By: Scott Coleman, VP, Product Management, Owl Cyber Defense
Industrial control systems are just as vital to government programs and operations as they are to traditional critical infrastructure operators (power, telecom, utilities, etc.). These systems, which govern essential processes such as water distribution, power generation, and facility automation across geographically dispersed sites, are more susceptible to cyber threats due to legacy infrastructure, complex supply chains, and inadequate IT-based cyber protection that doesn’t meet the needs of Operations Technology (OT) and stringent compliance requirements.
Reducing the attack surface through proven hardware-based solutions has become a best practice for protecting OT environments. Data diodes, which enable secure, hardware-enforced data transfers across security domains, are a vital component of a multi-layered security strategy aimed at reducing attack surfaces.
Data Diodes as a Cornerstone of Industrial Control Systems (ICS) Defense
By physically blocking any return traffic, a data diode eliminates opportunities for external attackers to infiltrate the network, issue malicious commands, or install malware on critical operational technology (OT) for data flows routed over a data diode This form of physical enforcement is a key advantage over software-only solutions, which can be bypassed or misconfigured.
The National Institute of Standards and Technology (NIST), National Cross Domain Strategy and Management Office (NCDSMO), and Cybersecurity and Infrastructure Security Agency (CISA) continue to highlight the importance of layering data diodes into a defensive strategy alongside perimeter controls, comprehensive monitoring, and incident response.
- NIST SP 800-82 Revision 3, Guide to Operational Technology (OT) Security, details how unidirectional gateways fit into a layered defense approach for high-risk environments.
- NIST SP 800-53 Revision 5, Security and Privacy Controls for Information Systems and Organizations, provides comprehensive controls for boundary protection (SC-7) and information flow enforcement (AC-4) that align with hardware-based one-way solutions.
- Through ICS-CERT, CISA frequently endorses data diodes in its recommended practices, highlighting their value in isolating critical networks.
- NCDSMO also reinforces hardware-based unidirectional data transfer solutions for high-security or cross-domain scenarios.
Aligned with this guidance and building on a 25+ year pedigree in secure data transfer solutions, Owl Cyber Defense’s Owl Talon Data Diode Platform enforces secure one-way transfers while maintaining two-way communications on both the source and destination networks. This design ensures a secure unidirectional data transfer while maintaining standard two-way network exchanges, supporting flow control, protocol handshakes, and acknowledgments while preserving the benefits of a strictly enforced one-way flow.
Defense in Depth for Optimal Resilience
While data diodes are an essential component of a successful defensive posture, true protection against today’s cyber threats requires multiple security layers—a concept known as defense in depth. Defense in depth prescribes different security measures for different use cases while also layering defensive measures to increase overall effectiveness Owl Cyber Defense’s data diodes have been integral to numerous defense-in-depth architectures, safeguarding continuous operations, mission-critical processes, and strict availability requirements.
For U.S. government agencies, securing ICS with data diodes remains one of the most robust strategies for mitigating threats, especially in high-risk or geographically dispersed environments. For example, a ransomware attack on a municipal water treatment facility originated from a phishing email, allowing attackers to breach the IT network and spread into the ICS, disrupting water quality monitoring and chemical dosing controls. If a data diode had been in place, it would have blocked the attack from reaching the ICS while still allowing operational data to flow outward for monitoring. By physically enforcing one-way data flow, data diodes significantly lower the likelihood of remote tampering or malicious updates while enabling essential operational data to move outbound. ICS environments should view data diodes as a key element of their defense-in-depth cybersecurity architecture, helping to counter advanced threats, protect vital operational systems, and ensure the continuity and safety of government missions.
Explore the latest release of the Owl Talon Data Diode Platform, featuring expanded protocol support, broader COTS compatibility, and more.