Today acutely raises the issue of providing information confidentiality in conditions of growth quantity and quality of violations in cyberspace that are constantly improving and developing. Reliability of traditional methods for ensuring confidentiality is questionable taking into account contemporary threats. So look for alternative methods and means of security is urgent issue. Significant interest causes quantum cryptography, which do not depend on computing or other capabilities of offender, uses specific unique properties of quantum particles, and based on the inviolability of the laws of quantum physics. One of the most advanced technology of quantum cryptog-raphy is quantum secure direct communication, which can transmit information directly by open channel (without encryption – in this case there is no key distribution problem), but they have only asymptotic resistance to noncoherent attacks and, certainly requires some methods for amplification security. In this regard, developed a method of ensuring the stability of quantum cryptography protocols. To evaluate the effectiveness of this method was developed a methodology for conducting experimental research, according to which it is made comparing of its performance with known method. According to the obtained results, the proposed method has a speed in 1.52 times faster against analogs at the same level of resistance to noncoherent attacks.
Today acutely raises the issue of providing information confidentiality in conditions of growth quantity and quality of violations in cyberspace that are constantly improving and developing. Reliability of traditional methods for ensuring confidentiality is questionable taking into account contemporary threats. So look for alternative methods and means of security is urgent issue. Significant interest causes quantum cryptography, which do not depend on computing or other capabilities of offender, uses specific unique properties of quantum particles, and based on the inviolability of the laws of quantum physics. One of the most advanced technology of quantum cryptog-raphy is quantum secure direct communication, which can transmit information directly by open channel (without encryption – in this case there is no key distribution problem), but they have only asymptotic resistance to noncoherent attacks and, certainly requires some methods for amplification security. In this regard, developed a method of ensuring the stability of quantum cryptography protocols. To evaluate the effectiveness of this method was developed a methodology for conducting experimental research, according to which it is made comparing of its performance with known method. According to the obtained results, the proposed method has a speed in 1.52 times faster against analogs at the same level of resistance to noncoherent attacks.
With the measureless, huge and rapid data exchange in network environments and increasing the attackers capabilities, quantity and quality of violations in cyberspace, information security has become the most important process for data storage and communication. Reliability of traditional methods for ensuring confidentiality is questionable, taking into account contemporary threats. Thereby, search of alternative methods and means for security is urgent issue. Significant interest causes quantum cryptography, which do not depend on computing or other capabilities of intruder, uses specific unique properties of quantum particles, and based on the inviolability of quantum physics laws. One of the most advanced quantum cryptography technology is quantum secure direct communication, which can transmit information directly by open channel, but it has only asymptotic security to non-coherent attacks and, certainly requires some methods for security amplification. In this regard, high- speed privaсy amplification method for quantum cryptography protocols was developed. To evaluate the effectiveness of this method was developed a methodology for experimental research, under which comparing of its performance with known method was made. According to the obtained results, the proposed method has a speed faster against analogs at the same level of security against non-coherent attacks.
In the last few years, development of quantum cryptography has attracted the scientist’s attention. Researches passed from the theoretical level to introduction of ready commercial decisions. The main difference between the methods of quantum cryptography and traditional (symmetric and asymmetric) cryptography consists in use of absolutely different principles in the basis. The quantum cryptography does not depend on computing or other intruder opportunities, uses specific unique quantum particles properties and based on inviolability of quantum physics laws. Among the most developed technologies of quantum cryptography is worth noting quantum secure direct communication, which can transmit information by open channel without encryption - removing key distribution problem, but in these protocols each bit of information is confidential and intruder shouldn’t get it, that's why requirements for protocols stability is much higher and require security amplification methods. Such method was previously developed by authors, but its implementation requires the use of reliable trit pseudorandom sequences. In this context, this study presents an experimental research of trit pseudorandom sequence generating method for cryptographic applications. For evaluating the effectiveness of this method was developed experimental methodology, which confirms the possibility of using trit sequences generated by the method for ensuring the stability of quantum cryptography qutrit protocols to non-coherent attacks and for other crypto-graphic applications in modern information and communication technologies.
The development of modern computer technologies endangers the confidentiality of information, which is usually ensured by traditional cryptographic means. This circumstance forces us to look for new methods of protection. In view of modern trends, quantum cryptography methods can become such alternatives, which allow solving a number of important cryptographic problems, for which the impossibility of solving using only classical (that is, non-quantum) communication has been proven. Quantum cryptography is a branch of quantum informatics that studies methods of protecting information by using quantum carriers. The possibility of such protection is ensured by the fundamental laws of quantum mechanics. One of the promising directions of quantum cryptography is Quantum Secure Direct Communication (QSDC) that offers secure communication without any shared key. A characteristic feature of this method is the absence of cryptographic transformations, accordingly, there is no key distribution problem. The purpose of this work is a general overview of quantum cryptography protocols, finding their weak points for further development and improvement, as well as identifying vulnerabilities to different attacks. The article analyzes new methods and protocols, as well as presents their advantages and disadvantages. Based on partial generalizations of theoretical provisions and practical achievements in the field of quantum cryptography, a generalized classification was developed. By comparing various factors of the protocols, and their resistance to certain cyberattacks, we have the opportunity to identify several problems in this field and expand the possibilities for choosing appropriate methods for building modern quantum information protection systems. In accordance with this, conclusions were presented regarding the use of protocols and increasing the level of their effectiveness.
The rapid development of modern computing technology threatens the confidentiality of information that is provided, usually, by traditional cryptographic means and forces researchers to look for alternative methods of security. Considering the development tendencies one of these alternatives may be quantum cryptography that unlike traditional (which is mostly based on the impossibility of solving a certain class of mathematical problems by certain period of time) uses specific unique properties of quantum particles, based on the inviolability of the quantum physics laws. It is known that some quantum cryptography protocols allowing to achieve information-theoretic stability – a key distribution protocols mostly. Another class of quantum cryptography protocols - secure direct communication protocols, most of which have asymptotic stability. Therefore, it was suggested a number of methods to increase the stability of such protocols. One of these methods will increase the asymptotic stability of quantum secure direct connection protocols with entangled pairs (correlated) of qutrit, but this method requires the generation of ternary (trit) pseudorandom sequences. In the work proposed generating pseudorandom trit sequences method based on the number of irreversible functions and transformation over the field GF (3). Also at the basis of a method developed appropriate algorithm that reflected as pseudo code. Further research will focus on the development of a quality evaluation of trit generated pseudorandom sequences method, as virtually all existing methods focused on binary sequence.
Traditional cryptographic methods have persistence, which are based on the alleged impossibility of solving a certain mathematical problem for a polynomial time. As an alternative quantum cryptography technologies don't depend on the computational capabilities of the intruder, because they use the unique properties of quantum particles, and are based on the principles of quantum physics laws inviolability. There are many methods and approaches used to solve the tasks of securing the privacy of message transmission without the use of encryption. One of the most advanced quantum cryptography technology is quantum direct secure communication, which allows information transmitting by an open channel without prior encryption. For this purpose, model of quantum deterministic protocol (for two modes of work) was created. Also the experimental studies of a deterministic protocol model in a channel with noise were carried out.
Thesis is devoted to applied scientific research task to develop and study new, more efficient methods for ensuring sustainability of quantum cryptography qutrit protocols to noncoherent attacks; constructing trit generator of pseudorandom sequences and evaluation of its quality (possibility of using them in cryptographic applications). The results obtained in the thesis can be used to improve efficiency (security level and speed) of security systems based on quantum direct secure communication and quantum key distribution, and can be used for security procedures in traditional (non-quantum) cryptographic information security systems. In this work developed classification of quantum cryptography methods, which, by extending the set of known basic features, partial theoretical generalizations and study practical achievements in quantum cryptography, can expand opportunities for choosing appropriate methods to construct modern quantum information security systems (based on quantum direct secure communication and other quantum technologies). Was further developed a method for ensuring stability of quantum cryptography qutrit protocols, which, with the use of quantum integrity checking function and trit symmetric function, allows to minimize the amount of switching between protocol modes (message transmission and eavesdropping control), and increase speed by a factor of 4.4, while maintaining the resistance to non-coherent attacks. Also, was further developed a method of generating pseudorandom sequences, which, through the implementation of new operation sequence (substitutions, linear diffusion, dynamic rotate shift, modular 3 and 3l addition) over internal states vector allows to create ternary unbalanced pseudorandom sequences. In addition, further developed a method for evaluating pseudorandom sequence quality, which, through complex interpretation of generated numbers, by adding differentiated probability , ternary coefficients for the error function erfc and incomplete gamma function igamc, enables to evaluate the statistical parameters and laws of ternary pseudorandom sequences.