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Network Security Engineer

ManTech

Chantilly, VAJobSeen 3mo agoSeen in employer's feed 3 days ago

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At a glance

Compensation
No compensation found
Location
Chantilly, VA
Work Authorization
Not specified

Olive focuses on jobs in the United States, including remote roles you can work from there.

Requirements

Credentials this posting asks for.

CCNA Certification Or Equivalent Routing/Switching Technical Certification, requiredDoD 8570 IAT Level II Certification, requiredSecurity+ DoD 8570.1 / DoD 8140.01 (IAT III Level) Certification, requiredTS/SCI clearance, required

Job overview

ManTech is hiring a Network Security Engineer. ManTech seeks a motivated, career‑oriented Network Security Engineer to join its team in Chantilly, VA, working onsite to provide Tier II/III network security engineering support, design advanced WAN/LAN solutions, and collaborate with internal teams and sponsors.

Key focus areas include Perform Tier II and Tier III network security engineering support while assisting in designing advanced WAN, LAN, and data center solutions, Monitor and configure networks using SolarWinds, Cisco Firepower FMC, and Cisco ISE to analyze complex requirements and ensure functional infrastructure, and Create, maintain, and interpret detailed technical network security diagrams, routing topology schemas, and hardware configuration baselines.

Preferred (not required): SolarWinds, Cisco Firepower FMC, Cisco ISE, and ITIL Service Lifecycle.

Skills & qualifications

RequiredNice to have

Skills

SolarWinds, nice to haveCisco Firepower FMC, nice to haveCisco ISE, nice to haveITIL Service Lifecycle, nice to haveWAN, nice to haveLAN, nice to haveData Center Solutions, nice to haveMicrosoft Windows Systems, nice to haveHP SANs, nice to haveVMware Products, nice to haveVPNs, nice to haveGRE Tunnels, nice to haveBGP, nice to haveOSPF, nice to haveVLANs, nice to haveVRFs, nice to haveKGs, nice to haveCisco ACI, nice to haveAnsible, nice to haveDesired State Configuration (DSC), nice to haveCisco Secure Firewall, nice to haveBICSI Standards, nice to haveFiber Termination, nice to haveCat 5 Cabling, nice to haveNSTISSAM TEMPEST/2-95, nice to haveCNSSAM TEMPEST/01-13, nice to have

Qualifications

High School Diploma or GED, required7+ Years Experience in Network Security Engineering, requiredCCNA Certification or Equivalent Routing/Switching Technical Certification, requiredDoD 8570 IAT Level II Certification, requiredSecurity+ DoD 8570.1 / DoD 8140.01 (IAT III Level) Certification, requiredCurrent Active TS/SCI Clearance, requiredBachelors Degree in Engineering Discipline, nice to have

Full job description

MANTECH seeks a motivated, career and customer-oriented Network Security Engineer to join our team in Chantilly, VA. This is an onsite position.

Responsibilities include but are not limited to:

  • Perform Tier II and Tier III network security engineering support, while assisting in designing advanced WAN, LAN, and data center solutions.

  • Monitor and configure networks utilizing SolarWinds, Cisco Firepower FMC, and Cisco ISE to analyze complex network requirements and ensure complete, functioning infrastructure

  • Create, maintain, and interpret highly detailed technical network security diagrams, routing topology schemas, and robust hardware configuration baselines

  • Coordinate across large internal teams, stakeholders, and Sponsor authorities to drive infrastructure agendas and successfully navigate systems engineering processes

  • Participate in all phases of the ITIL Service Lifecycle, including submitting Change Requests and maintaining security event monitoring policies

  • Evaluate current network security architectures, inventory complex routing pathways, and recommend process improvements to optimize performance and throughput

  • Deliver end-to-end functional analysis, requirements specification, cost estimation, and engineering package releases for customer production IT environments

Minimum Qualifications:

  • High School Diploma or GED with 7+ years of progressively responsible experience in Network Security Engineering, Network Analysis, or a related technical discipline

  • Cisco Certified Network Associate (CCNA) certification, or equivalent routing/switching technical certification, ex., Juniper Networks Certified Associate – Junos (JNCIA-Junos)

  • DoD 8570 IAT Level II Certification, e.g., Security+ DoD 8570.1 / DoD 8140.01 (IAT III Level) certification required within 6 months of hire, e.g., SecurityX

Preferred Qualifications:

  • Bachelors degree in an engineering discipline

  • Experience using and administering SolarWinds alongside deep knowledge of Microsoft Windows Systems, HP SANs, and VMware products

  • Advanced experience managing VPNs, GRE tunnels, routing protocols (BGP E/I, OSPF), VLANs, VRFs, and configuring KGs

  • Strong familiarity with Cisco ACI, data center fabric best practices, Ansible, and Desired State Configuration (DSC)

  • Strong familiarity with Cisco Secure Firewall ( Firepower FMC)

  • Practical knowledge of BICSI standards, terminating fiber and Cat 5 cabling, as well as familiarity with NSTISSAM TEMPEST/2-95 and CNSSAM TEMPEST/01-13 guidelines

Clearance Requirements:

  • Must have a current and active TS/SCI clearance

Physical Requirements:

  • The person in this position must be able to remain in a stationary position 50% of the time. Occasionally move about inside the office to access file cabinets, office machinery, or to communicate with co-workers, management, and customers, via email, phone, and or virtual communication, which may involve delivering presentations.

MANTECH International Corporation considers all qualified applicants for employment without regard to disability or veteran status or any other status protected under any federal, state, or local law or regulation.

If you need a reasonable accommodation to apply for a position with MANTECH, please email us at [email protected] and provide your name and contact information.

How this job compares

Set against the 444 open Network Security Engineer jobs on Olive Jobs, counted November 14, 2026.

Pay
  • This postingNot listed
  • Virginia median$105–176K/yr30 salary ranges
Openings
Olive Jobs lists 36 open Network Security Engineer jobs in Virginia and 444 across the US. 4% of them nationwide are listed as remote or flexible.
Hiring the most in Virginia
Experience
This posting asks for at least 7 years of experience; Network Security Engineer postings that state a minimum ask for 7 years at the median (421 postings).
Education
This posting asks for a high school diploma; 107 of the 444 open Network Security Engineer jobs (24%) ask for a high school diploma or higher.

Counted across the open, public US postings on Olive Jobs on November 14, 2026. Figures based on too few postings are left out.

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