Deterministic and Stochastic Performance Analysis for Real-Time Avionics Networks

Abstract

With the emergence of the new generation of avionics systems characterized by more complex architectures and much richer functionalities, traditional avionics networks can no longer supply comprehensive interactions between avionics sub- systems. The AFDX (Avionic Full Duplex Switched Ethernet) is recognized as one of the appropriate solutions allowing bridging this gap. As a real-time network, the AFDX is sensitive to data transmission delay. Hence, reliability assessment represents an important issue in the design of such networks. In this paper, the AFDX protocol with SP-FIFO scheduling policy is modeled based on the theory of network calculus. A worst case upper bound on deterministic delay is obtained. Moreover, the delay distribution is modeled and a probabilistic delay upper bound is computed using the stochastic network calculus. Experiments are carried out for both deterministic and probabilistic cases and the results conformed the validity of the approaches developed in the present work.