Work-in-Progress: Best-Case Response Time Analysis for Ethernet AVB

In the automotive industry, Ethernet is currently being introduced as a viable solution for real-time communication with high bandwidth requirements. In this paper, we present and prove a tight bound for the relative best-case response time of a frame in an Ethernet AVB switch compared to its response time in a schedule without interference. Our analysis is based on the observation that frames in a burst, scheduled using a credit shaping policy, may be scheduled earlier in case of interference than in a schedule without interference. We show how an upper bound on the build up of credit may be used to bound this relative speed-up of frames.