CCNA 1. Networking Basics v3.1.1 Student Lab Manual (796248), страница 7
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All resistancesshould be less than one Ohm (Ω), except the light bulbs. All the devices except the battery shouldregister continuity with the tone, indicating a short circuit or a conducting path.Check the following resistances. Turn the meter off when finished or it will drain the battery.Item to Measure theResistance ofSet Selector andRange Scale toResistance ReadingPieces of wire to connectcomponentsLight switchLight bulbsStep 2Measure the voltage of the battery with nothing attached to it, unloaded.Item to Measure the Voltage ofSet Selector and RangeScale toVoltage Reading6 V Lantern battery with no loadStep 3 Build a series circuitBuild a series circuit one device at a time.
Use one battery, one switch, one bulb, and connectingwires.Connect the battery positive lead to the end of one wire. Connect the negative lead to theother wire. If the switch is turned on, the bulb should light.Disconnect one device and see that the circuit is broken. Did the bulb go out?_______________________Step 4 Measure the battery voltageMeasure the voltage across the light bulb while the circuit is running.The switch should be turned on and the light bulb should be lit.What was the voltage across the light bulb with the light bulb on? _______________________Step 5 Add the second bulbAdd a second bulb in series and measure the voltage across the light bulb again.What was the voltage across the light bulb with the light bulb on? _______________________2-3CCNA 1: Networking Basics v 3.1 - Lab 3.1.5Copyright 2003, Cisco Systems, Inc.ReflectionHow do series circuits apply to networking?______________________________________________________________________________________________________________________________________________________________________________________________________________________________3-3CCNA 1: Networking Basics v 3.1 - Lab 3.1.5Copyright 2003, Cisco Systems, Inc.Lab 3.1.9a Communications CircuitsObjective•Design a simple communication system that is fast and reliable.•Build the system using common materials.•Test the system.Background / PreparationFor reliable communications to take place on a network, things like the physical method of signalingand the meaning of each signal or series of signals must be defined ahead of time.
Create a simplephysical network and agree on some basic rules for communication in order to send and receivedata. This will be a digital network based on the American Standard Code for InformationInterchange (ASCII). It will be similar to the old telegraph Morse code-based systems.
In these oldersystems the only means of communicating over long distances was by sending a series of dots anddashes as electrical signals over wires between locations. Although the technology used will be moresimple than real systems, many of the key concepts of data communications between computers willarise. This lab will also help to clarify the functions of the layers of the OSI model.Each team must design, build, and test a communications circuit with another team.
The goals are tocommunicate as much data, as quickly and with as few errors, as possible During thiscommunication, spoken, written, or nonverbal communication of any kind, is not allowed. The onlycommunication allowed is over the wire. The teams must agree on the physical connections and onthe coding to use. One team will send a message to the other team. The other team must interpretthe intended message without knowing ahead of time what the message was. Keep the OSI model inmind as the system is designed.Prior to starting the lab, the teacher or lab assistant should have one multimeter availablefor each team of students and various items for construction of a simple communication network.Work in teams of two to four.The following resources will be required.
Review the purpose of each of the following required itemsbecause it will help in the design of the network.Network Construction ItemRequiredPurposeFluke 110, 12B or equivalentmultimeterFor testing communication connections20' Category 5 UTP cableFor the physical communications lines. The cabling medium.ASCII chartTo help with coding and interpretation of signals.
If there is nohardcopy of the 7-bit ASCII code chart, search the Internet for thewords “ACSII chart”.Light switchTo activate the signaling device in order to create the digital on/off,binary, signals1-2CCNA 1: Networking Basics v 3.1 - Lab 3.1.9aCopyright 2003, Cisco Systems, Inc.6v light bulbs with bulb bases or LEDswith resistorsTo act as the signaling device6v lantern batteryTo power the signaling deviceWire cutters or wire strippersTo adjust the length and prepare the ends of the communication linesLayer 1 issuesConnect two pairs of wire in order to have communication in both directions, half or full duplex.Layer 2 issuesCommunicate a frame start and stop sequence. This is a sequence of bits that is different than thecharacter and the number bits transmitted.Layer 3 issuesInvent an addressing scheme for hosts and networks, if it is more than point-to-point communication.Layer 4 issuesInclude some form of control to regulate quality of service.
For example, error correction,acknowledgment, windowing, or flow controls.Layer 5 issuesImplement a way of synchronizing or pausing long conversations.Layer 6 issuesUse a means of data representation. For example, ASCII encoded as optical bits.Layer 7 issuesBe able to communicate an idea supplied by the instructor or invent a message.Reflection1.
What issues arose as the communications system was being built, that apply to datacommunications between computers?_____________________________________________________________________________________________________________________________________________________________________________________________________________________2. Analyze the communications system in terms of the OSI layers._____________________________________________________________________________________________________________________________________________________________________________________________________________________2-2CCNA 1: Networking Basics v 3.1 - Lab 3.1.9aCopyright 2003, Cisco Systems, Inc.Lab 3.1.9b Fluke 620 Basic Cable TestingObjective•Use a simple cable tester to verify whether a straight-through or crossover cable is good or bad.•Use the Fluke 620 advanced cable tester to test cables for length and connectivity.BackgroundWork with several cables that have already been made.
Test them for basic continuity, breaks inwires, shorts, two or more wires touching, using a basic cable tester. In future labs similar cables willbe created.Simple Cable Testers: There are a number of basic cable testers available for less than U.S. $100.They usually consist of one or two small boxes with RJ-45 jacks.
Plug the cables to be tested the RJ45 jacks. Many models are designed to test only Ethernet UTP cable.Both ends of the cable are plugged in to the proper jacks. The tester will test all eight wires andindicate whether the cable is good or bad. Simple testers may have only a single light to indicate thecable is good or bad. Other testers may have eight lights to indicate which wire is bad. The testershave internal batteries to do continuity checks on the wires.Advanced Cable Testers: Advanced cable testers, such as the Fluke 620 LAN CableMeter®,perform basic cable testing functions and more.
The Fluke 620 Advanced cable testers can cost fromhundreds to thousands of U.S. dollars. Advanced cable testers will be used in future labs to do wire1-2CCNA 1: Networking Basics v 3.1- Lab 3.1.9bCopyright 2003, Cisco Systems, Inc.maps as well as other tasks. The 620 LAN CableMeter is a cable tester designed to verifyconnectivity of all LAN cable types. This rugged tester can measure cable length, test for faults andshow the distance to the defect. Open faults include opens, shorts, reversed, crossed, or split pairs.Each 620 LAN CableMeter comes with one cable identifier.The Fluke 620 is more advanced because it performs more functions:•Requires only single-person verification•Tests all LAN cable types, UTP, STP, FTP, Coax•Detects a multitude of wiring problems including open, short, crossed, reversed, split pair•Locates wiring or connection errors•Measures cable lengthPrior to starting the lab, the teacher or lab assistant should have basic cable testers or Fluke Cablemeters available for each team of students.
Also provided should be various lengths of wire withinduced problems. Work in teams of two. The following resources will be required:•Basic cable tester•Advanced cable tester, Fluke 620 or an equivalent•Two good Category 5 or higher cables, one crossover and one straight-through•Two bad Category 5 or higher cables, one with a break and one with a short.
Use different colorsor labels.Step 1 Test the CablesSimple cable tester: Refer to the instructions from the manufacturer. Insert the ends of the cable tobe tested into the jacks according to the instructions.Fluke 620: Insert the RJ-45 from one end of the cable into the UTP/FTP jack on the tester. Turn thedial to test. All conductors will be tested to verify they are not broken or shorted.Note: This test does not verify that the pins are connected correctly from one end to theother.For each test, insert the cable into the RJ-45 jack(s) of the cable tester. Record the results in thefollowing table.Color or cablenumberCategorytypeStraight-through orcrossover?Length ofcableTest resultsPass / FailCable #1Cable #2Cable #3Cable #42-2CCNA 1: Networking Basics v 3.1- Lab 3.1.9bCopyright 2003, Cisco Systems, Inc.Lab 3.1.9c Straight-Through Cable ConstructionObjective•Build a Category 5 or Category 5e Unshielded Twisted Pair (UTP) Ethernet network patch cableor patch cord.•Test the cable for continuity and correct pinouts, the correct color of wire on the right pin.BackgroundThe cable constructed will be a four-pair, eight-wire, straight-through cable, which means that thecolor of wire on Pin 1 on one end of the cable will be the same as that of Pin 1 on the other end.
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