IEC 62443 is an international standard that focuses on cybersecurity for Industrial Automation and Control Systems (IACS). It was developed by the ISA99 committee in collaboration with the IEC (International Electrotechnical Commission) and is used globally to protect Operational Technology (OT) against cyber threats.
IEC 62443 aims to create a common framework for managing cybersecurity in industrial environments. It covers the entire lifecycle – from design and development to operation and maintenance – and targets all stakeholders in the value chain: manufacturers, system integrators, service providers, and facility owners.
IEC 62443 is divided into several parts, each addressing different aspects of security:
Part
IEC 62443-1-1 Terminology, concepts, and models
IEC 62443-2-1 Security program requirements for facility owners
IEC 62443-2-4 Security program requirements for service providers
IEC 62443-3-2 Risk assessment and system design
IEC 62443-3-3 System requirements and security levels (SL1–SL4)
IEC 62443-4-1 Secure product development requirements
IEC 62443-4-2 Technical security requirements for components
For example, IEC_62443-3-2_EN describes how to conduct risk assessments to design secure systems, while IEC_62443-2-4-EN focuses on requirements for service providers involved in integration and maintenance.
The standard is particularly important as industrial systems are increasingly connected to the internet (IIoT) and thus vulnerable to cyber attacks. IEC 62443 complements IT-focused standards like ISO 27001 by considering the unique conditions in OT environments – such as real-time requirements, physical security, and lifecycle management.
It is also used as a basis for compliance with regulations like the NIS2 directive in the EU. NIS and NIS2 require critical infrastructure operators to implement robust cybersecurity measures.
The implementation follows the standard in three steps:
Risk analysis – Identify threats, vulnerabilities, and consequences.
Zone division – Divide the system into logical zones and define security levels.
Technical and organizational measures – Implement controls, training, and processes.
In reality, it may be necessary to adapt the content and sequence of all steps to better match each company's unique conditions and needs.
At Defensify, we help our clients get started and understand the IEC 62443 standard. Our working model allows us to customize the structure, content, and implementation of IEC 62443 to fit your specific challenges and needs.