How does packet tracer work

Your network should look like the following image:. At this point, the router still needs be turned on. To setup the router, click on the router icon so that the configuration menu is raised. Here you will need to verify that the router is turned on. If the router is on there will be a small green light below the switch:. The next step is to open Ethernet ports to allow communication. Currently they are physically connected by inactive in a state referred to as administrative shut down.

Click on the CLI tab to raise the configuration menu. The configuration menu acts the same as Cisco IOS:. Remember to enter a different IP address! Once you have completed these steps, the router is configured! The final step is to configure the gateway on each desktop computer.

The gateway is the address assigned to the Ethernet port that the desktop is connected to. Click on PC0 to view the configuration menu. Go to global sendings and find the gateway field. Enter Repeat the process for PC1 but use To do this you need to click the packet icon the envelope icon from the menu on the right hand side of the screen:. Now click on PC0 and PC1.

Syntax errors can often cause connections to fail. While this is a limited topology with two computers and enterprise networks are considerably more complex, this will help to teach you some basic principles that you can take with you when managing larger networks. There are a number of competitors to Packet Tracer that are worth considering. NetSim is designed specifically for Cisco Certification training, with topology creation and the ability to share labs and topologies with the NetSim community.

The price of Netsim varies depending on the package you want. In total there are three packages available to purchase;. You can view more information on the pricing options of NetSim via this link here. Dynamips is a network simulation program that was designed specifically to help imitate Cisco devices. You can download it for free via this link here. Cisco Packet Tracer as the name suggests, is a tool built by Cisco.

This tool provides a network simulation to practice simple and complex networks. As Cisco believes, the best way to learn about networking is to do it. Attention reader! The main purpose of Cisco Packet Tracer is to help students learn the principles of networking with hands-on experience as well as develop Cisco technology specific skills. Since the protocols are implemented in software only method, this tool cannot replace the hardware Routers or Switches.

Interestingly, this tool does not only include Cisco products but also many more networking devices. Skip to content. After adding a device from here, we will be able to control it from the drawing window. As from the screenshot, this toolbar is divided into two parts.

On the left, we have two rows of icons: the top category is on top and the sub-category is on the bottom. If you hover any icon on these two rows you will see the description in the white rectangle that separates the row. Depending on the combination of category and sub-category, Packet Tracer will present you with different devices on the right part of the toolbar. There is no point in listing all the devices available in this article, it is a lot easier for you to explore the various tabs.

However, Packet Tracer contains several models of switches, routers, end-devices, and — from version 7 — IoT devices. Above everything else, we are going to use network devices.

Then, there are two other categories we have to use with them: end-devices and connections. In end-devices the computer icon , you can find computers, smartphones and servers. Connections are instead represented by an orange bolt, and you use them to interconnect other devices. Once you add a device to the drawing window you will be able to control it. For simplicity, we put them in a triangle shape. Now that we added the devices, we need to connect them together.

Now we have several possibilities, among them you can make Packet Tracer decide which cable suits best every condition. However, for today we are going to use a simple Copper straight-through cable the black solid line.

You know from the previous articles that a device can have multiple NICs , so how do we select the one to plug the cable into? It is extremely simple. Just select the cable, then click on a device you want to connect: a menu with all the available interfaces will open. As soon as you connect the cables, you will see some colored dots on their ends, as in picture below.

Data can travel over a cable only if the two dots on it are green. However, when you connect the cables you will see the switch side turning orange. This is because the switch is doing some checks before turning on the interface, so you just have to wait or fast-forward the time.

The dot indicating the port-status refers to the interface status of the closest device. It can be of three different colors. Once your ports become green, you are ready to see how we configure devices in Cisco Packet Tracer. In Packet Tracer, you are going to work with a huge variety of devices. Therefore, you are going to face different ways on configuring devices, depending on the device itself.

Two major device categories exist: network devices and end-devices , each with its own configuration. You are going to configure network devices by using the CLI Command-Line Interface , where you interact with the device using text only.

To reach the CLI of a network device, just click on it with the select tool. A new window will pop-up, and from its tabs you just have to select CLI. This way, you will gain console access to the device. In this tutorial, we are not going to configure any network device. The only switch we added will work out-of-the-box , no configuration needed.

Instead, read on to see how we will configure end devices. Configuring end devices is relatively simple, as you can do it completely from the Graphical Interface of Cisco Packet Tracer. The mechanism is always the same, just click on the device you want to configure and a new window will pop-up. From that window, navigate to the config tab. Then, configure the PC on the left with an IP address of After that, configure the other PC with an IP address of In networking, we call capture the content of a packet that we catch for debugging purposes.

Packet tracer allows us to do so in the simulation mode, but we must create some traffic to capture. The first thing we want to do is to switch to Simulation mode. Now, nothing can happen unless we manually forward the time. Anyway, before that we need to configure capture filters to tell Packet Tracer which type of packets we want to see. By default, Packet Tracer will listen to everything.

Now, we are ready to generate the traffic to capture. For this example, we are going to generate some traffic going from a PC to the other. The traffic we are going to create is ICMP, and we are going to do so with a ping command. Once the prompt opens, ping the IP address of the other PC. In this case, we are going to do that with the command ping Now, nothing will happen because Packet Tracer is waiting for us to forward time. Meanwhile, if you check the drawing area, you will see that two packets are buffered on your PC waiting to go onto the cable.