Biometric methods for online user authentication

A mobile device comprising:

• a CPU;
• and
• a memory storing instructions for execution by the CPU, wherein execution of the instructions on the CPU implements a method of authenticating a genuine presence of a user, the method comprising:
• generating a probe comprising electromagnetic radiation corresponding to at least two of a water vapor, a carbon dioxide, and an oxygen absorption band, the electromagnetic radiation having a wavelength between 760 nanometers and 2700 nanometers;
• modulating the probe according to a pattern, wherein the pattern is not duplicated when performing a succeeding authentication of the user using the probe;
• directing the modulated probe towards a body part of the user;
• receiving a response of the body part to the modulated probe;
• sending data representing the response of the body part to the modulated probe to a digital data processor;
• and
• at a digital data processor, analyzing the data representing the response of the body part and authenticating the user if the analysis indicates that:
• the data representing the response includes a modulation consistent with the pattern used to modulate the probe;
• and
• a quality of match between spectral characteristics of the data representing the response and spectral characteristics of a class of responses to a probe of the given type for the human body part in a human population exceeds a threshold quality of match, wherein the spectral characteristics of the data representing the response include at least one characteristic attributable to a reflection of the probe by human skin.

An application for a mobile device comprising:

• instructions for execution on a CPU of a mobile device, the instructions being stored on a non-transitory computer-readable storage, wherein the instructions, when processed on the CPU of the mobile device, instruct the mobile device to perform a method of authenticating a genuine presence of a user, the method comprising:
• generating a probe comprising electromagnetic radiation corresponding to at least two of a water vapor, a carbon dioxide, and an oxygen absorption band, the electromagnetic radiation having a wavelength between 760 nanometers and 2700 nanometers;
• modulating the probe according to a pattern, wherein the pattern is not duplicated when performing a succeeding authentication of the user using the probe;
• directing the modulated probe towards a body part of the user;
• receiving a response of the body part to the modulated probe;
• sending data representing the response of the body part to the modulated probe to a digital data processor;
• and
• at a digital data processor, analyzing the data representing the response of the body part and authenticating the user if the analysis indicates that:
• the data representing the response includes a modulation consistent with the pattern used to modulate the probe;
• and
• a quality of match between spectral characteristics of the data representing the response and spectral characteristics of a class of responses to a probe of the given type for the human body part in a human population exceeds a threshold quality of match, wherein the spectral characteristics of the data representing the response include at least one characteristic attributable to a reflection of the probe by human skin.