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.
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 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.
Quantum cryptography doesn’t depend on computational capabilities of intruders; it uses inviolability of quantum physics postulates (postulate of measurement, no-cloning theorem, uncertainty principle). Some quantum key distribution protocols have absolute (theoretical and informational) stability, but quantum secure direct communication (deterministic) protocols have only asymptotic stability. For a whole class of methods to ensure Q-trit deterministic quantum cryptography protocols stability, reliable trit generation method is required. In this paper, authors have developed a high-speed and secure pseudorandom number (PRN) generation method. This method includes the following steps: initialization of the internal state vector and direct PRN generation. Based on this method TriGen v.2.0 pseudo-random number generator (PRNG) was developed and studied in practice. Therefore, analysing the results of study it can be concluded following: 1) Proposed Q-trit PRNG is better then standard C ++ PRNG and can be used on practice for critical applications; 2) NIST STS technique cannot be used to evaluate the quality (statistical stability) of the Q-trit PRNG and formed trit sequences; 3) TritSTS 2020 technique is suitable for evaluating Q-trit PRNG and trit sequences quality. A future research study can be related to developing a fully-functional version of TritSTS technique and software tool.
Due to the fundamentally different approach underlying quantum cryptography (QC), it has not only become competitive, but also has significant advantages over traditional cryptography methods.Such significant advantage as theoretical and informational stability is achieved through the use of unique quantum particles and the inviolability of quantum physics postulates, in addition it does not depend on the intruder computational capabilities.However, even with such impressive reliability results, QC methods have some disadvantages.For instance, such promising trend as quantum secure direct communicationeliminates the problem of key distribution, since it allows to transmit information by open channel without encrypting it.However, in these protocols, each bit is confidential and should not be compromised, therefore, the requirements for protocol stability are increasing and additional security methods are needed.For a whole class of methods to ensure qutrit QC protocols stability, reliable trit generation method is required.In this paper authors have developed and studied trit generation method and software tool TriGen v.2.0 PRNG.Developed PRNG is important for various practical cryptographic applications (for example, trit QC systems, IoT and Blockchain technologies).Future research can be related with developing fully functional version of testing technique and software tool.
Developments in quantum cryptography are carried by almost all major western telecommunication companies and research centers. Rapid development led to a significant expansion of the protocols range. From viewpoint of information capacity the most effective protocols for quantum cryptography system is trit systems. However, there is a problem of developing trit pseudorandom sequences generators and assessing their quality. This is because random and pseudo-random sequence generated by different generators for cryptographic applications must be tested by probabilistic and statistical methods. However, the vast majority of known techniques focused on testing generators pseudorandom binary sequences, so confirm pseudorandom generated trit sequences using them is almost impossible. Also there are not existed software and methods of such sequences assessment and arises the task of method developing for evaluation the quality of ternary pseudorandom sequences to evaluate the feasibility of using them for cryptographic applications. That method was developed in this paper and it is based on the approach used in NIST STS.Keywords: quantum cryptography, trit, qutrit, pseudorandom sequence, pseudorandom sequences generator, quality assessment.
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.
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.