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CWD Tools for Improving Cyber Simulations

Download the open source software tools that the SEI developed to create realistic cyber simulations or access information to learn more about each one.


Software Engineering Institute


The SEI develops open source software tools to create secure and realistic cyber simulations. This collection makes these tools available for download and groups the software with supporting materials that describe the benefits an organization can gain from using them. Some of these features and benefits include a realistic simulated Internet, realistic network traffic, and convincing and lifelike behavior of host systems. These tools can help organizations save time and money in the development and deployment of training exercises, and participants will be more engaged in cyber exercises thanks to the heightened realism that the tools deliver. Because these tools recreate the real world and make training exercises more realistic, exercise participants can gain experience that will help them reach elite levels of performance.

Collection Contents

  • GHOSTS Software and Supporting Materials

    January 31, 2019 Collection

    GHOSTS is a non-player character (NPC) orchestration generator developed by the SEI to create realistic NPCs and network traffic for cyber-training simulations. Download the tool or read more about it in this collection.

  • vTunnel Software and Supporting Materials

    October 1, 2018 Collection

    vTunnel is a software tool developed by the SEI that hides certain network activity—such as command and control traffic—from participants in cyber-training exercises. Download the tool or read more about it in this collection.

  • TopoMojo Software and Supporting Materials

    December 1, 2018 Collection

    TopoMojo is an open source tool developed by the SEI that contains both a lab builder and player so that lab creators can build, share, and deploy labs quickly. Read more about TopoMojo in this collection, or download the tool.

  • TopGen Software and Supporting Materials

    November 1, 2017 Collection

    TopGen is a virtualized service simulator that provides a simulation of the Internet for offline exercise and training networks. This collection provides access to the tool and more information about it.

  • WELLE-D Software and Supporting Materials

    November 1, 2018 Collection

    WELLE-D is a virtual wireless networking environment for hosting realistic training where participants can develop wireless security skills in a cost-effective and controlled way. Download the tool or learn more about it in this collection.

  • GreyBox Software and Supporting Materials

    November 1, 2017 Collection

    GreyBox is a software tool that gives cyber-exercise participants the perception that they are connected to the real Internet in disconnected training environments. Learn more about GreyBox or download it in this collection.

  • Foundry Software and Supporting Materials

    February 28, 2019 Collection

    Foundry is a training asset management portal that functions as a hub for training content to help you optimize your use of training assets. In this collection, you can download Foundry or access documentation to learn more about it.

  • Crucible Software and Supporting Materials

    April 1, 2020 Collection

    Crucible is a powerful, open source, cyber-simulation framework that delivers cost-effective, scalable, and dynamic virtual environments. Download Crucible or learn more about it in this collection.