Data transmission path including a device for checking the data integrity

Described is a data transmission path including a device for checking the data integrity of data transmitted from the sender side to the receiver side of the data transmission path, in a motor vehicle in particular, having a first data modification device on the sender side and a second data modification device on the receiver side which each have the same transmission function and a comparator for comparing the output data of the data modification devices. Input data are modified into output data on the sender side and transmitted to the receiver side, and identical input data are transmitted to the receiver side and modified there into output data. Moreover, a method for checking the data integrity is described.