How the Software-Defined Car Can Become a Reality

Two buzzwords are currently dominating the discussion about the further development of automotive electronics: software-defined Vehicle (SDV) and zonal architecture. There is broad agreement in the industry that Automotive Ethernet will play an important role in this vehicle architecture. However, the question of the specific technical implementation is a completely different matter: According to the Ethernet-everywhere principle, should all data connections in the car be based solely on Ethernet in the future? Or will it remain a mixed network architecture in the long term? The whole situation is further complicated by the fact that not only are there a large number of existing transmission technologies, but new solutions are also constantly being developed.

The need for discussion at the 11th Automotive Ethernet Congress in Munich in February was correspondingly high: over 1,200 participants from 27 countries and 46 exhibitors came together in Munich. In his keynote speech, Marcus Wärmer (CARIAD) explained why established OEMs in particular are facing a special challenge. For example, more than 500 different control units are currently still in use throughout the VW Group, while new players on the market can design their vehicle architecture without having to consider legacy systems. In addition, the breadth of the vehicle range in a group with nine differently positioned brands requires enormous flexibility in the scope of functions to be implemented. Nevertheless, Wärmer is certain: “In future, there will only be one scalable tech platform for the entire Volkswagen Group.”

So the goal is clear, but the implementation is challenging. In practice, the integration of video signals into a zonal architecture, for example, is fraught with pitfalls: On the one hand, there are proprietary solutions, but on the other hand there are also intensive efforts by the Automotive SerDes Alliance and the IEEE to develop and implement standardized solutions. Three presentations from BMW, Volvo and Marvell dealt with this topic, but came to different conclusions as to which variant offers the greatest chances of success in which technical form.

The fact that new working groups (Tech Committees, TC) are constantly being set up at the OPEN Alliance shows just how dynamic the development of Automotive Ethernet continues to be. For example, TC18 is working on the Remote Control Protocol (RCP), which is intended to make a significant contribution to centralizing the intelligence of peripheral devices. Specifically, MCUs equipped with their own software for controlling sensors and actuators (power windows, windshield wipers, etc.) are to be replaced by simple bridges and the control intelligence will only run as a virtual ECU on a central computer. This not only saves hardware costs, but also enables more efficient and flexible software solutions. In addition to a dedicated RCP focus at the conference, there were also several proof of concepts for RCP applications on display in the accompanying exhibition. The newly founded TC19, which focuses on the development of software for the management and configuration of automotive Ethernet switches, is also concerned with the topic of switches.

Other key topics at the Automotive Ethernet Congress included the 10 Mbit Ethernet variant 10Base-T1s, time-critical TSN networks, safety and security solutions as well as new developments at PHY and cable level. Accompanying workshops also provided concrete assistance for improved validation processes for TSN-based systems within zonal architectures and for the use of fiber optic connections in multi-gig networks. Technica's SOME/IP Master Class celebrated its premiere at the start of the congress: An entire day was dedicated to the basics and subtleties of service-oriented communication in vehicles. And although this middleware is now an established standard, the many questions from participants proved that there is still a great need for advice on its practical application.

So one thing is already certain: there will once again be plenty to discuss at the next Automotive Ethernet Congress planned for the end of March 2026 in Munich.