Network Security Specialist

All hired employees are expected to have experience with Microsoft Copilot and / or an approved equivalent AI solution.

Data Systems Analysts, Inc. (DSA) is seeking a TS/SCI cleared Network Security Specialist to secure, engineer, and defend enterprise network systems in a secure DoD environment. The Network Security Specialist will perform hands‑on security configuration, boundary defense engineering, vulnerability remediation, and device hardening for Cisco based network infrastructure.

This position is onsite in Charlottesville, VA.

• Configure and review firewall rules, access control lists, ports, protocols, services, VPN connections, network flows, and boundary protection controls.
• Configure, validate, and audit security configurations for Cisco routers, switches, firewalls, and related network infrastructure.
• Support active network security operations, boundary defense engineering, and continuous hardening for enterprise network systems.
• Support incident response activities by performing technical analysis of network related alerts, logs, firewall events, syslog data, and authentication events.
• Support change control reviews by assessing proposed network changes for cybersecurity impacts, configuration vulnerabilities, and security architecture alignment.
• Monitor network security posture through syslog alerts, configuration management tools, and packet‑level analysis.
• Conduct, analyze, and remediate vulnerability scans using ACAS, Tenable Nessus, STIG Viewer, and other approved DoD tools.
• Analyze vulnerability findings, identify false positives, engineer technical workarounds, and execute remediation actions across network devices.
• Implement and validate DISA STIG compliance, SCAP benchmarks, security baselines, and device hardening requirements.
• Develop and maintain technical network security documentation including device hardening procedures, network diagrams, and Ports, Protocols, and Services (PPS) listings.
• Support technical engineering assessments and security reviews to maintain authorization sustainment activities.
• Prepare technical security status updates, vulnerability remediation roadmaps, and network security risk briefings for engineering teams and stakeholders.

• BS degree in Engineering, Computer Science, or related field
  • Experience may be substituted for degree.
• TS/SCI Clearance
• CCNA certification

• Minimum 4 years of experience supporting network security engineering, secure network operations, boundary defense, or hands‑on network administration.
• Working knowledge of Cisco routers, switches, firewalls, Cisco ASA, Cisco Firepower, Cisco Secure Firewall, Cisco ISE, Catalyst, Nexus, ISR, or ASR platforms.
• Working knowledge of routing, switching, VLANs, ACLs, firewall policies, ports, protocols, VPNs, IPsec, NAT, DNS, DHCP, subnetting, logging, and boundary protection.
• Ability to design and review network diagrams, firewall rule sets, data flows, ports and protocols, and system interconnections for security vulnerabilities.
• Demonstrated understanding of network hardening practices, secure protocols, network security architecture, and boundary defense concepts.
• Experience coordinating with network engineers, systems administrators, security analysts, and mission partners to resolve technical security findings.
• Hands on experience with ACAS, Tenable Nessus, STIG Viewer, SCAP, and network vulnerability remediation processes.
• Experience applying, validating, or remediating vulnerability findings and DISA STIGs for network devices.
• Experience developing or maintaining technical configuration standards, ports and protocols lists, network topology diagrams, and device configuration baselines.
• Familiarity with applying and verifying security controls on network hardware to support technical authorization maintenance.
• Experience supporting network security activities within the DoD, Intelligence Community, or other secure enterprise environment.
• Knowledge of NIST SP 800‑53 security controls (specifically Network/Access Control families), DISA Network Infrastructure STIGs, and secure network…