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The city of Khorsabad (ancient Dūr-Šarrukīn), the newly built capital of Sargon II of Assyria, contained multiple instances of a sequence of five images or symbols (lion, bird, bull, tree, plow) which also appeared shortened to three (lion, tree, plow). What did they mean? There is currently no consensus. This paper proposes a new solution, suggesting that the images a) symbolize specific constellations and b) represent Babylonian/Assyrian words whose sounds "spell out" Sargon's name (this works for both the long and the short version). Combining these two traits, the effect of the symbols was to assert that Sargon's name was written in the heavens, for all eternity, and also to associate him with the gods Anu and Enlil, to whom the constellations in question were linked. It is further suggested that Sargon's name was elsewhere symbolized by a lion passant (pacing lion), through a bilingual pun. [ABSTRACT FROM AUTHOR]

The article examines the problems of primary processing and division into the optimal number of blocks of text information depending on the volume of text and steganographic audio container, to uniformly integrate it into wavelet coefficients over the entire frequency band at each level of the wavelet transform. Considering this, the main task of the research is to find the number of blocks of text information and the number of symbols in each block by calculating the maximum entropy of the wavelet coefficients of the audio container, which allows taking into account the energy spectral power of the text information and the audio signal in an absolute relationship between themselves. This will increase the efficiency of the audio steganosystem when compression algorithms are applied to an audio container with integrated text information for its intentional distortion. Since low-frequency wavelet coefficients with each subsequent level of wavelet decomposition will increase their absolute power due to the scalar product with wavelet filters, then the text information must be divided into such a number of blocks that its integration into low-frequency wavelet coefficients takes place from the minimum to the maximum values at each level of the wavelet transform, which will increase the average power of hidden text information. It should also be noted that statistical dependencies between symbols of text information do not allow us to approach its maximum entropy, therefore, it is necessary to remove statistical dependencies between symbols in text information, which is implemented using a pseudorandom number generator, which forms a sequence of evenly distributed numbers in a given interval. [ABSTRACT FROM AUTHOR]

In this paper, the properties of symbol transformations of cyclic Hadamard matrices are studied. An infinite class of (n − 1) -variable 2-resilient rotation symmetric Boolean functions are constructed, and the nonlinearity of the constructed functions is 2 n (n − 1). The crucial technique of this method is to determine a subset T ⊆ F 2 n − 1 satisfying a correspondent condition. This is a new construction of 2-resilient rotation symmetric Boolean functions via switching the supports of (n − 1) -variable rotation symmetric Boolean functions of degree one, i.e., f 0 n − 1 (x 1 , x 2 , ⋯ , x n − 1) = ⊕ i = 1 n − 1 x i , where n = 4 t. [ABSTRACT FROM AUTHOR]

Public-key cryptography provides security for digital systems and communication. Traditional cryptographic solutions are constantly improved, e.g., to suppress brute-force attacks. However, Shor's algorithm suited for quantum computers can break the bedrock of most currently used systems, i.e., the RSA problem and discrete logarithm problem. Post-quantum cryptography can withstand attacks carried out by quantum computers. Several families of post-quantum systems exist; one of them is isogeny-based cryptography. As a main contribution, in this paper, we provide a survey of chosen, fundamental isogeny-based schemes. The target audience of this review is researchers interested in practical aspects of this field of cryptography; therefore the survey contains exemplary implementations. Our goal was not to develop an efficient implementation, but to provide materials that make it easier to analyze isogeny-based cryptography. [ABSTRACT FROM AUTHOR]

SPECK and SPARX are two kinds of block ciphers with an ARX structure. In this paper, we use the SAT-based automatic search tool to search for linear approximations of these two ARX ciphers. As a result, we find a linear approximation for 17-round SPECK128, which covers one more round than previous work. Based on this linear approximation, we propose improved linear cryptanalysis for 19-round SPECK128/192 and 20-round SPECK128/256, which cover one more round than previous work. For ARX cipher SPARX, we find an optimal linear approximation for 13-round SPARX-64, which covers three more rounds than previous work. We also find an optimal linear approximation for 10-round SPARX-128, which covers two more rounds than previous work. Furthermore, we find a linear approximation for 14-round SPARX-128 by splicing two short linear approximations, which covers four more rounds than previous work. Based on these linear approximations, we propose linear cryptanalysis for 15-round SPARX-64/128, 15-round SPARX-128/128 and 16-round SPARX-128/256. [ABSTRACT FROM AUTHOR]

With the progress and development of life, cryptography became an indispensable science. As its usefulness is not limited to changing the form of information and making it in the form of symbols that are difficult to understand (even if it reaches unauthorized persons) but through it becomes known that the information is original and coming from its source and has not been modified during the sending or saving process. In this paper, we make an improvement and modification NTRU cryptosystem by using a new tripternion algebra and changing the mathematical structure for public and private keys, as well as for text encryption and decryption to obtain higher security. [ABSTRACT FROM AUTHOR]

This paper presents an efficient algorithm for computing 11th-power residue symbols in the cyclo-tomic field ℚ (ζ 11 ) , $ \mathbb{Q}\left({{\zeta }_{11}} \right), $ where 11 is a primitive 11th root of unity. It extends an earlier algorithm due to Caranay and Scheidler (Int. J. Number Theory, 2010) for the 7th-power residue symbol. The new algorithm finds applications in the implementation of certain cryptographic schemes. [ABSTRACT FROM AUTHOR]

The narration of ‘the King and the Maid’ as the first anecdote of Rumi's Masnavi after the section of Ney Name is one of the most serious stories of this poem and the most basic ideas of the poet are included in it. The high importance of this anecdote has caused many Masnavi scholars to interpret the meanings and explain its symbols. This issue leads to the emergence of multiple and often conflicting views. A group of commentators have considered the story of ‘the king and the maid’ as a symbolic story focusing on its symbols while another group, though emphasizing the importance of the anecdote, considered this kind of symbolism inappropriate to Rumi's taste and ingenuity. Having a correct judgment about such different views requires the use of framed methods of reading literary and artistic texts. Using Roland Barthes's method, thus, can be helpful. While distinguishing between a ‘readable text’ and ‘written text’, Barthes considered a written text to be a system of different codes that, in conjunction with each other, give rise to multiple meanings. Accordingly, he suggests analyzing the meaning in the text using the five hermeneutic, action, semantic, symbolic, and cultural codes. The purpose of the present study is to investigate the main discourses reinforced by different semantic levels of the text using a descriptive-analytical method. In this way, a scientific position was reached on resolving conflicts between commentators over the meaning of the symbols and the basic concepts of this story. The results of the study of text cryptography show that the three discourses of ‘sheikh, seeker’, ‘top side, bottom side’ and ‘trust, pride’ are the main discourses of the text and all cryptographies and semantic levels reinforce these discourses. In the context of the meaning of the symbols of the story, the focus on the main dualities of the text shows that this story symbolically represents the connection between the dimensions of human existence. According to Ibn Sina's views on how the soul belongs to the earthly body, the symbols of the anecdote can be interpreted as follows: the king is the symbol of the soul, the maid is the symbol of the body, and the goldsmith is the symbol of the world. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Education & Science is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A semi-quantum secret sharing scheme using entangled states was proposed in a recent paper [Mod. Phys. Lett. B32 (2018) 1850256. https://doi.org/10.1142/S0217984918502561 ]. We find a loophole of this scheme. Based on the intercept-resend attack, we propose a deterministic attack strategy and a probabilistic attack strategy. The malicious participant can escape the detection and obtains the secret. We also suggest two improvements to help increase the security of the original scheme. [ABSTRACT FROM AUTHOR]

Abstract In this work, we are interested in the steganography domain where the problem of security represents the basic key in the dissimulation of relevant information. The paper highlights two facets of research. The first facet represents a novel proposition of a naturally-inspired metaheuristic based on the smell sense of a honeybee insect. Herein, the collective foraging behavior is not explicitly intended but the search driven by smell sense is critical. The second facet highlights the proposition of two steganographic embedding schemes. The main idea behind the 2-Bit embedding scheme focus on the embedding rate of two secret bits by pixel. Compared to other steganographic algorithms, the intended bit that will support the elementary secret information can be anyone in the pixel byte provided that its content matches with the secret bit to embed. The proposed steganographic algorithm named HIBE takes advantage from transform domain since it presents more robustness against image processing attacks. And eventually, takes advantage from spatial domain since the lower distortion results achieved in comparison with other well-knew algorithm like HUGO, and WOW gives it more efficiency. Moreover, to evaluate its performance against steganalyzers methods based machine learning and classifiers some experiments were carried out on the BOSSbase dataset images. The reached results have shown that the used detectors, also well-knew, failed to classify the learned images as stego since their achieved detection accuracies approaches the random detection. [ABSTRACT FROM AUTHOR]

In this paper, we propose new method for automated cryptanalysis of substitution cryptosystem using Hill climbing algorithm. New heuristic function is proposed in order to drastically improve overall fitness of the standard Hill climbing algorithm. Several fitness functions have been tested and we try to detremine which of them perform better in specific situations using our suggested time-dependent measure goodness. We conclude which of those functions should be used in case we are dealing with short or long texts. [ABSTRACT FROM AUTHOR]

Designing an efficient and secure electronic voting (e-voting) protocol without the presence of trusted authorities, known as decentralized voting protocols, is one of the most interesting and challenging problems in cryptography. In these protocols the outcome of the protocol is computed by voters collaborating with each other. We provide a rigorous proof of security of a decentralized e-voting protocol proposed by Khader et al. in the Universal Composability (UC) Framework. This protocol is the state-of-the-art decentralized e-voting protocol in terms of efficiency and security, whose security has only been justified against a set of desired properties required in e-voting protocols. For security analysis of e-voting protocols, intuitive proof is not enough and we require a comprehensive approach that provides provable security. Our result settles this concern. [ABSTRACT FROM AUTHOR]

An effective steganographic scheme is proposed that combines pixel-value differencing, modulus function, and particle swarm optimization on the basis of previous research. In this paper, the difference between neighboring pixels in the carrier image is used. Pixel-value differencing and the modulus function are used to embed and extract secret information. Also, particle swarm optimization is used to select the ideal pixel gray values among numerous modulus function solutions to improve the quality of the stego-image. In the final experimental results, the proposed method had better embedded capacity and steganographic quality than schemes proposed by previous researchers. [ABSTRACT FROM AUTHOR]

Proxy re-signature is a powerful cryptographic primitive, in which a proxy acts as a translator converts Alice’s signature into Bob’s signature by using the re-signature key. Proxy re-signature is a very useful tool for the interoperable DRM architecture and the passed path proof in cloud computing. However, the number of cloud users is very huge, so it is unsuitable to construct PKI in cloud computing. Moreover, the cloud users are usually mobile devices, which are constrained with processing and power limitations, and pairing is a very costly operation to them. Thus, ID-based proxy re-signature without pairing is an attractive issue for the applications in cloud computing. In this paper, based on Chai et al’s ID-based signature from quadratic residues, we propose the first unidirectional and single-use ID-based proxy re-signature, which is existential unforgeable in the random oracle model based on the factoring assumption. [ABSTRACT FROM AUTHOR]

Proxy signature is a useful cryptographic primitive that has been widely used in many applications. It has attracted a lot of attention since it was introduced. There have been lots of works in constructing efficient and secure proxy signature schemes. In this paper, we identify a new attack that has been neglected by many existing proven secure proxy signature schemes. We demonstrate this attack by launching it against an identity-based proxy signature scheme which is proven secure. We then propose one method that can effectively prevent this attack. The weakness in some other proxy signature schemes can also be fixed by applying the same method. [ABSTRACT FROM AUTHOR]

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper introduces new techniques and correct complexity analyses for impossible differential cryptanalysis, a powerful block cipher attack. We show how the key schedule of a cipher impacts an impossible differential attack, and we provide a new formula for the time complexity analysis that takes this parameter into account. Further, we show, for the first time, that the technique of multiple differentials can be applied to impossible differential attacks. Then, we demonstrate how this technique can be combined in practice with multiple impossible differentials or with the so-called state-test technique. To support our proposal, we implemented the above techniques on small-scale ciphers and verified their efficiency and accuracy in practice. We apply our techniques to the cryptanalysis of ciphers including AES-128, CRYPTON-128, ARIA-128, CLEFIA-128, Camellia-256 and LBlock. All of our attacks significantly improve previous impossible differential attacks and generally achieve the best memory complexity among all previous attacks against these ciphers. [ABSTRACT FROM AUTHOR]

We present a new cryptographic primitive, called all-but-many encryption (ABME). An ABME scheme is a tag-based public-key encryption scheme with the following additional properties: A sender given the secret key can generate a fake ciphertext to open to any message with consistent randomness. In addition, anyone who does not own the secret key can neither distinguish a fake ciphertext from a real (honestly generated) one, nor produce a fake one (on a fresh tag) even after seeing many fake ciphertexts and their opening. A motivating application of ABME is universally composable (UC) commitment schemes. We prove that an ABME scheme implies a non-interactive UC commitment scheme that is secure against adaptive adversaries in the non-erasure model under a reusable common reference string. Previously, such a 'fully equipped' UC commitment scheme has been known only in Canetti and Fischlin (CRYPTO 2001, vol 2139, Lecture notes in computer science. Springer, Heidelberg, pp 19-40, 2001), Canetti et al. (STOC 2002, pp 494-503, 2002), with expansion factor $$O(\kappa )$$ , meaning that to commit $$\lambda $$ bits, communication strictly requires $$O(\lambda \kappa )$$ bits, where $$\kappa $$ denotes the security parameter. We provide a general framework for constructing ABME and several concrete instantiations from a variety of assumptions. In particular, we present an ABME scheme with expansion factor O(1) from DCR-related assumptions, which results in showing the first fully equipped UC commitment scheme with a constant expansion factor. In addition, the DCR-based ABME scheme can be transformed to an all-but-many lossy trapdoor function (ABM-LTF), proposed by Hofheinz (EUROCRYPT 2012, vol 7237, Lecture notes in computer science. Springer, Heidelberg, pp 209-227, 2012), with a better lossy rate than Hofheinz (2012). [ABSTRACT FROM AUTHOR]

A one-way function is d-local if each of its outputs depends on at most d input bits. In Applebaum et al. (SIAM J Comput 36(4):845-888, 2006), it was shown that, under relatively mild assumptions, there exist 4-local one-way functions (OWFs). This result is not far from optimal as it is not hard to show that there are no 2-local OWFs. The gap was partially closed in Applebaum et al. (2006) by showing that the existence of 3-local OWFs is implied by the intractability of decoding a random linear code (or equivalently the hardness of learning parity with noise). In this note we provide further evidence for the existence of 3-local OWFs. We construct a 3-local OWF based on the assumption that a random function of (arbitrarily large) constant locality is one-way. [A closely related assumption was previously made by Goldreich (Studies in Complexity and Cryptography. Miscellanea on the Interplay between Randomness and Computation, pp. 76-87, 2011).] Our proof consists of two steps: (1) we show that, under the above assumption, Random Local Functions remain hard to invert even when some information on the preimage x is leaked and (2) such 'robust' local one-way functions can be converted to 3-local one-way functions via a new construction of semi-private randomized encoding. We believe that these results may be of independent interest. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Qadisiyah Computer Science & Mathematics is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, we propose a partial reversible data hiding scheme using (7,4) Hamming code (PRDHHC) with secret position ( κ). In this scheme, we partition the original cover image into (7 × 7) pixel block and adjust redundant LSB bits of each row using odd parity. Then we calculate secret position κ = ( δ mod 7) + 1, where δ is a shared secret key. The bit at position κ and a suitable location for hidden message bit is modified through error creation caused by tamper in each row of the selected block. For the next row, the κ is updated by the data embedding position ( ω) of the previous row. We repeat this process to embed secret message bits within the selected block. For each new block, the κ is updated by κ = ( κ × δ × ω) mod 7 + 1, where i = 0, 1, 2, 3, . . . , number of blocks. At the receiver end, we complement the bit at position κ then retrieve the secret message bit by applying Hamming error correcting code. The extraction process will be stopped when we find continuous no error within stego image. The propose PRDHHC scheme extract the hidden message successfully and recover hamming adjusted cover image by complement bits at both the κ and ω positions but can not recover original cover image, that is to say, our scheme is partial reversible. Finally, we compared our scheme with other state-of-the-art methods and obtained reasonably better performance in terms of visual quality (measured by PSNR). Also we analyze our generated stego image using some steganalysis techniques which give promising results. [ABSTRACT FROM AUTHOR]

In this paper, a pentary steganography scheme is proposed employing the multi-layered STCs, which takes the embedding interactions into consideration. First, based on the definition of local correlation for the four-neighborhood, we link the modification direction of the central pixel with that of its four-neighborhood. Secondly, a modification degree strategy (MDS) is proposed to adjust the costs of the pixels dynamically. And the cost of pixels is assigned utilizing the MDS, which divides the process of distortion calculation into two steps of initializing and updating distortion cost. Finally, the scheme is obtained incorporating the MDS with the existing adaptive scheme S-UNIWARD of pentary version. Experimental results show that the proposed scheme is capable of providing large capacity, and has a better performance than adaptive steganography scheme S-UNIWARD of pentary version in resisting the SRM and maxSRMd2 detection when the payload is larger than 0.5 bpp. Also, the strategy could be combined with other adaptive steganography schemes of pentary version. Besides, the proposed scheme outperforms some ternary adaptive schemes with both feature sets SRM and maxSRMd2 when the payload is from 0.05bpp to 0.5bpp. [ABSTRACT FROM AUTHOR]

This paper presents a novel algorithm for high capacity image steganography, whose aim is to hide a scanned document as a message into a host image. In this approach, halftoning algorithm is applied to convert the gray-scale scanned document into a binary image, which is a sparse matrix. In the next step, an algorithm is proposed to read the the halftone image, and to convert each bit-stream of the sparse matrix into some meaningful decimal numbers, which are then to be embedded in 3-LSB bits of concealable pixels. Standard deviation is used in order to filter the concealable pixels of stego image and to preserve the quality of stego image. As a result, the smoother area that is sensitive to human visual system will not be chosen for embedding. The experiment results on 20 standard image, indicate that the PSNR measure and the embedding rate are 36.86 dB and 5.25 bpp in average, respectively, which are great progresses in comparison to the state-of-the-art. [ABSTRACT FROM AUTHOR]

XOR-based visual cryptography scheme (XVCS) was proposed to solve the poor visual quality problem without darkening the background in the reconstructed secret image. However, investigations on XVCS are not sufficient. In this paper, we focus on the traditional model of VCS for general access structures and exploit some extended capabilities for XVCS. Our main contributions are: (1) we put forward constructions of perfect contrast XVCS using the linear algebraic technique without any assumptions such as participants may carry multiple shares or prior information about the shares are to be submitted during the secret reconstruction phase; (2) for some restricted access structures, we achieve perfect contrast and perfect pixel expansion, namely both 1, which is impossible for any OR-based visual cryptography scheme (OVCS); (3) for general access structures, we achieve perfect contrast with smaller pixel expansion compared with many of the results in the literature; (4) Theoretical analysis on the proposed constructions are provided, as well as extensive experimental results and comparisons for demonstrating the effectiveness and advantages of our constructions. [ABSTRACT FROM AUTHOR]

Recently, Chen et al. proposed a framework for authenticated key exchange (AKE) protocols (referred to as CMYSG scheme) in Designs, Codes and Cryptography (available at ). It is claimed that the proposed AKE protocol is secure in a new leakage-resilient eCK model w.r.t. auxiliary inputs (AI-LR-eCK). The main tool used for the generic construction is the smooth projective hash function (SPHF). In this note, we revisit the CMYSG scheme and point out a subtle flaw in the original security proof. Precisely, we show that the AI-LR-eCK security of the proposed construction cannot be successfully reduced to a pseudo-random SPHF and thus the CMYSG scheme is not secure as claimed. To restore the security proof, we replace the underlying typical SPHF with a 2-smooth SPHF, and show that such a replacement combined with a $$\pi \hbox {PRF}$$ suffices to overcome the subtle flaw. [ABSTRACT FROM AUTHOR]

This paper takes a fresh look at security notions for steganography – the art of encoding secret messages into unsuspicious covertexts such that an adversary cannot distinguish the resulting stegotexts from original covertexts. However, stegosystems that fulfil the security notion used so far are quite inefficient. The current setting is not able to quantify the power of the adversary and thus leads to extremely high requirements. We will show that there exist stegosystems that are not secure with respect to the measure insecurity considered so far. However, it is totally unclear how they could be successfully attacked when used in practice. This indicates that a different notion of security is needed which we call detectability . We propose different variants of (un)-detectability and discuss their appropriateness by constructing concrete examples of stegosystems and covertext distributions. As main technical contribution we design a framework for steganography that exploits the difficulty to get detailed information about the covertext distribution. This way, for the first time a tight analytical relationship between the task of discovering the use of stegosystems and the task of differentiating between possible covertext distributions is obtained. [ABSTRACT FROM AUTHOR]

We consider security properties of cryptographic protocols that can be modelled using trace equivalence, a crucial notion when specifying privacy-type properties, like anonymity, vote-privacy, and unlinkability. Infinite sets of possible traces are symbolically represented using deducibility constraints. We describe an algorithm that decides trace equivalence for protocols that use standard primitives and that can be represented using such constraints. More precisely, we consider symbolic equivalence between sets of constraint systems, and we also consider disequations. Considering sets and disequations is actually crucial to decide trace equivalence for processes that may involve else branches and/or private channels (for a bounded number of sessions). Our algorithm for deciding symbolic equivalence between sets of constraint systems is implemented and performs well in practice. Unfortunately, it does not scale up well for deciding trace equivalence between processes. This is however the first implemented algorithm deciding trace equivalence on such a large class of processes. [ABSTRACT FROM AUTHOR]

The bizarre Voynich Codex, discovered in 1912 in Italy by the Polish book dealer Wilfrid Voynich (1864-1930), is written in a coded language with has eluded decipherment despite repeated attempts by world renowned cryptologists. Plant, animal, and mineral identifications as well as iconographic evidence indicate that the Voynich Codex is a 16th century work of New Spain. A typographical ligature based on the initials "JGT" in the first botanical image (folio 1v) suggests that artist was Juan Gerson, Tlacuilo, indigenous painter known for the apocalypse paintings in the monastery Asuncion de Nuestra Senora of Tecamachalco. The name "Gasp. Torres" also embedded in the first botanical image suggests that the author could be Gaspar de Torres, medical doctor, estate lawyer, master of students at the College of Santa Cruz in Tlatelolco from 1568-1572, and Governor of Cuba in 1580. Iconographic similarities between the paintings of Juan Gerson and the Voynich Codex, along with a biography of Gaspar de Torres provide additional support for this conjecture. [ABSTRACT FROM AUTHOR]

Security of data is always needed whenever communication is done and to achieve that purpose different techniques are used so that data should not be attacked by the third party. Different data concealing techniques like cryptography, watermarking etc. are used. But if we want the intruder not to even know about the presence of secret data we have to use the Steganography Technique. And this technique can be applied by using different files like text, audio, video etc. One of the steganography types as video steganography used to hide the secret data in an easy manner due to the complexity of its structure. We have different types of methods based upon Format, Cover, and Frequency in video steganography. This paper provides a review and analysis of the video steganography technique applied to AVI video file with LSB technique and the comparison of frames in the video file is analyzed with the help of different parameters to find how similar the cover video frame after embedding the secret data. The analysis is based on the PSNR, MSE, and the result is given. [ABSTRACT FROM AUTHOR]

Image steganography techniques can be classified into two major categories such as spatial domain techniques and frequency domain techniques. In spatial domain techniques the secret message is hidden inside the image by applying some manipulation over the different pixels of the image. This work attempts to detect the stego images created by WOW algorithm by steganalysis on images, based on the classification of selected Hybrid image feature sets. It uses Gini Index as the feature selection algorithm on the combined features of the Chen, SPAM and Ccpev. The main scope of this work is to compete the previously implemented SVM-spam and SVM-HT methods. It uses the standard classification performance metrics to evaluate the performance of the three of the steganalysis models SVM-spam, SVM-HT and SVM-HG (SVM with Hybrid features of Gini Index). [ABSTRACT FROM AUTHOR]

In this age of cloud computing, we tend to store data which we need frequently in web based cloud storage services so that it can be accessed whenever we need them. This not only provides an immense amount of flexibility to users but also makes our content accessible to us wherever we are and whenever we need them. We have many options in terms choosing web based cloud storage services for backing and archiving our data. There are many web based cloud storage services available out of which Amazon S3 and Google Drive are immensely popular among users. Backing up files so that they are not lost is an all-important step to ensure that nothing is ever lost. But, moving to the cloud is itself a big change and there are real concerns that make people pause before they sign up for any such service.This paper proposes and implements an algorithm which would encrypt the files uploaded on such web based cloud storage services and would decrypt the file once it has been downloaded using the keys that were generated during encryption. This would prevent unwanted intrusion into personal data and lack of standardization, i.e. one service provider may have end-to-end encryption while others do not. [ABSTRACT FROM AUTHOR]

In this paper, we propose a threshold increasing algorithm for a (t,n) latticebased Threshold Multi-Stage Secret Sharing (TMSSS) scheme. To realize the changeability feature, we use the zero addition protocol to construct a new (t',n) TMSSS scheme. Therefore, the new scheme enjoys the significant feature of threshold changeability along with the inherited features of being multi-stage, multi-use, and verifiable derived from our previously proposed lattice-based TMSSS scheme. Furthermore, we use the improved TMSSS scheme to propose a threshold decryption algorithm for the Learning With Error (LWE) based public key encryption scheme based on the study of Lindner and Peikert. For threshold decryption, each authorized subset of participants decrypts the ciphertext partially and sends the result to the combiner. The combiner can decrypt the ciphertext using the partial decryptions. The security of both schemes is based on hardness of lattice problems, i.e. LWE and Inhomogeneous Small Integer Solution (ISIS) problems, which are believed to resist against the quantum algorithms. The proposed schemes are efficient, especially on the participants' side, making them suitable for the applications in which the participants have limited processing capacities. [ABSTRACT FROM AUTHOR]

This article presents a signature-free distributed algorithm which builds an atomic read/write shared memory on top of a fully connected peer-to-peer n-process asynchronous message-passing system in which up to t< n/3 processes may commit Byzantine failures. From a conceptual point of view, this algorithm is designed to be as close as possible to the algorithm proposed by Attiya, Bar-Noy and Dolev. J. ACM 42(1), 121-132 (1995), which builds an atomic register in an n-process asynchronous message-passing system where up to t< n/2 processes may crash. The proposed algorithm is particularly simple. It does not use cryptography to cope with Byzantine processes, and is optimal from a t-resilience point of view ( t< n/3). A read operation requires O( n) messages, and a write operation requires O( n ) messages. [ABSTRACT FROM AUTHOR]

Public-Key Cryptography (PKC) based on multivariate quadratic equations is one of the most promising alternatives for classical PKC after the eventual coming of quantum computers. Recently, Shen and Tang proposed a new MQ-signature scheme, RGB, based on three types of variables, Red( r ), Green( g ) and Blue( b ). They claimed that signing for RGB is faster than that of UOV and Rainbow. At ACISP 2016, Tang et al. implemented RGB on S5PV210 and MT6582 microprocessors at 64, 80, 96, 118 and 128-bit security levels for practical use. Their results are much more efficient than other MQ-signature schemes, so RGB is very appealing for resource-limited devices. We show that RGB with their suggested parameters at 64, 80, 96, 118 and 128 security levels are entirely broken by key recovery attacks using good keys. From a practical point of view, we are able to break their parameters at 64, 80, 96, 118 and 128 security levels in less than 0.48 seconds, 1.7 seconds, 90.68 seconds, 11 minutes and 6.82 hours, respectively. Consequently, we show that signing and the key sizes for RGB with secure parameter sets are much slower and larger than those of UOV and Rainbow. [ABSTRACT FROM AUTHOR]

Steganography, such as secret sharing, is an important technique to use for protecting transmitted confidential data from the attention of any adversaries. Gray code is a commonly encountered binary labeling that was proposed by Frank Gray of Bell Laboratories in 1940 to prevent errors when using pulse-code modulation to transmit signals. The main features of Gray code are its recursive construction method and the fact that any two adjacent codes change only one bit. According to our observations, the image pixel correction based on these features is suitable for application secret sharing without making significant changes to the pixel value. We designed a reversible secret sharing method using meaningful image shadows based on Gray code. Our design applies absolute moment block truncation coding (AMBTC) compression to reduce the transmission bit rate. The experimental results show that our scheme can achieve the adequate visual quality of shadow images with lower communication overhead, thus proving it practical for numerous applications. [ABSTRACT FROM AUTHOR]

In this work, a cubic spline curve is considered for Asymmetric mode encrypting data. A Cubicspline curve is used to generate a set of points under initial known boundary conditions. This set of points is considered as generator points. Given the field, known the generator points, considering for some time and space steps and for a considered private key, Public key will be generated based on Discrete Logarithm problem. Thus for a set of public and private keys, data can be transmitted securely with features like Authenticity of users, Security & Confidentiality of data transmitted. Going by the construction of the algorithm, Encryption is being done on blocks of data for which it consumes less computing resources. Going by complexity of the algorithm, the key length needed is about 120 bit lengths to provide sufficient strengths against cryptoanalysis. [ABSTRACT FROM PUBLISHER]

Here in this model, a new mechanism is used for Public Key Cryptography. A generator matrix is used to generate a field with a large prime number. The generator matrix, prime number and quaternary vector are used as global variables. The Generator Matrix is powered by a private key to generate Public Key. Since the model is based on Discrete Logarithm Problem, which is Hard problem, the proposed algorithm supports the features like Authenticity of users, Security & Confidentiality of data transmitted. Going by the construction of the algorithm, Encryption is being done on blocks of data for which it consumes less computing resources. Going by complexity of the algorithm, the key length needed is about 72 bit lengths to provide sufficient strengths against crypto analysis. [ABSTRACT FROM PUBLISHER]

Image steganography is the art of hiding highly sensitive information onto the cover image. An ideal approach to image steganography must satisfy two factors: high quality of stego image and high embedding capacity. Conventionally, transform based techniques are widely preferred for these applications. The commonly used transforms for steganography applications are Discrete Cosine Transform (DCT), Discrete Wavelet Transform (DWT) etc. In this work, frequency domain transforms such as Fresnelet Transform (FT) and Contourlet Transform (CT) are used for the data hiding process. The secret data is normally hidden in the coefficients of these transforms. However, data hiding in transform coefficients yield less accurate results since the coefficients used for data hiding are selected randomly. Hence, in this work, optimization techniques such as Genetic Algorithm (GA) and Particle Swarm Optimization (PSO) are used for improving the performance of the steganography system. GA and PSO are used to find the best coefficients in order to hide the Quick Response (QR) coded secret data. This approach yields an average PSNR of 52.56 dB and an embedding capacity of 902,136 bits. These experimental results validate the practical feasibility of the proposed methodology for security applications. [ABSTRACT FROM AUTHOR]

Recently, Wang et al. (J Secur Commun Netw 5(12):1363-1374, 2012) proposed a self-healing group key distribution (SGKD) scheme for resource-constrained wireless networks. They claimed that their proposed SGKD scheme satisfies forward security, backward security and can resist collusion attack. Unfortunately, we found some security flaws in their scheme. In this paper, we present a method to attack this scheme. The attack illustrates that this scheme does not satisfy forward security, which also directly breaks the collusion resistance capability. We also propose an improved scheme with constant storage overhead and satisfactory security. [ABSTRACT FROM AUTHOR]

In this paper we introduce a multi secret sharing (MSS) scheme based on lattice conception. Lattice constitutes the core of many cryptographic constructions. The advantage of using lattice, which our scheme will inherit, is twofold: first is that the hardness of lattice problems is well understood. We will show that breaking our scheme leads to a solution for the robust Short Integer Solution problem. Hence, the presented scheme's security is guaranteed by leveraging lattice based conceptions. Second advantage is that working with lattice is simple and, consequently, execution is fast. A main problem with previous schemes is that they mostly are based on numerical assumptions which are slow and need much throughput. Inheriting simplicity and fastness make our scheme an excellent choice to implement in facilities with limit computational power and resources. In secret sharing schemes, typically in any protocol, dishonest participants and dealer can cheat during execution. To mitigate these concerns we augment our scheme with verifiability properties, say verifiable and public verifiable secret sharing. Verifiability prevents the dealer to share wrong shares and public verifiability forces participants to submit their sub-shares correctly. In MSS schemes, releasing some public values which are used in recovering step is inevitable. At the end, a comprehensive comparison by a table in the conclusion section shows that the presented scheme has minimum number of public values among MSS schemes. [ABSTRACT FROM AUTHOR]

A mutual information rate is proposed to quantitatively evaluate inter-process synchronized communication. For finite-state processes with implicit communication that can be described by a counting language, it is shown that the mutual information rate is effectively computable. When the synchronization always happens between the same two symbols at the same time (or with a fixed delay), the mutual information rate is computable. In contrast, when the delay is not fixed, the rate is not computable. Finally, it is shown that some cases exist where the mutual information rate is not computable. [ABSTRACT FROM AUTHOR]

The detection of moving objects in a video sequence is the first step in an automatic video surveillance system. This work proposes an enhancement of a codebook-based algorithm for moving objects extraction. The proposed algorithm used a perceptual-based approach to optimize foreground information extraction complexity by using a modified codebook algorithm. The purpose of the adaptive strategy is to reduce the computational complexity of the foreground detection algorithm while maintaining its global accuracy. In this algorithm, we use a superpixels segmentation approach to model the spatial dependencies between pixels. The processing of the superpixels is controlled to focus it on the superpixels that are near to the possible location of foreground objects. The performance of the proposed algorithm is evaluated and compared to other algorithms of the state of the art using a public dataset that proposes sequences with a dynamic background. Experimental results prove that the proposed algorithm obtained the best the frame processing rate during the foreground detection. [ABSTRACT FROM AUTHOR]