As more devices connect to a network, top companies and consortiums are working to advance tools for TSN through participation in testbeds, plugfests, and interoperability workshops for industrial applications.
Shrikant Acharya, President & CTO, Excelfore and Avnu Alliance Automotive segment member
The Industrial Internet of Things (IIoT) is no longer just a buzzword – recent market reports and projections see the IIoT as a burgeoning opportunity for the industrial automation equipment market. A 2017 report from IHS forecasts the industrial sector as being one-third of the total connected IoT devices by 2020 (Source: IoT Trend Watch) and Grand View Research expects the “global industrial IoT market to be worth $93B USD by 2025.” The numbers vary from report to report, but one thing is certain: the IIoT is set to become one of the largest business and economic opportunities over the next ten years.
A large part of the opportunity of the IIoT lies in its networks (Ethernet, WiFi, Cellular, and so on) – an increased number of devices on the network means that there is a need for greater reliability and interoperability to ensure the timely transfer of information to systems with increasingly complex needs. This includes time synchronization that needs to be managed within tenths of a nanosecond in some specific environments. Leading industrial and transportation companies will demand the same high levels of reliability, security and safety for their control systems within the IoT as is provided today by a multitude of specialized but often proprietary and segregated communication technologies; but these requirements with regards to reliability and security must be addressed in a more connected and open infrastructure, leading to challenges in deployment and diagnosis not seen in this type of system. With more operations seeking streamlined processes that save money and time, network infrastructure improvements are a key step in the development of IIoT solutions. This means that there will be an increasing need for interoperability, efficiency and determinism on the network as new automation capabilities arise. Enter: deterministic Ethernet-based networking with Time Sensitive Networking (TSN).

Converged TSN Ecosystems.
Part of the effort to drive interoperability for IIoT devices involves Avnu Alliance, an industry consortium that creates conformance tools for TSN device testing. In 2016, member National Instruments wrote a piece in Design World on the IIoT and the need for Time Sensitive Networking (TSN) in these increasingly connected networks. Since then, the industrial segment has worked with top companies and its liaisons to advance tools for TSN through participation in TSN testbeds, plugfests, and interoperability workshops for industrial applications.
Testbeds: the Industrial Internet Consortium TSN Testbed
Testing a networks’ capabilities before implementation is key to developing a successful network design – testbeds offer systems designers the chance to see how their devices and networks perform in real-world settings, before they are installed.
The first testbed for TSN, the IIC’s TSN for Flexible Manufacturing testbed, was developed with two major goals – to show TSN’s readiness to accelerate the marketplace and to highlight the business value of adopting open, interoperable standards in automation networks. It stands as a showcase of the value that TSN standards and the ecosystem of manufacturing applications bring to the market, including the ability for IIoT to incorporate high-performance and latency-sensitive applications.

Overview of TSN Testbed Design, Source: Industrial Internet Consortium. tsn testbed design.
IIC member participants include industry leaders like: Analog Devices, Belden/Hirschmann, Bosch Rexroth, B&R, Cisco, Hilscher, Intel, KUKA, National Instruments, OPC Foundation, Renesas Electronics, Schneider Electric, SICK, TTTech and Xilinx – many of whom are also Avnu Alliance members. The work coming out of the TSN Testbed already has an impact on many suppliers and manufacturers who see the technology as a value add for their system structure.
The benefit of the testbed is that it demonstrates real-world industrial use cases leveraging TSN. One such envisioned use case is a setup of two separate large-scale robot and automation control suppliers who are seeking to implement TSN technology to increase interoperable communication between their devices and systems. They will coordinate and manage controllers and the monitoring of the sensor data between robots and the controllers. This coordination requires a combination of receiving highly time-sensitive, synchronized information from sensors and then passing control commands back into the environment to other types of devices on the network. Without TSN, these companies would have to perform this communication with separate proprietary, non-standard networking technologies that may not talk to each other on an IoT network.
Interoperability testing with the IIC TSN Testbed is progressing with hands-on plugfests taking place in the US and Europe over the past two years. As a collaborator of the IIC’s TSN Testbed, Avnu Alliance is helping to ensure the continued enhancements to Ethernet that TSN brings. Avnu is a third party independent organization providing conformance testing for interoperability of TSN and related standards, giving industrial vendors the ability to respond to market demand.
Industry education opportunities, conformance testing and certification
Expanding industry education is a key goal of the membership. Cultivating conversations that lead to the greater participation and implementation of TSN begins at the member and organization level, with members taking an industry leadership approach to education around the benefits of TSN for IIoT networking.
Interoperability workshops with more than 20 leading industrial companies across silicon, infrastructure, and automation demonstrated interoperability of TSN devices. Face-to-face workshops focused on vetting the usage of TSN for flexible manufacturing and working on configuration for these systems. The lessons learned from the ongoing IIC TSN Testbed activities and the results from this workshop contributed to the conformance test development and will continue to feed into standards revisions as necessary.
The OPC Foundation is also involved and is working to provide conformance testing and certification of OPC UA over TSN devices.
Testbeds and plugfests help test for a certain degree of interoperability and allow companies to create real-world systems as an early check for problems, but conformance testing ensures alignment with the standards in a more complete way. Leveraging the work done through these relationships and interoperability workshops helps to create a stronger environment for interoperability. In November 2017, the first set of TSN conformance test plans for time synchronization of industrial devices were made available for test houses to implement.
As the standards and networks continue to evolve, so does the work to define and certify the standard foundation. This eventually will include mechanisms such as frame pre-emption (IEEE 802.1Qbu), redundancy (IEEE 802,1CB & IEEE802.1ASrev), ingress policing (IEEE 802.1Qci), and security.
The conformance testing and certification provided through organizations like Avnu will be critical to provide the needed foundation for interoperable IIoT networks and give industrial vendors a more streamlined vehicle for participation in the TSN ecosystem.
Enabling a faster path to certification
To speed up the path to an interoperable foundation, members have made open source code available for 802.1AS timing and synchronization in the OpenAvnu repository on GitHub. To encourage and enable multiple industry groups, vendors and protocols to share a TSN network, system architecture and requirements for this industrial model have been outlined in a document entitled “Theory of Operation for TSN-enabled Industrial Systems,” which is available for download. This document introduces the fundamental mechanisms needed for a system architecture to build on, including time synchronization, quality of service using scheduled transmission and network configuration and walks through the requirements of several industrial use cases including how to enable and integrate non-TSN technologies where needed.
This document will help designers and engineers in the industry understand the real-world application context and build a TSN network that is configured for multiple vendor and industry groups.
Test tools, testbeds, open-source code, and certification program supports vendors with tools for rapid adoption of the TSN standards, giving system designers and engineers the foundation to make sure they do not architect networks that are outdated before they are even installed.
Avnu Alliance
www.avnu.org
Filed Under: IoT • IIoT • internet of things • Industry 4.0