In power utilities, network monitoring is inseparable from operational risk. As OT communication networks expand across substations, transmission systems, and protection environments, legacy SNMP-based platforms increasingly struggle to keep pace with modern grid requirements. Tools such as CastleRock SNMPc, long valued for their reliability in device-level supervision, were not designed for today’s large-scale, multivendor OT architectures.

 They lack the deep observability required for real-time operational correlation or the ability to map physical hardware to the mission-critical services they support. This case describes how a large Asian power utility migrated from CastleRock SNMPc to SGRwin to regain operational visibility and control over substations, transmission lines, and OT communication networks, while maintaining full service continuity throughout the transition.

Why legacy SNMP monitoring becomes a limitation in modern power grids

CastleRock SNMPc continued to deliver basic SNMP-based monitoring focused on individual network elements. However, as OT and IT communication networks expanded in scope, criticality, and geographical distribution, element-level visibility proved insufficient to support resilient and secure grid operations. Utilities increasingly needed to understand how communication failures propagated across substations, protection systems, and electrical assets—a level of observability that traditional SNMP monitoring tools were not designed to provide.

From a NIS2-aligned cybersecurity perspective, legacy SNMP monitoring exposed structural limitations. The absence of topology-aware context and service-level correlation restricted the ability to detect anomalous behavior, lateral movement, and cascading failures within OT communication networks—capabilities central to continuous risk monitoring and incident detection under modern regulatory frameworks.

The most significant challenges included limited scalability across large multivendor environments, weak correlation between communication alarms and electrical impact, static network models that failed to reflect real service paths, and a growing operational dependence on manual configuration. At this stage, the monitoring platform was no longer aligned with the operational, cybersecurity, or regulatory reality of a national power network.

SNMPc migration objectives aligned with OT operational reality

Rather than pursuing a feature-driven replacement, the utility defined the SNMPc migration around operational workflows specific to power networks. The objective was not simply to replace CastleRock SNMPc, but to adopt a monitoring platform capable of evolving alongside grid complexity through enhanced observability.

The utility prioritized multivendor orchestration to unify a disparate landscape of SIAE, Huawei, Ceragon, DIMAT, Cisco, and Fortinet hardware into a single, observable pane of glass. This consolidated view facilitated a shift toward service-centric fault isolation, allowing operators to move beyond generic alerts and identify exactly how a specific link failure in a substation impacts critical protection signaling. Throughout this process, a zero-downtime transition was essential, ensuring the total continuity of mission-critical services while moving operational logic away from the legacy system and into a modern environment.

How SGRwin supports large-scale multivendor OT supervision

SGRwin was deployed as a purpose-built Network Management System for critical infrastructures, acting as a unifying operational layer across OT and IT communication domains. Unlike traditional SNMP tools, the platform enables operators to work with live network behavior and real operational topology rather than static or abstract representations.

In this deployment, SGRwin provided real-time visibility across substations and communication paths, native multivendor modeling without proprietary lock-in, and integrated IT and OT supervision within a single operational context. Alarm correlation was performed with network and service context, allowing engineering teams to understand not only that an event occurred, but where it originated, how it propagated, and which specific services were affected.

A dynamically synchronized inventory ensured that operational data remained aligned with the actual state of the network, reducing discrepancies between documentation and reality. This shift allowed the utility to move from reactive SNMP-based monitoring toward a scalable and maintainable OT observability model.

Operational outcomes and long-term value

By prioritizing resilience by design, the utility achieved a coherent, end-to-end view of its OT infrastructure that yielded immediate operational dividends. The shift to automated root-cause analysis significantly reduced Mean Time to Repair (MTTR) by enabling faster, more precise fault isolation.

Furthermore, the deep observability provided by the new system simplified the path to future-proof compliance, streamlining the rigorous reporting requirements of NIS2 and other regulatory audits. Ultimately, this new framework established a scalable foundation, allowing the utility to onboard new substations and services with a level of predictability and speed that was previously hindered by manual configuration errors.

Conclusion

The migration from CastleRock SNMPc to SGRwin marks a key step from reactive monitoring to proactive observability. By overcoming the limitations of traditional SNMP, utilities gain the resilience needed to manage the complex, heterogeneous services of the modern grid.

As your legacy tools reach their limit, is your network ready for the future? Let’s explore how to apply this service-aware approach to your specific operating environment.