Cisco CCNA Exploration 4.0 Chapter2 PT 2.7.1

Paket Tracer Exploration 2.7.1

2.7.1: Skills Integration Challenge-Examining Packets

Topology Diagram:

A nearly complete standard lab topology is provided as starting point.

Device	Interface	IP Address	Subnet Mask	Default Gateway
R1-ISP	Fa0/0	192.168.254.253	255.255.255.0	N/A
	S0/0/0	10.10.10.6	255.255.255.252
R2-Central	Fa0/0	172.16.255.254	255.255.0.0	N/A
	S0/0/0	10.10.10.5	255.255.255.252
S1-Central	VLAN 1	172.16.254.1	255.255.0.0	172.16.255.254
PC 1A	NIC	172.16.1.1	255.255.0.0	172.16.255.254
PC 1B	NIC	172.16.1.2	255.255.0.0	172.16.255.254
Eagle Server	NIC	192.168.254.254	255.255.255.0	192.168.254.253

Learning Objectives:

• Complete the Topology
• Add Simple PDUs in Realtime Mode
• Analyze PDUs in Simulation Mode
• Experiment with the model of the standard lab setup

Background:

Throughout the course, you will be using a standard lab setup created from actual PCs, servers, routers, and switches to learn networking concepts. In this activity, you will continue learning how to build and analyze this standard lab topology. If you have not done so already, you are encouraged to examine the Help files available from the Help Pull-down menu at the top of the Packet Tracer GUI. Resources include a "My First PT Lab" to help you learn the basic operation of Packet Tracer, tutorials to guide you through various tasks, and information on the strengths and limitations of using Packet Tracer to model networks.

This activity will provide an opportunity to explore the standard lab setup using Packet Tracer simulator. Packet Tracer has two file formats it can create: .pkt files (network simulation model files) and .pka files (activity files for practice). When you create your own networks in Packet Tracer, or modify existing files from your instructor or your peers, you will often use the .pkt file format. When you launched this activity from the curriculum, these instructions appeared. They are the result of the .pka, Packet Tracer activity file format. At the bottom of these instructions are two buttons: Check Results (which gives you feedback on how much of the activity you have completed) and Reset Activity (which starts the activity over, if you want to clear your work or gain more practice).

Task 1: Complete the Topology

Add a PC to the workspace.

Configure it the following parameters: IP Address 172.16.1.2, Subnet Mask 255.255.0.0, Default Gateway 172.16.255.254, DNS Server 192.168.254.254, Display Name "1B" (do not include the quotation marks). 

Connect PC 1B to the Fa0/2 port of the S1-Central Switch and check your work with the Check Results button to see that the topology is complete.

Task 2: Add Simple PDUs in Realtime Mode

Wait until the switch link lights are green. Using the Add Simple PDU,

send a test message between PC 1B and Eagle Server. Note that this packet will appear in the lower right as a user created PDU that can be manipulated for testing purposes. The first time you issue this one-shot ping message, it will show as Failed--this is because of the ARP process, which will be explained later. Double clicking the "Fire" button in the PDU List Window, send this single test ping a second time. This time it will be successful. Please do this prior to the next task.

Task 3: Analyze PDUs in Simulation Mode (Packet Tracing)

Switch to simulation mode. Use the Capture / Forward button to move the packet through the network.

Click on the packet envelope, or on the colored square in the Info column of the Event List, to examine the packet at each step in its journey. 

Task 4: Experiment with the model of the standard lab setup

The standard lab setup will consist of two routers, one switch, one server, and two PCs. Each of these devices is pre-configured. Try creating different combinations of test packets and analyzing their journey through the network.

Reflection:

If you have not already done so, you are encouraged to obtain Packet Tracer from your instructor and complete My First PT Lab (available by using the HELP Pulldown Menu and choosing CONTENTS). 

Cisco CCNA Exploration 4.0 Chapter2 PT 2.6.2

Paket Tracer Exploration 2.6.2

Activity 2.6.2: 
Using Packet Tracer to View Protocol Data Units

Addressing Table

This activity does not include an addressing table.

Learning Objectives

• Capture a ping from a PC command prompt
• Run the simulation and capture the traffic
• Examine the captured traffic
• Capture a web request using a URL from a PC
• Run the simulation and capture the traffic
• Examine the captured traffic

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.

At the beginning of this task your completion rate should be 100%. The devices are configured and the purpose of this activity is to examine the flow of traffic between devices.

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 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 the Enter 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 the colored square in the Info column.

When you click the Info square for a packet in the event list the PDU 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 each of 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 theOSI Model view. Now click 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 the Reset Simulation button.

 At the end of this task your completion rate should remain at 100%.

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

Step 1. Run the simulation and capture the traffic.

Click the PC. Close the Command Prompt window. Open the Web Browser. Enter www.example.com into the browser. Clicking 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.

  At the end of this task your completion rate should remain at 100%.

 

Cisco CCNA Exploration 4.0 Chapter2 PT 2.6.1

Paket Tracer Exploration 2.6.1

Activity 2.6.1: 
Topology Orientation and Building a Small Network

Addressing Table

This lab does not include an addressing table.

Learning Objectives

• Correctly identify cables for use in the network
• Physically cable a peer-to-peer
• Verify basic connectivity on each network

Introduction:

Many network problems can be fixed at the Physical layer of a network. For this reason, it is important to have a clear understanding of which cables to use for your network connections.
At the Physical layer (Layer 1) of the OSI model, end devices must be connected by media (cables). The type of media required depends on the type of device being connected. In the basic portion of this lab, straight–through or patch—cables will be used to connect workstations and switches.In addition, two or more devices communicate using assigned addresses. The Network layer (Layer 3) requires a unique address (also known as a logical address or IP Addresses), which allows the data to reach the appropriate destination device.
Addressing for this lab will be applied to the workstations and will be used to enable communication between the devices.

Task 1: Create a Peer-to-Peer Network

Step 1. Select a Lab Partner

Step 2. Obtain equipment and resources for the lab.

Equipment needed:

• 2 workstations
• 1 Ethernet cable

 At the end of this task your completion rate should be 0%.

Task 2: Identify the Cables used in a Network

Before the devices can be cabled, you will need to identify the types of media you will be using. The cables used in this lab are crossover and straight-through.
Use a crossover cable to connect two workstations to each other through their NIC’s Ethernet port. This is an Ethernet cable. When you look at the plug you will notice that the orange and green wires are in opposite positions on each end of the cable.
Use a straight-through cable to connect the router’s Ethernet port to a switch port or a workstation to a switch port. This is also an Ethernet cable. When you look at the plug you will notice that both ends of the cable are exactly the same in each pin position.

Step 1. Cable the Peer-to-Peer Network.

Using the correct Ethernet cable, connect two workstations together. Connect one end of the cable to the NIC port on PC1 and the other end of the cable to PC2.Which cable did you use? stright-throught cable

At the end of this task your completion rate should be 33%.

Task 3: Configure addresses and test

Step 1. Apply a Layer 3 address to the workstations.

To complete this task, you will need to follow the step-by-step instructions below.

• Click the PC you want to assign an address to.
• Click the Desktop tab
• Click the IP Configuration tab
•  In the IP address box, enter the IP address 192.168.1.2 for PC1. (Enter the IP address 192.168.1.3 for PC2.)
•  Press the tab key and the Subnet mask is automatically entered. The subnet address should be 255.255.255.0. If this address is not automatically entered, enter this address manually
• Close the IP configuration window by clicking on the X

Step 2. Verify connectivity.

To test Connectivity follow the following instructions:

• Click PC1
• Click the Desktop tab
• Click the Command Prompt tab
• Type ping 192.168.1.3 then press enter

What is the output of the ping command? request timed out
If the ping command displays an error message or doesn’t receive a reply from the other workstation, troubleshoot as necessary. Possible areas to troubleshoot include:

• Verifying the correct IP addresses on both workstations
• Ensuring that the correct type of cable is used between the workstations

What is the output of the ping command if you unplug the network cable and ping the other workstation? request timed out

At the end of this task your completion rate should be 100%.

Cisco CCNA Exploration 4.0 Chapter2 PT 2.4.8

Activity 2.4.8: Use of the TCP/IP Protocols and the OSI Model in Packet Tracer

Learning Objectives

• Explore how PT uses the OSI Model and TCP/IP Protocols
• Examine Packet Processing and Contents

Introduction:

In Packet Tracer simulation mode, detailed information about packets and how they are processed by networking devices may be viewed. Common TCP/IP Protocols are modeled in Packet Tracer, including DNS, HTTP, TFTP, DHCP, Telnet, TCP, UDP, ICMP, and IP. How these protocols are used by networking devices in creating and processing packets is displayed, in Packet Tracer, using a representation of the OSI Model. The term protocol data unit, or PDU, is a generic description of what are known as segments at the transport layer, packets at the network layer, and frames at the data link layer.

Task 1: Explore the PT interface

Step 1. Examine the Help Files and Tutorials

From the pull down menu, choose Help->Contents. A web page will open. From the left frame, choose Operating Modes->Simulation Mode. If not already familiar, read about simulation mode.

 

Step 2. Switching from Realtime to Simulation Mode

In the far lower right of the PT interface is the toggle between Realtime and Simulation mode. PT always starts in Realtime mode, in which networking protocols operate with realistic timings. However, a powerful feature of Packet Tracer allows the user to "stop time" by switching to Simulation mode. In Simulation mode, packets are displayed as animated envelopes, time is event driven, and the user can step through networking events. Click the Simulation mode icon to switch from Realtime mode to Simulation mode.

Task 2: Examine Packet Contents and Processing 

Step 1. Creating a Packet and Accessing the PDU Information Window

Click the Web Client PC. Choose the Desktop tab. Open theWeb Browser. Enter the IP address of the Web Server into the browser, 192.168.1.254. 

 

 

Clicking Go will initiate a web server request. Minimize the Web Client configuration window. Since time in simulation is event driven, you must use the Capture/Forward button to display network events. Two packets appear in the event list, one of which has an eye next to it. An eye next to a packet means it is displayed as an envelope on the logical topology. Find the first packet in the Event List, and click the colored square in the Info column. 

 

  
Step 2. Investigating device algorithms in the OSI Modelview

When you click the Info square for a packet in the event list, or if you click a packet envelope displayed on the logical topology, thePDU Information window opens.

 The OSI model organizes this window. In the case of the first packet we are viewing, notice the HTTP request (at Layer 7) is then encapsulated, successively, at Layers 4, 3, 2, and 1. If you click through these layers, the algorithm used by the device (in this case, the PC) is displayed. View what is going on at each layer--this will be the subject of much of the rest of the course. 

Step 3. Inbound and Outbound PDUs

When opening the PDU Information window, the default is the OSI Model view. Now click the Outbound PDU Details tab.

 

Scroll down to the bottom of this window. 

 

There you will see that HTTP (the web page request that started this series of events) is encapsulated as data in a TCP segment, which in turn is encapsulated in an IP packet, which in turn is encapsulated in an Ethernet frame, which in turn is transmitted as bits on the medium. 

If a device is the first device involved in a series of events, packets at that device will only have an Outbound PDU Details tab; if a device is the last device in a series of events, packets at that device will have only an Inbound PDU Details tab.

 

In general, you will see both Outbound and Inbound PDU details, which give details about how Packet Tracer is modeling that device. 

Step 4. Packet tracing: animations of packet flow

The first time through a packet animation, you are actually capturing the packets, as in a protocol sniffer. Hence, theCapture/Forward button means "Capture" one set of events at a time. Step through the web page request. Note that you are only displaying HTTP-related packets; but other protocols like TCP and ARP also have packets that are not being displayed. At any time in your packet capture, you can open the PDU Informationwindow. Run through the entire animation until the "No More Events" message is reached. Experiment with this packet tracing process -- running the animation again, examining packets, predicting what will happen next, and investigating your predictions.

Cisco CCNA Exploration 4.0 Chapter2 PT 2.2.4

Paket Tracer Exploration 2.2.4

Activity 2.2.4: Network Representations

Addressing Table:

This Lab does not include an Addressing Table.

Learning Objectives:

• Explore the PT interface
• Locate the key components used to place device symbols in the logical workplace
• Examine the devices that can be placed in the logical workplace and their symbols
• Place and connect devices
• Add device symbols to the logical workplace
• Connecting devices in the logical workplace using auto connection

Introduction:

Packet Tracer is a network simulator that allows you create a simulated network, configure the devices in the network, test the network, and examine the traffic in the network. The first step in creating a simulated network in Packet Tracer is to place the devices in the logical workplace and connect them together. Packet Tracer uses the same symbols as are used throughout the curriculum. Match the icons in PT with the symbols in the symbol list.

Task 1: Explore the PT interface

Step 1. Logical Workspace

When Packet Tracer starts, it presents a logical view of the network in Realtime mode. The main part of the PT interface is the Logical Workplace. This is the large blank area where devices can be placed and connected.

Step 2. Device Symbols

The lower left portion of the PT interface, below the yellow bar, is the portion of the interface that you use to select and place devices into the logical workplace. The first box in the lower left contains symbols that represent groups of devices. As you move the mouse pointer over these symbols, the name of the group appears in the text box in the center. When you click on one of these symbols, the specific devices in the group appear in the box to the right. As you point to the specific devices, a description of the device appears in the text box below the specific devices. Click on each of the groups and study the various devices that are available and their symbols.

Task 2: Add devices to the logical workplace

Step 1. Selecting and Placing Devices

To add a device to the logical workplace click on the specific device symbol, point to where you want to place the device in the logical workplace (the pointer becomes a crosshair), and click. Locate and place the following devices in a horizontal row across the logical workplace, with about an inch between them, in order from left to right:

• a server
• a 2960 switch
• an 1841 router
• a hub
• an IP phone
• a PC

 Step 2. Connect the devices using auto connect

Click on the connections group symbol. The specific connection symbols provide different cable types that can be used to connect devices. The first specific type, the gold lightning bolt, will automatically select the connection type based on the interfaces available on the devices. When you click on this symbol, the pointer resembles a cable connector. To connect two devices click the auto connection symbol, click the first device, and then click the second device. Starting with the server, connect each device to the device to its right using the auto connection symbol.

 Step 3. Packet Tracer Scoring

Packet Tracer activities can be configured to score your work. To check your configuration, click the Check Results button below.

At the end of this task your completion rate should be 100%.