Gateway Strategies for Embedding of Automotive CAN-Frames into Ethernet-Packets and Vice Versa

Abstract

Abstract. Today's automotive communication architectures are composed of up to five special purpose communication technologies with dedicated features to interconnect hundreds of comfort-, safety-, and infotainment-related distributed functions. In the future, the number and complexity of such highly distributed functions will further increase and the outcome of this are stronger requirements to the underlying communication architectures. Ethernet and IP, both standardized and widely used in other industrial sectors, could be one solution to handle the upcoming requirements and could homogenize the variety of communication technologies. This paper focuses on a transformation concept to connect a CAN-based network to an Ethernet/IP-based network and vice versa. It highlights several variants which optimize different objectives, like the protocol header overhead or the latency of messages. Moreover, it presents measured results for different network utilizations and a currently deployed automotive CAN subnetwork.

Formal timing analysis of CAN-to-Ethernet gateway strategies in automotive networks

“…Different CAN to Ethernet multiplexing strategies for gateways have been studied by Kern et al (2011), Ayed et al (2011), Scharbarg et al (2005, Nacer et al (2013), and Herber et al (2015). In Kern et al (2011) a prototypical CAN/Ethernet multiplexing gateway has been implemented to generate experimental results for average end-to-end latencies, required network bandwidth, and resource utilization of the gate-way processor for different multiplexing strategies.…”

“…In Kern et al (2011) a prototypical CAN/Ethernet multiplexing gateway has been implemented to generate experimental results for average end-to-end latencies, required network bandwidth, and resource utilization of the gate-way processor for different multiplexing strategies. The authors of Ayed et al (2011) present two simple multiplexing strategies (a 1:1 mapping and a timeout-based strategy) along with a formal analysis and propose an optimization of the timeout value regarding schedulability and gateway resources.…”

“…Based on Kern et al (2011), Ayed et al (2011), Scharbarg et al (2005, Nacer et al (2013), and AUTOSAR (2015), Ethernet frames can be triggered by:…”

“…-Buffer Timeout This time-trigger is specified by a fixed timeout per buffer so that the gateway emits an Ethernet frame periodically (Kern et al 2011;Ayed et al 2011;Scharbarg et al 2005;Nacer et al 2013;AUTOSAR 2015). -Buffer-full Event In case of a lossless buffering strategy, an Ethernet frame is transmitted once the queue is full (Scharbarg et al 2005;Nacer et al 2013;AUTOSAR 2015).…”

“…-Buffer-full Event In case of a lossless buffering strategy, an Ethernet frame is transmitted once the queue is full (Scharbarg et al 2005;Nacer et al 2013;AUTOSAR 2015). -Trigger Frames Incoming CAN frames with particular identifiers immediately trigger the transmission of an Ethernet frame, which corresponds to the AUTOSAR configuration TriggerMode=TRIGGER_ALWAYS (Kern et al 2011;AUTOSAR 2015). -Per-frame Timeout Incoming CAN frames set a timer, which then triggers the transmission of an Ethernet frame, i.e.…”