IoT Guide

Industrial IoT Gateway — All-in-One IIoT Gateway | Eziwan

Industrial IoT Gateway: Modbus/RS-485/OPC UA data collection, built-in 4G router, VPN, edge computing. All-in-one solution for IIoT. Guide and comparison.

Quick answer
A industrial IoT gateway is a gateway that collects data from PLCs and sensors (Modbus, RS-485, OPC UA), converts it to MQTT/JSON, and transmits it to the cloud via 4G/Ethernet, while ensuring VPN and OT security.

IoT Gateway vs. Industrial Router: What’s the Difference?

There is often confusion: a modern industrial IoT gateway includes a router, but it is much more than just a piece of networking equipment. Understanding this distinction is essential for choosing the right solution.

CritèreIndustrial RouterIndustrial IoT Gateway
Primary FunctionForwarding IP PacketsCollect, convert, filter, route
Field ProtocolsModbus, RS-485, OPC UA, BACnet, M-Bus
Data ProcessingEdge computing, filtering, aggregation
Cloud ConnectionRaw (IP)Structured MQTT/HTTPS
Industrial VPNOptionnelIncluded by default
4G ConnectivityDepending on the modelBuilt-in (embedded SIM)
Fleet MonitoringBasiqueDedicated cloud console

In summary: If you need to collect data from PLCs and send it to an IoT platform, you need a gateway. If you only need network access between two sites, a router is sufficient.

See also the IoT Gateway page for a general introduction to the concept.

Supported protocols: Modbus, RS-485, OPC UA, BACnet, M-Bus

The primary criterion for selecting an industrial IoT gateway is the list of field protocols it natively supports. Replacing the PLCs to make them compatible would be costly and risky.

Modbus RTU / RS-485 — the most widely used field protocol in the industry, found in virtually all industrial PLCs, drives, meters, and sensors for the past 40 years. The Eziwan gateway queries Modbus registers as a master and publishes them via MQTT.

Modbus TCP — the Ethernet version of Modbus, used on modern industrial local area networks. Compatible with PLCs from Schneider, Siemens, Wago, Phoenix Contact, and most major manufacturers.

OPC UA — the open standard for Industry 4.0, ensuring interoperability across all manufacturers. The gateway acts as an OPC UA client and publishes nodes to the cloud via MQTT.

BACnet — the leading protocol in building management systems (BMS) and HVAC systems. Supports MS/TP (RS-485) and BACnet/IP (Ethernet).

M-Bus — a protocol designed for reading energy meters (water, gas, heat, electricity). Essential for metrology and metering applications.

For a detailed description of each protocol, see our guide Industrial Protocols.

Integrated edge computing: filtering data at the source

Uploading each raw measurement to the cloud every second is economically and technically absurd. An industrial IoT gateway applies processing rules at the source before any data is sent.

Typical edge computing functions:

  • Threshold filtering — send a value only if it exceeds a threshold or varies by more than X%.
  • Time-based aggregation — Calculate the average, minimum, maximum, and standard deviation over a sliding window (1 min, 5 min, 1 h) and send only the result.
  • Anomaly detection — Locally identify abnormal behavior and trigger an immediate alert without waiting for the cloud.
  • Buffering during Outages — Store measurements in local memory during a network outage and resynchronize them upon reconnection, without data loss.
  • Transformation — Convert voltage to temperature, a pulse to volume, or a raw reading to a physical value with units.

Edge computing typically reduces mobile data usage by 70 to 95 percent compared to raw data transmission, which cuts connectivity costs by the same amount.

For more information: Industrial edge computing.

Integrated VPN and OT Security

OT (Operational Technology) networks host controllers that manage physical processes. A security breach can result in property damage, injuries, or production shutdowns. Security is not an option.

The security architecture of the Eziwan industrial IoT gateway is based on several principles:

Zero-trust networking — no incoming ports are open on the gateway. The connection is always initiated from the inside to the cloud via an encrypted VPN tunnel (WireGuard or OpenVPN). Even behind an ISP’s NAT without a static IP address, the gateway remains accessible from the cloud console.

IT/OT Segmentation — The gateway creates a clear boundary between the field network (Modbus, RS-485) and the IP network. PLCs are never directly exposed to the Internet.

Certificate-Based Authentication — Each gateway has a unique certificate signed by the Eziwan authority. No unauthorized gateway can connect to the platform.

Signed OTA Updates — The firmware is cryptographically signed. Any unauthorized update is rejected.

Zero-Touch Provisioning (ZTP): Deployment Without a Technician

Deploying a fleet of 50 gateways across 50 different sites with a network technician at each location costs a fortune. Zero-Touch Provisioning eliminates that cost.

The 4-step Eziwan ZTP process:

  1. Factory Preconfiguration — The gateway ships with a unique identifier and bootstrapping parameters.
  2. Automatic Initial Connection — When powered on, the gateway connects to the Eziwan ZTP server via the embedded SIM.
  3. Configuration download — site name, protocols to query, Modbus addresses, thresholds, VPN, MQTT: everything is deployed automatically.
  4. Operational in Minutes — Only logistics personnel are needed on-site to plug in the equipment.

ZTP is essential for large-scale deployment projects: smart meters, monitoring of a solar farm, and remote meter reading for a water network.

Our Gateway Solutions and Protocols

Every use case has its optimal solution. The table below will direct you to the page that best suits your protocol or need.

NeedSolutionLearn More
All-in-one industrial gatewayEziwan Gateway/gateway
Gateway for Industry 4.0IIoT Gateway/iiot-gateway
IoT Gateway OverviewIoT Gateway/iot-gateway
Modbus RTU Controllers to CloudModbus RTU to Cloud/modbus-rtu-cloud
Modbus TCP Controllers to CloudModbus TCP to Cloud/modbus-tcp-cloud
RS-485 network to 4G/cloudRS-485 Modbus 4G/rs485-modbus-4g
OPC UA Servers to MQTTOPC UA to MQTT/opc-ua-mqtt
BACnet Controllers to CloudBACnet to Cloud/bacnet-cloud
M-Bus Meters to CloudM-Bus to Cloud/m-bus-cloud
Cloud Data Logging and ArchivingIndustrial Cloud Data Logger/industrial-cloud-data-logger
Local Data ProcessingIndustrial Edge Computing/industrial-edge-computing

Frequently Asked Questions

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