27 Dynamic Networking – Routing Information Protocol

As demonstrated in the previous lab, routers need to be told about distant networks in order to communicate with devices 1+ hops away. Doing this task manually is tedious and highly prone to human error, especially as networks start increasing in size. As a result, the Routing Information Protocol (RIP) was developed to allow routing devices to advertise their routing tables with their surrounding neighbors autonomously. Not only did this save configuration time, but it allowed routers to essentially re-calibrate themselves even as devices were added or removed over time.

Estimated time for completion: 15 minutes

Learning Objectives

• Implement the RIPv2 network routing protocol
• Practice using DHCP from a remote server
• Determine a network topology from a captured network packet

Prerequisites

• Chapter 26 – Static Networking Part 2

Deliverables

3 Screenshots are required to consider this lab complete:

• Screenshot of GNS3 workspace (LANS labeled with correct IPs and Subnets)
• Screenshot of DHCP configuration settings
• Screenshot of Wireshark packet showing RIPv2 network advertisement for all networks

Resources

• MikroTik RouterOS Documentation – RIP – https://help.mikrotik.com/docs/display/ROS/RIP
• MikroTik Router OS Documentation – RouterOSv7 changes to RIP – https://help.mikrotik.com/docs/display/ROS/Moving+from+ROSv6+to+v7+with+examples

Contributors and Testers

• Dante Rocca, Cybersecurity Student, ERAU-Prescott

Phase I – Building the Network Topology

The following steps are to create a baseline for completing this lab. It makes assumptions about learner knowledge from completing previous labs.

By the end of this lab your network will look like the following:

1. Open GNS3
   1. Open the previous Chapter 26 lab
   2. Save it as a new project: LAB_13
2. Modify the network environment:
   1. Remove the manually assigned static routes from Router1

      > ip route remove 0,1,2,3

      

   2. Repeat for the other two routers
3. Label and organize your network as necessary

1. Initialize a Wireshark capture between Router1 and Router2
2. Create a new RIPv2 instance on Router1

   > routing rip instance add name=RIP-ROUTER-01 redistribute=connected,rip

   > routing rip interface-template add interfaces=all instance=RIP-ROUTER-01

3. Create a new RIPv2 instance on Router2

   > routing rip instance add name=RIP-ROUTER-02 redistribute=connected,rip

   > routing rip interface-template add interfaces=all instance=RIP-ROUTER-02

4. Focus on the Wireshark capture window
   1. You should start to see RIPv2  Request and Response messages being exchanged to the IP 224.0.0.9 over port 520
      

      

   2. Opening any one of these packets will reveal the routing table being distributed
      

      

   3. The recipient routers will use this information to update their own routing tables

      > ip route print

      

5. Configure RIPv2 on Router3
6. Test the network’s new ability to dynamically update its routes
   1. Try requesting a new IP address on PC1 and PC3

      NOTE: Did you remember to configure Router1 for DHCP-Relay?

   2. View the route taken from PC1 to PC3

      > trace 10.0.2.X -P 1

      

   3. Cut the path that the ICMP packet took to test if RIP can dynamically update network paths
      

      

      > trace 10.0.2.X -P 1

      

Hopefully this exercise proved how significantly easier routing protocols are compared to manually assigning routes in networks.

End of Lab