Network Security Engineer, Lead; Top Secret Clearance SCI & SAP eligibility

Position: Network Security Engineer, Lead (Top Secret Clearance with SCI & SAP eligibility)
Overview AMERICAN SYSTEMS, a 100% employee-owned federal government contractor, is seeking a Lead Network Security Engineer to support a critical national security mission in a highly classified environment in Dallas, TX. This position requires the ability to work independently in a complex, security-focused environment.

We’re seeking an experienced network professional with strong hands-on experience in enterprise networking, network security, firewall administration, and infrastructure troubleshooting. Experience administering and troubleshooting enterprise firewall technologies is required, including platforms such as Cisco Firepower, Firepower Management Center, Palo Alto, Fortinet, Check Point, or similar solutions.

Experience with Cisco ISE, network access control, authentication, authorization, or 802.1X is also valued.

Responsibilities As a Lead Network Security Engineer, you will:

Lead secure network engineering, administration, and operational support in a highly classified environment.

Design, implement, configure, and maintain enterprise network infrastructure, including:

Routers and switches | Firewalls | VLANs | ACLs | VPNs Network segmentation | High-availability architectures

Administer, monitor, and troubleshoot enterprise firewall environments.

Configure and manage firewall policies, access rules, NAT, VPNs, security zones, logging, and monitoring.

Support and troubleshoot Cisco Firepower and Firepower Management Center (FMC). Cisco Firepower experience is preferred.

Troubleshoot complex Layer 2 and Layer 3 networking, routing, switching, firewall, connectivity, and access control issues.

Support AAA, authentication, authorization, accounting, and network access control requirements.

Configure and troubleshoot 802.1X, VPN, and network access control solutions.

Support Cisco ISE environments, including authentication, authorization, policy enforcement, and network access control. Cisco ISE experience is preferred.

Support RMF, STIG, secure configuration, vulnerability remediation, and compliance activities.

Develop and maintain network diagrams, implementation plans, SOPs, configuration documentation, and technical reports.

Partner with cybersecurity, systems administration, and mission teams to deliver secure and resilient network solutions.

Support incident response, outage resolution, root cause analysis, change implementation, and network remediation efforts.

Monitor network performance and recommend improvements to strengthen security, availability, reliability, and performance.

Provide technical leadership and guidance to network engineering and operations personnel.

QualificationsU.S. citizenship required.

Active TS/SCI clearance with SAP eligibility required.

Bachelor’s degree in a related technical field, or additional relevant experience in lieu of a degree.

Eight or more years of experience in network engineering, network operations, or network security.

Experience working in enterprise, defense, intelligence, federal government, or highly regulated environments.

Strong hands-on experience with enterprise networking, including:

Routing and switching | Layer 2 and Layer 3 troubleshooting | VLANs and subnetting

Access control lists, or ACLs | Network addressing and design | VPN technologies

Network segmentation | Resilient network architectures

Hands-on experience administering and troubleshooting enterprise firewalls.

Experience with one or more of the following firewall platforms:

Cisco Firepower and FMC preferred | Palo Alto Networks | Fortinet | Check Point Other commercial or government enterprise firewall platforms

Experience with firewall policy administration, rule management, NAT, VPNs, security zones, logging, monitoring, and troubleshooting.

Experience supporting AAA, 802.1X, RMF, STIG, secure configuration, and network access control requirements.

Cisco ISE experience preferred, particularly with:

Authentication | Authorization | Accounting Policy enforcement | Network access control

Active DoD 8140/8570 IAT II certification, such as:
Security+ CE, CySA+, SSCP, or equivalent certification

Experience troubleshooting Cisco routers, switches, firewalls, and enterprise network infrastructure.

Ability to work independently, lead technical efforts, and resolve complex network and security issues.

Strong written and verbal communication skills.

Additional Experience We Value The following experience is helpful but not required:

Experience supporting highly compartmented or special-access classified environments.

Cisco…