Senior Network Engineer

Sim Space serves as an AI Proving Ground where organizations can confidently train, test, and outmaneuver adversaries in any environment. Trusted by allied governments, militaries, enterprises, and research institutions worldwide, Sim Space enables adaptive, AI-ready defenses that stay ahead of evolving threats. Founded in 2015 by experts from U.S. Cyber Command and MIT Lincoln Laboratory, the platform unifies training, testing, and validation in a realistic, live-fire simulation-that helps teams evaluate security investments, optimize performance, and compress cyber readiness cycles from months to days.

We are an organization that is focused on building our culture and mindfully enhancing our atmosphere every day which is why we have collaborated on an integral value system. Our governing philosophy of being Human Centered is deeply embedded within our value system. We apply this philosophy to every one of our internal team members, external clients, and their customers.

We believe that people are at the center of everything we do. Sim Space fosters a culture of continuous learning, curiosity, and professional growth. That belief shows up in action: in-house training, internal and external learning platforms, cyber conferences, industry events, and dedicated time for skill development. Our people are empowered to shape their careers - and it shows. Year over year, Sim Space consistently outperforms industry benchmarks in internal mobility, promotions, and total rewards growth.

We are a team of innovators, protectors, and problem-solvers. We believe diversity of thought and experience fuels better solutions, and we’re committed to building teams that reflect the communities we serve. Whether you’re remote or office-based, you’ll collaborate with talented colleagues across departments and time zones, united by the mission to create a safer digital world.

The Senior Network Engineer position is a senior technology practitioner responsible for the collaborative design, implementation, monitoring, maintenance, and security of enterprise network infrastructure across Sim Space corporate offices and data centers across the United States and Europe.

This individual will serve as a senior technical resource and subject matter expert for both core network and network security infrastructure, helping lead operational support, architecture, modernization, and incident response efforts. The role combines traditional network engineering responsibilities with expanded ownership of network security operations, secure access technologies, firewall management, web application protection, and vulnerability management.

The successful candidate will possess deep technical expertise in enterprise networking and security technologies, strong analytical and troubleshooting skills, and the ability to lead initiatives and mentor junior engineers. Effective collaboration with infrastructure, cloud, security, and business stakeholders is critical to success in this role.

• Act as the subject matter expert for Sim Space network and network security infrastructure
• Design, implement, support, and secure enterprise network infrastructure and software-defined networking solutions
• Configure and maintain complex VMware environments leveraging NSX-T, DVS, and software-defined networking technologies
• Contribute to the design and implementation of resilient, secure, and scalable network architectures
• Configure and troubleshoot virtual networking, VLANs, VRFs, traffic forwarding, and hybrid cloud connectivity
• Lead network modernization initiatives, including technology refreshes, architecture improvements and capacity planning
• Troubleshoot all levels of network connectivity issues including, but not limited to, network outages, switch failures, network performance, network interface card (NIC), cabling, TCP/IP configuration, etc.
• Perform troubleshooting of complex network and security incidents, including outages, performance issues, routing failures, VPN issues, and other network…