By Dominique Verhulst, Global Head of Energy Segment, Nokia 

Mission-critical operational technology (OT) networks are the foundation of modern power grids. Working behind the scenes, they provide connectivity that enables physical processes, devices and infrastructure to maintain safe, efficient and uninterrupted power delivery. According to a 2026 IDC Spotlight, utilities need OT networks that provide extreme reliability, predictable performance and strong security by design to keep up with growing energy demands. 

OT networking challenges for utilities

The mission-critical OT systems that utilities rely on for power delivery have much more stringent networking demands than enterprise IT systems. For example, utility networks need to support OT systems with predictable low latency, highly accurate time synchronization and prioritized traffic delivery. They also need flexibility to keep supporting OT systems that have been running for decades. 

The makeup of today’s utility OT networks presents more challenges. These networks often feature siloed components built for specific applications. They are expensive and difficult for utilities to maintain and can’t readily adapt to the performance needs of digitalized OT systems. 

Beyond these technical challenges, utilities face significant pressure from regulators and customers to make their OT networks more resilient and cybersecure. Standards and regulations for utility OT environments are increasingly focused on availability and cyber risk reduction. 

How IP/MPLS and optical WANs can meet OT networking needs

Many utilities are considering wide area networks (WANs) based on modern IP/MPLS and optical technologies as a solution to these challenges. Used together, these technologies can securely interconnect substations, control centers and other grid sites with high capacity and low latency over virtually any distance. 

IP/MPLS and optical WANs designed for mission-critical OT networking can make grid operations more resilient and sustainable by enabling:

• Consistent, predictable performance for critical protection and control traffic.
• High availability and fast recovery to keep services running during network faults and maintenance periods.
• Simpler operations with architectures that support many services with a few flexible platforms.
• More robust cybersecurity with network designs that support advanced protection mechanisms and utility-specific security frameworks.
• Long-term cost reduction with modern architectures that enhance automation and visibility and extend infrastructure lifecycles.
• Deliver highly accurate time synchronization across the WAN to enable accurate network-based synchronization of all OT assets that require it.

By deploying OT-focused IP/MPLS and optical WANs, utilities can efficiently and securely support a wide range of use cases, including IEC 61850 automation, DER integration, grid protection automation and control, and AI-driven operations. 

Technologies that can power modern utility OT WANs

The good news for utilities is that there are many technologies and approaches that can help them take full advantage of IP/MPLS and optical WANs to address their biggest OT networking challenges. These include:

• Deterministic transport for critical control and protection traffic across the WAN, including the ability to prioritize, isolate and engineer paths.
• IP/MPLS and segment routing platforms that support automatic failure recovery and strict availability targets.
• Converged IP/optical transport that simplifies networking, reduces cost and improves resilience.
• Dense wavelength-division multiplexing (DWDM) technology that can ensure reliable communications between substations hundreds of kilometers apart.
• Network-wide synchronization enabled by IP/MPLS, which can meet the demands of digital substations and automation use cases based on the IEC 61850 standard.
• Stronger protection for OT systems through capabilities such as segmentation, zoning, controlled interconnection and quantum-safe encryption.
• Comprehensive visibility and assurance for OT systems enabled by capabilities such as monitoring, telemetry and analytics.
• Incremental modernization and coexistence with legacy systems.

What utilities should look for in an OT WAN solution

An ideal WAN solution will empower utilities to use these technologies and approaches to meet the stringent reliability and predictability demands of their mission-critical OT. It will combine IP and optical networks to provide an integrated transport foundation for these systems, complemented by user-friendly network automation, utility-focused network architectures and expert services.

IP/MPLS networks designed for mission-critical OT

Utilities need IP networks that provide high-availability routing and MPLS platforms designed to support essential capabilities for OT WAN environments, including traffic segmentation, deterministic forwarding, fast recovery and quantum-safe encryption. These platforms should emphasize reliability and offer the flexibility to adapt to future OT networking requirements.

Resilient, high-capacity optical transport

At the optical transport layer, utilities should seek out solutions that can deliver high capacity, low latency and fast recovery across a variety of topologies over long distances. It’s also important to choose solutions that ensure high operational visibility and resilience over any reach. The ideal optical platforms will allow utilities to modernize their WANs with minimal operational disruption and ensure that all their services can coexist.

Automated network management

Automated management capabilities are essential for modern OT networks. Utilities can simplify their operations with solutions that let them automate the management of IP/MPLS, Ethernet, optical and microwave networks and services. Capabilities such as proactive service assurance and multivendor support will help them optimize OT communications and simplify their operations.

Utility-specific WAN frameworks

Utilities will benefit from solutions that provide WAN architecture frameworks for interconnecting grid assets, substations, control centers and more. These architectures should address OT availability, performance and recovery requirements.

Expert services

It can be difficult for utilities to navigate the technical, regulatory and procurement hurdles involved in migrating to new mission-critical IP/MPLS and optical WANs. They should look for vendors that have proven knowledge in these areas and offer expert-led services for elements such as network design, security, integration, migration, deployment, optimization, training and support. 

Evolving OT WANs for the new energy future

It’s time for mission-critical OT networks to emerge of the shadows and take their place as key strategic assets for power utilities. As utilities modernize their grid operations, they will depend on WANs to support their OT systems with consistent, predictable performance, high availability and a strong cyber defense. 

Utility WANs also need to support new AI data centers, which require dedicated power infrastructure and integration with the power grid. These data centers will have dynamic, rapidly changing power demands. Utilities must support them with network technologies that can adapt to their needs while delivering resilient and secure communications services.

Nokia uses the latest advances in IP routing, MPLS transport, optical networking and automation to help utilities build resilient WANs that meet the tough requirements of modern OT environments. These networks enable utilities to keep pace with new energy demands making their operations simpler and more efficient, maintaining compliance and protecting their grids from increasingly potent threats.

Find out more

Read the IDC Spotlight to learn more about how Nokia helps utilities meet the reliability, performance and security demands of mission-critical OT.