發信人: wishforyou@kkcity.com.tw () 日期: 11 Jun 2003 13:59:03 GMT 標題: [急徵]Cisco TCPIP 第八九章 的答案~~~ 信群: tw.bbs.comp.www 看板: TWBBS/www/A0VEEDD7 來源: <46cUed$LGs@bbs.kkcity.com.tw>:94392, bbs.kkcity.com.tw 組織: KKCITY [急徵]Cisco TCPIP 第八九章 的答案~~~ 目前只有題目....沒有答案~~~ 明天要考試(同樣的題目)...所以拜託各位大哥大姐...幫一下忙~~ 給我正確答案.... 請回我信箱...謝謝 ^^ ------------------------------------------------------ 1 All the items below are personal safety precautions before you install cable except: Wear long sleeves. Wear long pants. Wear baggy clothes. Check for power cables. 2 What should be done when preparing to run cable? Cut the cable before pulling it. Unroll it before pulling it through the ceiling. Label the boxes and cable. Take the cable out of the boxes. 3 Why shouldn't you install a jack in the bottom five centimeters of a wooden baseboard? The bottom plate of the wall will prevent you from pushing the box into the baseboard. Most floors have metal supports that produce electromagnetic interference when close to the jack. Dust and dirt accumulate under it that can then get into the connection and affect network performance. It's so close to the floor, there isn't enough space for most people to work and manipulate the wires. 4 When running cable from the wiring closet to wall jacks, where is the cable itself labeled? at each tie at each end at the jack end at the panel end 5 What kind of jack must be used for making a connection to a Category 5 unshielded twisted pair cable in a horizontal cabling scheme? RJ-45 BNC UTP 55 EIA 45 6 What kind of a cable must you use when laying cable through spaces where air is circulated? shielded double coated fire rated unshielded 7 What is one advantage of using distribution racks for mounting patch panels? allows easy access to both the front and back of the equipment provides neutral ground inexpensive compared to brackets requires minimal wall space 8 What is the most important thing to do before you work in walls, ceilings or attics? Label the faceplate. Measure out the cable. Turn off power to the area. Install the patch panel. 9 Why is the wiring sequence critical when RJ-45 jacks are used at the telecommunications outlet in a horizontal cabling scheme? For the network to function properly. Improper wiring sequence will short out the connection. You could get a nasty electrical shock. The collision rate is adversely affected. 10 What type of raceway should be used if it will be visible in the room? channel guide decorative ladder rack gutter 11 When should cable not be routed in an existing raceway? if the raceway distance exceeds 100 feet if the raceway material is partially metallic if it already contains a power cable if it contains a telephone line 12 What is the central junction for the network cable? POP server center point wiring closet 13 If you have one wiring closet and you want to add more, what name is given to additional wiring closets? IDFs MDFs Extended Stars POPs 14 What should be used to mount cable to a wall? tie wraps electrical tape staples paperclips 15 Which of the following is a source that can produce interference on UTP cable? fluorescent lights fiber-optic cabling bridges coaxial cabling 16 Which best describes a patch panel's function? It serves as a temporary fix to network problems. It acts as a router for temporary networks connecting the various devices often found at conventions and shows. It acts as a switchboard where horizontal cabling from workstations can be connected to other devices to form a LAN. It allows the network administrator to test the entire network cabling from a single location. 17 How many pins are on each of the ports of a patch panel? 4 pins 8 pins 11 pins 45 pins 18 What is the first thing you should do if near-end crosstalk is detected? Redo all connections at the patch panel. Isolate which connection is the cause by running a TDR test. Redo all connections at the cross connects. Visually check the horizontal cabling. 19 How is an RJ-45 jack surface mounted? with a punch tool with Velcro flush with the surface adhesive backed or screw box 20 Why are split pairs a problem for network installations? The wires are unshielded and easily lose synchronicity. The wires are part of different circuits so signals are not protected and cross-talk occurs. The wires are part of different circuits and easily shorted out by power spikes. It is difficult to detect split pairs which requires performing a wire map. 21 What is a rough diagram that shows where the cable runs are located called? cut sheet sketch cable plan cabling route 22 What tool would you use to attach CAT5 cable to a patch panel? 110 patch tool cable terminator punch tool patch terminator 23 Why is establishing a baseline performance level for a network important? for fulfilling one of the requirements necessary for you to get your network certification for providing your client with proof of a successful installation for future periodic testing of the network and diagnostics for obtaining a network registration and identification number from TIA/EIA and IEEE 24 Which of the following describes a cable tester measurement of signal attenuation? It measures the reduction in power of a signal received from a signal injector. It measures the increase in power of a signal received from a signal injector. The signal injector attaches to the near end of the cable. The frequency to be used for testing is specified in EIA/TIA 568A. 25 How does a cable tester (a TDR) measure distance? The cable tester identifies signal degradation, indicating the cable is longer than the acceptable maximum length. It determines the time a signal takes to be reflected back from closed-ended cable. It times the signal sent towards and reflected back from the end of an open-ended cable. It measures the ability of other devices on the network to receive and send signals through the cable. -------------------------------- 1 What is a possible problem associated with multiple building grounds? They are often at the same potential with respect to each other They do not allow electrical current to flow between the buildings Separate protective devices are needed at each building They may present a shock hazard due to different potentials 2 What is another term that can be used to describe an Intermediate Distribution Frame (IDF)? work area (WA) telecommunications outlet (TO) main cross-connect (MCC) horizontal cross-connect (HCC) 3 What is the purpose of providing a ground, or earth, connection on a wall power outlet? To reduce the resistance in the electrical circuit To link the neutral wire to ground To allow fault currents to flow to ground To complete the circuit for normal current to flow 4 An electrician has investigated your recent power problems and has suggested that they are caused by oscillation. What is the BEST solution to your problem? Move the network server to another room Replace UTP with fiber optic cable Rewire the electrical system Fit commercial surge suppressors 5 What is the ideal room temperature and relative humidity at which a wiring closet should be maintained? 21 degrees Celsius / 45 % relative humidity 21 degrees Fahrenheit / 45 % relative humidity 45 degrees Celsius / 21 % relative humidity 45 degrees Fahrenheit / 21 % relative humidity 6 In a controlled electrical circuit, which path do electrons normally follow? From the positively charged source to ground From the negatively charged source to a positively charged source From the more positively charged source to the less positively charged source From the negatively charged source to ground 7 Why is copper considered a good conductor of electricity? It offers a path of least resistance to current flow It is easily formed into wires It is cheaper than other metals It reduces power line noise 8 Why is fiber optic cable commonly used as a network backbone between campus buildings? It provides a less resistive path for electrical current to flow from one building to another It enhances the signals at the physical layer It reduces the hazardous effects of electrical potential difference and lightning strikes It is cheaper and easier to install than copper wire 9 What is an alternative name for backbone cabling? Horizontal cabling Vertical cabling Main cabling Trunk cabling 10 Why are exposed metal components normally connected to the ground, or earth, pin of a power outlet? The connection is needed to increase the resistance of the circuit to ground If an electrical fault occurs in the equipment, the connection will reduce the chance of shock Connecting the metal to ground makes it act like an insulator The ground connection can act as an alternative path for controlled current flow if the neutral wire is disconnected 11 Which of the following environmental specifications are recommended for a wiring closet ? Carpeted floor; tiled walls and an inward opening door Wooden floor; brick walls and fluorescent lighting Tiled floor; internal power outlets and a dropped ceiling Raised floor; wood covered walls and an internal light switch 12 What features should be considered when assessing a potential wiring closet? It should be secure and situated on the first (ground) floor It should be secure and close to the POP It should be within 150 m of the MDF and close to an entrance It should be an internal room and close to the electrical supply distribution 13 What is the term used to describe a problem in an electrical system between the hot, or live, wire and the neutral wire? An isolated mode problem A ground fault problem A common mode problem A normal mode problem 14 What is one of the most significant causes of oscillatory noise problems on a power circuit? Long wiring runs School photocopiers Locating power cables in elevator shafts Air conditioners cycling on and off 15 Where does the horizontal cable extend? From the main distribution frame in the wiring closet to the vertical cross connect in the intermediate distribution frame From the telecommunications outlet in the work area to the horizontal cross-connect in the telecommunications closet From the patch panel in the point of presence to the backbone connection in the customer premises equipment From the telecommunications outlet in the wiring closet to the conduit in the intermediate distribution frame 16 What function does an electrical insulator perform? It completes the circuit, allowing current to flow It reduces the resistance in an electrical circuit It allows a short circuit to be present It prevents uncontrolled current flow 17 What causes Electrostatic Discharge (ESD)? Long power lines Faulty electrical equipment An accumulation of static electricity An increase in atmospheric humidity 18 Which statement BEST describes the current flow in an electrical circuit with a DC source? It is constant over time It varies over time It increases with time It decreases with time 19 What is the maximum length specified for 62.5/125μm multimode optical fiber run between the MDF and IDF? 90 m 800 m 2000 m 3000 m 20 What device is best used to minimize the effects of power line sags and brownouts? A primary protection device A surge suppressor An optical isolator An uninterruptible power supply 21 Why can digital electronic equipment, such as a computer, malfunction if subjected to excessive power line noise? Logic gates are unable to correctly distinguish the noise polarity The noise enhances the digital signal edges The noise replaces the digital signal Logic gates are unable to correctly distinguish between a one and a zero 22 What are the three components that make up an uninterruptible power supply? A battery, inverter and battery charger A MOV, capacitor and diode A generator, changeover circuit and server software A circuit breaker, fuse and battery 23 Which of the following problems is caused by too high a humidity level in a wiring closet? Signal degradation Copper wire corrosion Insulation failure Power surges 24 A potential wiring closet has been identified in a building with a floor area of 930 sq. m. The distance from this closet to the furthest workstation is 127 m. How many ADDITIONAL wiring closets would need to be installed? 0 1 2 8 -- ┌─────◆ＫＫＣＩＴＹ◆─────┐  ╱  ╱  ￣ ▌￣ ￣ ╲╱ ＢＢＳ 城邦 │ bbs.kkcity.com.tw │  ╲  ╲  ╴ ▌ ▌ ▏ ＫＫ免費撥接 └──《From:163.25.118.43 》──┘ 電話:40586000 帳號:kkcity 密碼:kkcity  .