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This project will enable ns-3 simulations to use OpenFlow switches (McKeown et al.), widely used in research. OpenFlow switches are configurable via the OpenFlow API, and also have an MPLS extension for quality-of-service and service-level-agreement support. By extending these capabilities to ns-3 for a simulated OpenFlow switch that is both configurable and can use the MPLS extension, ns-3 simulations can accurately simulate many different switches.


  1. Develop an OpenFlowSwitchHelper class that can take an ns3::Node and install an OpenFlowSwitch NetDevice. Develop an OpenFlowSwitch NetDevice and Channel.
    1. Draw inspiration from the OpenFlowMPLS model. There exists a software switch reference implementation for running MPLS-enabled OpenFlow, created by the OpenFlowMPLS Project ( This implementation, written in C code, melds an MPLS-functional OpenFlow build (openflow-mpls.tgz) with switch-running code (openflow-mpls.tgz/switch/) that runs in the user-space.
    2. Copy the MPLS-functional OpenFlow build. It will be a hard copy, not a linked dependency. Due to the MPLS functionality, the switch-running code depends on internal functionality that isn't yet present on the most recent non-MPLS OpenFlow build. It is configured to be built by make presently, so it will also be reconfigured to be built by waf.
    3. Translate the switch-running code into the ns-3 architecture. The software switch reference implementation has several fundamental issues that must be addressed.
      1. It runs on the command line. The code that sets up the switch using the OpenFlow API is in the 'main' function of openflow-mpls.tgz/switch/switch.c. This will be copied to the StartSwitch() function in the OpenFlowSwitch class, and the parameters for the command line will become ns3::Attributes of the OpenFlowSwitch.
      2. It runs on physical ethernet devices. This will be abstracted to ns3::NetDevices. By aggregating the OpenFlowSwitch with a Node, different NetDevices can be installed to simulate a PointToPoint, Wifi, et cetera receiving/sending adapters for the OpenFlowSwitch.
      3. It runs without maintaining a simulation clock. The ns3 simulation clock API will be used to synchronize the OpenFlowSwitch.
      4. It runs without ns-3 configurable parameters. These will be parameterized, variables will be added to the OpenFlowMPLS classes and structs, each linked to a specific ns3::Attribute.
      5. It runs, as expected, with different packet structs that aren't immediately compatible with ns3::Packets. Wrappers for converting between these classes will be developed for the OpenFlowSwitch class.
  2. To demonstrate this project's results are in working condition, I will endeavor to create an ns-3 simulation that demonstrates MPLS being used in a small topology. It should use code similar to:
Ptr<Node> switch = CreateObject<Node>();
OpenFlowSwitchHelper of;
// set other attributes


I have set up a Google Project (at This stub will be updated with the latest patch files, described below.

File/Directory Details src/routing/openflowswitch/ class OpenFlowSwitch extends ns3::Object; It accesses and provides an ns-3 layer to the OpenFlowMPLS code to convert ns-3 packets through the receiving and forwarding process. src/helper/ class OpenFlowSwitchHelper; Aggregates the OpenFlowSwitch Object with a provided ns3::Node to associate it as an OpenFlow switch. src/routing/openflowswitch/openflow/ Directory containing all the OpenFlowMPLS code. The files not in the /switch directory do not need to be edited for this project, so I will not include them in this list of patch files, though they will be provided in every download, because the specific switch code depends on it. switch/ It holds all the specific code for the MPLS-enabled OpenFlow switch. This code needs to be reviewed line-by-line in the parameterization process. chain.c, chain.h Chains tables (defined in table.h and implemented in table-hash.c and table-linear.c) together to make a trie, thereby simulating a hardware TCAM, which is the basis of OpenFlow development. crc32.c, crc32.h datapath.c, datapath.h dp_act.c, dp_act.h er_act.c, er_act.h nx_act.c, nx_act.h pt_act.c, pt_act.h switch.c switch-flow.c, switch-flow.h switch-port.c, switch-port.h table.h table-hash.c table-linear.c


I will upload the latest build of the patch to the Google Project on a consistent basis. With regard to the expected time of development, I shall start by uploading it monthly. Later on in the project timeframe, probably August, I will upload more frequently to apply smaller changes.

The last three days of each time estimate will be spent testing and verifying the code. Time estimates based on the Approach chart:

  1. One week to complete the OpenFlowSwitchHelper class. OpenFlowSwitchHelper's functionality is relatively simple, and will probably be similar to other routers' Helper classes.
  2. One to two weeks to complete the shell of the OpenFlowSwitch class. At this point, testing and verifying will be implemented. It may include adding a small store-and-forward process to the OpenFlowSwitch and making a small demo to make sure it can be used when ns-3 is built.
  3. Two to four weeks to complete the OpenFlow integration.
    1. One to two weeks to integrate the OpenFlowMPLS code into the switch without yet parameterizing it. At this point testing and verifying will be on a fully capable OpenFlow switch, so a network topology demonstration will be created with analysis on the results. There probably won't be too much output in the results because of the lack of parameters.
    2. One to two weeks to parameterize the OpenFlowMPLS code. The same demonstration developed for stage 2 should return more detailed results in the testing and verifying process, and should predictably change as different parameters are modified.
  4. One week to finalize the demonstration (it will already be partially constructed as of stage 2).
  5. Remaining time spent on testing, verifying, and polishing the code and adding documentation.


Kohler, E., Morris, R., Chen, B., Jannotti, J., and Kaashoek, M. F. 2000. The click modular router. ACM Trans. Comput. Syst. 18, 3 (Aug. 2000), 263-297. DOI=

Kurkowski, S., Camp, T., and Colagrosso, M. 2005. MANET simulation studies: the incredibles. SIGMOBILE Mob. Comput. Commun. Rev. 9, 4 (Oct. 2005), 50-61. DOI=

McKeown, N., Anderson, T., Balakrishnan, H., Parulkar, G., Peterson, L., Rexford, J., Shenker, S., and Turner, J. 2008. OpenFlow: enabling innovation in campus networks. SIGCOMM Comput. Commun. Rev. 38, 2 (Mar. 2008), 69-74. DOI=

Neufeld, M., Jain, A., and Grunwald, D. 2002. Nsclick:: bridging network simulation and deployment. In Proceedings of the 5th ACM international Workshop on Modeling Analysis and Simulation of Wireless and Mobile Systems (Atlanta, Georgia, USA, September 28 - 28, 2002). MSWiM '02. ACM, New York, NY, 74-81. DOI=

About Me

I've been a programmer for the past six years, and I received my B.S. in Computer Science from West Chester University in Spring 2009. I've always been interested in research, and now as a newly accepted Temple University PhD student (starting Fall 2010), I want to pursue the Networking field within research. An ns-3 project in GSoC 2010 presents this perfect opportunity: I can enter my PhD career as someone who is already furthering academia.

I have been programming in C++ and Python for the past six years. As for ns-3 experience, I've been working with ns-3 for the past two months, since I first saw the opportunity for Networking research through GSoC by working with ns-3.

This is my first attempt at adding to an open source project.


I did a Natural Language Processing (NLP) research project in my senior year at West Chester University. I programmed in Python, and experimented with using the Natural Language Toolkit (NLTK) to parse text into flash cards, an automatic SparkNotes for studying purposes.

Personal Interests

I have a variety of interests within Computer Science research. I'm interested in AI, specifically as it applies to Natural Language Processing (NLP), and how NLP could be used to automatically generate supplementary studying and testing material for students. I'm also interested in cloud computing as a method for dividing-and-conquering all sorts of research problems. But most importantly, I am interested in Networking research, which I will able to fully pursue at Temple University. Because I am focusing my research on Networking, I want to pursue a GSoC 2010 project that will teach me more about Networking and make me better known to the Networking academic community.