Deutsch Intern
Chair of Computer Science III

Omnet

An OpenFlow Extension for the OMNeT++ INET Framework


Introduction

Software Defined Networking (SDN) is a new paradigm for communication networks which separates the control plane from the data plane of forwarding elements. This way, SDN constitutes a flexible architecture that allows quick and easy configuration of network devices. OpenFlow is currently the most prominent approach which implements the SDN concept and offers a high flexibility in the routing of network flows.

On this website, we present the implementation of our model of the OpenFlow system for INET-2.0 and OMNeT++ 4.2 based on the OpenFlow switch specification 1.0.

 

Motivation

OpenFlow and the first controller implementations are already deployed in networks. However, as the number and size of production networks deploying OpenFlow increases, relying on a single controller for the entire network might not be feasible for several reasons. So, there is the question what would be a better controller architecture with respect to performance, reliability, and scalability required to process new flows and program the switches.

Until now, only few performance evaluations of OpenFlow architectures exist. Testbeds are often limited to smaller topologies, but the mentioned problems of a controller especially occur on larger, geographically distributed architectures. Simulation tools are much more suitable for this task since they allow to evaluate the scalability of the chosen controller. Furthermore, they allow to validate mechanisms before their deployment. Additionally, changes in the specification of the investigated technology can easily be integrated in the simulation model.

 

Future Work

The currently implemented OpenFlow model is restricted to single controller deployments and distributed controller architectures are not possible in the current state. As future work, we plan to extend our model so that it can be used as generic framework for the simulation of more sophisticated distributed controller architectures, which use for example a hierarchical approach. Therefore, it is necessary to introduce different controller domains which partition the network. This approach further requires inter-controller communication and a master controller which manages the different domains and ensures connectivity. As a last step, also resilience should be considered, for example by introducing backup controllers.

 

Authors

Dominik Klein
Chair of Communication Networks (Informatik III)
Institute of Computer Science
University of Wuerzburg
Personal webpage

Michael Jarschel
Chair of Communication Networks (Informatik III)
Institute of Computer Science
University of Wuerzburg
Personal webpage

 

Links

The paper describing our implementation was presented at the 6th International workshop on OMNeT++ in Cannes, France and can be downloaded under the following link:

An OpenFlow Extension for the OMNeT++ INET Framework

The presentation of our model at the 6th International workshop on OMNeT++ in Cannes, France can be downloaded under:

An OpenFlow Extension for the OMNeT++ INET Framework

The current version of the OpenFlow simulation model for OMNeT++ 4.2 and INET-2.0 can be downloaded from:

Implementation at GitHub

The following links and documents represent a good starting point to OpenFlow:

  • OpenFlow webpage: link
  • Open Networking Foundation: link
  • OpenFlow Whitepaper: PDF
  • OpenFlow Specification 1.0: PDF