On the Condition of Covering Completeness in Associative Steganography

Previously, the completeness of the coverage was considered by the authors as an interpretation of a kind of logical interpretation of the criterion of perfect secrecy by K. Shannon – one of the necessary conditions that the concept of associative steganography should satisfy. The article shows that in reality, the completeness of coverage is a completely independent condition for ensuring the required level of data protection when analyzing scenes. It should not be associated with the criterion of K. Shannon.

Splitting authentication codes with perfect secrecy: New results, constructions and connections with algebraic manipulation detection codes

<p style='text-indent:20px;'>A splitting BIBD is a type of combinatorial design that can be used to construct splitting authentication codes with good properties. In this paper we show that a design-theoretic approach is useful in the analysis of more general splitting authentication codes. Motivated by the study of algebraic manipulation detection (AMD) codes, we define the concept of a <i>group generated</i> splitting authentication code. We show that all group-generated authentication codes have perfect secrecy, which allows us to demonstrate that algebraic manipulation detection codes can be considered to be a special case of an authentication code with perfect secrecy.</p><p style='text-indent:20px;'>We also investigate splitting BIBDs that can be "equitably ordered". These splitting BIBDs yield authentication codes with splitting that also have perfect secrecy. We show that, while group generated BIBDs are inherently equitably ordered, the concept is applicable to more general splitting BIBDs. For various pairs <inline-formula><tex-math id="M1">\begin{document}$ (k, c) $\end{document}</tex-math></inline-formula>, we determine necessary and sufficient (or almost sufficient) conditions for the existence of <inline-formula><tex-math id="M2">\begin{document}$ (v, k \times c, 1) $\end{document}</tex-math></inline-formula>-splitting BIBDs that can be equitably ordered. The pairs for which we can solve this problem are <inline-formula><tex-math id="M3">\begin{document}$ (k, c) = (3, 2), (4, 2), (3, 3) $\end{document}</tex-math></inline-formula> and <inline-formula><tex-math id="M4">\begin{document}$ (3, 4) $\end{document}</tex-math></inline-formula>, as well as all cases with <inline-formula><tex-math id="M5">\begin{document}$ k = 2 $\end{document}</tex-math></inline-formula>.</p>

Cryptobiometrics for the Generation of Cancellable Symmetric and Asymmetric Ciphers with Perfect Secrecy

Security objectives are the triad of confidentiality, integrity, and authentication, which may be extended with availability, utility, and control. In order to achieve these goals, cryptobiometrics is essential. It is desirable that a number of characteristics are further met, such as cancellation, irrevocability, unlinkability, irreversibility, variability, reliability, and biometric bit-length. To this end, we designed a cryptobiometrics system featuring the above-mentioned characteristics, in order to generate cryptographic keys and the rest of the elements of cryptographic schemes—both symmetric and asymmetric—from a biometric pattern or template, no matter the origin (i.e., face, fingerprint, voice, gait, behaviour, and so on). This system uses perfect substitution and transposition encryption, showing that there exist two systems with these features, not just one (i.e., the Vernam substitution cipher). We offer a practical application using voice biometrics by means of the Welch periodogram, in which we achieved the remarkable result of an equal error rate of (0.0631, 0.9361). Furthermore, by means of a constructed template, we were able to generate the prime value which specifies the elliptic curve describing all other data of the cryptographic scheme, including the private and public key, as well as the symmetric AES key shared between the templates of two users.