NCTI 2020 Progression: Field Tech II - III Conventional Exam | Q & A (Complete Solutions)

NCTI 2020 Progression: Field Tech II - III Conventional Exam | Q & A (Complete Solutions) What is one reason why broadband cable operators install fiber-optic cable in stages instead of changing the infrastructure all ...

NCTI 2020 Progression: Field Tech II - III Conventional Exam | Q & A (Complete Solutions) 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)? Optical splitters. 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? Distributed star. 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. 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 = ? E/R The square of 7 = 49 The square root of 81 = 9 0.00004 = ______ x 10 to the power of ______. 4, -5 (75 x 10 to the power of 3) + (25 x 10 to the power of 4) = 32.5 x 10 to the power of 4 10 to the power of -3 has a metric prefix of ______. Milli (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) = (*Wrong) 100 × 10^3 (-25) + (42) + (-62) + (20) = -25 (17) x (-19) = -323 (-17) - (-34) = 17 -49/-7 = 7 (20) / (-4) + (-2) x (-10) - (-2) x (7) = 29 3 6/9 + 6 1/3 + 9 5/9 = 19 5/9 4/7 x 9 4/11 = 5 27/77 7 3/8 divided by 7 1/4 = 1 1/58 8.13 X 0.123 = 0.99999 0.5349 divided by 0.1420 = 3.7669014 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? Deductive. 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. 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? Diagnosing symptoms. 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. 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? 76 Mbps. 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. 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? Ground fault. 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 is it called when several computers are sharing files without a WAP? ad-hoc mode. What is the standard encryption method used with WPA2? AES. 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? Infrastructure. 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? WPA2. How many channels are available with IEEE 802.11g? 11 What is the last step of the basic wireless access point (WAP) setup? Apply security. 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? 802.11g 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 IEEE 802.11 wireless local area network (WLAN) standards specifies both spread spectrum RF and infrared (IR) transmission technologies? 802.11 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 wireless standards utilizes the 5 gigahertz (GHz) frequency band for its signal transmissions? 802.11n Why are wireless local area networks (WLAN) usually deployed in an access capacity instead of as the network's core layer? WLANs 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 (LAN) operate? The Data Link Layer. What type of connectivity is needed to connect networks between two buildings located across the street from each other? Point-to-point (P2P). 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 (AP), rooftop access, lightning, trees, mountains, tower access, and other physical obstacles to connectivity. 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"? Refraction. Which of the voltage standing wave ratios (VSWR) shown below is best for transferring radio frequency (RF) energy between connections? 1.2:1 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? RF 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 power actually radiated by the antenna element. What unit of measurement is used to express the gain of an antenna? Decibels isotropic (dBi). 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 milliwatts (mW)? * (WRONG)100 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? 75 mW 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? Processing gain. 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 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.