1. A method for deriving a cryptographic key for a microelectromechanical sensor (MEMS) device, comprising: determining a first feature vector for a first MEMS device, the first feature vector having a first plurality of values, each of the values in the first plurality corresponding to a first measurement, respectively, of a plurality of different physical properties of the first MEMS device; determining a second feature vector having a second plurality of values, each of the values in the second plurality corresponding to a second measurement, respectively, of the plurality of different physical properties of the first MEMS device or to a first measurement, respectively, of the plurality of different physical properties of a second MEMS device; and deriving the cryptographic key from the first feature vector and the second feature vector using a processor.