The document presents an overview of open source software-defined networking (SDN) controllers, highlighting their significance and potential for innovation within the networking space. It details various open source SDN controllers, their features, and development environments, emphasizing community contributions and accessibility. The content reflects on the benefits of separating the control and forwarding planes, as well as the evolution of several SDN controller projects.

1. 최영락 (Ian Choi)
Manager / NAIM Networks
ian@naimnetworks.com
Mar 27, 2014

2. Copyright ⓒ 2014 by NAIM Networks, Inc. All rights reserved. 2
Table of Contents
Open Source & SDN Controllers
Open Source SDN Controllers – C & Python
Open Source SDN Controllers – Java
Comments on SDN Controllers
I
II
III
IV

4. Copyright ⓒ 2014 by NAIM Networks, Inc. All rights reserved.
I. Open Source Environment
4
SDN Controllers
SDN Related Open Sources
Enabling Specification / Organizations

5. Copyright ⓒ 2014 by NAIM Networks, Inc. All rights reserved.
I. Why Open Source with Community?
5
Open Source At A Glance
! 600,000+ projects
! 100+ Billion lines of code
! 10 Million person-years of work
SDN innovation will come from
open source like
! 40% of cloud innovation
! 15% of mobile enterprises
! 19% of mobile apps
v Free software tools and platforms accessible to all
v Support from passionate SDN experts
v Freedom to use, redistribute and modify without IP infringement
Empowered
community and
continuous
improvement
Huge creative and
diverse potential for
unprecedented scale
Src.: ON.LAB

6. Copyright ⓒ 2014 by NAIM Networks, Inc. All rights reserved.
I. Unlocking Network Potential
6
Traditional Networking
! Control plane
embedded into the box
! Closed proprietary
with no open interface
! A big barrier to
innovation
The Promise of SDN
! Separation of forwarding
and control planes
! Open and vendor
agnostic interface (e.g.
OpenFlow)
! Well defined control
plane abstractions to
enable rapid innovation
Need to create
new tools
Use them and
modify them freely
to experiment new
possibilities
Exchange ideas
and experience
Src.: ON.LAB

7. Copyright ⓒ 2014 by NAIM Networks, Inc. All rights reserved.
I. SDN Controller Overview – (1)
v Applications for Network Devices
7
Network Device
Software
ASIC
TCAM
TCAM
TCAM
TCAM
TCAM
Low-Level ASIC Interface
TCAM
TCAM
Operating System (OS)
App
App
App
App
App
App

8. Copyright ⓒ 2014 by NAIM Networks, Inc. All rights reserved.
I. SDN Controller Overview – (2)
v Separation of Applications
8
Controller (Openflow Controller / SDN Controller)
Network Device
Software
ASIC
TCA
M
TCA
M
TCA
M
TCA
M
TCA
M
Low-Level ASIC Interface
TCA
M
TCA
M
Operating System (OS)
App
App
App
App
App
App
Network Device
Software
ASIC
TCA
M
TCA
M
TCA
M
TCA
M
TCA
M
Low-Level ASIC Interface
TCA
M
TCA
M
Operating System (OS)
App
App
App
App
App
App
Network Device
Software
ASIC
TCA
M
TCA
M
TCA
M
TCA
M
TCA
M
Low-Level ASIC Interface
TCA
M
TCA
M
Operating System (OS)
App
App
App
App
App
App
App
App
App
App
App
App
Operating System (OS)

9. Copyright ⓒ 2014 by NAIM Networks, Inc. All rights reserved.
I. SDN Controller Overview – (3)
v The All-Seeing Eye for Almighty
9
Network Device
Software
ASIC
TCAM
TCAM
TCAM
TCAM
TCAM
Low-Level ASIC Interface
TCAM
TCAM
SDN Controller
Network Device
Software
ASIC
TCAM
TCAM
TCAM
TCAM
TCAM
Low-Level ASIC Interface
TCAM
TCAM
Network Device
Software
ASIC
TCAM
TCAM
TCAM
TCAM
TCAM
Low-Level ASIC Interface
TCAM
TCAM
Flow
Flow
Flow
App
App
App
App
App
App
Operating

10. System

11. (OS)

12.
Southbound
• OpenFlow
• NetConf
• SNMP
• Node Aware
Northbound
• Code Base Automation
• Controls vBRAS, vCDN, vADC
Northbound
Southbound
Agent
Agent
Agent

13. Copyright ⓒ 2014 by NAIM Networks, Inc. All rights reserved.
I. Open Source + SDN Controllers
10
Vendors’ perspective
Source : HP Technical white paper
Need to create
new tools
Use them and
modify them freely
to experiment new
possibilities
Exchange ideas
and experience
Open sources’ perspective
v API is an important part to compose SDN
architecture with controllers and elements.

14. Copyright ⓒ 2014 by NAIM Networks, Inc. All rights reserved.
I. Open Source SDN Controllers
v Many Open Source SDN controllers!
11
SDN Controller
Project Organization(s) Memo
Beacon
Stanford
University
Beacon is a fast, cross-platform, modular, Java-based controller that supports both event-based and threaded
operation.
FloodLight
Big Switch
Networks
The Floodlight controller is an enterprise-class, Apache-licensed, Java-based OpenFlow Controller. It was
forked from the Beacon controller, originally developed by David Erickson, and now is supported by a
community of developers including a…
FlowER
Travelping
GmbH
FlowER is an open-source Erlang based OpenFlow controller. Its purpose is to provide a simplified platform for
writing network control software in Erlang. Its still under development but Travelping, FlowER’s creator, is
already using it in its…
OpenIRIS
ETRI
(Korea)
OpenIRIS (pronounced ai-ri-s) is the open source version of IRIS, a recursive SDN OpenFlow Controller
created by IRIS Research Team in ETRI, Korea.
Jaxon
University
of Tsukuba
Jaxon is a Java-based OpenFlow Controller that provides a thin interface to NOX to bridge Java applications
and the NOX controller.
Mul SDN
Controller
Kulcloud
(Korea)
MūL, is an OpenFlow (SDN) controller. It has a C based multi-threaded infrastructure at its core. It supports a
multi-level north bound interface for hooking up applications.
NOX ICSI
NOX was the first OpenFlow controller. It has been the basis for many and various research projects in the
early exploration of the SDN space.
OpenContrail
Juniper
Networks
OpenContrail is an Apache 2.0-licensed project that is built using standards-based protocols and provides all
the necessary components for network virtualization–SDN controller, virtual router, analytics engine, and
published northbound APIs.
OpenDaylight
Linux
Foundation
The adoption of new technologies and pursuit of programmable networks has the potential to significantly
improve levels of functionality, flexibility and adaptability of mainstream datacenter architectures. To leverage
this abstraction to its fullest
POX ICSI
POX is a Python-only version of NOX that provides controller functionality within a rapid prototyping
environment.
Ryu Network
Operation system
NTT
Communications
Ryu is a network OS that integrates with OpenStack and supports OpenFlow. It provides a logically centralized
controller and well-defined API that make it easy for operators to create new network management and
control applications.
Trema NEC An Open Source modular framework for developing OpenFlow controllers in Ruby/C.
…

15. Copyright ⓒ 2014 by NAIM Networks, Inc. All rights reserved.
[Java]

16.
[Python]

17.
[C/C++]

18.
I. Pedigree Chart
12
Controller
(Proprietary)
Big Network
Controller
(Proprietary)

19.
OPEN
DAYLIGHT

20.
(nox-classic nox)

21.
(Proprietary)

23. 1. NOX
2. POX
3. Ryu
4. MUL

24. Copyright ⓒ 2014 by NAIM Networks, Inc. All rights reserved.
II-1. NOX – (1)
v Two Versions of NOX
! NOX-classic
• Original NOX (now, officially deprecated)
– https://github.com/noxrepo/nox-classic
• C++-based SDN controller, but applications can be
developed using Python
• Provides graphical user interfaces
! NOX
• Separated from NOX-classic in 2012
– https://github.com/noxrepo/nox
• Only supports C++ for application development
• Fewer default applications than NOX-classic
– But, much faster and has a much cleaner source base
• No graphical user interfaces
14

25. Copyright ⓒ 2014 by NAIM Networks, Inc. All rights reserved.
II-1. NOX – (2)
v Original NOX (a.k.a., nox-classic)
! Multi-thread C++-based controller
! GNU GPL v3 license
! Written on top of Boost library
• Provides fast, asynchronous IO (Boost.Asio)
! Supported target system: Linux
! SDN applications can be developed with Python
! Documentation: doxygen, # of tutorials
15
Sample application written in C++
Sample application written in C++ and Python using SWIG library
Sample application written in Python
SWIG (Simplified Wrapper and Interface Generator): an open source software tool used to connect computer programs or libraries written in
C or C++ with scripting languages such as Lua, Perl, PHP, Python, …

26. Copyright ⓒ 2014 by NAIM Networks, Inc. All rights reserved.
II-1. NOX – (3)
v Original NOX (a.k.a., nox-classic)
! Example: Switch application (C++, partial)
16

27. Copyright ⓒ 2014 by NAIM Networks, Inc. All rights reserved.
II-1. NOX – (4)
v Original NOX (a.k.a., nox-classic)
! Example: Switch application (Python, partial)
17

28. Copyright ⓒ 2014 by NAIM Networks, Inc. All rights reserved.
II-1. NOX – (5)
v Original NOX (a.k.a., nox-classic)
! Graphical user interfaces
18

29. Copyright ⓒ 2014 by NAIM Networks, Inc. All rights reserved.
II-1. NOX – (6)
19
v NOX (not nox-classic)
! Enhanced performance and better source
readability/maintenance structure
! Less active open source community than POX
• Only 28 source commits for the recent 2 years
! Documentation: poor (only doxigen)

30. Copyright ⓒ 2014 by NAIM Networks, Inc. All rights reserved.
II-1. NOX – (7)
20
v NOX (not nox-classic)
! Example: Switch application (C++, partial)
The use of Boost library
(cf. nox-classic: libc++)
The same structure as nox-classic
python code
(better readability)

31. Copyright ⓒ 2014 by NAIM Networks, Inc. All rights reserved.
II-2. POX – (1)
v Overview
! A platform for rapid development and
prototyping of network control using Python
! Supports all the targets (Linux, Mac, Windows)
! Still active (# of commits, forum in noxrepo.org)
! Documentation; Wiki, comments on source files
21
Src.: noxrepo.org/pox (NOX-Python: pypy)

32. Copyright ⓒ 2014 by NAIM Networks, Inc. All rights reserved.
II-2. POX – (2)
v Example
! pox/forwarding/l2_learning.py
22

33. Copyright ⓒ 2014 by NAIM Networks, Inc. All rights reserved.
II-2. POX – (3)
v User interfaces (needs poxdesk)
! https://github.com/MurphyMc/poxdesk/
23

34. Copyright ⓒ 2014 by NAIM Networks, Inc. All rights reserved.
II-3. Ryu – (1)
v Overview
! Completely written in Python
! Apache 2.0 License
! Supports various OpenFlow versions
• 1.0, 1.2, 1.3, 1.4
! No official graphical user interfaces
• Provided by another repo from Yamada Hideki
! Documentation
• Official Wiki: https://github.com/osrg/ryu/wiki
• Some presentations a book (English Japanese)
! Active maintenance
! Some sample apps
24

35. Copyright ⓒ 2014 by NAIM Networks, Inc. All rights reserved.
II-3. Ryu – (2)
v Example
! ryu/ryu/app/simple_switch.py (Python, partial)
25
simple_switch_13.py

36. Copyright ⓒ 2014 by NAIM Networks, Inc. All rights reserved.
II-4. MUL – (1)
v Overview – (1)
! Multi-threaded C code using pthread libevent
! GNU GPL v2 license
! Supported target system: Linux
! No official graphical user interfaces
! Documentation: Wiki Blog
• Wiki: http://sourceforge.net/p/mul/wiki/Home/
• Blog: http://kulcloud.wordpress.com/
– (Korean: kulcloudkr.wordpress.com)
! (Relatively) a few default applications
• Cli, fabric, l2switch
26

37. Copyright ⓒ 2014 by NAIM Networks, Inc. All rights reserved.
II-4. MUL – (2)
v Overview – (2)
! Less # of commits
• Total 77 commits (last: Dec 24, 2013)
! Some global interests
• Described in global homepages
– http://www.sdncentral.com/projects/mul-sdn-controller/
• Referenced on several international papers
– E.g., A. Shalimov et al, “Advanced study of SDN/OpenFlow
controllers”, CCC-SECR’ 13, 2013.
27

38. Copyright ⓒ 2014 by NAIM Networks, Inc. All rights reserved.
II-4. MUL – (3)
v Example
! application/l2switch/l2switch.c (C, partial)
28

39. Copyright ⓒ 2014 by NAIM Networks, Inc. All rights reserved.
II-4. MUL – (4)
v Execution
29
(terminal)
(OpenvSwitch)

40. 1. Beacon
2. Floodlight
3. OpenIRIS
4. Opendaylight

41. Copyright ⓒ 2014 by NAIM Networks, Inc. All rights reserved.
III-1. Beacon – (1)
v Overview
! Java-based OpenFlow controller using java.nio
(channels buffers)
! Supports OpenFlow 1.0
! BSD License (as of version 1.0.4)
• Previously: GNU GPL v2 license with Stanford University
FOSS License Exception v1.0
! Java projects can be open using Eclipse
! Following good software design patterns using
Spring Framework OSGi
! Provides web-based user interfaces
! Good Documentation: tutorial, video wiki
! (Relatively) a few default applications
• Hub, learningswitch, routing, topology (discovery)
31

42. Copyright ⓒ 2014 by NAIM Networks, Inc. All rights reserved.
III-1. Beacon – (2)
v Example
! net.beaconcontroller.learningswitch (Java, partial)
32

43. Copyright ⓒ 2014 by NAIM Networks, Inc. All rights reserved.
III-1. Beacon – (3)
v Development environment using Eclipse
33

44. Copyright ⓒ 2014 by NAIM Networks, Inc. All rights reserved.
III-1. Beacon – (4)
v Web-based user interfaces
34

45. Copyright ⓒ 2014 by NAIM Networks, Inc. All rights reserved.
III-2. Floodlight – (1)
v Overview
! Java-based Open Source OpenFlow controller
made by Big Switch Networks
! Supports OpenFlow 1.0
! Apache License
! Using Netty for network IO (ChannelBuffer, but
processes with a single thread)
! Java projects can be open using Eclipse
! Build environment: Apache ant
! Provides web-based user interfaces
! Well Documented: tutorial, javadoc, …
! Has active community, but no major version up
currently
35

46. Copyright ⓒ 2014 by NAIM Networks, Inc. All rights reserved.
III-2. Floodlight – (2)
v Example
! Main.java.net.floodlightcontroller.learningswitch
(Java, partial)
36

47. Copyright ⓒ 2014 by NAIM Networks, Inc. All rights reserved.
III-2. Floodlight – (3)
v Web-based user interfaces
37

48. Copyright ⓒ 2014 by NAIM Networks, Inc. All rights reserved.
III-3. OpenIRIS – (1)
v Overview
! Java-based Open Source OpenFlow
controller made by ETRI, Korea
! Supports OpenFlow 1.0 1.3
! Apache License
! Using Java.nio (channels buffers) with Thread
programming model
! Java projects can be open using Eclipse
! Build environment: Apache ant
! Provides web-based user interfaces
! Controller DB can be stored to Database (MongoDB)
! Good Documentation in English: tutorial, javadoc, …
38
Src.: bjlee72, ETRI

49. Copyright ⓒ 2014 by NAIM Networks, Inc. All rights reserved.
III-3. OpenIRIS – (2)
v Example
! etri.sdn.controller.app.basic.BasicOFController
(Java, Partial)
39

50. Copyright ⓒ 2014 by NAIM Networks, Inc. All rights reserved.
III-3. OpenIRIS – (3)
v Web-based user interfaces
40