Data NetworksAutomotive Electronics

Bus Systems

CAN, FlexRay, Ethernet, K-Line, LIN and MOST in use

In addition to access to the vehicle via the diagnostic connector (CAN or K-Line), defined by the legislator, other bus systems have also established themselves as standards in the vehicle. These always focus on special requirements, ranging from inexpensive implementation (e.g. LIN) through high bandwidth (Ethernet) to possible use in security-relevant distributed closed-loop control (FlexRay).

CAN - ISO 11898The CAN bus (Controller Area Network) was introduced to enable the networking of a large number of ECUs. It permits high data rates in diagnostics and flash programming.
LINLIN bus (Local Interconnected Network) enables the inexpensive integration of sensors and actuators in vehicle networks. It creates small subnets.
FlexRayFlexRay was invented at the beginning of this century to be able to implement an appropriate bus system for security-critical applications. It enables deterministic time responses and is designed to be redundant.
MOSTMOST (Media Oriented System Transport) was introduced at the beginning of this century to simplify the integration of infotainment ECUs into the vehicle thanks to its special communication mechanisms and high data rates.
K-Line - ISO 9141In the 1990s, the K-Line was one of the first ways of accessing ECUs in completed vehicles.
SAE J1850The launch of OBD led to standardized access of vehicle networks - something enabled in the US with the help of the J1850 standard.
EthernetWith Ethernet, a standard that has been used successfully for years now in networking is currently being introduced to automotive electronics. In addition to inexpensive components, a major advantage is the extremely high bandwidth - both in onboard communication and in flash programming.