第 1 页 共 13 页LAB 4 Cabling LANs and WANsPART 1 RepeatersObjective: Create a simulated network topology Apply IP addresses to workstations Be familiar with the function of a repeater Understand the Four Repeater Rule Test the simulated topology Step 1Create the topology shown in the diagram in Packet Tracer. After connecting all the devices, assign each PC with a valid IP address and subnet mask. (You can use any IP addresses as long as they belong to the same network.)Step 2a) Click on the Simulation tab to start creating a scenario.b) Add a packet and click on source PC 0 and then click on destination PC 1. Add another packet from PC 1 to PC 2.c) Click play to watch the simulation.d) Take note of the time it takes for each packet to reach its destination. (Having more repeaters between workstations adds latency to the packets.)Step 3a) Click once on the arrow on the left of the play button to go back one second (The number in the Time box should be “6”)b) Add a packet from PC 2 to PC 1.c) Click on the Topology tab. Remove a connection then add another repeater anywhere between Switch 0 and PC 2. Re-connect the devices.第 2 页 共 13 页d) Click on the Simulation and hit the play button to watch the simulation. (Latency results in collision.)PART 2 Repeaters and HubsInformation:1. This topology consists of 8 hosts along with 2 hubs and 1 repeater in the network. 第 3 页 共 13 页Tips:a) The Packet Tracer “i” located on the upper right of each page and device will give information pertaining to that certain device or topology.b) In simulation, the “i” next to the scenario drop down list will give information about the specific scenario.c) In simulation, clicking on the packets will show OSI layer information.Procedures:a) In the topology mode, add three (3) additional repeaters between the two (2) hubs.b) In simulation mode, create a new scenario.c) Send a packet from PC4 to PC0 and a packet from PC5 to PC1 at different times so that the packets will not collide.d) Before running the simulation, click on the individual packets on PC4 and PC5 to review the packet and OSI information. Next, run the simulation.e) After the first simulation, repeat step 3 except the packets does collide this time. Then repeat step 4.f) After the packets arrive to Hub1, click on the packet that leaves Hub1 and propagates to Repeater0.Questions:a) What is the purpose of a hub and repeater in this network?集线器：对接收到的信号进行再生整形放大，以扩大网络的传输距离，同时把所有节点集中在以它为中心的节点上；中继器：主要功能是通过对数据信号的重新发送或者转发，来扩大网络传输的距离。b) What type of medium is being used to connect the hosts to the hubs and the repeater to the hubs? twisted pairc) How many collision domain(s) does this network contain?2 个冲突域PART 3 Wireless第 4 页 共 13 页Information:1. This topology consists of a workstation, a laptop, a server, a printer, and an access point. The entire network is wireless. Tips:a) The Packet Tracer “i” located on the upper right of each page and device will give information pertaining to that certain device or topology.b) In simulation, the “i” next to the scenario drop down list will give information about the specific scenario.c) In simulation, clicking on the packets will show OSI layer information.Procedures:a) Review Scenario 2 in simulation mode.b) Take into consideration that the connected devices doesnt have any idea that the collisions are occurring.c) What if the devices continue sending packets to each other indefinitely? A simulation can be seen by creating packets between the devices so that multiple collisions happen one after another. Think of the latency this type of situation creates.Questions:a) What types of signals are wireless connections capable of?语音和数据信号b) In what ways are access points related or different compared to other networking devices such as hubs and switches?般俗称为网络桥接器，顾名思义即是当作传统的有线局域网络与无线局域网络之桥梁，因此任何一台装有无线网卡之 PC 均可透过 AP 去分享有线局域网络甚至广域网络之资源。除此之外，AP 本身又兼具有网管之功能，可针对接有无线网络卡之 PC 作必要之控管。c) What security issue(s) arises when using wireless connectivity?非授权用户的接入、信息泄露、信号干扰、伪装地址和拦截对话、高级攻击第 5 页 共 13 页d) In what situations does wireless connectivity have an advantage over wired and vice versa?安装便捷、使用灵活、易于扩展PART 4 Bridges and SwitchesInformation:1. This topology consists of 14 hosts along with 4 switches and 2 bridges in the network. Tips:a) The Packet Tracer “i” located on the upper right of each page and device will give information pertaining to that certain device or topology.b) In simulation, the “i” next to the scenario drop down list will give information about the specific scenario.c) In simulation, clicking on the packets will show OSI layer information.d) In simulation, clicking on the bridges and switches will load up the MAC address tables.Procedures:a) In the topology mode, Switch0s Fast Ethernet port 6 is disabled. As a result, the link between Switch0 and Bridge0 is down.b) Still in topology mode, click on Switch0 and then click on Fast Ethernet port 6. Enable the port by turning it on.c) Now go into simulation mode. As yo