Objectives of this Lab: The goal of this lab is to become familiar with building topologies in Packet Tracer and how to configure switches with the end devices such as PCs or Laptops. Instructions: • Read carefully before starting the lab. • These exercises are to be done individually. • You are supposed to provide the answers to the questions listed at the end of this document and upload the completed report to the Moodle. • Avoid plagiarism by copying from the Internet or from your peers. Your submitted work should be written by yourself. • Total Marks = 10 • Weightage = 2.5% • Deadline to submit your report is by 5pm Sunday 18 April. You must submit a word document that provides answers to the questions given at the end. Packet Tracer: Packet Tracer is a visual simulation tool designed by Cisco Systems that allows users to create network typologies and imitat
Lab 3: Introduction to Packet Tracer Lab Title: Introduction to Packet Tracer Total Marks= 10 Objectives of this Lab: The goal of this lab is to become familiar with building topologies in Packet Tracer and how to configure switches with the end devices such as PCs or Laptops. Instructions: • Read carefully before starting the lab. • These exercises are to be done individually. • You are supposed to provide the answers to the questions listed at the end of this document and upload the completed report to the Moodle. • Avoid plagiarism by copying from the Internet or from your peers. Your submitted work should be written by yourself. • Total Marks = 10 • Weightage = 2.5% • Deadline to submit your report is by 5pm Sunday 18 April. You must submit a word document that provides answers to the questions given at the end. Packet Tracer: Packet Tracer is a visual simulation tool designed by Cisco Systems that allows users to create network typologies and imitate modern computer networks. The software allows users to simulate the configuration of Cisco routers and switches using a simulated command line interface. Step 1: Start Packet Tracer Lab 3: Introduction to Packet Tracer Step 2: Choosing Devices and Connections We can begin building our network topology by selecting devices and the media in which to connect them. Several types of devices and network connections can be used. For this lab we will keep it simple by using End Devices, Switches, and Connections. Single click on each group of devices and connections to display the various choices. The devices you see may differ slightly. Step 3: Building the Topology – Adding Hosts Single click on the End Devices. Single click on the Generic host. Lab 3: Introduction to Packet Tracer Move the cursor into topology area. You will notice it turns into a plus “+” sign. Single click in the topology area and it copies the device. Step 4: Building the Topology – Connecting the Hosts to Switches Adding a Switch Select a switch, by clicking once on Switches and once on a 2950-24 switch. Add the switch by moving the plus sign “+” below PC2 and PC3 and click once. Lab 3: Introduction to Packet Tracer Connections contain different wired media. Most common examples are the straight-through cable and the crossover cable. Straight-Through Cable A straight through cable is a type of twisted pair cable that is used in local area networks to connect a computer to a network switches/ router. Crossover Cable A crossover Ethernet cable is a type of Ethernet cable used to connect computing devices together directly: e.g. two computers (via network interface controller) or two switches to each other. Connect PC2 to Switch0 by first choosing Connections. Click once on the Copper Straight-through cable. Perform the following steps to connect PC2 to Switch0: 1. Click once on PC2 2. Choose FastEthernet 3. Drag the cursor to Switch0 4. Click once on Switch0 and choose FastEthernet0/1 5. Notice the green link lights on PC2 Ethernet NIC and amber light Switch0 FastEthernet0/1 port. 6. After a about 30 seconds the amber light will change to green indicating that the switch is now ready to forward the frames. Lab 3: Introduction to Packet Tracer Repeat the steps above for PC3 connecting it to Port 3 on Switch0 on port FastEtherent0/2. (The actual switch port you choose does not matter.) Move the cursor over the link light to view the port number. Fa means FastEthernet, 100 Mbps Ethernet. Cisco CLI Architecture A Cisco IOS Switch command line interface can be accessed through a console connection, modem connection, or a telnet session. Regardless of which connection method is used, access to the IOS command line interface is generally referred to as an EXEC session. As a security feature, Cisco IOS separates EXEC sessions into two different access levels - user EXEC level and privileged EXEC level. User EXEC level allows a person to access only a limited amount of basic monitoring commands. Privileged EXEC level allows a person to access all Switch commands (e.g. configuration and management) and can be password protected to allow only authorized users the ability to configure or maintain the Switch. For example, when an EXEC session is started, the Switch will display a "Switch>" prompt. The right arrow (>) in the prompt indicates that the Switch is at the user EXEC level. The user EXEC level does not contain any commands that might control (e.g. reload or configure) the operation of the Switch. To list the commands available at the user EXEC level, type a question mark (?) at the Switch> prompt. 1 2 3 4 5 6 Lab 3: Introduction to Packet Tracer Critical commands (e.g. configuration and management) require that the user be at the privileged EXEC level. To change to the privileged EXEC level, type "enable" at the Switch> prompt. If an enable password is configured, the Switch will then prompt for that password. When the correct enable password is entered, the Switch prompt will change to "Switch#" indicating that the user is now at the privileged EXEC level. To switch back to user EXEC level, type "disable" at the Switch# prompt. Typing a question mark (?) at the privileged EXEC level will now reveal many more command options than those available at the user EXEC level. The text below illustrates the process of changing EXEC levels. Switch> enable Switch# disable Switch> Once an EXEC session is established, commands within Cisco IOS are hierarchically structured. To assist users in navigation through IOS CLI, the command prompt will change to reflect the position of a user within the command hierarchy. This allows users to easily identify where within the command structure they are at any given moment. The following table gives the summary of command prompts and the corresponding location within the command structure. Switch> - User EXEC mode Switch# - Privileged EXEC mode Switch(config)# - Configuration mode (notice the # sign indicates this is only accessible at privileged EXEC mode.) Table: IOS command prompt summary Lab 3: Introduction to Packet Tracer Today’s Lab: Today we are going to make a small network using switches in Cisco Packet Tracer. We will use 4 End Devices, and 3 Switches in total as shown in the figure below. Following is the IP Configuration Admin1 : 10.0.0.2 Admin2 : 10.0.0.3 Student1: 10.0.0.12 Student2 : 10.0.0.13 Note: Use the same subnet mask of 255.255.255.0 for all the four end devices. (Replace the student1 and student2 end devices and the right-side student switch to your name) To Configure IP addresses of End Device, we click from drawing window on end host and a menu pops up. If we go to 3rd tab (desktop only for PC and laptop) of it, we will find plenty of options for End host and we can set IP address there by clicking on IP configuration. Following is the Admin1 IP address setup. Lab 3: Introduction to Packet Tracer Double click on switch and its panel is opened and there we can access CLI as highlighted in the figure below. Enter once or twice to get the console for the switch configuration. In today’s lab, we will be going to perform the following tasks: 1. Change the hostname 2. Enable password 3. Show the running configuration Lab 3: Introduction to Packet Tracer 4. Encrypt the password 5. Setting the message of the day using banner motd # 1. Change the hostname Following are the commands you have to run on the switch to change the hostname of the switch. Switch>enable Switch#config terminal Switch(config)#hostname Admin_Switch Admin_Switch(config)#exit Admin_Switch#copy running-config startup-config (This command is used to save the configuration, make sure to run this command before closing the CLI window) 2. Enable password Admin_Switch>enable Admin_Switch#config terminal Admin_Switch(config)#enable password myPassword1 Admin_Switch(config)#enable secret myPassword Admin_Switch(config)#exit Admin_Switch#copy running-config startup-config 3. Show the running configuration We can see the running configuration at any time which shows the overall configuration of your switch. Admin_Switch#show running-config Lab 3: Introduction to Packet Tracer 4. Encrypt the password All passwords configured on the switch, with the exception of the passwords configured with enable secret password, are stored in clear-text in the device configuration file. This means that all that attacker needs to do to find out the passwords is to run the show running- config command as shown below in the figure To encrypt the enable password, we have to run the following command Admin_Switch#config terminal Admin_Switch(config)# Admin_Switch(config)#service password-encryption