Simple Routing

Summary We simulated a packet's journey through a network. This lab also further explains how a default gateway works.

https://docs.google.com/document/d/1-4P4ImNVDLD8lYO4qXLWoRb1Oj0D9iAVMzON0_m-Lqg/edit

Procedure

Part 1 - Configuring the Network

1. Start by downloading and opening the Packet Tracer file for this lab: lab41-starter.pkt

2. Assign the following IP addresses and subnet masks to the PCs mask? It's pretty self explanatory how to do this (config tab on the PCx)

PC0

IP address: 192.168.1.10

Subnet Mask: 255.255.255.0

PC1

IP address: 192.168.2.20

Subnet Mask: 255.255.255.0

PC2

IP address: 192.168.3.30

Subnet Mask: 255.255.255.0

3. Since we'll be pinging across different networks, we'll need to define the gateway addresses for our PCs. To set the gateway for a PC, choose the Config tab, and then choose 'Settings' in the left-hand menu. You can enter the gateway IP in the 'Gateway' field (make sure the 'Static' button above it is selected).

4. Enter the following gateway IPs for each PC:

PC0: 192.168.1.1

PC1: 192.168.2.1

PC3: 192.168.3.1

5. Now, we'll need to set the interface that each PC is connected to on the multilayer switch to match the gateway IP we just defined, since this switch also has layer 3 routing capabilities and will serve as the gateway for all three machines. Click on the multilayer switch, choose the Config tab in the window that appears, and then pick the FastEthernet interface that you want to configure

6. Enter the following IPs on these interfaces:

FastEthernet0/1: 192.168.1.1

FastEthernet0/2: 192.168.2.1

FastEthernet0/3: 192.168.3.1

All subnet masks will be 255.255.255.0

Note that because each port is a distinct interface, they all have to be given their own address.

6. Once all of the interfaces are configured, try pinging PC1 and PC2 from PC0. If configured correctly, the pings should succeed!

Part 2: Packet Tracer Simulation Mode

1. Click on the Simulation button in the bottom-right corner of the Packet Tracer window.

2. A Simulation panel will appear on the right side of the window. Since Packet Tracer will simulate many protocols by default, click the 'Show All/None' button at the bottom of this window, and then click the 'Edit Filters' button. Check the ICMP box in the IPv4 tab of the window that pops up.

3. Now, ping PC1 from PC0. The initial ping packet should appear in the simulation window. Click the '►|' button a few times until the packet reaches PC1 - you should see the following packets in the simulation window:

4. If you click on the packet at the Multilayer Switch, you'll receive a summary of the OSI information the packet contains as it both arrives at and leaves the switch. In particular, at layer 2 you'll see something like 'AAAA.AAAA.AAAA >> BBBB.BBBB.BBBB' - this indicates that the packet is being sent from the MAC address AAAA.AAAA.AAAA to the MAC address BBBB.BBBB.BBBB. If you click on the Inbound and Outbound detail tabs, you can see how this information is specifically formatted within each packet.