> Markdown version of [/jobs/ext/4628616-active-directory-engineer](https://www.wearedevelopers.com/jobs/ext/4628616-active-directory-engineer). Every page supports `.md` or `Accept: text/markdown`. Links point to the HTML versions so they work for humans too. Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md). --- # Active Directory Engineer - **Company:** Oxford Global Resources - **Location:** United States - **Experience:** Expert - **Contract:** Contract - **Skills:** Microsoft Access, Active Directory, Domain Controllers, Authentication Protocols, Computer Networks, Data Integrity, Domain Name System (DNS), Supervisory Control and Data Acquisition (SCADA), Kerberos (Protocol), Lightweight Directory Access Protocols (LDAP), Uptime, Windows Servers, NT LAN Manager, Public Key Infrastructure, Information Technology, Process Control Systems, Network Server, GXP, Legacy Systems - **Published:** November 7, 2026 - **Apply:** https://www.dice.com/job-detail/4da798dc-8cdc-4aea-9e3f-16c5915b2693 ## About the Role 10+ years of hands-on Active Directory engineering experience in large, complex enterprise environments Deep expertise in multi-forest / multi-domain AD architecture, forest and domain trusts, sites and replication, DNS, PKI, Group Policy, and authentication protocols (Kerberos, LDAP/LDAPS, NTLM) Strong experience designing and hardening Windows Server and domain controller infrastructure Experience implementing tiered administration models and securing privileged access (Tier 0 protection, PAW/jump-host design, PAM) OT / Industrial IT Knowledge (Critical) Demonstrated, in-depth understanding of IT/OT Active Directory segregation including isolated OT forest design, controlled or one-way trust models, selective authentication, and avoidance of IT/OT authentication dependencies Strong working knowledge of the Purdue Model (ISA-95) for industrial control system segmentation, including Levels 0 5 and the role of the Industrial DMZ (IDMZ) in directory and authentication architecture Experience designing directory and authentication services within OT / ICS / SCADA / process-control network environments Familiarity with OT cybersecurity standards and frameworks such as IEC 62443 and NIST SP 800-82 Understanding of OT operational constraints (uptime, change control, legacy systems, validated/GxP environments) and how they influence directory design and migration Preferred Qualifications Prior delivery of OT-segregated directory services architectures in regulated or industrial settings (pharma, biotech, manufacturing, utilities) Familiarity with certificate lifecycle management platforms and enterprise PKI operations Experience integrating OT directory services with IDMZ components, jump servers, and privileged access solutions Relevant certifications such as Microsoft Certified: Identity and Access Administrator, GIAC GICSP, ISA/IEC 62443, or equivalent Experience in GxP / validated environments and associated documentation practices Key Deliverables Fully deployed, isolated OT AD forest and child-domain structure aligned to the approved Architecture Documented architecture, DNS/PKI configuration, trust model, and security baselines ## Description The Active Directory Engineer is a senior technical contributor responsible for the design, implementation, and transition of segregated Active Directory environments aligned to the approved Architecture for OT / Process Area networks. The role is central to establishing a secure, standards-aligned directory foundation that enforces robust IT/OT segregation and supports regulated manufacturing operations. This position focuses on establishing and operationalizing: A fully isolated Active Directory forest dedicated to OT / Process Area networks, with no trust dependencies that would compromise IT/OT separation Forest/Domain structures for OT networks as defined by the enterprise OT directory architecture baseline The engineer ensures that all directory services are implemented securely, consistently, and in alignment with enterprise standards, regulatory expectations (e.g., GxP / data integrity), and Purdue Model segmentation principles.