Industrial Ethernet: factory floor apps aided by new deal
If this sounds a bit familiar, there have been predictions for close to two decades that Ethernet soon would dominate process-control and SCADA (Supervisory Control and Data Acquisition) applications in factories. The price of ruggedized Ehternet controllers at 10 and 100 Mbits/sec always was reasonable enough to be considered for SCADA, and in recent years, 1-Gbit controller cards started to be cost-effective. The problem lay in the transition of Layer 2 and 3 protocols. Older networks used simpler control protocols, and those like Softing who developed useful solutions, often priced their licensing too high to make high-volume SCADA a reasonable application.
EtherCAT was developed in the early 2000s by long-time logic controller players like Beckhoff and Hilscher, using elements of Fieldbus physical-layer technology with a slave licensing model adopted from CAN. The idea was to use an Ethernet frame with a master-slave messaging model optimized for real-time process control. While licensing of some aspects of EtherCAT was free, the patent royalty payments were a hindrance to growth. Some developers stuck with real-time network alternatives like Profinet and DeviceNet, though few alternatives to EtherCAT could offer a full Ethernet framing methodology.
Major FPGA players realize the necessity of supporting EtherCAT—Xilinx, for example, has worked with Beckhoff on an IP core for a slave interface. The Altera-Softing pact, however, could broaden acceptance of EtherCAT by lowering the price of a network node. The deal will allow designers to develop a range of products such as sensor interfaces, accelerators, and control logic, all based on one reprogrammable FPGA design with embedded EtherCAT IP.
The role of the EtherCAT Technology Group, an industry association that promotes the protocol, was to work out the logistics so that an FPGA utilizing EtherCAT could be offered to OEMs without up-front licensing costs or per-unit royalty pricing. The protocol stack comes from Softing, but Altera users can download the software stack as part of Altera's Industrial Networking Kit.
The SCADA and factory-floor markets are notoriously conservative in adopting new protocols, so the Altera-Softing-ETG deal does not guarantee an automatic stampede to real-time Ethernet. But it may hasten the inevitable shift from CAN and Fieldbus to Ethernet everywhere.