Feature: Communications
Time-sensitive networking at the
heart of future industrial networks By Walter Hagner, Product Sales Manager Digital, and David Werthwein, Product Manager Digital, Rutronik
I
ndustry 4.0 and beyond will enable greater automation, making processing and manufacturing operations more efficient, with better quality products, reduced downtime and
safer working environments. But for Industry 4.0 to function to its maximum potential, it needs a constant stream of operational data, provided in the right way – and it is here that time-sensitive networking (TSN) will play a vital role. Low-latency operation will be crucial
to industrial connectivity, allowing equipment and devices to work in sync, with real-time responsiveness for fast and efficient operation.
Active migration There is a migration underway that will see outdated fieldbus implementations – such as Profinet and ControlNet – replaced by Industrial Ethernet. Fieldbus protocols can only support relatively limited data rates – 100Mbit/s or less – far too slow for next-generation
34 June 2021
www.electronicsworld.co.uk
industrial networks, especially if high- definition video streams are required. Furthermore, fieldbus infrastructure deployment is at best piecemeal (which restricts the scope for interoperability between different systems) and very costly. In contrast, Industrial Ethernet is an all-encompassing connectivity platform which is cheap, very robust and capable of supporting much higher data rates than its fieldbus counterparts. The appeal of Industrial Ethernet
is great, but we mustn’t forget there are also certain shortfalls. Whereas fieldbus protocols support deterministic operation, Industrial Ethernet doesn’t. This is where TSN comes in. For Industrial Ethernet to provide
the low latency and assured bandwidth that Industry 4.0 requires, the IEEE has added these TSN standards: 802.1AS, which allows all network nodes to share the same reference clock through timestamping, for synchronisation; 802.1Qbu, which deals with frame pre-emption; and 802.1Qbv, assigned
to traffic prioritisation and scheduling duties. TSN defines a maximum acceptable response time for any given data packet. TSN will allow new industrial
communication infrastructure, based on Industrial Ethernet, to be implemented throughout production and processing sites, while supporting deterministic operation. It will also allow the interfacing of legacy field- bus infrastructure on the factory floor with enterprise-grade Ethernet at the back end (where analysis is performed) without losing the determinism.
TSN ICs There are already several ICs on the market for TSN-enabled industrial networking. The Toshiba TC9562 bridging IC (Figure 1) runs at a speed of 187MHz. Using ARM Cortex-M3 processing, it offloads a workload from the host CPU. Thanks to its advanced Ethernet MAC, it is fully compliant with the 802.1AS, 802.1Qbv and 802.1Qbu
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46
