Senior Network Security Engineer

NorthMark Compute & Cloud; Dallas (TX); On-site; USD 120,000 - 180,000; Full time

Job summary

NorthMark Compute & Cloud in Texas is seeking a hands-on Network Security Engineer to design and maintain the security infrastructure that supports our HPC and cloud environment. You will build controls, automation, and operational practices to scale protection and resilience while balancing speed and reliability.

In this role you will work with peers and leadership to implement secure network architectures, guide security decisions, and mentor junior engineers to strengthen our security posture

Qualifications

• 7+ years of experience in network security engineering.
• Strong understanding of OSI model and TCP/UDP protocols.
• Experience with on-premises and cloud networks (AWS, Azure, or GCP).
• Familiarity with security frameworks and baseline hardening.

Responsibilities

• Design, implement, and maintain scalable network security architecture.
• Lead security controls such as firewalls, IDS/IPS, and VPNs.
• Collaborate with cross-functional teams across IT operations.
• Develop and update network security standards and documentation.
• Mentor junior engineers and contribute to security governance.
• Participate in security reviews for new projects and third-party integrations.

Skills

Network security engineering

OSI model & protocols

Security architecture

Automation opportunities

Security monitoring

Strong communicator

Tools

Firewalls

IDS/IPS

VPNs

SIEM

Cloud platforms (AWS/Azure/GCP)

VxLAN EVPN

Job description

The Company

NorthMark Compute & Cloud (NMC²) is backed by dedicated leadership and investment, with a clear mission as it operates at the bleeding edge of technology. Its goal is to scale and enhance the high-performance computing (HPC) and cloud infrastructure that supports its clients’ research, production, and delivery, enabling breakthroughs that shape the industries of tomorrow. Its engineers build critical infrastructure to eliminate friction in scientific research, simulations, analysis, and decision-making, accelerating discovery and driving faster innovation.

The Position

The Network Security Engineer is a hands-on technical role within NMC²’s centralized Security Engineering organization, responsible for designing and maintaining the network security infrastructure that protects our hyperscale HPC and cloud compute environment. This role plays a direct part in building the controls, automation, and operational practices that keep NMC²’s infrastructure secure at scale.

You would contribute to the design, development, and delivery of critical network security components within complex, enterprise-scale systems and projects. This role brings strong technical depth in network security architecture and controls, applying sound judgment to resolve complex problems and balance technical integrity with delivery speed. Working closely with the Manager of Network and Infrastructure Security and cross-functional peers, the Senior Security Engineer drives meaningful improvements to the organization\u2019s security posture while serving as a subject matter expert and mentor within the team.

Responsibilities

• Contribute to the design, implementation, and delivery of scalable network security architecture and controls including firewalls, IDS/IPS, and VPNs across on-premises and cloud environments Serve as the team\'s primary subject matter expert for network security technologies, providing guidance and technical direction on complex security challenges


• Apply technical depth and sound judgment to resolve complex network security challenges, making trade-offs that balance security requirements with operational and delivery needs


• Collaborate effectively with cross-functional peers across infrastructure, cloud, and IT operations, communicating technical decisions and progress with clarity and ensuring alignment across teams


• Develop and maintain network security standards, policies, and technical documentation


• Support network segmentation and micro-segmentation efforts by providing technical expertise on traffic flows, access controls, and policy enforcement


• Participate in security architecture reviews for new projects, systems, and third-party integrations to ensure network security requirements are addressed


• Mentor junior security engineers and contribute to the overall growth and development of the network security team

Requirements

• 7+ years of experience in network security engineering, with hands-on experience across trusted, untrusted, and DMZ environments


• Strong understanding of network protocols and the OSI model, with practical experience in TCP/UDP-based applications, routing, switching, and load balancing


• Experience securing both on-premises and cloud network environments (AWS, Azure, or GCP)


• Experience designing and securing network environments across both on-premises and cloud platforms (AWS, Azure, or GCP)


• Proven ability to identify and deliver process improvements, automation opportunities, and tool enhancements within a security engineering function


• Experience with security monitoring tools and SIEM platforms, with the ability to investigate and respond to network-based threats


• Strong understanding of security frameworks and hardening standards such as NIST, CIS Benchmarks, or ISO 27001


• Effective communicator with the ability to articulate technical decisions and trade-offs clearly to both technical peers and leadership

Preferred

• Relevant certifications preferred, such as CCNP Security, PCNSE, CISSP, or equivalent


• Experience with VxLAN EVPN data center architecture


• Background in SOC operations or working with MSSPs


• Firewall automation experience