GB 🔐 Making Industrial Security Real: How IEC 62443 Helps You Scale Cyber Defence with Confidence
Thierry M.
Cybersecurity Director | GRC & OT/IT Risk Advisor | French "CDI Senior" compliant | IEC 62443–61508 Synergy | ISO 27001, NIS2, EBIOS RM | Fail-Safe / Fail-Secure | CentraleSupélec | MSc Cybersecurity
🎯 With Educational Insights from Schneider Electric’s EcoStruxure™ Platform
🚨 Why OT Cybersecurity Needs Rethinking
Industrial systems — the ones that power our grids, automate our factories, and control our railways — were never built with today’s cyber risks in mind. Air gaps are gone. Remote access is the norm. Ransomware hits harder than ever.
While many boardrooms are familiar with ISO 27001 for IT security, IEC 62443 is the standard designed for Operational Technology (OT). It scales cybersecurity from the device level up to entire factories — and even across ecosystems of plants.
📌 IEC 62443 isn't just another compliance box. It's a practical framework, used by leaders like Schneider Electric, to secure over 450,000 installations globally through its EcoStruxure™ platform.
📐 What Is IEC 62443?
IEC 62443 is a modular cybersecurity standard for Industrial Automation & Control Systems (IACS). It applies at different levels:
🔧 Devices & Components → Are they secure by design? 🏗️ Systems & Architectures → Are they segmented and hardened? 👤 People → Are they trained and qualified to implement security?
It defines Security Levels (SL1 to SL4) based on how advanced a potential attacker is:
SLThreat ProfileExampleSL1Accidents, errorsUntrained operatorSL2Basic cybercriminalsMalware or phishingSL3Organised attackersHacktivists, sabotageSL4Nation-state actorsAPTs, cyber warfare
📍 Takeaway: Not every system needs SL4. But every business needs to define its target SL (SL-T) based on real threats.
🧱 Defence-in-Depth Made Practical
Think of a medieval castle: moats, towers, guards. The same principle applies to industrial security:
🔹 Inventory first – Know what you have 🔹 Segment IT/OT – Don’t let office PCs touch your robots 🔹 Firewalls and DMZs – Create layered perimeters 🔹 Internal zoning – Keep safety systems isolated from HMIs 🔹 Harden endpoints – Remove unused ports, disable telnet 🔹 Continuous monitoring – Patch, log, detect, respond
👉 Schneider Electric applies all these layers through EcoStruxure™, integrating IT and OT security into a unified control architecture.
📊 Security Level Progression in Action
🔹 SL1 – Basic hygiene ✓ Passwords, access logs, network segregation → e.g. Low-risk wastewater plant
🔹 SL2 – Intermediate protection ✓ VPNs, intrusion detection, RBAC → e.g. Smart food-processing plant with remote maintenance
🔹 SL3 – Advanced resilience ✓ MFA, SIEM, time sync, secure components → e.g. National rail operator or nuclear facility
📌 EcoStruxure™ delivers SL1–SL3 based on your zone-specific needs. It’s not all-or-nothing — it’s precision-driven.
🧰 What If You Can't Replace Old Systems?
Legacy PLCs? No encryption? No problem.
IEC 62443 allows compensating controls:
🔸 Use modern firewalls and jump servers 🔸 Enforce network restrictions 🔸 Monitor access and anomalies
Schneider Electric supports brownfield deployments, layering modern protection over aging but mission-critical OT.
🏅 Why Certification Matters
🔒 Certified Devices → IEC 62443-4-2 (e.g. PLCs, gateways) 🏗️ Certified Systems → IEC 62443-3-3 (zone/conduit-based architectures) 👤 Certified People → TÜV, ISA Secure, exida (e.g. integrators, architects)
📌 Buyers can demand certified SLs. Vendors can prove their security claims. 📌 Certification gives procurement and governance teams a common language.
🌐 EcoStruxure™: Schneider’s Scalable Security Platform
🔸 Connected Products → Secure PLCs, drives, sensors 🔸 Edge Control → SCADA, HMIs with network segmentation 🔸 Apps & Analytics → Secure cloud platforms for monitoring & management
🧠 Schneider maps these layers to IEC 62443 requirements, providing real-world, SL-aligned security that scales from a single line to a global network of plants.
💰 Budgeting & Roadmapping for C-Level
Security is an investment — not an afterthought.
Security LevelCostValueSL1LowMinimal protectionSL2ModerateResilient operationsSL3HigherStrategic risk control
🔹 SL2 is today’s realistic baseline for all modern factories 🔹 SL3 is mandatory for critical infrastructure (rail, energy, pharma)
👉 Use a phased approach, prioritising high-risk zones first. Schneider’s team supports this journey step by step.
🧠 Final C-Level Takeaway
IEC 62443 is not a “badge” — it’s a map. Used wisely, it helps:
✅ Reduce downtime ✅ Prevent reputational loss ✅ Avoid regulatory fines ✅ Protect people and assets
📍 With EcoStruxure™, Schneider Electric turns this map into a deployable reality — at scale, across sectors, worldwide.
📚 Glossary