Expert, hands-on skills in at least three of these areas, and working knowledge of most of the others: firewalls (Fortinet preferred), OT network monitoring (Nozomi, Dragos or similar), secure remote access (Xona or similar), Active Directory (Group Policy, RADIUS, LDAP), PKI, SIEM, Centralized security management platforms, application control (Trellix or similar), backup and recovery, Windows and Linux server build (hardening & virtualization), and hardening of field devices (IEDs, RTUs and gateways). Applied knowledge of IEC 62443 on real projects (especially parts 3-2, 3-3 and 2-4), working knowledge of NERC CIP, NIS2, CRA, IEC 62351 and NIST, and a sound understanding of substation and grid automation systems and protocols such as IEC 61850, DNP3, IEC 60870-5-104 and Modbus.