How Ethernet networks can add health, visibility to industrial applications

Plantwide Ethernet: As the number of devices increase in automation networks, management and issue diagnostics become more challenging for automation and information technology (IT) professionals. A converged network approach and greater cross-team visibility of edge devices create reliable, industrial networks in step with Industrial Internet of Things (IIoT) and big data initiatives. Adding edge intelligence and universal visibility are necessary to remove bottlenecks.

By Ken Kao August 28, 2015

As Ethernet continues to upgrade for industrial networks, companies also seek to deepen the integration between industrial automation systems and enterprise applications. What efficiencies can unfold with assembly fault data analysis occurring in a back-end information technology (IT) process, or what golden business intelligence can be discovered in materials’ waste data linked to material vendor invoicing? Networking flexibility opens business implications in ways upper management cannot ignore, even in 2015. 

IIoT requires Ethernet

Industrial Internet of Things (IIoT) innovations in sensor technology, wireless connectivity, energy harvesting, big data, and cloud computing are part of the seamless exchange of information among devices, systems, and people, paving the way for improved performance, flexibility, and responsiveness throughout the enterprise value chain. This points back to the Ethernet; the industrial Ethernet network needs to deliver the data so big data analytics can deliver results.

Considering the Ethernet requirement for more high-speed processes, as well as more data gathering, factories will need a redundant network; one that easily resolves network issues in the control layer. Radiating out, full network visibility would be implemented to ensure a dependable network to edge devices.

Fortunately, a host of available layer 3 router and layer 2 managed switches can provide core network needs. What about layer 2 unmanaged (edge) switch requirements that must stretch to incorporate such characteristics as port status visibility at the IP address level and employ port quality of service (QoS) to ensure a working model for the enterprise needs as much as the automation network? This is a switch’s role usually reserved for robust, managed switches, but the drawback is that such switches deployed on the edge can be costly and require a lengthy ramp-up time to implement. 

Lower-cost managed switches

On this topic, IHS’s John Morse predicts that "the introduction of lower cost, lower functionality layer 2 switches will economically serve the need of users as networks are expanded to meet the degree of connectivity required to join the industrial IoT revolution." Also in a 2014 report on the market for industrial Ethernet infrastructure components, IHS said: "This trend may, in the longer term, see the demise of the unmanaged switch as the prices converge, much in the way the hub has become all but extinct."

To allow port status visibility for automation and IT software, the layer 2 unmanaged switch acting as the edge switch must support Modbus/TCP and simple network management protocol (SNMP) communications. This allows supervisory control and data acquisition (SCADA), human-machine interface (HMI) software, and IT network management system (NMS) software to monitor the switch device status in real time. 

Ethernet reliability

As more programmable logic controllers (PLCs), input/output (I/O) devices, terminal computers, and HMI become more Ethernet-connected, Ethernet will increasingly require the "always-available" adjective. It becomes an exponential resource drain for automation teams that continue without an update that provides visibility to the network’s edge. As edge devices multiply, and the data gathering functions increase, the personnel needed to check buggy switches would be less available, translating into lost data and lost revenue if the connection serves an automated process.

Greater network visibility expedites troubleshooting for automation and IT teams. Edge switch technology that supports Modbus/TCP and SNMP protocols will be the enabler for this.

In this model of converged networking, teams can work towards resolution of network issues fast.

Data from a factory temperature sensor might be important for the factory engineer for process analysis and for the IT department for cloud cold storage and business process analysis; either team could be enabled to send or receive alerts if data loss becomes apparent. 

Enabling diagnostics

However, the next step is more powerful: Either team can diagnose that there is a disconnected Ethernet line to port 5 of the edge switch I/O input hosting the temperature sensor and inform on the necessary fix. This is made possible with an edge switch that has onboard agents for Modbus/TCP and SNMP protocols. The more intelligent edge switch provides detailed statistical information on each port including speed, linkup counter, count on the multicast packet, count on unicast packet, and count on error. With the edge switch also supporting SNMP it will allow the IT team’s network management system or station software to perform status monitoring in tandem. The fix is employed and data restored at the speed of today’s more business-minded automation networks.

Ethernet network transformations like these will take place to keep up with the growing number of devices and the variety of data demands. An Ethernet network can be easily viewable from the device layer to control layer to the central office.

– Ken Kao is product manager for Advantech’s industrial networking team. Edited by Mark T. Hoske, content manager, CFE Media, Control Engineering,

Key concepts

  • Industrial Internet of Things (IIoT) requires Ethernet.
  • Ethernet visibility and diagnostics are needed for reliability.
  • Smart switches improve reliability.

Consider this

Perhaps smarter switches can add to your Ethernet network intelligence. 

ONLINE extra

Advantech provides more information about its Ethernet switches

See an Ethernet research summary from IHS. 

See links to Ethernet research from Control Engineering and two Advantech Ethernet communications products below.