LAB 5‐2 - Dleifnesor/NET-215 GitHub Wiki

Packet Tracer - Simple 2 Router Lab

Objective

Identify the need for routing protocols and their role in internetworks with multiple routers.

Goals

  • Observe the need and purpose of routing protocols
  • Extend the switched network from the previous lab (402) to include a second router
  • Configure RIP to support route propagation for non-directly connected networks

Initial Steps

  1. Open your Packet Tracer File from Lab 5-1.
  2. Add another network/LAN:
    • To the right of the 20.20.20.0/24 network, add:
      • A Cisco 2950-24 switch
      • 2 new PCs (PC5 and PC6)
    • This LAN will have the network address: 30.30.30.0/24 (netmask 255.255.255.0).
    • Configure the workstations with IP addresses 30.30.30.105 and 30.30.30.106 with a gateway of 30.30.30.1.
    • Connect PC5 & PC6 to the new 2950-24 Switch using a straight-through cable.
  3. Add another 1841 Router for that LAN:
    • Configure Fa0/0 with IP 30.30.30.1 and mask 255.255.255.0.
    • Connect the switch to the router's Fa0/0.
    • Verify that PC5 and PC6 can ping one another and their gateway.

Preparing to Connect the Two Routers - Save Configuration

  1. The routes will be on their own network connected via serial lines.
  2. Save the current configuration on both routers: 
    Router# copy running-config startup-config

Add Serial Ports to Routers

  1. Select the Physical Tab on Router 0.
  2. Click the Power Button to Off.
  3. Drag a WIC-1T interface card into the left slot (Slot 1).
  4. Turn the power back On.
  5. Repeat these steps for Router 1.

Connecting the Routers

  1. Configure Router0 (Config Tab → Serial 0/1/0):
    • IP: 1.1.1.1
    • Mask: 255.255.255.252
    • Enable the interface
  2. Configure Router1 (Config Tab → Serial 0/1/0):
    • IP: 1.1.1.2
    • Mask: 255.255.255.252
    • Enable the interface
  3. Connect the routers using the Serial cable (red lightning bolt) between Serial 0/1/0 interfaces.

Testing Communication

  1. PC0 to PC4 should be able to ping each other.
  2. PC5 and PC6 should be able to ping each other.
  3. PC0-4 should not be able to ping PC5-6.
  4. On Router0, check the routing table: 
    Router# show ip route
    • Record the networks showing up in Router 0's routing table.
  5. On Router1, check the routing table: 
    Router# show ip route
    • Record the networks showing up in Router 1's routing table.

Need for Routing Protocols

  • The routers need to exchange routing information to enable communication between all PCs.
  • We will use RIP (Routing Information Protocol).
  • RIP allows routers to broadcast their routing tables.

Configuring RIP

  1. Router 0:
    • In Config → RIP, add networks: 1.1.1.0, 10.10.10.0, 20.20.20.0.
    • Note: RIPv1 assumes classful addresses, converting them as necessary.
  2. Router 1:
    • In Config → RIP, add networks: 30.30.30.0, 1.1.1.0.
  3. Save the configuration on both routers: 
    Router# copy running-config startup-config
  4. Use "Fast Forward Time" to allow RIP updates to propagate.
  5. All PCs should now be able to ping each other.

Validate Routing Tables and RIP

  1. On Router 0, capture the routing table: 
    Router# show ip route
    • Submit a screenshot showing all networks.
  2. On Router 1, capture the routing table: 
    Router# show ip route
    • Submit a screenshot showing all networks.
  3. Submit a successful ping between PC0 and PC6.

Packet Capture - RIP Analysis

  1. Switch to Simulation Mode (stopwatch icon).
  2. Click "Edit Filters" and uncheck:
    • IPV4-ARP
    • MISC-STP
    • MISC-CDP
    • MISC-DTP
  3. Start Auto Capture/Play for a few minutes.
  4. Identify a Router0 to Router1 RIP packet.
  5. Click on the colored block for the packet.
  6. Scroll through the Inbound PDU Details.
  7. Submit a screenshot of the Inbound PDU Details.
  8. Answer the following questions:
    • What is the Destination IP address (IP Header) of that packet?
      • 224.0.0.9 (Multicast address for RIP updates)
    • What network information is included in the "Rip Route Packet" section?
      • The RIP packet contains:
        • Network addresses
        • Subnet masks
        • Hop count to reach those networks
      • This data enables routers to learn about connected networks and propagate routes dynamically.