Fiber Install and Activation Exam 2023 Graded A+

Which standards organization is considered to be the creator of the worlds' most recognized communications standards, known as "recommendations"? - ANSWER-The International Telecommunications Union (ITU) In which component in a fiber-optics communication system do changes to the intensity of the optical signal occur? - ANSWER-The optical transmitter What is a drawback of using Fabry-Perot (F-P)lasers in high-speed data (HSD) networks? - ANSWER-The emission of a number of discrete wavelengths or side modes. Why are laser diodes most effective when coupled to singlemode fiber? - ANSWER-Its high coupled power, directionality, and speed. What are the factors that contribute to an optical receiver's sensitivity? - ANSWER-Noise, responsivity, response time, linear response, back reflection, optical detector. What is a positive-intrinsic-negative (PIN) diode? - ANSWER-An optical detector with current flow that is linear to the intensity of light photons, with one electron/hole pair created for every absorbed photon until saturation. What does the amplification process in an avalanche photodiode (APD) introduce into the electrical output of an optical detector? - ANSWER-Noise What function does the detector in an optical receiver perform? - ANSWER-Conversion of an optical carrier to an electrical signal, and demodulation of the modulated optical carrier. What happens if the optical signal exceeds the maximum specified input power into a photodetector? - ANSWER-Nonlinear operation resulting in distortion, data errors, and signal loss. What is a characteristic of light in a laser beam? - ANSWER-The laser beam consists of a limited range of wavelengths (monochromatic), with all light waves in phase (coherent light). Monitoring the status of optical nodes - ANSWER-Involves the use of a node transponder that continuously monitors a number of critical functions. Digital return path transmissions - ANSWER-Use dense wavelength division multiplexing (DWDM) digital return transmitters in hub-to-headend architectures. What is channel bonding? - ANSWER-A 3.0 revision to DOCSIS that significantly increases upstream and downstream transport data rates. What is MPEG? - ANSWER-A universally accepted standard for digital television, first released in 1992. Which of the following is true about optical nodes? - ANSWER-They contain four main sections: the optical receiver, the RF amplifier module, the reverse optical transmitter, and the DC power supply. Internet protocol telephony systems in broadband cable networks - ANSWER-Require a call management server, media gateway, signaling gateway, billing system, and CMTS. In a centralized server video-on-demand architecture - ANSWER-The number of servers needed for video content storage is smaller than in the distributed server architecture. Which of the following statements about local ad insertion is true? - ANSWER-Local ad insertion is performed usually by a video server. In regard to providing high-speed data service, - ANSWER-The CMTS can provide a data transfer rate up to 38 Mbps, using 256-QAM in a single 6Mhz channel. Which of the following is true about the SONET transmission standard? - ANSWER-SONET is the North American standard used for telephony applications. Why was the zero-dispersion point in single-mode fiber moved to 1,550 nm? - ANSWER-To take advantage of the low intrinsic absorption and lower attenuation at 1550 nm in single-mode fiber What type of single-mode fiber is intended for fiber-to-the-home installations? - ANSWER-The ITU-T G.657 bend-insensitive fiber (BIF) What are the primary causes of intrinsic loss in single-mode fiber? - ANSWER-Material absorption and Rayleigh scattering. The phenomenon, total internal reflection, is what enables an optical fiber to guide light. What characteristic of optical fiber causes total internal reflection? - ANSWER-The difference in refractive indexes, between cladding and core, causes light to be reflected off the cladding and back into the core along the optical fiber. Where would you expect Fresnel reflections to occur in a fiber-optic network? - ANSWER-At connections and mechanical splices where the signal source is entering or exiting the cable. Chromatic dispersion is a combination of which two dispersions? - ANSWER-Material and waveguide dispersion. What is one advantage and one disadvantage of single-mode fiber with a large mode field diameter? - ANSWER-The larger the MFD, the easier it is to splice and connectrorize the fiber, although it becomes more sensitive to bending losses. What is the current standardized outside diameter of the cladding of single-mode fiber? - ANSWER-It is 125 µm, with an accuracy of ±1 µm. What do diameter differences between spliced fibers look line on an optical time domain reflectometer? - ANSWER-Gain in one direction and high loss in the opposite direction. Besides protection, what else must the coating on an optical fiber do? - ANSWER-Function over a wide temperature range' be compatible with cable gels adhere to the glass cladding over the lifetime of the cable; and be mechanically strippable for splicing operations. How do technicians know the specific type of single-mode fiber used in a particular project? - ANSWER-They have read the project's specification records. Which type of fiber-optic cable provides the most stable transport characteristics and additional protection from stresses caused by macrobends and microbends? - ANSWER-Loose-tube cable What is a consideration for the use of ribbon fiber? - ANSWER-Ribbon fiber requires different tools and equipment to perform splicing. What are the two critical elements that align the optical fibers in a connection? - ANSWER-The ferrules and the mating adapter. In an optical network, what is reflectance? - ANSWER-Reflectance is the reflected light from a single Fresnel refection event How should surface particulates usually be removed from optical connectors? - ANSWER-By using a compressed-air cleaner designed for optical connectors. Since they provide the same functions, what is the primary difference between the fiber distribution hub (FDH)and fiber access terminal? (FAT) - ANSWER-The FAT is typically easier to install and has a lower fiber counts than the FDH. Which statement about pigtails used for optical fiber terminations is true? - ANSWER-Prior to splicing, pigtails should be labeled to correspond with the correct color code and patch panel designation. How are optical splitters used in the forward path? - ANSWER-In the forward path, optical splitters are used as passive combining devices that stream an optical signal across two common fibers. Which optical splitter package is similar in appearance and size to a standard fusion splice protector? - ANSWER-Fused bi-conical taper (FBT) In what applications is a splice closure used? - ANSWER-Splice closures are used to protect optical fibers and splices against a full range of environmental changes in aerial installations or below ground in vaults. When preparing a fiber-optic cable for splicing, what is the purpose of removing approximately 2.5 cm of jacket and any armor that is present, for the end of the cable? - ANSWER-To access the cable's rip cord and to check the cutting depth of the knife or ringing tool. What does water do to the glass core of an optical fiber? - ANSWER-Water causes the glass core of the optical fiber to become opaque, which degrades the signal as it's transported through the fiber. Whe preparing a splice closure, what should be done with the fiberglass rod strength member that runs down the center of loose-tube fiber-optic cable? - ANSWER-Trim the strength member back for convenience, but leave it long enough to be tightly clamped to a strain-relief lug in the closure. What is the purpose of splice trays inside splice closures? - ANSWER-Splice trays are designed to provide protection for mechanical splices, fusion splice protectors, and optical splitters as well as provide storage for the required fiber slack. How should the buffer tubes be secured in the closure? - ANSWER-The buffer tubes should be secured with tie wraps to allow slight movement without pulling or stressing the optical fibers. How are optical splices secured in a splice tray? - ANSWER-Retaining clips hold optical splices in place in a splice tray. What is the purpose of buffer tubes in fiber-optic cable? - ANSWER-Buffer tubes protect and separate the optical fiber in smaller bundles. When splicing fiber-optic cable, why is it a good safety practice to clean off fiber strippers and other hand tools after each use? - ANSWER-To prevent the accidental transfer of the fiber debris to fiber chips onto clean hands. Where would you expect to install a mid-entry splice in a fiber-optic cable network? - ANSWER-A location where select number of optical fibers need to be spliced, and the remaining buffer tubes and fibers remain untouched. Which type of fusion splicer is ideal for fiber-to-the-x splicing? - ANSWER-The fixed V-groove splicer. What are some prerequisites before performing a fusion splice of optical fibers? - ANSWER-A controlled environment such as a splicing van, trailer, or tent and a stable work surface that is large enough to accommodate the fusion splicer, tools , and the splice closure. When would a mid-entry splice in a fiber-optic network be used? - ANSWER-In a self-healing ring network that requires only two fibers to feed an optical fiber drop. What is required of mechanical splices used for acceptance testing? - ANSWER-A mechanical splice used for acceptance testing should be simple to use and reusable. Why are Velcro straps preferred over standard plastic tie wraps when bundling pigtails for storage in a splice panel? - ANSWER-Because Velcro straps are removable and can hold the pigtails together without placing undue strain on the optical fibers. When preparing fiber-optic cable for connection to a patch panel, how much buffer tube and fiber slack should be provided? - ANSWER-Leave enough slack in the buffer tubes to allow the splice trays to reach the splicing equipment and enough fiber slack to store on individual trays for later additions, moves, and changes. If tight-buffered distribution fiber-optic cable is installed between the master splice panel in an optical entrance enclosure (OEE) and a rack-mounted fiber optic distribution panel, where in the facility must the distribution panel be located? - ANSWER-The distribution panel can be located anywhere in the facility since the distribution cable complies with indoor code requirements for riser or plenum installations. The quality and attenuation value of a mechanical splice of optical fibers is dependent on which tool during the preparation process? - ANSWER-The quality and attenuation value of the mechanical splice of optical fibers is dependent on the quality of the cleaving tool. What step should be performed at the beginning of every fusion splicing operation? - ANSWER-Make a number of test splices to set up the fusion splicer and to verify the instruments's setting and calibration for both the environment and the type of fiber to be spliced. Which fusion splicer alignment method uses a camera to align the optical fibers before splicing? - ANSWER-The profile alignment system (PAS) method. The National Electrical Safety Code (NESC) provides guidelines concerning which portion of the fiber-optic cable network? - ANSWER-Minimum