AP-LET: Enabling deterministic Pub/Sub communication in AUTOSAR Adaptive

The automotive software industry is facing a paradigm shift driven by the need to develop more and more advanced functionality distributed on multiple electronic control units. The AUTOSAR Adaptive standard has been designed as a service-oriented architecture on top of a general-purpose operating system to tackle this paradigm shift. Nevertheless, it does not provide means to ensure deterministic communication, as required in safety-related components. This paper studies the integration of the System-Level Logical Execution Time (SL-LET) paradigm in AUTOSAR Adaptive. The key design challenges and requirements to support SLLET in AUTOSAR Adaptive are described, highlighting how to overcome the considerable differences between the AUTOSAR Classic and Adaptive domains. Then, a meta-protocol named AP-LET is presented, together with two concrete instances: one based on high-priority tasks and another leveraging timestamps in the message payload to handle communications and ensure determinism. A complete implementation of both protocols is also described. AP-LET was finally evaluated with a realistic automotive application, showing its feasibility and effectiveness.