OPSWAT is rolling out firmware 4.3.0 for the MetaDefender NetWall Fend 5/15 series, adding new protocol support, deeper troubleshooting visibility, and a set of quality-of-life improvements and bug fixes for one of the industry's most deployed hardware data diodes.
What's New in Firmware 4.3.0
- UDP (User Datagram Protocol) Multicast support, allowing the diode to carry multicast traffic patterns common in industrial monitoring and control environments, where a single data source needs to reach multiple downstream subscribers
- Diode-generated Syslog, giving operators a native, standards-based way to monitor diode health and activity and troubleshoot issues faster, without needing separate tooling
- MQTT (Message Queuing Telemetry Transport) publisher support for Modbus, BACnet, and LON via JSON (JavaScript Object Notation) conversion, so data from these widely used building- and industrial-automation protocols can be converted and published directly to an MQTT broker for downstream analytics, dashboards, or historian systems
Why It Matters for OT and Industrial Network Security
As industrial and critical infrastructure operators push more OT data into IT systems for monitoring and analytics, they need a way to do it without opening a path back into protected networks. Firmware 4.3.0 extends what the Fend 5/15 series can carry and how easily operators can monitor it, while preserving the core guarantee of a data diode: data moves one way, and only one way.
What Are MetaDefender NetWall Fend Diodes?
MetaDefender NetWall Fend diodes are hardware-enforced, unidirectional security gateways built to protect critical infrastructure, industrial control systems (ICS), and operational technology (OT) networks. Unlike firewalls or software-based segmentation, a data diode physically restricts data flow to one direction, making it impossible for traffic to travel back into a protected network.
This makes Fend diodes a common choice for utilities, manufacturing, energy, and other environments where OT (Operational Technology) systems need to share data with IT (Information Technology) networks without exposing themselves to inbound risk. The Fend 5/15 series covers a range of throughput and interface needs, from smaller sensor networks to higher-bandwidth industrial deployments.
Frequently Asked Questions
What is a data diode?
A data diode is a hardware device that enforces one-way data transfer between two networks, typically from a secure OT or ICS network to a less trusted IT network. It physically prevents any data from flowing in the reverse direction.
Does the Fend 5/15 series support MQTT?
Yes. With firmware 4.3.0, the Fend 5/15 series adds MQTT publisher support on the output side with conversion of Modbus, BACnet, and LON data into JSON for publishing to an MQTT broker.
Can Fend diodes generate their own log data?
Yes. Firmware 4.3.0 introduces diode-generated Syslog, giving operators direct visibility into diode activity for troubleshooting.
What is UDP Multicast support used for?
UDP Multicast support lets the diode join and send traffic to a multicast group, which is common in industrial environments where one data source needs to reach several downstream systems at once.
Learn More about MetaDefender NetWall Fend Diodes
