Software Defined Networks (HY436)

In this repository you can find the assignments and my solutions of the course Software Defined Networks (HY436) during the winter semester of year 2022.

Assignment 1 (Simple Load Balancer)

Overview

In this assignment we had to implement a simple load balancer using the OpenFlow protocol. The load balancer had to be implemented using the POX controller. The topology of the network was the following:

Files Structure (from assignmen1 foler)

• assignment1.pdf: Complete assignment description.
• SimpleLoadBalancer.py: The python file of the load balancer. It contains the code of the load balancer.
• SimpleLoadBalancer_conf.json: A JSON file containing the topology description (client/server colors and IP addresses).
• mega-test.png: A screenshot of the final test run.

How to run

1. Requirements:
   • Mininet
   • POX
   • SimpleLoadBalancer.py needs to be in the /pox/ext folder.
2. Run the following commands:
   • sudo mn --topo single,8 --controller remote --mac --switch ovsk (to create the topology)
   • ./pox.py SimpleLoadBalancer --configuration_json_file=ext/SimpleLoadBalancer_conf.json (to run the load balancer) (This command needs to be run from the pox folder)

Assignment 2 (Clos topology)

Overview

In this assignment we had to implement a Clos topology for data centers using the OpenFlow protocol. The topology had to be implemented using the POX. The topology is created using the following two parameters:

• c or --core : The number of core switches.
• f or --fanout : The number of child nodes each node has.

The Clos topology has the following three layers:

• Core layer: The core layer is the top layer of the topology. It contains the c number of core switches.
• Aggregation layer: The aggregation layer is the middle layer of the topology. It contains the c*f number of aggregation switches.
• Edge layer: The edge layer is the bottom layer of the topology. It contains the c*f*f number of edge switches. Each edge switch is connected to f hosts.

The topology of a network with parametes c=1 and f=2 is the following:

Files Structure (from assignmen2 foler)

• assignment2.pdf: Complete assignment description.
• src_code/: The folder containing the requrired code.
  • CloudNetController.py: The python file containing the code of the controller.
  • clos_topo.py: The python file used to initialize the topology.
  • firewall_policies.csv: A CSV file containing the firewall policies.
  • migration_events.csv: A CSV file containing the migration events.
  • tcp_sender.py, tcp_receiver.py, udp_sender.py, udp_receiver.py:Python files used to send and receive TCP and UDP packets.

How to run

1. Requirements:
   • Mininet
   • POX
   • SimpleLoadBalancer.py needs to be in the /pox/ext folder.
2. Run the following commands:
   • sudo python clos_topo.py -c <# of core switches> -f <# of fanout> (to create the topology)
   • /pox.py openflow.discovery CloudNetController --firewall_capability=<True|False> --migration_capability=<True|False> (to run the load balancer) (This command needs to be run from the pox folder)

Assignment 3 (Simple load balancer using P4 Switch programming language)

Overview

In this assignment we had to implement the same load balancer we implemented in the first assignment using the P4 Switch programming language instead of a POX controller.

The topology of the network is the following:

Files Structure (from assignment3 foler)

• assignment3.pdf: Complete assignment description.
• src_code/: The folder containing the requrired code.
  • simple_load_balancer.p4: The P4 file containing the code of the load balancer.
  • slb-runtime.json: The JSON file containing the runtime configuration of the load balancer.
  • reconf_lb_groups_runtime.py: The python file used to reconfigure the load balancer at runtime.
  • topology.json: The JSON file containing the topology of the network.
  • send.py, recieve.py: The python files used to send and receive TCP packets.

How to run

1. Requirements:

   • Get the p4 vm image and open it in a vm tool like VirtualBox.
   • Upload the following files in a new directy in the /home/p4/tutorials/exercises folder:
     • simple_load_balancer.py
     • slb-runtime.json
     • topology.json
     • Makefile

2. Run the following commands (in the new directory with the files above):

   • make stop ; make clean (to stop and clean the last topology)
   • make run (to run the mininet and the load balancer)

Assignment 4 (Artemis Implementation)

Overview

For the fourt assignment I ran an instance of Artemis using a custom configutation file (code can be found below) to suit the assignment’s needs. In the config file there is a prefix watched (snd_assignment4) which is requested from the assignment. The source AS (sdn_assignment4_asn) and the neighbor AS (sdn_assignment4_neighbor) are also set up and a rule connecting ASes and prefixes is present too. Also a monitor is setup according to the basic config file from the git repository

Configuration File:

#
# ARTEMIS Configuration File (HY436 Assignment4)
#
# Start of Prefix Definitions
prefixes:
  sdn_assignment4: &sdn_assignment4
  - 184.164.247.0/24
# End of Prefix Definitions

# Start of ASN Definitions
asns:
  sdn_assignment4_asn: &sdn_assignment4_asn
  - 61574
  sdn_assignment4_neighbor: &sdn_assignment4_neighbor
  - 47065
# End of ASN Definitions

# Start of Monitor Definitions
monitors:
  riperis: ['']
  bgpstreamlive:
  - routeviews
  - ris
  bgpstreamkafka:
    host: bmp.bgpstream.caida.org
    port: 9092
    topic: '^openbmp\.router--.+\.peer-as--.+\.bmp_raw'
  bgpstreamhist: '/etc/artemis/'
# End of Monitor Definitions

# Start of Rule Definitions
rules:
- prefixes:
  - *sdn_assignment4
  origin_asns:
  - *sdn_assignment4_asn
  neighbors:
  - *sdn_assignment4_neighbor
  mitigation: manual
# End of Rule Definitions 

Results

In the screenshots included below are the hijacks found by Artemis. In total two types of hijacks were picked up by my implementation, E|0|-|- and E|1|-|-. E|0|-|- means that there was a hijack for the exact prefix (sdn_assignment4) with an illegal origin. E|1|-|- means that there was a hijack for the exact prefix (sdn_assignment4) with a legal origin but an illegal first hop. In the second screenshot an ongoing hijack can also be noticed!

• E|0|-|- hijacks:

• E|1|-|- hijacks: