COMMUNICATION SYSTEM, ABNORMALITY DETECTION DEVICE, AND ABNORMALITY DETECTION METHOD

摘要

The present invention provides a communication system, an abnormality detection device, and an abnormality detection method with which it is possible to detect communication-related abnormality such as the falsification of information utilizing a difference in sampling timing among a plurality of communication devices. For a system configuration in which ECUs 3a-3e transmit/receive information via a common communication line, communication-related abnormality is detected by a monitoring device connected to this communication line. Each of the ECUs 3a-3b receives information by performing sampling once with prescribed timing during the transmission period of 1-bit information. However, the plurality of ECUs 3a-3e is permitted to perform sampling with different timing. The monitoring device samples the voltage of the communication line multiple times over a prescribed monitoring period including the fastest timing of sampling and the slowest timing of sampling by the ECUs 3a-3e in the 1-bit information transmission period, and detects abnormality on the basis of the result of multiple times of sampling.