PERSPECTIVES OF USING ARTIFICIAL NEURAL NETWORKS WITH MULTILAYER QUANTIZER IN TECHNOLOGY OF BIOMETRIC-NEURAL-NETWORK AUTHENTICANTION
Background. At the present time the problems of personality authentication using biometric data are becoming topical. The advantage of artificial neural networks of large size over classical codes with error detection and correction lies in the fact that in the moment of learning the networks are capable of taking into account real distributions of multidimensional probabilities of biometric data, whereas all the classical codes of error detection and correction are based on the hypothesis of probable distribution of errors. The article is aimed at changing the paradigm of neural network processing; the authors suggest to switch from binary neurons (perceptron) to using neurons with multilayer quantizers. Materials and methods. The comparison is conducted using a complex code quality index - entropy (proximity to "the white noise"). For codes of about 20 bits in length the entropy may be calculated according to Shannon. For longer codes the resources modern machines are insufficient. It is suggested to analyze only the initial part of the code sequence of the increasing length. After that it is necessary to build an extrapolating polynomial and predict the expected long code’s entropy value. Results. The resulting value of 256 bit entropy of codes of the neural network converter turned to be higher than 51-vit entropy of codes of "the fuzzy extractor". The gain is conditioned by the length of the bio-code despite the fact that long codes have a higher level of correlation of their positions. The transition from binary neurons to neurons with multilevel quantizers increases the gain to up to million times. Conclusions. In the course of transition from binary neurons to ternary neurons the length of the output code increases two times, and their entropy increases appoximately 1,5 times. The gain relating to the increase of biocode entropy increases with the number of quantization levels in each neuron. At the same time the problems of neural network learning also become complicated. It is necessary to modify the standard algorithm of learning ГОСТ Р 52633.5-2011 for networks consisting of the combination of regular binary neurons and ternary neurons.