Analysis of Acoustic Information Protection Methods in Critical Applications

Abstract

Subject of the study: the process of acoustic information protection in computer systems of critical applications to ensure the required level of system security. The aim of the article is to analyze the methods of acoustic information protection in computer systems of critical application by means of masking to ensure the impossibility of unauthorized access to the system. The article solves the following tasks: to analyze the software and hardware masking of speech; to study the masking of speech messages in order to introduce unrecognizability; to study the features of speech message compression; to investigate methods of covert transmission of acoustic information. The results of the work, which were obtained using mathematical methods of information transformation in computer systems, are potentially possible methods of masking speech messages to ensure the impossibility of unauthorized access to the system. The analysis of the functioning of the presented methods has led to the following conclusions. One of the perspective directions of acoustic information protection in communication channels and dedicated premises can be considered the creation and development of computerized speech masking systems along with or in conjunction with traditional technologies of semantic protection of acoustic information, namely, speech signal classification based on cryptographic algorithms. The main requirements for today's systems that provide protection of acoustic information in critical computer systems are speed and efficiency of various speech signal processing procedures using standard inexpensive technical means of computer telephony, namely: a personal computer, sound card, telephone line interface device and/or modem. These requirements can be met by applying digital methods of dynamic spectral analysis, i.e. synthesis of speech and audio signals. The choice of specific methods and means of speech masking as one of the types of semantic protection of acoustic information will depend on the practical requirements for the speech protection system and the technical characteristics of the acoustic information transmission channel. Further research is desirable to analyze the possible use of methods for synthesizing large ensembles of quasi-orthogonal discrete signals with improved ensemble, structural and correlation properties to ensure higher security indicators of acoustic channels in computer systems of critical applications.