- March 21, 2016
By Bill Lydon, Editor
The industrial Ethernet protocols for automation were designed long before serious discussions about the IoT and IIoT. Existing industrial networks will need to transform before users can fully experience the benefits of IIoT implementations. This article highlights my observations related to this transformation.
Bill Lydon’s Automation Perspective
By Bill Lydon, Editor
The industrial Ethernet protocols for automation were designed long before serious discussions about the Internet of Things (IoT) and Industrial Internet of Things (IIoT). With the exception of wireless sensor protocols, the most popular industrial Ethernet-based protocols are built on older networking standards, like IPv4 rather than IPv6. The rapid worldwide adoption of IoT to satisfy personal, commercial, IT, and industrial applications are starting to leverage other transport methods for system communications that are compatible with state-of-the-art Ethernet, cellular, and other wireless communications.
Transformations usually contain a lot of moving parts, induce resistance to change, experience false starts, but at some point lead to clarity. This article highlights my observations related to this transformation.
IIoT Architecture Schools of Thought
There are different schools of thought about the architecture for the Industrial Internet of Things.
Old School - Sensors and actuators should be wired and/or networked to controllers with protocols such as Modbus DeviceNet, Profibus, PROFINET, EtherNet/IP, EtherCAT, and IO-Link. Controllers communicate with other controllers, servers (historians) and HMI’s using these same industrial networking protocols. The servers are data sources used by enterprise systems and they communicate over the standard information technology (IT) network.
Progressive- Sensors and actuators should be wired and/or networked to controllers with protocols such as Modbus DeviceNet, Profibus, PROFINET, EtherNet/IP, EtherCAT, and IO-Link. The controller becomes a data source and communicates information over the standard information technology (IT) network.
IoT- Sensors and actuators communicate with controllers and enterprise systems over standard IT networks. These edge devices are the data source available directly without any layers of other software servers, drivers, and applications.
Hybrid - Sensors and actuators have a wired or wireless industrial field communications port to communicate with controllers and/or control and automation devices. Sensors and actuators also have a wired or wireless Ethernet port for communications with enterprise systems over standard IT networks. These edge devices are the data source available directly for enterprise systems without any layers of other software servers, drivers, and applications.
There are many considerations in these architectural decisions and many concepts are being tried in various test beds and real-world applications.
IEEE Internet of Things (IoT) Initiative
Recognizing the broad scope of IoT, the IEEE (Institute of Electrical and Electronics Engineers) launched a multi-disciplinary, cross-platform Internet of Thing initiative in 2014 that is working as a focal point for the global technical community. Members of the Technical Community are invited to participate in progressing the definitions within the IoT through its collaborative document, Towards a Definition of the Internet of Things.
One IEEE project that directly relates to IoT is IEEE P2413 with the goal to define an architectural framework, addressing descriptions of various IoT domains, definitions of IoT domain abstractions and identification of commonalities between different IoT domains.
Time Sensitive Networking (TSN)
TSN is a group of new IEEE standards to provide deterministic performance within standard Ethernet for a wide range of applications. The goal it so to deliver very low transmission latency and high availability with applications including converged networks with real time Audio/Video Streaming and real-time control streams which are used in automotive or industrial control. TSN utilizes a form of time division multiplexing (TDM) with scheduled traffic and some methods to improve performance. It reminds me of the ControlNet protocol.
A major driving force behind the development of these new TSN standards is the emerging Automotive Ethernet market. Today there are multiple proprietary standards for communication in a car with complex cabling. The wiring harness is the 3rd highest cost component in a car, behind the engine and chassis. Harnesses comprise 50% of the cost of labor for an entire car and are the third heaviest component, behind the chassis and engine. Any technology that reduces this weight directly contributes to fuel economy. It’s worth noting that the core technology used in industrial sensor networks CAN In Automation and DeviceNet were built on the CAN bus technology. The CAN bus was introduced in 1983 at Robert Bosch GmbH for use in automobiles, with the protocol officially released in 1986 at the Society of Automotive Engineers (SAE) congress in Detroit, Michigan.
Also, TSN work is currently being carried out in the AVnu Alliance's that has created an industrial group to define compliance and interoperability requirements for TSN networked elements. The organization notes that adding the new capabilities to Ethernet will require changes to the hardware design of Ethernet MACs and switches as well as new software. Not all of these features will be required for all applications, but the capability to support all of these features will likely be required in future hardware and software.
Rockwell Automation & Kollmorgen
Rockwell Automation & Kollmorgen have joined the AVnu Alliance to support the technology.
In the announcement of membership, Joe Kann, Vice President, Global Business Development, Rockwell Automation, commented, “We continue to evolve our industrial control and information solutions to help customers drive real-time productivity and innovation as they strive toward building a Connected Enterprise.” “By participating in the AVnu Alliance, we plan to share our industry knowledge and work together with other members toward further enhancing standard, IP-based Ethernet for manufacturing.”
Steve Crass, VP North America Industrial Automation and Aerospace & Defense at Kollmorgen commented, “Kollmorgen’s business as a provider of innovative high-speed motion solutions is driven by ever-evolving customer needs for high-performance, multidevice fieldbus options.” “Joining AVnu Alliance is a logical next step for our business and AVnu provides us with a forum that will support open systems architectures for many years to come.”
Time Sensitive Network (TSN) Protocols and possible use in EtherNet/IP Systems was discussed at the 2015 annual ODVA conference. George Ditzel of Schneider Electric and Paul Didier of Cisco System Inc. provided an informative presentation titled, Time Sensitive Network (TSN) Protocols and Use in EtherNet/IP Systems.
MQTT (Message Queuing Telemetry Transport)
Message Queuing Telemetry Transport (MQTT) is a publish/subscribe protocol designed for SCADA and remote networks. It focuses on minimal overhead (2 byte header) and reliable communications and works on standard unmodified Ethernet.
Message Queuing Telemetry Transport (MQTT) is starting to show up in IoT applications such as remote monitoring of sensors and controlling actuators. Amazon Web Services, Inc. (AWS) deploys MQTT in the AWS IoT offering, and it provides secure, bi-directional communication between Internet-connected things (such as sensors, actuators, embedded devices, or smart appliances) and the AWS cloud.
MQTT is an OASIS standard. OASIS is a nonprofit consortium that drives the development, convergence and adoption of open standards for the global information society. OASIS promotes industry consensus and produces worldwide standards for security, Internet of Things, cloud computing, energy, content technologies, emergency management, and other areas. OASIS open standards offer the potential to lower cost, stimulate innovation, grow global markets, and protect the right of free choice of technology. OASIS members broadly represent the marketplace of public and private sector technology leaders, users and influencers. The consortium has more than 5,000 participants representing more than 600 organizations and individual members in more than 65 countries.
Other OASIS standards of note are Advanced Message Queuing Protocol (AMQP) and Open Building Information Exchange (oBIX). AMQP defines secure, reliable and open Internet protocol for handling business messaging that has been deployed by Microsoft and others. oBIX defines XML and Web services-based mechanisms for building control systems enabling mechanical and electrical control systems in buildings to communicate with enterprise applications.
OASIS is distinguished by its transparent governance and operating procedures. Members themselves set the OASIS technical agenda, using a lightweight process expressly designed to promote industry consensus and unite disparate efforts. Completed work is ratified by open ballot. Governance is accountable and unrestricted. Officers of both the OASIS Board of Directors and Technical Advisory Board are chosen by democratic election to serve two-year terms. Consortium leadership is based on individual merit and is not tied to financial contribution, corporate standing, or special appointment.
To a major extend, consumer products have achieved the goal of making technology invisible. However, industrial automation architectures and networking protocols have not conquered the obstacles to achieve this ease-of-use. Today, systems and networks configuration require people with unique knowledge and skill sets. As a point of reference for those that used early PCs think about the difficulty, procedures, and knowledge required to install applications, printers, and networks on your computers. Today, it is very easy to accomplish these tasks without specialized knowledge. The opportunity for the industrial automation industry is to leverage IoT technologies to provide greater value and dramatically simplifying the application of technology to increase manufacturing productivity.
Industrial automation industry has a history of delivering greater value as lower cost Commercial Off-The-Shelf (COTS) technology have been adopted, including operating systems, computers, Ethernet, and standard HMI’s. The use of COTS technology enables more cost-effective systems that can be used for a broader range of applications.
The adoption of IoT COTS technology in industrial automation systems provides the basis for the next big step for broader application of automation in manufacturing.
- Time-Sensitive Networking Task Group
- AVnu Alliance
- ODVA 2015 Annual Meeting Presentation - Time Sensitive Network (TSN) Protocols And use in EtherNet/IP Systems
- Industrial IoT - It’s the technology stupid
- What is an open standard?
- Industrial Automation Industry Absorbed by IT (Information Technology)
- Amazon delivers AWS IoT development platform
- Stimulus for New Automation Architecture
- Will Industry 4.0 & IIoT create new standards wars?
- Ethernet Infrastructure - Is IPv6 another Y2K?
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