Leidos' Digital Modernization sector is seeking a Senior Firewall Engineer to support the GSM-O effort. This position is located at the Pentagon and is 100% on-site. This role requires an engineer who can design, implement, and manage complex firewall solutions to ensure the security and integrity of network infrastructure. The ideal candidate has experience with firewall technologies including Cisco ASA, Juniper SRX, and Palo Alto, as well as a strong background in security networking.

Primary Responsibilities:

• Design, Implement Manage firewall solutions using Cisco ASA/Firepower, Juniper SRX and Palo Alto.

• Monitor firewall performance and security logs to identify and mitigate potential threats.

• Develop and enforce network security policies and procedures.

• Perform system audits to ensure compliance with standards and regulations.

• Collaborate with other IT, Security and Network teams to integrate firewall solutions.

• Troubleshoot and resolve network and firewall related issues promptly and document within ticket systems.

• Maintain and update firewall configurations (security polices/firewall ACLs as approved by Change Management)

• Serve as a People Leader for personnel supporting the Firewall Task Area: Serve as the focal point for all firewall tasks, operations, projects, and assessments.

• Ensure all tasks are delivered according to timelines

• Provide written reports and oral briefings to the Government Task Lead and PMO Team

• Conduct annual performance assessments to include periodic check ins.

• Validate/approve time charging for both Leidos and vendor personnel.

• Provide coaching/mentoring to personnel.

• Develop and Execute Continual Service Improvement technical strategies to modify and enhance operational processes and impact strategic project/program goals and business results.

Required Clearance and Certifications:

• Must have, at minimum, an active DoD Top Secret security clearance with ability to obtain TS/SCI. An active TS/SCI is preferred.
• Must have DoD 8570 IAT II or higher certification prior to start.
• Must have a Juniper, Cisco, or Palo Alto certification prior to start.

Required Qualifications:

• BS degree and 12+ years of directly relevant experience. Additional military or relevant work experience may be considered lieu of a degree.
• 3+ years of Firewall experience within the DoD environment
• Demonstrated knowledge in planning, directing, and managing a Firewall Team in an organization similar in size to this acquisition
• Demonstrated knowledge of Implementation of Perimeter and Internal Firewalls (both physical and virtual contexts)
• Demonstrated advanced experience in managing standard baseline configuration across numerous firewalls
• Demonstrated advanced experience in evaluating rules to ensure maximum security while minimizing redundancy in rules
• Demonstrated experience with researching and fielding new and innovative firewall technology

About our Program:

Through the J6 Penetration Handling, Incident, System Health (PHISH) support services task order on the GSM-O contract, we provide IT products, services and solutions to the Pentagon and other DoD offices and agencies for them to meet mission and business requirements. Our Cybersecurity team performs cyber defensive actions in support of J6 to prevent, detect, respond and recover from adversarial activities.

If you're looking for comfort, keep scrolling. At Leidos, we outthink, outbuild, and outpace the status quo — because the mission demands it. We're not hiring followers. We're recruiting the ones who disrupt, provoke, and refuse to fail. Step 10 is ancient history. We're already at step 30 — and moving faster than anyone else dares.

Original Posting:

March 6, 2026

For U.S. Positions: While subject to change based on business needs, Leidos reasonably anticipates that this job requisition will remain open for at least 3 days with an anticipated close date of no earlier than 3 days after the original posting date as listed above.

Pay Range:

Pay Range $131,300.00 - $237,350.00

The Leidos pay range for this job level is a general guideline only and not a guarantee of compensation or salary. Additional factors considered in extending an offer include (but are not limited to) responsibilities of the job, education, experience, knowledge, skills, and abilities, as well as internal equity, alignment with market data, applicable bargaining agreement (if any), or other law.