April 12, 2026
Checklist for Deploying 5G in Assembly Lines
read now
BREAKING NEWS: Firecell and Accelleran Merge to Deliver Sovereignty-Compliant Industrial Private 5G Learn more
Private 5G networks are transforming industries like manufacturing and logistics but come with heightened cybersecurity risks. The IEC 62443 standard offers a structured approach to secure these networks, focusing on availability, integrity, and safety rather than just data confidentiality. It addresses threats ranging from accidental errors to advanced attacks, ensuring robust protection for Industrial Automation and Control Systems (IACS).
Start by evaluating your network’s vulnerabilities and aligning it with IEC 62443’s requirements to ensure both security and compliance.
IEC 62443 Security Levels and Implementation Framework for Private 5G Networks
Evaluate your network’s security to pinpoint vulnerabilities, understand its architecture, and address gaps in line with IEC 62443 standards.
A gap analysis helps you measure your current security setup against IEC 62443 requirements. Start by defining the System Under Consideration (SUC) – this includes the physical and logical boundaries of your private 5G network, like edge devices (e.g. sensors, PLCs), gateways, core network functions, and cloud interfaces. Then, perform a high-level risk assessment to identify critical functions, such as safely starting or stopping processes and maintaining safety integrity.
Create a detailed inventory of all assets – hardware, firmware, and network protocols, including OT-specific ones – to map out communications effectively.
Bring together a team of OT engineers, IT security experts, and production managers to assess risks thoroughly. Compare your current setup against the seven foundational requirements from IEC 62443-3-3: identification control, usage control, system integrity, data confidentiality, restricted data flow, timely response, and resource availability. Use automated scans alongside manual checks of configuration files and firewall rules to identify vulnerabilities.
Once you’ve mapped these gaps, organise your network into secure zones and controlled conduits.
Zones group assets – like 5G core functions, PLCs, or HMIs – with similar security needs and risk levels. Conduits, on the other hand, are controlled communication pathways between zones, enforced through measures like firewalls or access control lists.
Segment your network based on functional roles, geographical location, or specific Security Level (SL) targets, ranging from SL 1 to SL 4. IEC 62443-3-2 emphasises isolating business, safety-related, wireless, and temporary assets based on their risk profiles.
When setting up conduits, adopt a "deny by default" strategy – block all traffic initially, then allow only necessary and justified protocols or communication paths. Establish an OT DMZ as a buffer between your enterprise IT network and the private 5G/OT environment to prevent direct access. Document everything with detailed network diagrams that clearly show zone boundaries, conduit rules, and assigned Security Levels to aid in audits.
"Assume layers fail. Design so a single failure doesn’t become a plant-wide event." – IoT Worlds
The next step is to tackle supply chain risks tied to third-party components.
Third-party components, such as radio units or core network software, can introduce vulnerabilities into your private 5G network. To mitigate these risks, audit vendors using IEC 62443-4-1 (focused on secure development lifecycles) and IEC 62443-4-2 (covering technical component requirements).
Ask vendors for a Software Bill of Materials (SBOM) to identify all software components and libraries, making it easier to track vulnerabilities. Confirm whether components are certified by third-party standards like ISASecure CSA (Component Security Assurance), which evaluates products against IEC 62443-4-2. Ensure the vendor’s Capability Security Level (SL-C) aligns with the Target Security Level (SL-T) required for the zone where the component will be deployed.
Request hardening guides from vendors to disable unnecessary services, ports, and protocols. If a component doesn’t meet security requirements, implement compensating measures like industrial firewalls or enhanced segmentation. Prioritise vendors committed to "secure by design" principles, where security features are integrated from the beginning rather than added later.
Once you’ve evaluated your network, the next step is to implement security measures that align with IEC 62443’s seven foundational requirements. These measures focus on areas like network segmentation, encryption, access management, and securing essential network functions – key for safeguarding private 5G networks in industrial settings.
Effective segmentation is built around the zones and conduits you’ve already defined. By dividing the network into logical, risk-based zones, you can limit the potential impact of a breach. Each zone – whether it’s for safety systems, control networks, or field devices – should have an assigned Target Security Level (SL-T), ranging from SL1 (basic protection against casual breaches) to SL4 (defence against highly skilled attackers with significant resources).
Zones should be defined based on the potential consequences of a compromise, not just their network location. For instance, safety-critical systems like Safety Instrumented Systems (SIS) often require SL4, while field devices like sensors may only need SL2. Conduits, which are controlled communication pathways between zones, should be secured with firewalls and access control lists adhering to a "deny by default" policy.
An emerging trend is identity-based microsegmentation, offering more precise control below Layer 3. This approach allows security policies to adapt dynamically based on device and user identity, rather than relying solely on network location.
"In a flat network, a single compromised engineering workstation, jump host, or OT server can become a launchpad for lateral movement [and] ransomware spread." – IoT Worlds
A real-world example from 2026 highlights this approach: an automotive manufacturing plant implemented an IEC 62443-compliant architecture with five security zones. By applying SL3 controls to robotic assembly and safety-critical equipment, they achieved a 60% drop in security incidents affecting production and gained better visibility into potential vulnerabilities.
IEC 62443 mandates unique identification and authentication for all users – whether human, process, or device – before granting access. To achieve this, use X.509 certificates for mutual authentication between 5G core elements and end devices, ensuring all components can verify each other’s identity.
For data security, apply TLS 1.3 for data in transit (e.g., MQTT over TLS) and AES-256 encryption for sensitive data at rest. Security Level requirements vary based on risk:
Role-Based Access Control (RBAC) is essential to limit authenticated users to only the actions necessary for their roles, reducing the potential impact of a breach. Sessions should be automatically terminated when no longer needed, and all active sessions should be monitored for anomalies. Additionally, ensure all 5G network functions and edge devices use signed firmware and secure boot mechanisms, relying on Trusted Platform Modules (TPM) or Hardware Security Modules (HSM) to block unauthorised code execution.
"You can’t just buy SL-3 certified components and assume you have an SL-3 system. Integration, configuration, and compensating measures all matter." – Secuvi
With encryption and access controls in place, the next step is to focus on securing your core network functions.
A defence-in-depth strategy is crucial for protecting 5G core elements such as the Access and Mobility Management Function (AMF), Session Management Function (SMF), and User Plane Function (UPF). Assign Security Levels to these core functions based on their risk profile – critical production systems often require SL3 or SL4, which involve hardware-based security and stringent controls.
Quality of Service (QoS) policies can help prioritise critical traffic, preventing resource exhaustion attacks that might disrupt availability. Instead of relying on a single perimeter, use industrial firewalls and secure remote access solutions at zone boundaries. Continuous monitoring is essential for automated asset discovery and classification, keeping your network inventory accurate. Real-time adaptation to network changes is also key, with dynamic policy updates based on identity, vulnerabilities, and risks. Start with the most vulnerable systems and gradually secure additional components.
"IEC 62443 was specifically designed to address the unique requirements and constraints of industrial control systems, where availability and integrity often take precedence over confidentiality." – IoT Security Institute
Achieving compliance with IEC 62443 is just the beginning – maintaining it requires ongoing vigilance through continuous testing, audits, and real-time monitoring. Industrial networks are constantly evolving, with new vulnerabilities and changes in network configurations appearing regularly. Without consistent oversight, your Achieved Security Level (SL-A) could fall short of your Target Security Level (SL-T). Let’s explore the key practices needed to sustain your security levels.
Regular testing is essential to ensure your network’s resilience. Vulnerability Assessment and Penetration Testing (VAPT) can uncover weaknesses in critical areas like your 5G core, RAN, and edge components. Start with automated scanning to identify known Common Vulnerabilities and Exposures (CVEs) across your network assets. Follow this up with manual reviews of firewall rules, access control lists, and device configurations to catch issues that automated tools might miss.
Before rolling out any 5G or Industrial Internet of Things (IIoT) device, conduct Security Acceptance Testing (SAT) to confirm it meets your security requirements. For systems aiming for SL-3 or higher, automated security checks are crucial to counter advanced threats. Penetration tests should focus on 5G-specific attack vectors, such as MQTT/Modbus hijacking, DNS hijacking, and SIM swapping. The core network, which handles sensitive user and manufacturing data, should be a primary focus since it’s a high-value target for persistent attacks.
In November 2021, Trend Micro’s Yohei Ishihara led a security assessment of a private 5G network designed to replicate a steelworks facility. This evaluation uncovered six critical attack scenarios, with five of them originating from signal interception within the core network. Their findings highlighted actionable steps for manufacturers, such as adopting encrypted protocols and VPNs to mitigate risks.
Testing alone isn’t enough – systematic audits are equally important. Regular reviews based on IEC 62443-2-4 ensure that system integrators have chosen, designed, and configured components to meet your security requirements. These audits help confirm that your systems continue to meet their original Security Level objectives, even as new threats emerge.
Before handing over an integrated system, system integrators must verify that it meets its Target Security Level through formal SAT. Regular audits should also focus on maintaining an up-to-date asset inventory, including hardware, software versions, and firmware, to track vulnerabilities effectively.
"The integrated system must meet a Target Security Level (SL-T) based on risk assessment. The actual protection achieved after deployment is the Achieved Security Level (SL-A)." – Secuvi
To comply with IEC 62443-3-3’s Foundational Requirement 6 (FR6), which calls for "timely response to events", you need continuous monitoring, accessible audit logs, and robust incident detection capabilities. Forward logs from network devices, firewalls, and multi-factor authentication tools to a Security Information and Event Management (SIEM) system or an OT-specific Security Operations Centre (SOC) for real-time threat detection.
For private 5G networks, monitoring should cover signalling protocols (NAS, DIAMETER), OAM&P interfaces, and Service-Based Architecture (SBA) APIs to identify potential exploits in the core network. Use Deep Packet Inspection (DPI) tools like Cisco Cyber Vision to gain OT-specific insights into flow data, helping to detect unauthorised changes or credentials sent over unencrypted protocols. Deploy Intrusion Detection/Prevention Systems (IDS/IPS), such as Snort, to analyse traffic in real time and identify threats like buffer overflows or stealth port scans.
VPN concentrators should be configured to immediately terminate sessions if policy violations occur. Meanwhile, Privileged Access Management (PAM) solutions can monitor remote sessions in real time and record maintenance activities, ensuring compliance with identity and access policies. Regular security drills are also essential to test and refine your incident response plans, ensuring your team can act swiftly and effectively when needed.
Achieving IEC 62443 compliance is a crucial step towards building lasting operational resilience. This framework offers a structured approach to securing industrial environments, even under the most challenging conditions. By categorising Security Levels (SL 1–4), organisations can align their security investments with actual threat landscapes, ensuring resources are used effectively without overspending or leaving vulnerabilities unaddressed.
As Impulse Embedded explains:
"The business case is straightforward risk reduction. Downtime, safety impacts, and reputational damage from OT ransomware or lateral movement are now common drivers for board-level investment".
Compliance also simplifies collaboration among stakeholders by standardising communication, making procurement more straightforward and ensuring security-by-design principles are upheld. Furthermore, it supports adherence to international regulations like the EU NIS2 Directive and the Cyber Resilience Act.
What sets IEC 62443 apart is its emphasis on long-term security management. Central to the framework is the Cybersecurity Management System (CSMS), which promotes ongoing improvement through a cycle of risk awareness, mitigation, and performance evaluation. This adaptability ensures organisations stay ahead of emerging threats. As Team Shieldworkz puts it:
"Compliance is not a one-time effort. Monitor your systems, test your controls, and update your CSMS regularly to adapt to new threats".
Another key component is zone-and-conduit segmentation, which helps contain breaches by isolating them, limiting lateral movement, and reducing the overall impact of incidents.
IEC 62443 is a crucial standard when it comes to cybersecurity for industrial automation and control systems (IACS). If you’re working on a private 5G network, the first step is to get to grips with its structure. This includes understanding its core elements: concepts, policies, system-level requirements, and component-specific requirements.
Once you’re familiar with the basics, focus on identifying the specific security levels and technical needs for your network. These could include measures like authentication, encryption, and network segmentation. To make implementation smoother, look for practical guides that explain how to apply these principles effectively to your 5G network setup.
To align Security Levels (SL1–SL4) with IEC 62443 standards, start by conducting a thorough risk assessment. This involves evaluating potential threat scenarios, the criticality of your systems, and the protections needed. Assign these security levels to zones – which are groups of assets sharing similar security requirements – and conduits, which are the communication channels connecting these zones. For areas with higher risks and potential impacts, apply stricter security levels to ensure they are well-defended against more advanced threats.
To show compliance with IEC 62443 during audits, you’ll need to present clear and detailed documentation proving your systems align with the standard’s security requirements. This means having evidence such as:
Additionally, keep thorough records of activities like assessments, configuration management, testing, and monitoring. These documents will demonstrate your commitment to maintaining a secure and compliant system.
