工业自动化

3 Benefits Time-Sensitive Networking  Brings to Railway Networks

Richard Weatherburn

As demand for mass transit increases in densely populated urban areas, so do passenger demands for more entertainment, on-time delivery and safety. The Industrial Internet of Things (IIoT) and impending technologies like Time-Sensitive Networking (TSN) are making this possible.

TSN is a novel technology, currently in development at the Institute of Electrical and Electronics Engineers (IEEE), that offers an entirely new level of determinism in standard IEEE 802.1 and IEEE 802.3 Ethernet networks. Standardizing Ethernet networks with TSN will deliver an important capability: deterministic, time-critical packet delivery.

 

It represents the next step in the evolution of dependable and standardized automation technology and is certainly the next step in improving railway communication.

 

1. TSN Guarantees Real-Time Delivery

Communication-based train control (CBTC), which uses wireless technologies to continually monitor and control the position of trains, could use TSN to guarantee real-time delivery of critical safety data on Ethernet networks also carrying non-safety related data. Ethernet networks standardized with TSN will support higher data bandwidths and reduce the number of devices required for railway communication. Ultimately, with more information being transmitted across railway Ethernet networks, TSN will ensure that the most critical data is prioritized to assure operations.

 

What does railway communication look like today, without TSN? The process is like a police car and a truck sharing a one-lane road: Imagine that a truck, (which represents non-time-critical information), is driving along a one-lane road and can’t see anybody behind or in front of him on the road. So, he drives the truck onto the next section of the road. But just as the truck enters this section, a police car (representing time-critical information) with emergency lights arrives and wants to overtake the truck to quickly reach an emergency situation further down the road. Sadly, the truck has already turned onto the next section of the one-lane road and cannot move out of the way, causing an unexpected delay to the police car! 


This is what happens to current time-critical messages in standard Ethernet networks without TSN. Because of this, the traditional solution has been to run two Ethernet networks; one for safety critical data (such as CBTC) and one for the rest of the data. For passengers, this often results in a slow internet connection, or no connection at all as priority is given to operational Ethernet networks. Overall, it’s a frustrating experience. For operators, this results in a negative impact to the bottom line as two Ethernet networks need to be deployed, from on board the train, train to ground and trackside.

 

But TSN will change this situation by transforming industrial Ethernet standards for railway communication from “I’ll be there as soon as I can” technology to guaranteed on-time data transfer of high priority information, meaning that a single Ethernet network for all data applications can be deployed with confidence.

 

2. TSN Benefits Both Train Operators and Passengers

What will the benefits be for train operators and passengers? Convenience without sacrificing safety. Specifically, TSN will help rail operators:

  • Increase passenger capacity. Remote control and accurate, real-time data means trains can run more frequently and get passengers where they need to be on time and more reliably.
    • What will the impact be on train operators? Train operators will be able to increase revenue by running more trains on routes with high demand, and save money by running less in areas with lower demand.
    • What will the impact be on passengers? Improved passenger convenience – more trains to choose from during the times they need it most.

  • Improve on-train experience. Today’s rail passenger expects more than transportation from Point A to Point B. Passengers expect reliable, strong Ethernet network connection every time they board.
    • How will TSN impact train operators? TSN will allow operators to install less equipment and reduce the need for separate physical networks all while continuing to give passengers a reliable connection. Most importantly, they can continue to keep critical, operational train data moving at the fastest possible speeds while still being safe.
    • What will the impact be on passengers? In our connected world, every minute is critical for passengers. They want to use their commutes to their fullest, whether that’s checking email on the way to office or verifying any train schedule delays online. TSN will work seamlessly in the background while passengers surf the internet or check the status of their next train without any interruption.

  • Deliver a safe ride. Passengers expect connection and communication in the modern train. Although they might connect their devices to the same Ethernet network you rely on as a rail operator, TSN allows both parties to take comfort in the fact that those communications never get in the way of each other or bog down the Ethernet network during a critical moment – such as activating the brakes when there’s danger on the tracks.
    • What will the impact of TSN be on train operators? Train operators will get a reliable, steady stream of both safety and non-safety information, since the Ethernet network will automatically prioritize the delivery of critical safety information. Trains run safely and on-time without disruption.
    • What will the impact be on passengers? Passengers will be able to stream data to their devices without worrying about downtime or throttling because the operator needs to secure the Ethernet network to run the train.

 


Train control relies on a wireless connection between the ground, the train and the wireless network.

 

3. TSN is already Rooted in Railway Networks

TSN will bring a variety of benefits for railway operators. The advantages it delivers are expected by today’s passengers and implementing the standard will help rail companies meet these demands. Although the standard isn’t available yet, it’s important to understand the implications it will have on the transportation industry and what to consider when it’s time to standardize your Ethernet networks with TSN.

 

Operators should take comfort in the fact that TSN will be easy to add to existing Ethernet infrastructure, and the benefits the technology brings to operators and passengers will revolutionize the standards for industrial control for years to come.

 

Interested in learning more about TSN and how it will impact your operations? Read more in our latest white paper.