methods and algorithms for generating identical symmetrical cryptographic keys . in a method for generating a symmetrical cryptographic key , a first profile is generated , the first profile comprising a series of data points collected over a first period of time . a start time of the first profile is identified and the first profile divided into a sequence of time - based segments , each time - based segment comprising at least one data point . a first symmetrical cryptographic key is calculated from the sequence of time - based segments , and the first symmetrical cryptographic key is stored for at least one of encrypting and decrypting data in cooperation with a second symmetrical cryptographic key substantially identical to the first symmetrical cryptographic key .