Authentication device for a vehicle

An authentication device for a vehicle, wherein the vehicle has a communications network for conveying communications data, comprising:

• a communications interface which is connectable to the communications network of the vehicle, wherein the communications interface is configured to receive the communications data;
• and
• a processor which is configured to detect a characteristic of the received communications data, wherein the processor is configured to authenticate the communications data based on a comparison of the detected characteristic with a reference characteristic,
• wherein the processor is configured to detect an authenticity of the communications data if the characteristic of the communications data corresponds to the reference characteristic and to detect a missing authenticity of the communications data if the characteristic of the communications data differs from the reference characteristic,
• wherein the processor is configured to send a warning message or an error message, to a security system of the vehicle, in response to the detection of the missing authenticity of the communications data,
• wherein the processor is configured to detect a degree of deviation of the characteristic from the reference characteristic, wherein the processor is configured to send the error message if the degree of the deviation exceeds a first threshold value and to send a warning message if the degree of the deviation falls below the first threshold value and exceeds a second threshold value.

A method for the authentication of communications data in a vehicle, wherein the vehicle has a communications network for conveying the communications data, the method comprising:

• receiving the communications data with a communications interface which is connectable to the communications network of the vehicle;
• detecting, by a processor, a characteristic of the received communications data;
• authenticating the communications data based on a comparison of the detected characteristic with a reference characteristics;
• detecting, by the processor, an authenticity of the communications data if the characteristic of the communications data corresponds to the reference characteristic and to detect a missing authenticity of the communications data if the characteristic of the communications data differs from the reference characteristic;
• and
• sending, by the processor, a warning message or an error message, to a security system of the vehicle, in response to the detection of the missing authenticity of the communications data,
• wherein the processor is configured to detect a degree of the deviation of the characteristic from the reference characteristic, and
• wherein the processor is configured to send the error message if the degree of the deviation exceeds a first threshold value and to send a warning message if the degree of the deviation falls below the first threshold value and exceeds a second threshold value.