OpenFlow%20Tutorial

1
OpenFlow Tutorial

• Theophilus Benson

2
Outline

• Components in an OpenFlow testbed
• Setting up a testbed
• Writing a new component
• C components version
• Python components version

3
OpenFlow Components

• Controller
• Openflow switches
• Traffic generators

OpenFlow Enabled Switches
End host1
End host3
End host2
OpenFlow Controller
4
Virtual Testbed

• Directions available online
• http//noxrepo.org/manual/using.htmlsetting-up-a-
  noxnetwork
• Requirements
• Linux system
• Qemu
• Python
• Nox code
• Other linux libraries

5
Testbed Setup

• Compile Nox code
• Set up virtual machines
• Connect topology
• Start controller
• Use appropriate components
• Connect switches to controller

6
Writing Components

• Two languages c and python
• More information found http//noxrepo.org/manual/
  app.html
• Components are stored in src/nox/apps
• Separate each component into a distinct directory
• Component Structure
• You must inherit from class Component
• You must include a call to the
  REGISTER_COMPONENT macro
• You must include the following methods
• Void configure(const Configuration )
• Void install()

7
Component Paradigm

• Register for events and specify handlers
• register_handlerlteventtypegt(boostbind(handling_m
  ethod, this, _1))
• register_handlerltPacket_in_eventgt(boostbind(Hub
  handler, this, _1))
• All work done in handler
• Return either CONTINUE or END
• NOTE you can start the controller with a list of
  components, event get passed from one to the
  other
• Returning CONTINUE means the next component
  handles the packet
• Returning END means no other components handle
  the packets

8
Demo

• Run component in openflow controller
• Ping from endhost A
• Should observe printouts in controllers console

9
Resources

• Nox website
• http//noxrepo.org
• OpenFlow Site
• http//www.openflowswitch.org/wp/documents

10
Questions