Lars Völker

Challenges in a future IP/ethernet-based in-car network for real-time applications

In current vehicles, a large number of control units are connected by several automotive specific communication buses, facilitating innovative distributed applications. At the same time, computers and entertainment devices use IP and commodity communications technology like Ethernet to connect to the Internet, allowing for innovative solutions and maintaining fast innovation cycles. Today, one can see first applications of Ethernet for in-vehicle communication in contemporary cars. In next generation vehicles, many innovative applications could benefit from the increased bandwidth Ethernet can offer. Therefore, a examination of Ethernet usage for additional in-vehicle communication use cases is needed. In this paper, we show simulation results of promising use cases for in-car Ethernet, while looking at different realistic topologies, types of traffic, and configurations.

IEEE 802.1AS time synchronization in a switched Ethernet based in-car network

As of today Ethernet is used in the in-vehicle network mainly for two use cases: connectivity between the head unit and the rear seat entertainment (RSE) as well as faster onboard diagnostics (OBD). With the increasing bandwidth demand in driver assistance and the wish to easier interconnect the driver assistance and infotainment domains additional usage of Ethernet in the vehicle is being examined. The legacy Ethernet does only provide very limited Quality-of-Service (QoS) mechanisms so that demanding real-time in-vehicle applications cannot meet their constraints. The Audio/Video Bridging (AVB) group introduced several IEEE standards to allow audio and video applications with high QoS demands in a switched Ethernet network. Although these mechanisms were not designed for automotive use cases, they are good extensions to switched Ethernet when QoS demands exist. Therefore, an evaluation of AVB for the usage in in-vehicle networks is needed. In this work, we focus on a base mechanism of the IEEE 802.1 AVB standard, the IEEE 802.1AS time synchronization protocol and its usage in the in-vehicle network. The evaluation is performed by simulation with the network simulation tool OMNeT++ and we modifed the INET-framework with the IEEE 802.1AS capability for our purpose.

Performance evaluation of the inter-domain communication in a switched Ethernet based in-car network

Todays premium vehicles are some of the most complex consumer goods-featuring a large number of different functionalities. These functionalities are being implemented by numerous Electronic Control Units (ECUs), which are often interconnected with CAN, FlexRay, LIN, and MOST. However, some car models already use Ethernet for high bandwidth applications, like diagnosis, flash update, and multimedia applications. With the increasing number of Advanced Driver Assistance Systems (ADAS) the network architecture of the vehicle needs to change in order to keep up with the growing demands. In this paper we focus on a domain-based evolution of todays in-vehicle network using switched Ethernet to keep up with ADAS demands. We examine different suitable Ethernet-based topologies and evaluate them based on realistic in-vehicle traffic in different network load situations. In addition, we determine the impact of MAC-Layer prioritization to the provided in-car applications and to the communication between the in-car domains.