Data Diodes

Data Diodes ensure unidirectional data traffic between domains. link22 Data Diode Zero is a highly cost-effective product that provides network separation using an internal unidirectional optical fiber.

Security via hardware

Data Diodes are a simple yet powerful tool in cybersecurity, creating segmentation and isolated networks. A physical data diode transmits information using light through a unidirectional optical fiber. Because the diode’s security is based on the physical hardware, free from software vulnerabilities.

Security for critical infrastructure

Data diodes are highly suitable for use with critical infrastructure (OT) and control systems (ICS). The diode provides secure one-way communication where information such as logs, alarms, and historical data can be exported, still with full assurance that no path is opened for attacks in the opposite direction.

Cost effective

Data Diode Zero is likely the most cost-effective hardware diode on the market. It features optical hardware separation that ensures one-way data traffic. Despite its simple design, it is powerful, reliable, and suitable for network segmentation and protecting critical infrastructure.


Our cost-effective Data Diode Zero allows for the use of multiple diodes in the infrastructure without incurring significant costs. These diodes can be employed for network segmentation, unidirectional traffic routing from OT networks to IT networks, safeguarding offline backups, and more.

In many scenarios, a data diode proves to be a superior and more cost-effective solution than a firewall. Moreover, a hardware diode doesn’t require high expertise for configuration.


Data Diode Zero supports one-way data traffic over UDP (User Datagram Protocol).

To provide maximum flexibility, Data Diode Zero is a pure hardware diode that can be supplemented with standalone software to handle more complex protocols and file transfers. This gives the customer maximum flexibility to choose the components that meet the requirements of their specific operations and IT networks. It also provides flexible scalability over time.


Data Diode Zero features a small form factor and an elegant housing made of durable metal. Its compact size allows the diode to be practically attached like an adapter to the network cable.

This form factor makes it suitable for various environments; it can be utilized in office settings, it is convenient for use in server rooms alongside rack-mounted equipment and cabinets.

Details about Data Diode Zero

Data Diode Zero can serve as a one-way bridge, allowing data to flow from an open system into a closed system, for instance, to handle confidential information securely. Once inside the closed system, the information has no way out because the diode’s optics prevent the transmission of data (light) in the opposite direction.

Examples of usage:

  • Importing confidential documents and files.
  • Importing necessary software updates

With Data Diode Zero, information can be transmitted from a closed system to an open system without opening the closed system to receive information. Data export becomes possible while preventing intrusion.


  • Unidirectional traffic flow between Operational Technology (OT) and Information Technology (IT).
  • Export of PLC readings from systems that are part of critical infrastructure.
  • Protection of data sent to a log server.
  • Safer than a firewall
  • Physically unidirectional data traffic via internal fiber optic link.
  • Protocols: Ethernet, UDP.
  • Supplement with separate software from link22 for support of other, higher protocols and file transfer.
  • Speed: Up to 1Gbit/s (UDP)
  • Interface: RJ45/Ethernet in and out
  • No configuration required
  • Dimensions (WxHxD): 6cm x 3cm x 8.1 cm.
  • Weight: 140g.
  • Metal housing.
  • Intended operating temperature: +10°C to +40°C
  • Approval: CE
  • Delivered with AC/DC EU (CE) power supply unit, SWI5-5-E, 90-264V.

link22 also offers data diodes with other form factors for mounting in racks, DIN rails, etc., as part of our Cross Domain Solutions offering. This is done in collaboration with selected partners.

Contact link22 for more information.