FRAUD HANDLING METHOD AND FRAUD HANDLING DEVICE

An anomaly handling method in an in-vehicle network includes: transmitting and receiving frames; detecting a frame having an anomaly; and switching, when the anomaly is detected in the detecting (S3002: No), a transmission timing of the frame in which the anomaly is detected (S3004 to S3013). The switching includes changing a switched transmission timing to which the transmission timing is switched, according to predetermined information.