I’ve just purchased a small development board and investigating the processor on that board, the company that makes it is replacing it with a newer model. It gave me an opportunity to look at their latest model which features TSN, a technology which will revolutionise industrial practices for companies that rely on Real Time Systems.
What is TSN?
Time Sensitive Networking is used by Real Time Systems which are systems that rely on actions to be performed at the right time.
Take a conveyor belt at a food company packing jam, the belt moves the jar under the heater to heat the jar with steam then the jam is added, then the label is attached followed by the lid which is screwed shut and the tamper sticker is added. Everything has to happen when the jar is in the right place on the belt.
A traditional desktop computers run multiple tasks at the same time because the operating system swaps the tasks in and out of the processor and memory as required. If there is an activity like saving something to a hard drive, then the operating system stops everything else while the task of writing to the hard drive completes.
If factories used computers to control the jam line, then the jam would miss the pot or the label wouldn’t stick right.
Industries that rely on Real Time Systems tend to use dedicated networking systems known as FieldBus which only a select few manufacturers sell, at a premium and that limits which platforms can run on FieldBus.
What does TSN do differently?
TSN uses standard protocols to move data using Ethernet connections instead of using proprietary protocols and a system called FieldBus.
By using off the shelf components and drivers, the cost of manufacturing Real Time Systems can be reduced considerably. All devices on the network communicate with the same time through something called PTP or Precision Time Protocol, which keeps everything on the network to precisely the same time and uses Real Time Shaping to mould the traffic on the network so the time critical activities get a higher priority (known as IEEEQbv TAS or Time Aware Shaping)
