Worst-case deadline failure probability in real-time applications distributed over controller area network

Real-time applications distributed over the controller area network (CAN) a re generally characterised by stringent temporal and dependability constrai nts. Our goal is to take account of transmission errors in the design of su ch applications because the consequences of such disturbances are potential ly disastrous. In this study, the concept of worst-case deadline failure pr obability (WCDFP) is introduced. The motivation of the probabilistic approa ch is that, in practice, the number of errors occurring during a given time period can with difficulty be bounded. To evaluate the WCDFP, we propose, on the one hand, a method of computing for each message the tolerable thres hold of transmission errors under which timing constraints are guaranteed t o be met. On the other hand, we also suggest an error model enabling us to consider both error frequency and error gravity. Our error model follows a generalized Poisson process and its stochastic parameters have been derived . We then propose a numerically efficient algorithm to compute the probabil ities and apply the analysis to an industrial case-study of the automotive field. (C) 2000 Elsevier Science B.V. All rights reserved.