How to View Protocol Data Units using cisco packet tracer?

In this post we'll learn How to View Protocol Data Units using cisco packet tracer?
This system is provided by cisco. In the last of the post, you may download the packet tracer provided by cisco. Now lets goto the main post :
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Introduction:

Wireshark provides the ability to capture and display all of the network traffic entering and leaving the PC on which it is installed through a network interface. Simulation mode in Packet Tracer captures all network traffic flowing through the entire network but only supports a limited number of protocols. To come as close as possible to approximating Lab 2.6.2 we will use a network consisting of a PC that is directly connected to a web server and capture a ping to the server from the PC's command prompt and a request for a web page using a URL.

Objectives:

1. Capture a ping from a PC command prompt. 

• Run the simulation and capture the traffic. 
• Examine the captured traffic.
2. Capture a web request using a URL from a PC. 

• Run the simulation and capture the traffic. 
• Examine the captured traffic.

Task 1: Capture a ping from a PC command prompt.

Step 1 – Run the simulation and capture the traffic.

In the far lower right of the PT interface is the toggle between Realtime and Simulation mode. Click on Simulation mode. 
Click on the PC. Choose the Desktop tab. Open the Command Prompt. Enter the command ping 192.168.1.2, the IP address of the server. Pressing theEnter key will initiate four ICMP echo requests. Minimize the PC configuration window. Two packets appear in the Event List, the first ICMP echo request and an ARP request needed to resolve the IP address of the server to its hardware MAC address.
Click the Auto Capture / Play button to run the simulation and capture events. Click OK when the "No More Events" message is reached.

Step 2 – Examine the captured traffic.

Find the first packet in the Event List, and click on the colored square in theInfo column. When you click on the Info square for a packet in the event list thePDU Information window opens. The OSI model organizes this window. In the case of the first packet we are viewing, notice the ICMP echo request (at Layer 3) is encapsulated at Layer 2. If you click on these layers, the algorithm used by the device (in this case, the PC) is displayed. View what is going on at each layer. 
When opening the PDU Information window, the default is the OSI Modelview. Now click on the Outbound PDU Details tab. Scroll down to the bottom of this window, and you will see that the ICMP echo request is encapsulated as data in an IP packet. 
Examine the PDU information for the remaining events in the exchange.
Close the PDU information window and reset the simulation by clicking theReset Simulation button.

Task 2: Capture a web request using a URL from a PC.

Step 1 – Run the simulation and capture the traffic.

Click on the PC. Close the Command Prompt window. Open the Web Browser. Enter www.example.com into the browser. Clicking on Go will initiate a web server request. Minimize the Web Client configuration window. A packet appears in the Event List, a DNS request needed to resolve the URL to the IP address of the server.
Click the Auto Capture / Play button to run the simulation and capture events. Click OK when the "No More Events" message is reached.

Step 2 – Examine the captured traffic.

Examine the PDU information for the events in this exchange.
Compare and contrast Wireshark and Packet Tracer. "

Packet tracer file : How to View Protocol Data Units using cisco packet tracer?