Optimal scheduling policy for AFDX End-Systems with virtual links of identical bandwidth allocation gap size

摘要

The Avionics Full Duplex Switched Ethernet is a data-link layer protocol meant to guarantee deterministic properties, such as bounded end-to-end delay, to ensure required quality of service for avionics applications. The present work focuses on the latency analysis in transmission at the End-System level of such networks. A scheduling policy for handling a set of virtual links of identical bandwidth allocation gap size is proposed. Network Calculus is applied to the delay upper bound computation from the service curve and the arrival curve of End-System. The tightest output arrival curve corresponding to the optimal policy in terms of aggregate output delays is then obtained. Mathematical analysis shows that prioritizing the virtual links with the slowest request rates results in the tightest delay bound. An illustrative numerical example confirming the validity of the proposed algorithm is provided.