SC Cleared Network Security Engineer

X4 Technology; United States; Remote; GBP 85,000 - 110,000; Full time

Job summary

X4 Technology is seeking a SC Cleared Network Security Engineer to take technical ownership of enterprise security infrastructure in a fully remote role. You will lead design, implementation and ongoing optimisation of critical security platforms across complex networks.

You will act as the senior authority for firewall, VPN and secure access, produce high level and low level designs, and coordinate with vendors to resolve incidents while supporting data center network projects.

Qualifications

• Experience designing and supporting enterprise security solutions for large environments.
• Hands-on with Palo Alto, Zscaler and F5 technologies.
• Ability to produce HLDs/LLDs and technical documentation.

Responsibilities

• Provide technical ownership of the customer’s enterprise security infrastructure, ensuring stability, performance, and lifecycle management of critical security platforms.
• Act as the senior technical authority for firewall, network security and secure access changes, delivering design, implementation and ongoing optimisation across complex enterprise environments.
• Produce and maintain High Level Designs (HLDs), Low Level Designs (LLDs), technical documentation and operational procedures for security solutions and network infrastructure.
• Lead the investigation and resolution of complex security incidents, acting as the technical escalation point and coordinating with vendors to restore service and minimise business impact.
• Support the delivery of data center network projects by providing technical assurance, change management, hardware/software lifecycle planning and infrastructure best practice.

Skills

Firewall engineering

VPN expertise

Tools

Palo Alto

Zscaler

F5

Job description

Job Title: SC Cleared Network Security Engineer

Location: Fully Remote

SC Cleared Network Security Engineer - Role & Responsibilities

• Provide technical ownership of the customer's enterprise security infrastructure, ensuring the stability, performance, and lifecycle management of critical security platforms.
• Act as the senior technical authority for all firewall, network security and secure access changes, delivering design, implementation and ongoing optimisation across complex enterprise environments.
• Produce and maintain High Level Designs (HLDs), Low Level Designs (LLDs), technical documentation and operational procedures for security solutions and network infrastructure.
• Lead the investigation and resolution of complex security incidents, acting as the technical escalation point and coordinating with vendors to restore service and minimise business impact.
• Support the delivery of data center network projects by providing technical assurance, change management, hardware/software lifecycle planning and infrastructure best practice.

SC Cleared Network Security Engineer - Required Experience

• Proven hands-on experience designing, implementing and supporting enterprise security solutions using Palo Alto, Zscaler and F5 technologies.
• Strong understanding of firewall technologies, VPN solutions (IPSec, SSL VPN, DMVPN), secure remote access and network security best practices within large enterprise environments.
• Experience producing High Level and Low Level Designs (HLDs/LLDs), technical documentation and supporting complex infrastructure change and lifecycle management.
• Solid networking knowledge including TCP/IP, routing, switching and WAN technologies, with the ability to troubleshoot across security and network infrastructure.
• Desirable experience with Check Point, Juniper, Blue Coat, Cisco networking (Catalyst/Nexus), Wireless, Cisco ISE/802.1X, QoS and Infoblox DNS.

Interviews: August 2026

Start Date: September 2026