Chapter 1: Introduction

This tutorial presents some of the basic ideas being software-defined networking (SDN) programming with OpenFlow and Frenetic. It is divided into two sections:

• Ox: The first few chapters introduce the nuts and bolts of programming a SDN switches using Ox, a simple platform for writing OpenFlow controllers in OCaml. Apart from a few constructs for managing socket connections and message serialization, Ox gives the programmer direct access to the OpenFlow protocol. Ox is inspired by platforms such as POX and NOX, so the techniques you learn in this tutorial are applicable to those platforms too.

[Repeater with Ox] [Firewall with Ox] [Traffic Monitoring with Ox] [Learning Switch with Ox] [Network Address Translation with Ox] [Shortest Path Forwarding with Ox]

• Frenetic: The following chapters teach you how to program SDNs using the NetKAT domain-specific programming language. NetKAT provides high-level abstractions and rich, compositional features that greatly simplifies SDN programming.

[NetKAT Repeater] [Firewall with NetKAT] [Routing with NetKAT] [NetKAT Manual] [Conclusion]

Software Environment

This is a hands-on tutorial with several programming exercises. We recommend using the virtual machine we’ve prepared that has all the necessary software that you need pre-installed. To run this, you need the following open source software package applicable for your host computer:

• VirtualBox

The Frenetic Tutorial VM runs Ubuntu 16.04 as the guest OS. It has OCaml, OPAM, Mininet, Wireshark, and Frenetic itself pre-installed. The standard VIM, Emacs, and Nano editor packages are installed, but you can install your own through the normal Ubuntu package mechanisms.

The Frenetic tutorial VM is stored on Amazon Web Services S3 cloud storage, and installing it requires very little effort. First, launch the VirtualBox GUI on your Windows, Linux, or Mac OS host PC. Then:

• Download the Frenetic tutorial VM OVA (Open Virtualization Appliance) located here.
• Navigate the menus to File > Import Appliance.... This will open a modal dialog instructing you to import the appliance.
• Enter the path to the downloaded OVA file, or browse your file manager to locate it.
• Select Next.
• Select Import. This imports the OVA file into VirtualBox, and the Frenetic VM should now appear in your VirtualBox GUI.
• Lastly, double click the VM in the VirtualBox GUI to launch the Frenetic tutorial VM.

References

• Real World OCaml

  To write Ox and NetKAT programs, it will be useful to be familiar with the OCaml language. Chapters 1–8 and 18 should cover the necessary background material.

• OpenFlow 1.0 Specification

  This specification describes OpenFlow switches and configuration protocol in detail. You’ll find that most of the Ox Platform Reference simply reflects the OpenFlow messages and data types into OCaml.

• Mininet

  This webpage describes Mininet, a system we will use to run controllers on a simulated network of switches.

• Frenetic OCaml APIs

  This web page provides documentation for the Ox and NetKAT libraries, as well as other supporting libraries used in this tutorial.