10 Things You Need to Know About TSN
Time Sensitive Networking (TSN) isn’t so much a new technology as it is an improvement of an existing networking technology — Ethernet. Ethernet serves its purpose well as a standard for ensuring reliable data transmission across networks. If you send something across an Ethernet network, you can be confident that it will arrive at its destination. The only trouble is that you can’t be sure precisely when it will arrive. For example, data can get caught up in a queue, delaying its arrival. These delays are usually brief and don’t significantly affect operations when all you’re doing is opening a file or printing a document, but these delays make Ethernet impractical for applications that require real-time communications, such as in self-driving cars.
TSN is able to solve this problem by guaranteeing data is delivered at a precise time. This blog will take a look at the key highlights about TSN – everything to know about this exciting technology and its real world applications.
- TSN is Ethernet Plus
- TSN is Backward Compatible with Existing Ethernet
- Timing is Everything
- TSN is Modular
- Configuration is Key
- TSN is Ideal for Automation Applications
- Guaranteed Latency Trumps Low Latency
- TSN Can Help Even if Some Devices Don’t Support It
- TSN Introduces New Security Concerns
- Existing Vendor-Specific Technologies May Benefit
As described above, Ethernet lacks the ability to deliver data at a specific point due to the potential of delay. TSN changes all of that by adding the timely delivery guarantees that were lacking in traditional Ethernet.
TSN continues the Ethernet tradition of remaining backward compatible with older technologies, which is good news for organizations that want to implement TSN on existing Ethernet networks. There is no need to install special gateways or protocol translators to make it work in an existing environment.
TSN is all about tightly synchronizing activities across a network, so timing is crucial, as is reflected in the two most important TSN requirements, time synchronization and real-time scheduling.
TSN isn’t a single standard, it’s a collection of standards. This modularity enable network engineers to choose and implement standards in ways that are most suitable for the network’s intended application.
However, a TSN-capable device doesn’t have to support all TSN standards. Device manufacturers can implement the standards selectively, depending on the use case of the device, but they must declare which standards each device supports.
Although Ethernet is designed to be plug-and-play, TSN is not. To reap the benefits of real-time communications, you must configure TSN devices to carefully coordinate their send and receive operations.
On smaller, static networks manual configuration may be an option. On larger, more complex or more dynamic networks, a mechanism is usually required to automate the configuration process.
TSN is like the central nervous system in the human body, which enables the brain to carefully coordinate all bodily functions and movement often without the need for conscious thought. In a similar fashion, TSN enables timely communication among all sensors, actuators and machinery, so they can coordinate their activities among one another or by way of a central control mechanism.
TSN’s guaranteed timely delivery makes it ideal for automation applications, especially industrial automation and in-vehicle automation (as in self-driving cars). However, its use is not only restricted to automation. It can be beneficial in any application that requires reliable transmission of different priorities of traffic on a single network.
TSN is often described as “low-latency” network communications, but latency is less of an issue than jitter. What’s important in TSN is that specific latencies can be guaranteed to ensure that data is delivered precisely when it’s scheduled to arrive — no sooner and no later. How long it takes for data to travel from point of departure to destination is less of a concern. As long as the latency is predictable and planned for (and not excessive), it’s not a huge issue.
TSN can improve the overall performance of any Ethernet network even if one or more end devices don’t support it. Any network connection between two TSN-compatible devices on a portion of the network may be configured to synchronize the devices and use real-time scheduling and other TSN standards to guarantee latencies between the devices. Although the entire Ethernet network won’t be TSN optimized, it will benefit from more efficient communications over those optimized sections of the network.
Because TSN relies so heavily on time synchronization and scheduling, it introduces unique security concerns. For example, malicious participants on the network might introduce additional data frames or change frame priorities to disruptor delay mission-critical traffic. In fact, security measures themselves might throw off timing by consuming extra CPU cycles necessary for ensuring timely processing of data frames.
Through minor changes in vendor-specific systems, such as in master controllers, TSN can directly interact with vendor-specific, real-time Ethernet solutions. This flexibility enables the use of TSN to improve these systems without having to completely replace them.