireless local area network (WLAN) infrastructure devices are to be installed.
What types of PoE devices are available?
PoE devices are available in single-port direct current (DC) voltage injectors, multiport DC voltage injectors, and Ethernet switches designed to inject DC voltage on each port on a given pair of pins.
What is one way a fault might be introduced into the CAT-5e cable?
One way a fault might be introduced is through incorrectly wired patch CAT-5e cabling or cut/crushed patch CAT-5e cables in which the insulation on one or more of the conductors have come into contact with each other or another conducting material.
Compensate for signal loss incurred over long RF cables by increasing the signal level before it is injected into the transmitting antenna.
Used in instances where the RF calculations are done ahead of time to ensure the signals are within FCC guidelines.
Fixed-loss RF attenuators
Used in site surveys to aid in coverage pattern discovery and determine antenna gain and necessity of amplifiers.
Boost the effective sensitivity of the receiving antenna by amplifying the received signal before it is fed into the AP, bridge, or client device.
What information should be documented in the system's FCC certificate for RF cables?
If the FCC performs an inspection on a WLAN, which it is authorized to do at any time, it notes the manufacturer, model number, length, and type of connectors on the RF cable.
RF pigtail adapter cables are used for what purpose?
RF pigtails are used to connect cables that have industry-standard RF connectors to manufacturer's WLAN equipment.
What does a frequency converter do?
A frequency converter modifies or changes one frequency range into another to decongest a frequency band, and is common for many companies located in the same multitenant office building to have WLANs.
How is a test kit used in WLANs?
A test kit consisting of an RF signal generator and a through-line power meter can be used to check the cable and connections between an IR and an antenna.
In what direction does an omnidirectional antenna radiate radio frequency (RF) energy?
Equally in all directions around its axis.
What is a consideration when mounting a high-gain omnidirectional antenna indoors on the ceiling?
If the ceiling is too high, the coverage area might not reach the floor where the users are located.
As a general rule, how does an increase in effective isotropic radiated power (EIRP) relate to the link budget range?
Each 6 decibels (dB) increase in EIRP equates to a doubling of range.
What happens when an active Ethernet switch fails to sense a power over ethernet PoE device on a port.
It switches off the direct current (DC) voltage on that port.
Which statement describes a passive injector?
it places direct current (DC) voltage onto a CAT-5e cable.
What power over Ethernet (PoE) device picks off the direct current (DC) voltage that has been injected into the CAT-5e cable by the injector and makes it available to the equipment through the regular DC power jack?
A DC picker or tap.
What device would a wireless local area network (WLAN) administrator install between the access point (AP) or bridge and the network to give indoor local area network (LAN) users as much bandwidth as possible?
A bandwidth control unit (BCU).
Polarization is defined as which one of the following?
orientation of an electromagnetic wave's electric field in relationship to the Earth's surface or plane.
What is the typical coverage pattern of semi-directional antenna?
A hemispherical or cylindrical pattern.
What antenna type is ideal for making a point-to-point (P2P) network connection between two office buildings that are across the street from one another?
A semi-directional antenna.
Has lost favor to higher frequency systems because the devices are becoming obsolete and expensive to replac
900 MHz ISM band
Overlaps part of another license-free band, the upper U-NII band.
5.8-GHz ISM band
Used by all Bluetooth® and IEEE 802.11-, 802.11b-, 802.11g-, and 802.11n-compliant devices.
2.4 GHZ ISM band
What does the IEEE specify as the maximum allowable power output for 802.11a, 802.11n, and 802.11ac devices operating on the lower U-NII band?
The IEEE specifies 40 mW as the maximum allowable power output for 802.11a, 802.11n, and 802.11ac devices operating on the lower U-NII band.
Which 802.11 standard uses all three U-NII bands?
The 802.11ac standard uses all three U-NII bands.
What links include a single directional transmitting antenna and a single directional receiving antenna?
P2P links include a single directional transmitting antenna and a single directional receiving antenna.
IEEE____________specifies data rates of only 6, 12, and 24 Mbps.
IEEE________ devices achieve 802.11a data rates by switching from QPSK to OFDM.
Infrared is defined in the ________ IEEE standard.
IEEE____________is referred to as "high-rate" and Wi-Fi®, and specifies DSSS systems that operate at 1, 2, 5.5, and 11 Mbps.
What technology does 802.11n and 802.11ac employ to help provide dramatic improvements in reliability, throughput, and operating range?
IEEE 802.11n and 802.11ac employ multiple-input multiple-output (MIMO) technology to help provide dramatic improvements in reliability, throughput, and operating range.
What allows subsets of subcarrier paths to be assigned to single users, enabling simultaneous low-bit rate concurrent transmissions from multiple users?
Orthogonal frequency-division multiple access (OFDMA) allows subsets of subcarrier paths to be assigned to single users, enabling simultaneous low-bit rate concurrent transmissions from multiple users.
Promotes and tests for WLAN interoperability of 802.11 devices.
European Telecommunications Standards Institute (ETSI)
The mission of this organization is to educate and raise consumer awareness regarding the use and availability of WLANs, as well as to promote the WLAN industry in general.
Certified Wireless Network Professionals (CWNP)
Promotes and tests for WLAN interoperability of IEEE 802.11 devices
You are building a wireless network segment that will carry voice over Internet protocol (VoIP) traffic. You want to supply quality of service (QoS) to the voice traffic. Which one of the following standards supports QoS awareness?
European Telecommunications Standards Institute (ETSI) HiperLAN/2 promotes QoS awareness.
You are looking for backwards compatibility information concerning a particular wireless product or service. Which organization will you contact?
Certified Wireless Network Professionals (CWNP) is the organization to contact.
Which of the following is true about Bluetooth technology? Choose all that apply.
1-A major disadvantage of using Bluetooth technology is that it tends to completely disrupt other 2.4-GHz networks.
2-To IEEE 802.11 networks operating in the 2.4 ISM radio bands, Bluetooth transmissions appear as all-band noise.
3-The maximum range of Class 2, 2.5 milliwatt (mW), Bluetooth devices is 10 meters or 33 feet.
You are designing a wireless network that will support users working in a single room. The network must protect data from interception, and not be susceptible to interference from existing direct sequence spread spectrum (DSSS) networks. Which technology meets these requirements?
Infrared technology meets these requirements.
Which wireless technologies utilizes frequency hopping?
Bluetooth utilizes frequency hopping.
What is the hop rate for Bluetooth devices?
The hop rate for Bluetooth devices is 1600 hops per second (hps).
Why have 900 megahertz (MHz) Industrial, Scientific, and Medical (ISM) band wireless local area networks (WLAN) lost favor in comparison to 2.4 gigahertz (GHz) and 5 GHz frequency systems?
900 MHz devices are more expensive and provide slower data throughput.
What is the Federal Communications Commission (FCC) regulation for the maximum ERIP from a point to multipoint (P22P) wireless local area network (WLAN) antenna?
4 watts (W).
Operation as an IEEE 802.11ac device occurs only in the 5 gigahertz (GHz) Unlicensed National Information Infrastructure (U-NII) radio band, so how are 802.11ac devices able to maintain compatibility with earlier standards that operate in the 2.4 GHz Industrial, Scientific, and Medical (ISM) radio bands?
IEEE 802.11ac devices also operate in the 2.4 GHz ISM range.
Which of the following statements is true concerning bluetooth technology ?
To IEEE 802.11 networks operating in the 2.4 Industrial, Scientific, and Medical (ISM) radio bands, Bluetooth transmissions appear as all-band noise.
What is the maximum range of Class 2, 2.5 milliwatt (mW), Bluetooth devices?
10 meters or 33 feet.
Bluetooth uses which spread spectrum technology?
Frequency-hopping spread spectrum (FHSS).
Bluetooth is a short range wireless personal area network (WPAN) technology that is covered under which Institute of Electrical and Electronics Engineers (IEEE) standard?
What technologies does the IEEE 802.11n wireless standard use to achieve data rates as high as 600 megabits per second (Mbps)?
Multiple input, multiple output (MIMO) technology and spatial multiplexing.
What does the Institute of Electrical and Electronics Engineers (IEEE) specify as the maximum allowable power output into the intentional radiator for IEEE 802.11a-, 802.11n-, and 802.11ac-compliant devices operating on the lower Unlicensed National Information infrastructure UNII radio band?
How wide is each of the three WLAN UNII bands?
What is the most important point about an SSID when connecting to a WLAN?
The most important point is that the SSID must match exactly between APs and clients.
What are beacons?
Beacons are short frames sent from the AP to stations (in infrastructure mode) or from station-to-station (in ad hoc mode) to organize and synchronize wireless communication on the WLAN.
What is passive scanning?
Passive scanning is the process of listening for beacons on each channel for a specific period of time after the station is initialized.
What is active scanning?
Active scanning involves sending a probe request frame from a wireless station when they are actively seeking a network to join.
Which of the following is true about authentication and association when connecting to a wireless local area network (WLAN)? Choose all that apply.
1- The WEP security key is used during the shared key authentication process to verify a client's identity, and it is also used for encryption of the data payload sent by the client through the AP.
2- VPN is commonly used to link remote computers or networks to a corporate server by means of the Internet.
What is authentication?
Authentication is a process in which a wireless node has its identity verified by the network (usually the AP) where the node is attempting to connect.
What is association?
Association is the state at which a client may pass data through an AP.
What happens in the final state of authentication and association?
The wireless node is completely connected to the network and able to send and receive data through the AP to which the node is connected (associated).
What should be done since shared key authentication and open system types are not secure?
A WLAN security solution that is above and beyond what the IEEE 802.11 standard specifies should be utilized.
Has no AP or any other access to a distribution system, but it covers one single cell and has one SSID.
Independent basic service set
Two or more basic service sets connected by a common distribution system.
Extended service set
The type of network connection when one AP is connected to a wired network and a set of wireless stations.
Basic service set
What do roaming clients use to gauge the strength of their existing connection to the AP?
Roaming clients use the beacon to gauge the strength of their existing connection to the AP. If the connection is weak, the roaming station can attempt to associate itself with a new AP.
What happens when an IEEE 802.11 client enters the range of two or more APs?
When an IEEE 802.11 client enters the range of two or more APs, the client chooses an AP to associate with (also called joining a BSS), based on signal strength and observed bit error rates.
When a mobile device reattaches to the network, all application end points are lost, and users are forced to log in again, reauthenticate, relocate themselves in their applications, and recreate lost data. What is a solution to this problem?
A hardware solution to this problem is to deploy all APs on a single VLAN using a flat IP subnet for all APs so that no change of IP address for roaming users occurs, and a mobile IP solution is not required.
What happens in a multicell structure?
In a multicell structure, multiple co-located APs "illuminate" the same area, creating a common coverage area, which increases aggregate data throughput.
While CAM is the always-on modem, which mode allows a wireless client to conserve battery power by "sleeping" for a short time period?
PSP mode allows a wireless client to conserve battery power by "sleeping" for a short time period.
Computers that are continuously plugged into an AC power outlet, such as a desktop or server, should always be set for which mode?
Computers that are continuously plugged into an AC power outlet should always be set for CAM.
What is different about an IBSS from a BSS?
In an IBSS, every station must buffer frames destined from itself to every other station in the ad hoc network.
The attacker replaces the victim's wireless device to the AP, then continues the banking or shopping transactions currently in progress by the victim, or may continue surfing the web as that person.
The attacker eavesdrops or snoops on an unencrypted wireless session to intercept the victim's session cookie.
The attacker gathers unencrypted wireless packets as they move between the client device and the AP.
A second AP with the same SSID is deployed at a legitimate hotspot location like a coffee shop, airport, or hotel.
Evil twin attack
What signals the subscriber's mobile wireless device of an available Wi-Fi network when the subscriber enters a hotspot area?
The AP advertises to the wireless device to enable connection.
What is the GAS?
The GAS is an OSI reference model Data Link Layer (Layer 2) transport where the client queries the AP for information before authentication takes place.
When connecting to a wireless local area network (WLAN), what is the most important point about the service set identifier (SSID)?
That the clients and all access points (AP) must be configured with matching SSIDs.
How does a client locate a wireless local area network (WLAN) when performing passive scanning?
The client listens for beacons until it hears a beacon listing the service set identifier (SSID) of the network it expects to join.
Why would a wireless local area network (WLAN) administrator rarely see the "authenticated" step on the access point (AP)?
Because clients pass the authentication stage and immediately proceed into the association stage.
Why is shared key authentication considered a security risk in a wireless local area network (WLAN)?
The AP transmits the challenge text in the clear and receives the same challenge text encrypted with the WEP key.
An independent basic service set (IBSS) is also commonly referred to as which one of the following?
Ad hoc network.
What does a basic service set (BSS) consist of?
A BSS consists of one access point (AP) and one or more wireless clients.
Which term describes the operation mode of a basic service set (BSS)?
In a segmented wireless local area network (WLAN) that has a different Internet protocol (IP) address for each segment, which solution allows mobile clients to maintain their connectivity when roaming into different segments?
To deploy all access points (AP) on a single virtual local area network (VLAN) using a flat IP subnet for all APs so that no change of IP address for roaming clients occurs and all traffic goes through a central controller.
Which one of the following power management modes populates a traffic indication map (TIM) in a basic service set (BSS) or extended service set (ESS)?
Power save polling (PSP) mode.
As a subscriber enters a hotspot area, what signals their mobile wireless device of an available Wi-Fi network?
The access point (AP) queries all wifeless devices that come within range of their availability for connection.
When an Ethernet network becomes congested, can cause overhead of up to 70 percent.
Increased the amount of control data used in WLANs by creating overhead that uses approximately 50 percent of the available bandwidth on a WLAN.
Avoids collisions and uses positive ACKs
Generates overhead on only about 30 percent on an average network.
Avoids the probability of collisions among stations sharing the medium by using a random back off time when a station's physical or logical sensing mechanism indicates a busy medium.
Used after the collisions occur.
True or False? During fragmentation, smaller packets have a higher probability of collisions on the network.
An access method that allows all stations on a WLAN to contend for access on the shared transmission medium (RF) using the CSMA/CA protocol is ________.
A transmission mode that allows for contention-free frame transfers on a WLAN by making use of a polling mechanism is ___________.
______________is never implemented in a standalone fashion; rather, it is implemented in such a way that both clients configured for DCF mode and PCF mode are supported simultaneously.
What is the maximum frame size of IEEE 802.11 WLANs?
IEEE 802.11 WLANs have a maximum frame size of 2,346 bytes.
To prevent unnecessary overhead from being introduced into the network, how do stations fragment?
Stations only fragment unicast frames, and never multicast and broadcast frames.
How does the speed adjustment occur using dynamic rate shifting (DRS)?
The speed adjustment occurs as distance increases between the client and the AP, or as interference increases.
The longest fixed interframe space and is used by default on all IEEE 802.11-compliant stations that are using the DCF mode.
Distributed Coordination Function Interframe Space (DIFS)
Provides the highest level of priority network function control over the medium for a short time period.
Short Interframe Space (SIFS)
Only works with DCF, not as a stand-alone operational mode so that, once the AP is finished polling, other stations can continue to contend for the transmission medium using DCF mode.
Point Coordination Function (PCF)
How are interframe spaces meausred?
Interframe spaces are measured in microseconds (µs) and are used to defer a station's access to the medium and provide various levels of priority.
What is a slot time?
A slot time, which is preprogrammed into the radio in the same fashion as the SIFS, PIFS, and DIFS timeframes, is a standard period of time on a wireless network.
The superframe only occurs when what conditions are met?
The superframe only occurs when 1) the network is in PCF mode, 2) the AP has been configured to do polling, and 3) the wireless clients have been configured to announce to the AP that they can be polled.
Using the RTS/CTS protocol allows wireless stations to do which of the following?
The RTS/CTS allows stations to broadcast their intent to send data across the network.
Typically, RTS/CTS should only be used in diagnosing network problems and when large frames are flowing across a congested wireless network. What other reasons should RTS/CTS be set?
Because collisions affect larger frames more than smaller ones, the RTS/CTS threshold can be set to work only when a node wishes to send frames over a certain size.
What are the types of modulation used by IEEE standards 802.11, 802.11b, and 802.11g products?
Differential binary phase shift keying (DBPSK), differential quadrature phase shift keying (DQPSK), and Gaussian frequency shift keying (GFSK) are the types of modulation used by IEEE standards 802.11, 802.11b, and 802.11g products.
What happens when higher transmission speeds are specified, such as when a system is using dynamic rate shifting (DRS)?
Modulation techniques change to provide more data throughput.
Which is the largest IEEE 802.11 data frame that can traverse a wireless local area network (WLAN) without fragmentation?
What is the tradeoff between the fragmenting of packets into shorter fragments versus keeping longer packet fragments?
Shorter packet fragments have lower probability of errors from interference than longer packet fragments, but shorter packet fragments require more error correction.
Which type of interframe space provides the highest level of priority network function control over the medium for a short time period?
Short Interframe Space (SIFS).
How are interframe spaces used in an Institute of Electrical and Electronics Engineers (IEEE) 802.11 wireless local area network (WLAN)?
They are used to defer a station's access to the medium and provide various levels of priority.
What is a slot time in an Institute of Electrical and Electronics Engineers (IEEE) 802.11 wireless local area network (WLAN)?
A standard period of time on a WLAN in which packets are inserted.
What is the purpose of the Institute of Electrical and Electronics Engineers (IEEE) 802.11 wireless local area network (WLAN) superframe?
To allow fair coexistence between point coordination function (PCF)-mode and distributed coordination function (DCF)-mode clients on the network.
When should you consider enabling Request to send/clear to send (RTS/CTS) protocol on a wireless local area network (WLAN)
When diagnosing network problems and when large frames experience high collision rates across a congested wireless network.
What does the "on with threshold" setting of the Request to send/clear to send (RTS/CTS) protocol allow the wireless local area network (WLAN) administrator to control?
To control how often frames are announced and cleared to send by the stations.
What modulation technique does Institute of Electrical and Electronics Engineers (IEEE) wireless local area network (WLAN) standards 802.11a, 802.11n, and 802.11ac use to achieve higher data throughput?
Differential quadrature phase shift keying (DQPSK).
What is the purpose of the distributed coordination function (DCF) in an Institute of Electrical and Electronics Engineers (IEEE) 802.11 wireless local area network (WLAN)?
It allows all clients on a WLAN to contend for access on the shared radio frequency (RF) transmission medium using the carrier sense multiple access with collision avoidance (CSMA/CA) protocol.
What is multipath?
Multipath is defined as the composition of a primary signal plus duplicate or echoed wavefronts caused by reflections of waves off objects between the transmitter and receiver.
What is downfade?
Downfade is an occurance when reflected waves, if out-of-phase with the main wave, cause decreased signal amplitude at the receiver.
When does nulling occur?
Nulling occurs when one or more reflected waves arrive at the receiver out-of-phase with the main wave with such amplitude that the main wave's amplitude is cancelled.
How is antenna diversity used to compensate for multipath?
Antenna diversity means using multiple antennas (outputs) and receivers (inputs) to compensate for the conditions that cause multipath.
Which of the following are methods for locating a hidden node and resolving the issue? Choose all that apply.
Use the RTS/CTS protocol to reduce the negative impact that hidden nodes have on the network.
Move the nodes so that they can all detect each other.
Increase power to the nodes.
Remove obstacles to the nodes.
When do collisions occur?
Collisions occur when two or more nodes sharing a communication medium simultaneously transmit data.
How do you troubleshoot for hidden node?
Troubleshooting for hidden node is performed by testing for degraded data throughput at all client locations.
What is near/far?
Near/far is a condition that occurs when an access point (AP) receives a distant client's signal at a lower power level than that of a nearer client.
What are troubleshooting methods for near/far?
Troubleshooting the near/far problem is taking a good look at a network layout, locations of stations on the wireless network, and transmission output power of each node.
What are solutions if three co-located APs don't provide enough bandwidth? Choose all that apply.
Use only two co-located APs operating on Channels 1 and 11....
Use 802.11-compliant equipment operating in the 5-GHz U-NII bands.
What is co-location?
Co-location is a common WLAN implementation technique used to provide more bandwidth and consequently, higher data throughput to wireless users in a given area.
You are building a three-access point, co-located, cross-vendor wireless network. What kind of behavior can you expect from this design?
Lower data throughput than if you used the same vendor's equipment.
What is the greatest reason for nonoverlapping channels to overlap?
The greatest cause for nonoverlapping channels to overlap is due to APs that are located too close together.
A spectrum analyzer is required to find this type of interference.
Typically, only disrupts a single carrier frequency.
A possible source is a microwave oven.
A highly directional antenna must be used to locate the interference source.
Any signal that interferes with the RF band from one end of the radio spectrum to the other and interference covers the entire range that is to be used, regardless of frequency.
What is used to identify narrowband interference?
Spectrum analyzers are used to locate and measure narrowband RF signals.
What can be used to protect an antenna from weather and from falling objects such as ice falling from a tree?
A radome protects an antenna from the elements may also protect an antenna from falling objects, such as ice falling from an overhead tree.
Why is it important to pay attention to adjacent channel interference when co-locating APs in an attempt to achieve higher throughput in a given area?
Co-located APs on non-overlapping channels can experience adjacent channel interference if there is not enough separation between the channels used.
What are the three conditions that affect the RF communications?
The three conditions that affect the RF communications are transmission power, antenna type, and environment.
What effect does the output power of a transmitting radio have on the range of the link?
A higher output power causes the signal to be transmitted a greater distance, resulting in a greater range.
How does the type of antenna used affect the range?
The type of antenna affects the range by either focusing the RF energy into a tighter beam, transmitting it farther (as a parabolic dish antenna does), or by transmitting it in all directions (as an omnidirectional antenna does), reducing the range of communication.
What causes the hidden node problem in a wireless local area network (WLAN)?
When a client (or node) can receive signals from an access point (AP), but an obstacle prevents the client from receiving signals from the other clients that are connected to the network.
How do you troubleshoot a hidden node?
Test for degraded data throughput at all client locations.
How might you confirm the presence of a hidden node on the network?
Turn on the request to send/clear to send (RTS/CTS) protocol and watch for increased network data throughput.
Which one of the following conditions occurs when an access point (AP) receives a distant client's signal at a lower power level than that of a nearer client?
Which one of the following tasks is the best choice for troubleshooting the near/far problem?
Review the location of the stations (clients) on the network.
You wish to build a wireless network that provides significantly better throughput than a single Institute of Electrical and Electronic Engineers (IEEE) 802.11b access point (AP). Which of the following is an acceptable solution?
Use IEEE 802.11-compliant equipment operating in the 5 GHz U-NII bands, allowing for more more non-overlapping channels.
What test instrument is used to locate and measure interfering narrowband radio frequency (RF) signals in an Institute of Electrical and Electronic Engineers (IEEE) 802.11 wireless local area network (WLAN), among other things?
A spectrum analyzer.
What causes co-channel interference in a wireless local area network (WLAN)?
An overlap in the signal ranges of access points (AP) or different WLANs operating on the same channels.
What are the three main conditions that influence the range of a wireless local area network (WLAN)?
Transmission power,,,, antenna type and location,,,,,, and environment.
What can be done to increase the coverage area of a wireless local area network (WLAN)?
Increase the transmission power, replace the omnidirectional antenna with a parabolic antenna, and use the 2.4 GHz radio band instead of the 5 GHz radio band.
Increase the transmission power, replace the omnidirectional antenna with a parabolic antenna, and use the 2.4 GHz radio band instead of the 5 GHz radio band.
A WEP key can be used to verify the identity of an authenticating station.
Most APs and clients can hold up to four WEP keys simultaneously.
The SSID of a WLAN station must match the SSID on the AP or of the other stations for the client to authenticate and associate to the service set.
The SSID is encrypted in every beacon that the AP (or set of stations) sends out.
Almost all APs have MAC filtering functionality.
Closed system describes a wireless system where APs can take the SSID out of the beacon frame.
Why is WEP not secure when used with shared key authentication?
WEP is not secure when used with shared key authentication because the AP transmits the challenge text in the clear and receives the same challenge text encrypted with the shared key. An intruder can quickly discover the secret key by comparing the two versions of the challenge text and can then use the key to decrypt all data traffic.
By implementing WEP in hardware, it is most likely that an AP can maintain data throughput with WEP enabled. What is a disadvantage of this type of implementation?
A disadvantage is the added cost of a more sophisticated AP.
How does filtering work?
Filtering works the same way as access lists on a router—by defining parameters to which stations must adhere to gain access to the network.
A per-packet __________key distribution with TKIP assigns a new WPA key to both the client and the AP for each packet sent between the two.
When the ____________server is built into the AP, the client must first associate with the access point.
______________upgrades WEP to fix the protocol's implementation of RC4.
____________is the customer-friendly term for the IEEE 802.11i security standard using AES.
What would be a good time to employ a WLAN gateway?
If a small business has significantly invested in APs and if the APs do not support scalable security measures, a business could employ a WLAN gateway rather than replace all of their APs.
When combined with Extensible Authentication Protocol (EAP), what can IEEE 802.1x provide?
IEEE 802.1x can provide a secure and flexible environment based on various authentication schemes in use today.
Even though dynamic keys add more overhead and reduce data throughput, what is an advantage of using them?
Dynamic keys make hacking the network through the wireless segment much more difficult.
Allows a network device with a UI to introduce IoT devices with no UI to the network.
Wi-Fi Easy Connect
Protects users, who are not using a password, from passive eavesdropping attacks.
Wi-Fi Certified Enhanced Open
Employs 192-bit encryption using cryptographic tools.
Protects users that have chosen insufficiently complex passwords, making brute-force dictionary attacks more time-consuming and difficult.
If WEP must be used, what steps should be taken to ensure that network data is adequately protected?
When using WEP, change WEP keys frequently, use MAC filters, and implement IEEE standard 802.1x and wireless VPN to ensure network data protection.
WPA2 operates in what two modes?
WPA2 operates in enterprise mode and personal mode, which is also known as PSK mode.
What is AES?
AES is a symmetric-key encryption standard that uses a single key to both encrypt and decrypt payloads.
Why do passive attacks, such as eavesdropping, leave no trace of a hacker's presence on or near the network?
Eavesdropping leaves no trace because the hacker does not have to connect to an AP to listen to packets traversing the wireless segment.
In an active attack, what can happen if a hacker progresses past a MAC filter?
In an active attack, the hacker can navigate to the APs and remove all MAC filters, making it easier to gain access next time.
What occurs when a hacker uses jamming to gain access to a network?
Jamming simply shuts down the WLAN by using an overwhelming RF signal.
What must the hacker have access to when perpetrating a man-in-the-middle attack?
In a man-in-the-middle attack, the hacker must first know the wireless clients' SSIDs, which are easily obtained, and also the network's security keys, if the wireless connection is not wide open and without security.
What are some best practices to follow for information and physical security? Choose all that apply.
Company personnel are encouraged to continuously be on the lookout for noncompany personnel lurking around the company buildings, which can also be effective in reducing on-premises attacks.
Wireless security keys should only be known by network administrators.
True or False? A network user can easily circumvent WLAN security by connecting to the Internet over the wireless network.
What types of software should you install on your mobile users' laptop computers to protect them from malicious attacks while operating on public wireless networks? Choose all that apply.
Security keys are an effective solution for reducing the risk of casual eavesdropping.
APs should emit strong signals that extend into the organization's parking lot or beyond.
User authentication should be based on device-independent schemes such as usernames and passwords, biometrics, smart cards, token-based systems, or some other type of secure means of identifying the user, not the hardware or organization.
Always connect APs to hubs instead of switches.
How might a network administrator ensure that security audits and inventories are not overlooked?
By documenting audit procedures in the security policy, an network administrator can ensure that security audits and inventories are not overlooked.
Why is it important that the network administrator implement user-based authentication as soon as possible upon installing a WLAN infrastructure?
It is important that the network administrator implement user-based authentication as soon as possible upon installing a WLAN infrastructure because user authentication is a WLAN's weakest link and the IEEE 802.11 standard does not specify any method of user authentication.
What's the best way to discover rogue APs?
To discover rogue APs, regular AP discovery sessions should be scheduled but not announced.
When are WDMZs generally implemented?
WDMZs are generally implemented in medium- and large-scale WLAN deployments.
What initialization vector (IV) do most weak implementations of the Wireless Equivalency Protocol (WEP) use?
How can filtering augment some of the security limitations of Wired Equivalent Privacy (WEP) in a wireless local area network (WLAN)?
By defining parameters to which client stations must adhere in order to gain access to the network.
Which term describes a wireless system in which the access point (AP) removes the wireless local area network's (WLAN) service set identifier (SSID) from the beacon frames?
What basis does a wireless local area networks (WLAN) use an Institute of Electrical and Electronics Engineers (IEEE) 802.1x protocol to control network access?
Access points (AP) must support what encryption techniques in order to comply with Institute of Electrical and Electronics Engineers (IEEE) 802.11i security standards?
Temporal Key Integrity Protocol (TKIP), Advanced Encryption Standard (AES), and AES-CCMP (Counter-Mode/CBC-MAC Protocol).
What is a man-in-the-middle attack on a wireless local area network (WLAN)?
A situation in which a hacker uses an access point (AP) to effectively hijack mobile nodes (clients) by sending a stronger signal than the legitimate AP is sending.
What type of wireless local area network (WLAN) attack could cost an employee their job because network usage logs point directly to the employee whenever a hacker gains access to the employee's domain login information and causes havoc on the network?
A passive attack.
How might a wireless local area network (WLAN) administrator ensure compliance with security audits?
Document audit procedures in the security policy.
For maximum security, you should base your wireless local area network (WLAN) user authentication on which one of the following?
Device-independent schemes, such as user names and passwords.
To prevent hacker access to passwords and Internet protocol (IP) addresses, why would you want to place wireless access points (AP) on switches instead of hubs?
Switches prevent the broadcast of packets to all network segments.
What is the purpose of performing a site survey for a WLAN?
In a WLAN, performing a site survey ensures that mobile workers experience continually strong RF signal strength as they move around their facility.
What knowledge can be obtained by performing a site survey?
By performing a site survey, a broadband technician obtains knowledge of their clients' needs, determines the sources of interference, locates the "dead" spots (where no RF coverage exists), and finds the best locations in which to install the APs.
Your customer wants a wireless link connecting their two warehouses located 2.5 miles from the local airport. They want to mount the antennas on a tower to raise them above several tall trees and other obstacles. As part of your site survey, who will you need to notify if the tower is 200 feet or more above ground level?
Your site survey preparation interviews indicate that the customer's users will roam within the building. Which of the following situations should you consider as part of the site survey? Choose all that apply.
What is one of the primary differences between performing a site survey for a hospital and for a real estate office?
When performing a site survey for a hospital, security planning is crucial, whereas, for a real estate office, although security is important, it is not mandated by law, so rudimentary security measures might suffice.
What is one of the first items to request from a network manager when preparing for a site survey?
Blueprints or a map showing the layout of the facility is one of the first items to request.
Why should Wired Equivalent Privacy (WEP) not be the only WLAN security method used?
Because WEP can be easily circumvented, it should not be the only method of security.
A spectrum analyzer is used to find sources of RF interference.
It only takes one antenna to create a wireless link depending on the number of locations involved in the connection.
A variable power AP radio simplifies the site survey process by eliminating the need to carry multiple gain antennas.
Part of a spectrum analysis should be to locate any IEEE 802.11 networks around the implementation area of the proposed WLAN.
A digital camera may be used when performing a site survey to obtain screen snapshots of RF signal levels.
Why is it important for the AP used during a site survey to have variable output power?
It is important because the variable output power feature allows for easy sizing of coverage cells during the site survey.
To perform a quality site survey, what quantitative measurements should be recorded?
To perform a quality site survey, signal strength measured in dBm, noise floor measured in dBm, SNR measured in dB, and link speed should be recorded.
When checking for signal strength and coverage areas while roaming around the facility, why is using cell phones or tablets preferred?
It is preferred that cell phones or tablets are used instead of laptops to perform the site survey because of their longer battery life and easier portability.
For __________ surveys, record link distance on a copy of a diagram or sketch of the property.
For__________locate and record the locations of potential RF sources, such as microwave ovens, elevator motors, baby monitors, cordless phones, on a copy of the facility blueprints or a drawing of the facility.
For __________ surveys, locate and record the locations of potential RF sources, such as microwave ovens, elevator motors, baby monitors, cordless phones, on a copy of the facility blueprints or a drawing of the facility.
Start by placing an AP in what seems to be a logical location. Starting in the center of an area is practical when using ________________antennas. In contrast, when using _____________ antennas, consider starting at one end of a stretch of intended coverage area.
When taking measurements, have a laptop or tablet running the site survey utility software and pick a starting point in the room. As you slowly walk around the room, what data should be recorded for each area?
While walking around the room, the following measurements should be taken: data rate (measured Mbps), signal strength (measured in dBm), noise floor (measured in dBm), and SNR (measured in dB).
How are data rate boundaries taken in a WLAN?
Data rate boundaries are taken in concentric zones around the AP. For example, in an IEEE 802.11b WLAN, the data rates are recorded where the rate decreases from 11 Mbps to 5.5 Mbps to 2 Mbps to 1 Mbps.
When identifying interference sources, the surveyor asks questions about potential sources of narrowband and spread spectrum RF interference. What is the first question asked?
The first question when identifying interference sources is "Are there any existing WLANs in use in or near the facility?" Existing WLANs can cause hardship on a site surveyor if permission is not provided to disable existing radios as needed.
When looking for objstacle-induced signal loss, find and record all sources of interference while mapping the range and coverage patterns. When measuring the coverage in a break room, why should you take measurements both while the microwave oven is operating and when it is off?
You should take measurements for both states because, in some cases, the microwave oven could impact the entire WLAN infrastructure if the microwave is an older model.
If the distance between the AP and the network connection is more than 100 meters, what can be done?
For distances of more than 100 meters between the AP and the network connection, shielded twisted-pair cabling or an AP that supports a fiber-optic cable connection can be used.
Which of the following is true regarding site survey reporting? Choose all that apply.
Manageable device names and AP channel settings should be included in the wireless site survey.
Save every piece of data collected and include everything with the report as an attachment, appendix, or another set of documentation.
Why should all the data collected as part of a site survey for a WLAN be included in the survey report as an attachment, appendix, or separate set of documentation?
All collected data should be part of the site survey because it could be needed in the future.
What are some data throughput facts that should be detailed in the site survey?
Using the drawings made on blueprint copies, include in the site survey the details of bandwidth and data throughput findings showing exactly where in the facility the greatest and the least of each will occur. Be sure to include screenshots of the actual numeric measurements that were recorded.
What are some RF interference and obstruction findings that should be included in the site survey?
Findings should explain how the RF interference sources will affect the WLAN once it is installed and include suggestions for removing these sources where possible.
What is the most basic question you should ask a customer before visiting the customer's facility to perform a site survey?
The anticipated number of users, security requirements, data throughput requirements, and budget.
What information should be gathered during the wireless local area network (WLAN) site survey in a convention center for an upcoming trade show?
Identify who will be installing access points (AP) in ceilings that could be 40 feet high.
What test should be performed during the site survey to enable the design engineer to understand and control what the user's experience will be on the wireless local area network (WLAN)?
A data throughput test.
Why is it suggested that all data collected as part of a site survey for a wireless local area network (WLAN) be included in the survey report as an attachment, appendix, or separate set of documentation?
The data could be needed in the future.
What are some of the access points (AP) facts that should be detailed in a wireless local area network (WLAN) site survey?
Location within facility, antenna type to be used, power output settings, how power will be provided to unit, and the expected data throughput per unit
Ideally, what should the next step be after you complete the wireless local area network (WLAN) site survey and provide the survey results in a report to the customer?
A wireless consulting firm should be given the site survey report so that it will then be able to provide effective information on equipment purchasing and security solutions.
What should you note in the wireless local area network (WLAN) site survey if a semidirectional antenna is required for adequate coverage?
The antenna orientation along with the antenna's side and back lobes for coverage and security reasons.
What are some desired features of an access point (AP) used to perform wireless local area network (WLAN) site surveys?
Variable output power and external antenna connectors.
How would you use a laptop computer, tablet, or cell phone when performing a site survey for a wireless local area network (WLAN)?
By checking for signal strength and coverage areas while roaming around the facility.
What are some requirements of a wireless local area network (WLAN) in a hospital that make it an effective training ground for individuals who want to immerse themselves in WLAN technology?
Roaming across large distances, a limited number of users on an access point (AP) due to mandated security, and medical applications that are often connection-oriented between the client and server.
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