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)
Required Clearance and Certifications:
- Must have, at minimum, an active DoD Secret security clearance with ability to obtain TS/SCI. An active TS/SCI is preferred.
- Must have DoD 8570 IAT II or higher certification (Security+ CE or equivalent) 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 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
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.
We’re not looking for perfectly polished resumes or perfect fits. We’re looking for people who break limits, ask hard questions, and don’t wait to be told what’s next. At Leidos, we’re not following the roadmap — we’re redrawing it.
Original Posting:November 10, 2025For 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.
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.
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What We Do
We Are Leidos
For 50 years we have been tackling some of the biggest problems that face our nation and our world.
OUR MISSION
Through our culture of innovation and history of performance, we develop deep customer trust built on integrity and create enduring solutions that improve our world. Leidos is a science and technology solutions leader working to address some of the world’s toughest challenges in the defense, intelligence, homeland security, civil, and healthcare markets. The company’s 43,000 employees support vital missions for government and commercial customers. Headquartered in Reston, Va., Leidos reported annual revenues of approximately $11.09 billion for the fiscal year ended January 3, 2020.
Leidos was cited for the meaningful work employees perform that is challenging, impactful, and aligned with our customers’ missions as reasons professionals want to work and stay at our company. Leidos has also been named to lists including Forbes’ Best Employers for Diversity, Forbes’ America’s Best Employers for Women, Military Times Best for Vets Employers, and Ethisphere Institute’s World's Most Ethical Companies®.
Employees enjoy career enrichment opportunities available through mobility and development and experience rewarding relationships with supportive supervisors and talented colleagues and customers. Employees appreciate our flexible work environment, allowing for and encouraging a true work-life balance. Our professionals are also excited about our Employee Resource Groups, like the newly launched Collaborative Outreach with Remote and Embedded Employees (CORE), which strives to create an environment where every employee, regardless of location, feels fully engaged as a valued employee of Leidos.
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