Hybrid automotive in-vehicle networks

The design of automotive in-vehicle networks is influenced by several factors like bandwidth, real-time properties, reliability and cost. This has led to a number of protocols and communication standards like CAN, MOST, FlexRay and more recently the use of Ethernet. In the future, wireless in-vehicle communication might also become a possibility. In all of these cases, often hybrid schemes such as the combination of time-triggered (TT) and event-triggered (ET) paradigms have been considered to be useful. Thus, hybrid protocols like FlexRay and TTEthernet, offering advantages of TT and ET communications, are becoming more popular. However, until now the hybrid nature of the protocols has not been exploited in application design. In this paper, we will discuss design strategies for automotive control applications that exploit the hybrid nature of the underlying communication architecture on which they are mapped. Towards this, we will consider a mix of time- and event-triggered schemes as well as a combination of reliable and unreliable communication. Correspondingly, we will show how appropriate abstractions of these hybrid schemes could be lifted to the application design stage.