According to Siemens, TSN (Time-Sensitive Networking) enables even more robust and reliable Ethernet communication between machines and systems, even under high network loads. The company does not regard TSN as a communication protocol, but as a basic technology that extends existing Ethernet mechanisms with QoS (Quality of Service) functions, bandwidth reservation, synchronization, short latency times and bumpless redundancy. "TSN makes it possible to operate several real-time-capable protocols in parallel in a single network," explains Matthias Gaertner, Product Manager in the Digital Factory division at Siemens. "This is a fundamental difference to today's Ethernet-based real-time protocols, where the network only allows a single real-time-capable protocol." TSN is made up of a series of individual standards that only affect the OSI layer 2 of communication. This means that the user interface remains unchanged even with TSN.

In the robotics trade fair model in Hall 9, Stand D35, OPC UA Pub/Sub (Publisher/Subscriber) is used together with TSN for communication between machine controllers. According to Siemens, the reliability of TSN offers decisive advantages for automation, for example in the automotive industry, mechanical engineering and the food and beverage industry. The company's first products with TSN functions - network components, communication processors, software and network management devices - should be available by the end of 2018.

The trade fair model consists of two robots, each of which communicates with a Simatic controller via Profinet and performs synchronized movements. Synchronization between the two controllers takes place via the TSN network with OPC UA Pub/Sub based on TSN. According to Siemens, the pub/sub principle is important here: a publisher, such as a machine controller, places data on the network that is available to all subscribers. The subscribers themselves "decide" whether they need the information. Data transmission in the TSN network is guaranteed via a bandwidth reservation and can be precisely predicted regardless of the load.

The measurement model thus picks up on the advantages of OPC UA with TSN: TSN combines existing standards and optimizes Ethernet through extended QoS mechanisms, time synchronization, low transmission latency and bumpless redundancy. According to Siemens, QoS prioritization in particular offers users with high requirements for reliable communication major advantages: it ensures that applications can meet their respective communication requirements by reserving bandwidth with predictable latency times. The model also demonstrates the coexistence of TSN communication with standard Ethernet communication. For this purpose, data is transferred from the controller to the MindSphere cloud via a communication processor.

According to Siemens, TSN has now reached the necessary technical maturity (including standards). This is demonstrated by the fact that the first corresponding components are available as a hardware basis, which allows Siemens and other manufacturers to expand existing industrial networks with new application options.

The next step with Profinet based on TSN will also be shown to visitors to Hannover Messe 2018 in a live demonstration at the PI (Profibus & Profinet International) stand in Hall 9, Stand D68.