CompTIA SecurityX (CAS-005)Security EngineeringMedium

A large manufacturing company is integrating its operational technology (OT) network with its enterprise IT network to enable predictive maintenance and real-time analytics. The security architect is concerned about the potential for IT-based cyberattacks to propagate into the sensitive OT environment. Which specialized network component is BEST suited to provide a highly secure, unidirectional data flow from the OT network to the IT network, preventing any direct inbound communication to the OT side?

  1. AFirewall
  2. BDemilitarized Zone (DMZ)
  3. CIntrusion Prevention System (IPS)
  4. DData Diode
Show answer & explanation

Correct answer: D. Data Diode

A data diode (or unidirectional gateway) is specifically designed to enforce one-way data flow, physically preventing any data from traversing back into the protected network. This is ideal for OT/ICS environments where absolute separation and prevention of inbound IT traffic is critical.

Why the other options are wrong

  • A. A firewall can filter traffic but still allows bidirectional communication, which carries the risk of misconfiguration or exploitation allowing inbound traffic.
  • B. A DMZ is a buffer network that allows limited, controlled bidirectional communication between internal and external networks, not strict unidirectional flow.
  • C. An IPS detects and prevents intrusions but operates on bidirectional traffic and cannot physically enforce unidirectional flow.

Data Diode (Unidirectional Gateway)

A hardware device that ensures data can only flow in one direction, typically used to provide absolute physical separation and security between networks, such as IT and OT.

  • Physically enforces one-way data flow.
  • Prevents reverse data flow or cyberattacks.
  • Commonly used in critical infrastructure (OT/ICS) and high-security environments.

Memory trick: Data Diode Delivers Dedicated Directional Data.

More Security Engineering questions