Serial Device Servers and Industrial Gateways: Bridging Legacy Systems with Modern Connectivity

In today’s fast-paced industrial world, seamless communication between machines, networks, and software platforms is essential for efficient operations. As factories modernise and Industrial Internet of Things (IIoT) solutions continue to expand, organisations face a major challenge: how to integrate older serial-based equipment with modern Ethernet and wireless networks. This is where serial device server and industrial gateways play a crucial role. They act as bridges, enabling smooth data exchange between legacy hardware and advanced digital ecosystems.

What Is a Serial Device Server?

A serial device server, sometimes known as a serial-to-Ethernet converter, is a networking device designed to connect serial-based equipment to IP networks. Many industrial machines still rely on interfaces like RS-232, RS-422, or RS-485. Despite being decades old, these systems remain widely used due to their reliability, simplicity, and long operational lifespan.

A serial device server converts serial data into Ethernet packets, enabling the device to be monitored, controlled, or accessed over a local network—or even remotely via the internet. This eliminates the need for manual connections or outdated communication methods.

Key Functions of a Serial Device Server

• Protocol conversion from serial formats to TCP/IP.
  
  

• Remote access to equipment through a virtual COM port.
  
  

• Data logging and monitoring for accurate machine output.
  
  

• Secure connectivity with modern authentication and encryption.
  
  

• Device management through web-based interfaces.
  
  

For companies relying on legacy serial devices—such as PLCs, barcode scanners, medical equipment, environmental sensors, or CNC machines—serial device servers offer an effective path to network integration without replacing existing hardware.

Understanding Industrial Gateways

An industrial gateway is a more advanced device that connects various communication protocols, networks, or data layers within an industrial environment. It acts as a translator and manager, ensuring seamless communication between different systems.

Where serial device servers mainly focus on converting serial data to Ethernet, industrial gateways offer broader capabilities such as protocol bridging, edge computing, cloud connectivity, and real-time data processing. They support a wide range of industrial communication protocols including Modbus, OPC UA, PROFINET, EtherNet/IP, MQTT, and more.

What Makes an Industrial Gateway Essential?

Industrial gateways help organisations:

• Connect legacy machinery to IIoT platforms.
  
  

• Enable communication between incompatible systems.
  
  

• Enhance operational visibility through real-time data analytics.
  
  

• Improve automation and control processes.
  
  

• Strengthen cyber-security through network segmentation and secure tunnelling.
  
  

Gateways are commonly deployed in smart factories, energy systems, oil and gas facilities, transportation networks, and remote industrial sites.

Serial Device Server vs Industrial Gateway: Key Differences

Although both devices connect equipment within industrial networks, their purposes differ.

1. Functionality

• Serial Device Server: Primarily converts serial communication to Ethernet.
  
  

• Industrial Gateway: Handles multiple protocol conversions, data processing, and cloud integration.
  
  

2. Complexity

• Serial Device Server: Simpler, used for basic connectivity.
  
  

• Industrial Gateway: Supports advanced automation, security, and analytics.
  
  

3. Use Cases

• Serial Device Server: Ideal for connecting barcode scanners, legacy PLCs, laboratory instruments, and other serial-only equipment.
  
  

• Industrial Gateway: Best for large-scale automation systems, monitoring networks, industrial IoT, and smart manufacturing environments.
  
  

Benefits of Using Serial Device Servers

Affordable Modernisation

Integrating serial devices with modern networks avoids costly hardware replacement. Many industries operate machines that still function perfectly, making network upgrades a smarter long-term investment.

Remote Access and Control

Machine data can be accessed from anywhere, simplifying maintenance and troubleshooting. Engineers no longer need to be physically present to manage equipment.

Improved Data Accuracy

Automatically capturing and transmitting data reduces the risk of manual entry errors, improving reporting and operational decisions.

Enhanced Security

Today’s serial device servers include encryption, firewalls, and secure protocols, ensuring data transmission remains protected.

Advantages of Industrial Gateways

Seamless IIoT Connectivity

Industrial gateway connect machines directly to cloud platforms and SCADA systems. They enable real-time monitoring, predictive maintenance, and automated alerts.

Edge Computing Capabilities

Many gateways process data at the edge, reducing latency and bandwidth consumption. This is critical for time-sensitive operations like robotics and real-time quality control.

Protocol Bridging

Industrial environments often use multiple communication standards. Gateways eliminate compatibility issues by translating protocols automatically.

Centralised Device Management

Gateways simplify updates, configuration, and troubleshooting through unified dashboards.

Operational Efficiency

With continuous data flow and analytics, organisations gain valuable insights to optimise production, reduce downtime, and improve overall efficiency.

Common Industrial Applications

Manufacturing

Serial device servers keep legacy machines running while enabling data integration into modern MES or ERP systems. Gateways help synchronise production lines, sensors, and controllers.

Energy and Utilities

In energy plants, gateways enable smart grid communication and real-time monitoring of transformers, meters, and power systems.

Transportation

Rail networks and intelligent transport systems rely on gateways to connect signalling equipment and monitoring devices.

Oil and Gas

Remote sites use gateways for SCADA connectivity, asset tracking, and remote equipment monitoring.

Healthcare and Laboratories

Serial device servers allow legacy medical instruments to communicate with digital records and hospital systems.

Choosing the Right Device for Your Needs

When deciding between a serial device server and an industrial gateway, businesses should consider:

• Type of devices in use (serial-based or multi-protocol)
  
  

• Network infrastructure
  
  

• Need for cloud integration
  
  

• Required data processing capabilities
  
  

• Budget and scalability
  
  

• Security standards
  
  

For simple serial connectivity, a serial device server is more than enough. For large-scale automation and IIoT integration, an industrial gateway provides broader functionality and long-term flexibility.

Conclusion

Serial device servers and industrial gateways are essential components in today’s industrial connectivity landscape. While serial device servers offer an efficient way to modernise legacy systems, industrial gateways enable deeper integration, smarter operations, and advanced automation. Together, they help organisations transition smoothly into the era of Industry 4.0, where data, connectivity, and intelligent decision-making are key to achieving operational success.