Network Engineer SME - Top Secret Clearance REQUIRED

i3, LLC; Chantilly (VA); On-site; USD 150,000 - 190,000; Full time

Job summary

i3, LLC is seeking a Network Engineer - SME to lead the design, implementation, and optimization of secure, resilient network infrastructures across complex environments. You will drive zero-trust design, cross-enclave interoperability, and modernization efforts while ensuring secure communications for mission-critical operations.

The role requires extensive experience in enterprise networks, security architecture, and leadership across security, architecture, and operations teams.

Qualifications

• Bachelor's degree in IT/Networking or related field required.
• 10+ years of experience in enterprise network design and operation.
• Experience with zero-trust architecture and cross-enclave interoperability.
• Experience in secure, highly regulated or classified environments.

Responsibilities

• Design and implement enterprise network architectures for secure, mission-critical ops.
• Lead zero-trust design initiatives and cross-enclave interoperability solutions.
• Optimize network performance, reliability, and security across multi-enclave environments.

Skills

Enterprise networking

Zero-trust

Routing & Switching

Network security

Terraform

Ansible

Docker

Kubernetes

OpenShift

Python

.NET/C#

Active Directory

LDAP/OpenLDAP

Entra ID

Keycloak

Education

Bachelor's degree in IT/Networking

Master's degree in IT/Networking

Security related certifications (CCNP/CCIE/CISSP)

Tools

AWS GovCloud/SC2S/C2S

GCP

Nutanix

Prism Central

NDFS

Cisco switching/routing/firewalling

IPSEC, DMVPN, SD-WAN

Terraform

Ansible

Docker

Kubernetes

OpenShift

Cloud networking

VPC configuration

Elasticsearch/OpenSearch/Splunk

GitLab CI/CD

Job description

Network Engineer - SME

\"Bachelors required Minimum 10 years experience

The Network Engineer (SME) serves as the principal authority for network architecture, zero-trust network design, and cross-enclave interoperability. This role leads the design, implementation, and optimization of resilient, secure network infrastructures supporting mission-critical operations. The SME provides strategic and technical leadership in network modernization, security architecture, and performance optimization while ensuring secure and reliable communications across complex, multi-enclave environments.

Key Responsibilities

• Design and implement enterprise network architectures that support secure, mission-critical operations.


• Lead zero-trust network design initiatives and cross-enclave interoperability solutions.


• Optimize network performance, reliability, and security across complex, multi-enclave environments.


• Establish and enforce network security architecture standards and governance processes.


• Drive network modernization efforts aligned with enterprise strategy and zero-trust principles.


• Ensure secure communications and connectivity across classified and highly regulated environments.


• Provide technical leadership for network infrastructure planning and implementation.


• Partner with security, architecture, and operations teams to maintain resilient network systems.

Required Skills

Extensive experience designing and supporting enterprise network environments. Strong expertise in routing, switching, firewalls, VPNs, network security, and access control technologies. Experience implementing zero-trust architectures and secure communications solutions. Advanced troubleshooting and network performance analysis skills. Experience supporting mission-critical, highly secure, or regulated environments. Strong leadership, communication, and technical documentation skills.

Unique Skills / Technical Requirements

• Air-gapped hybrid cloud and on-premises operational environments, including complex multi-enclave ecosystems


• AWS GovCloud/SC2S/C2S and GCP cloud platforms Nutanix host and cluster configuration, management with Prism Central, and NDFS configuration/management


• Cisco switching, routing, firewalling, and site-to-site functionality (such as IPSEC, DMVPN, and SD-WAN)


• Locally hosted GPU servers


• Multi-tenant Cross-Domain Solutions (CDS)


• Infrastructure-as-Code (Terraform, Ansible)


• Containerization and orchestration (Docker, Kubernetes, OpenShift)


• Cloud-native security implementation and security accreditation processes


• Advanced GitLab CI/CD pipelines and DevSecOps practices


• Enterprise database services (RDS, RDS Aurora, DynamoDB)


• Serverless architectures (Lambda)


• Cloud networking and VPC configuration


• Monitoring, logging, and data platforms (Elasticsearch, OpenSearch, Splunk)


• Microservices architecture and API Gateway implementation


• Development experience with Python, .NET/C#, and related languages


• Identity and access services (Microsoft Active Directory, LDAP / OpenLDAP, Entra ID, Keycloak)


• High-assurance cross-domain and encryption solutions (TACLANE, NCAP)


• Cloud cost-optimization techniques


• Operating Systems: Linux (e.g., Rocky, RedHat, Amazon, Ubuntu), Windows, and Mac OS

Preferred Skills

Master's degree in Information Technology, Network Engineering, Cybersecurity, or related field. Experience supporting federal, defense, intelligence, or classified network environments. Expertise with multi-enclave or cross-domain network architectures. Experience with cloud networking, software-defined networking (SDN), and hybrid cloud environments. Knowledge of security accreditation processes and compliance frameworks. Relevant certifications such as CCNP, CCIE, CISSP, JNCIP, JNCIE, AWS Advanced Networking, or equivalent.