- Sector: Electricity Transmission & Critical National Infrastructure (CNI)
- Delivery Scope: Network & Domain Separation, Active Directory, Firewall Segmentation, Substation Readiness Engineering, Managed Service Handover
- Compliance Standards: UK NIS Regulations, Enhanced UK Cyber Assessment Framework (CAF), IEC 62443
- Scale: 100+ Remote Transmission Substations
Project Impact at a Glance
100+
Transmission substations surveyed and upgraded
IEC 62443
Industrial cyber security compliance standard met
Enhanced CAF
Aligned to UK critical infrastructure regulations
Zero Disruption
Continuous energy transmission during delivery
The Challenge: Decoupling Complex OT Networks Across Remote Environments
Our client’s operational technology (OT) systems were historically tied to corporate shared infrastructure. Meeting NIS regulations and the UK Enhanced Cyber Assessment Framework required them to establish an independently governed, highly secure network domain across 100+ substations without interrupting grid power transmission.
- Regulatory Demands: National critical infrastructure requirements dictated segregated identity and network perimeters to prevent lateral intrusion from IT to OT systems
- Remote Physical Environments: Equipment had to be staged and deployed across remote, rugged substation environments
- Continuous Transmission: Power transmission is critical national infrastructure; installation, firewall zoning, and cutover carried a zero-tolerance policy for service interruption
The Solution: Multi-Year Network & Domain Separation Programme
Sword was chosen as strategic delivery partner to design and deploy an independent network and identity domain, implementing strict IEC 62443 zoning and deploying ruggedised equipment across more than 100 transmission sites
Substation Discovery & Physical Audits
Surveyed more than 100 substation environments to evaluate power conditioning, rack space, resilience, and environmental limits
Autonomous Domain & Firewall Zoning
Engineered a greenfield Active Directory and identity framework, deploying firewall micro-segmentation aligned with IEC 62443 to isolate substation assets from corporate domains
Ruggedised Deployment & Managed Handover
Configured, tested, and staged hardened network hardware through a verified supply chain model, producing as-built documentation for ongoing managed service support
Measurable Business Outcomes
Efficiency Gain
Delivered a scalable network architecture aligned with upcoming multi-million-pound capital investment frameworks
Regulatory Compliance
Isolated grid operations behind verified IEC 62443 security boundaries, achieving compliance with NIS and Enhanced UK CAF mandates
User Experience
Completed upgrades across 100+ high-voltage substations with zero disruption to public grid transmission
Future-Proof Scalability
Built greenfield Active Directory and dedicated security perimeters that operate completely independently of group corporate networks
"Sword was appointed as strategic technology partner to lead the design and delivery of a multi-year Network and Domain Separation Programme... applying strict governance and validation processes, with designs reviewed by Technical Design Authority and risk teams."
Head of OT and Cyber, UK TNO
More Information
All hardware is pre-staged, hardened, and tested in controlled workshop environments before dispatch, minimising installation time and failure risk in remote substations
All hardware is pre-staged, hardened, and tested in controlled workshop environments before dispatch, minimising installation time and failure risk in remote substations
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