Encryption Research Articles

Efficient Public Encryption Scheme with Keyword Search for Cloud Storage

Efficient Public Encryption Scheme with Keyword Search for Cloud Storage

Adaptively Simulation-Secure Attribute-Hiding Predicate Encryption

This paper demonstrates how to achieve simulation-based strong attribute hiding against adaptive adversaries for predicate encryption (PE) schemes supporting expressive predicate families under standard computational assumptions in bilinear groups. Our main result is a simulation-based adaptively strongly partially-hiding PE (PHPE) scheme for predicates computing arithmetic branching programs (ABP) on public attributes, followed by an inner-product predicate on private attributes. This simultaneously generalizes attribute-based encryption (ABE) for boolean formulas and ABP's as well as strongly attribute-hiding PE schemes for inner products. The proposed scheme is proven secure for any a priori bounded number of ciphertexts and an unbounded (polynomial) number of decryption keys, which is the best possible in the simulation-based adaptive security framework. This directly implies that our construction also achieves indistinguishability-based strongly partially-hiding security against adversaries requesting an unbounded (polynomial) number of ciphertexts and decryption keys. The security of the proposed scheme is derived under (asymmetric version of) the well-studied decisional linear (DLIN) assumption. Our work resolves an open problem posed by Wee in TCC 2017, where his result was limited to the semi-adaptive setting. Moreover, our result advances the current state of the art in both the fields of simulation-based and indistinguishability-based strongly attribute-hiding PE schemes. Our main technical contribution lies in extending the strong attribute hiding methodology of Okamoto and Takashima [EUROCRYPT 2012, ASIACRYPT 2012] to the framework of simulation-based security and beyond inner products.

Combination of Cryptography Algorithm Knapsack and Run Length Enconding (RLE) Compression in Treatment of Text File

The Knapsack algorithm cryptographic method is asymmetric cryptography in which the encryption key is different from the decryption key. In addition to text file security issues, the issue of the size of a text file is also a consideration. Large text files can be compressed by doing the compression process. Run Length Encoding (RLE) algorithm is an algorithm that reduces the size of a text file, if the text has a lot of repetition of characters. The combination of Knapsack and RLE algorithms can guarantee Text files cannot be seen by unauthorized users and can guarantee text files can be stored in low capacity media files. In this study, the authors made a combination of knapsack and RLE algorithm in text files. In the Knapsack algorithm there will be an increase in the size of the text file, this can be seen in the example of a case where the size of the plaintext (the original message) is 9 bytes, then after the encryption process the text file size becomes 7 bytes. Because of that the use of a combination of encryption and data compression is better because the file becomes smaller than the combination of data compression and encryption. Plaintext that has a lot of repetition of characters will be well compressed.

Secure Storage Method of Ship Communication Data Based on Double Key and Hadoop

Yang, H.; Zhang, C., and Zhao, B., 2020. Secure storage method of ship communication data based on double key and Hadoop. In: Yang, Y.; Mi, C.; Zhao, L., and Lam, S. (eds.), Global Topics and New Trends in Coastal Research: Port, Coastal and Ocean Engineering. Journal of Coastal Research, Special Issue No. 103, pp. 952–955. Coconut Creek (Florida), ISSN 0749-0208.In order to improve the security storage and transmission ability of ship communication data, it is necessary to dynamically encrypt the ship communication data, and a dynamic encryption method of ship communication data based on double key and Hadoop is proposed. The secure key transmission model of ship communication data is constructed, the multidimensional mapping structure of ship communication data is reorganized by the method of spatial quantization coding, the encryption protocol of double key automatic control of ship communication data is established, the double key Hadoop cloud platform coding configuration method is adopted, the double key random quantization coding and feature fusion processing of ship communication data are carried out, the encryption key and decryption key are constructed, and the dynamic encryption design of ship communication data is carried out according to the results of double key encryption and Hadoop cloud platform storage. The simulation results show that the security of dynamic encryption of ship communication data using this method is better, and the fidelity of ship communication data transmission is higher, which improves the security storage ability of ship communication data and the ability of resisting attack.

Identity Based Broadcast Encryption Scheme with Shorter Decryption Keys for Open Networks

In Broadcast Encryption schemes, a sender can broadcast the encrypted message securely in a threatening network to a set of legitimate system users only. In IBE scheme any sender can encrypt the desired message using his/her identity without attaining the public key certificate. Here, we have presented an efficient ID-based broadcast encryption scheme (IBBE) for open networks. In this scheme, desired messages can be broadcasted to any subset of the users by any sender but only authorized receivers are capable in retrieving the encrypted messages. This scheme has shorter decryption keys in comparison with other primitive of IBBE scheme for open networks. Moreover, the proposed scheme intends to achieve the lower cost for computation as well as transmission in comparison to earlier existing IBBE schemes.

Incorporation of Multiple Sources into IT - and Data Protection Concepts: Lessons Learned from the FARKOR Project.

The IT- and data protection concept of the FAmiliäres Risiko für das KOloRektale Karzinom (FARKOR) project will be presented. FARKOR is a risk adapted screening-project in Bavaria, Germany focusing on young adults with familial colorectal cancer (CRC). For each participant, data from different sources have to be integrated: Treatment records centrally administered by the resident doctors association (KVB), data from health insurance companies (HIC), and patient reported lifestyle data. Patient privacy rights must be observed. Record Linkage is performed by a central independent trust center. Data are decrypted, integrated and analyzed in a secure part of the scientific evaluation center with no connection to the internet (SECSP). The presented concept guarantees participants privacy through different identifiers, separation of responsibilities, data pseudonymization, public-private key encryption of medical data and encrypted data transfer.

Secure Collapsing Method Based on Fully Homomorphic Encryption.

In this paper, we propose a new approach for performing privacy-preserving genome-wide association study (GWAS) in cloud environments. This method allows a Genomic Research Unit (GRU) who possesses genetic variants of diseased individuals (cases) to compare his/her data against genetic variants of healthy individuals (controls) from a Genomic Research Center (GRC). The originality of this work stands on a secure version of the collapsing method based on the logistic regression model considering that all data of GRU are stored into the cloud. To do so, we take advantage of fully homomorphic encryption and of secure multiparty computation. Experiment results carried out on real genetic data using the BGV cryptosystem indicate that the proposed scheme provides the same results as the ones achieved on clear data.

MedCo2: Privacy-Preserving Cohort Exploration and Analysis.

Medical studies are usually time consuming, cumbersome and extremely costly to perform, and for exploratory research, their results are also difficult to predict a priori. This is particularly the case for rare diseases, for which finding enough patients is difficult and usually requires an international-scale research. In this case, the process can be even more difficult due to the heterogeneity of data-protection regulations, making the data sharing process particularly hard. In this short paper, we propose MedCo2 (pronounced MedCo square), a distributed system that streamlines the process of a medical study by bridging and enabling both data discovery and data analysis among multiple databases, while protecting data confidentiality and patients' privacy. MedCo2 relies on interactive protocols, homomorphic encryption and differential privacy. It enables the privacy-preserving computations of multiple statistics such as cosine similarity and variance, and the training of machine learning models, on patients that are obliviously selected according to specific criteria among multiple databases.

Efficient ciphertext-policy attribute-based encryption with blackbox traceability

Traitor tracing scheme is a paradigm to classify the users who illegal use of their decryption keys in cryptosystems. In the ciphertext-policy attribute-based cryptosystem, the decryption key usually contains the users’ attributes, while the real identities are hidden. The decryption key with hidden identities enables malicious users to intentionally leak decryption keys or embed the decryption keys in the decryption device to gain illegal profits with a little risk of being discovered. To mitigate this problem, the concept of blackbox traceability in the ciphertext-policy attribute-based scheme was proposed to identify the malicious user via observing the I/O streams of the decryption device. However, current solutions with blackbox traceability are impractical since either the composite-order group or the linear complexity of system users is required. In this article, we proposed a secure ciphertext-policy attribute-based set encryption scheme with the short decryption key. The proposed scheme bases on the prime-order group to improve computational performances and aggregates multiple attributes into a constant-size attribute set to reduce the costs of communication overheads. By applying our proposed scheme with fingerprint codes, we then give an instantiation of the ciphertext-policy attribute-based scheme with blackbox traceability. Our scheme is provably secure under various q-type assumptions.

Cryptocurrencies: The ultimate fate

Cryptocurrencies are a sort of digital money created and managed through the use of advanced encryption techniques known as cryptography. This paper has made a simple explanation of cryptocurrencies (particularly Bitcoin) as well as an attempt to make some future assumptions regarding such virtual currencies with the aid of previous literature and published online sources. The various aspects of these virtual currencies are yet to be discovered in detail, but the author hopes that this simple, basic and narrative paper will be helpful to those seeking basic references regarding this newest issue.

An asymmetric image encryption mechanism using QR decomposition in hybrid multi-resolution wavelet domain

In this paper, an asymmetric image encryption mechanism using QR decomposition technique in hybrid multi-resolution wavelet (HMW) domain is presented. QR decomposition technique utilized here makes the system asymmetric, as the obtained permutation matrix serves as ciphertext and the product of orthogonal and triangular matrices act as decryption keys. It also enables compression as the ciphertext obtained through QR decomposition is a sparse matrix which can be stored using CSR method. The HMW is obtained by utilizing existing orthogonal transforms: Walsh transform and fractional Fourier transform (frFT). Here the fractional orders of fractional Fourier transform (frFT) matrices are employed here to generate HMW, which function as supplementary keys. Therefore, they enhance the key space and strengthen the proposed system. The proposed encryption system exhibits non-linearity and enlarged key-space to dodge any brute-force attack. Computer-based simulations have been carried out on the grayscale images to verify and validate the proposed encryption mechanism. And the results obtained clearly demonstrate the robustness of the proposed mechanism against occlusion and noise attacks.

Implementasi Algoritma Massey-Omura dan Algoritma Elias Delcta Code Pada Pengamanan dan Kompresi File Dokumen

The rapid development of information technology requires users to be more careful in maintaining data confidentiality and security so that data is not known or manipulated by other parties. Data security is very important for users, data security can be maintained by everyone. Cryptography is one of the security tools used to encode a document file. One of them is by using the Massey-Omura algorithm, which is an asymmetric cryptographic algorithm, so that it has different keys for encryption and decryption. In the process of sending data, it also requires the duration of sending files to not give an opportunity to data thieves by compressing the data or reducing the size of the file to be smaller without losing the contents of the document file, so the data exchange process can be shorter Data compression is a process where text, audio, and video files are transformed into compressed files with smaller data sizes but do not lose the actual information. This study discusses the type of lossless compression, so that files obtained from decompression will be identical to the original data. Elias Delta Code is a type of lossless compression. The performance parameters of this algorithm will be measured by Ratio of Compression (RC, Space Saving (SS) and compression time. Data used in the testing process is data that consists of several types of characters. In this discussion will include explanation, how to work, advantages and The author will also try to provide a review of ways to improve the security level of document files.

Encryptsy – An AES Encrypted System for voice/data over Internet using DigiKey and VPN

Encryptsy – An AES Encrypted System for voice/data over Internet using DigiKey and VPN

On developing dynamic and efficient cryptosystem for safeguarding healthcare data in public clouds

With the greater development in internet, in medical field, all the confidential information about the patients and their test results are maintained in any of the remote servers around the world. Because of the confidentiality to be maintained in case of handling the patient related data, it is very crucial that the data is handled only by the authorized personnel. In the conventional method of data storage, the data are normally encrypted in the patient’s side and then they are kept securely in remote cloud server. So, the patient is empowered to decide the visibility of his data, hence becomes the data owner. But, the main disadvantage of this approach is its restricted data availability for the doctors who need to access the medical data. In this paper we propose two dynamic and efficient cryptosystems for secure storage and access of medical data. First algorithm exploits the High Secure Encryption Standard scheme, which has the advantage of making an encrypted data stored in the remote cloud is available for searching. Moreover, this approach ensures security and privacy both in patient’s side and the doctor’s side. Also, we propose another approach for developing a key management system, which will effectively handle the allocation of encryption and decryption keys for all the people who are handling the sensitive medical data of the patients. The experimental results show that our proposed model of cryptosystem ensures that the data has been stored and retrieved with higher security with relatively optimized searching time. Moreover, this approach is very efficient in terms of space complexity, search indexing and secret access of data comparing with many of the existing algorithms.

Updatable Attribute-Based Encryption Scheme Supporting Dynamic Change of User Rights

Updatable Attribute-Based Encryption Scheme Supporting Dynamic Change of User Rights

Exploiting Random Chemistry for Digital Security

Randomness is such an important resource of our digital information era that new random number generators are invented continuously. Typically, these are electronic devices. Recently, researchers of the Universities of Glasgow and Edinburgh devised a novel method using stochastic chemical reactions.

New symmetric key cipher capable of digraph to single letter conversion utilizing binary system

In this paper, a new Playfair cipher built on bits level symmetric key cryptographic was proposed for the purpose of converting pairs of letters (digraphs) into single letters. The proposed algorithm is capable to overcome many of the shortcoming and vulnerabilities that exist in the current classical version of Playfair algorithm. The Playfair cipher is exceedingly complex than a classical substitution cipher, but still simple to hack using automated tactics. It is famous as a digraph cipher because two letters are exchanged by other two letters. This destroys any solo letter occurrence statistics, but the digraph statistics still unaffected (frequencies of two letters). Unluckily letter pairs have a flatter distribution than the one letter frequencies, so this intricacy matters for solving the code using pen and paper procedures. The suggested encryption process is conducted as follows; letters are first arranged in a spiral manner in Polybius square, afterwards, each pair will be replaced utilizing before-after technique if we are arranging pairs horizontally and down-up technique (vertically). The former process produces pairs of Plaintext that will be converted to binary bit stream then will be divided over blocks with stable sizes. Bits of these blocks are taken from pairs then fit them into square matrix of suitable order to put the concept of row-wise and revers row-wise matrix. Bits of this matrix are split into 2x2 square matrixes. The sub-matrixes are formed 8 bits. Here the XNOR operation is taken into consideration for bitwise operation to generate the keys for decryption and produce the cipher-text.

Machine learning algorithm for a homomorphic encrypted data set

Machine learning algorithm for a homomorphic encrypted data set

Quantum Key Distribution Based-on Refraction and Polarization Entanglement

Cryptography is the specialty of encoding and decoding messages and exists as extended as the individuals have doubted from one another and need secure correspondence. The traditional techniques for encryption naturally depend on any among public key or secret key approaches. In general, the public key encryption depends on two keys, for example, public key and private key. Since encryption and decryption keys are different, it isn't important to safely distribute a key. In this approach, the difficult of the numerical issues is assumed, not demonstrated. All the security will be easily compromised if proficient factoring algorithms are found. In secret key encryption two clients at first create secret key, which is a long string of arbitrarily selected bits and safely shares between them. At that point the clients can utilize the secret key along with the algorithms to encryption and decryption information. The procedures are complicated and also planned such a way that every bit of output is based on every bit of input. There are two fundamental issues with secret key encryption; first one is that by breaking down the openly known encoding algorithms, it gets simpler to decrypt the message. The subsequent one is that it experiences key-conveyance issue. As a result of the ongoing improvements in quantum processing and quantum data hypothesis, the quantum computers presents genuine difficulties to generally utilized current cryptographic strategy. The improvement of quantum cryptography beat the deficiencies of old style cryptography and achieves these huge accomplishments by using the properties of infinitesimal articles, for example, photon with its polarization and entangled state. In this paper, Polarization by refraction based quantum key distribution (PR-QKD) is proposed for quantum key generation and distribution. The proposed work considers three basis of polarization such as rectilinear (horizontal and vertical), circular (left-circular and right-circular), ellipse (left-ellipse and right-ellipse) and refraction factor. This quantum key can be used for secure communication between two users who are spatially separated and also offer intrusion detection ability to detect attackers. The theoretical approach and conceptual results are discussed in this paper.

Quantum Search on Encrypted Data Based on Quantum Homomorphic Encryption

We propose a homomorphic search protocol based on quantum homomorphic encryption, in which a client Alice with limited quantum ability can give her encrypted data to a powerful but untrusted quantum server and let the server search for her without decryption. By outsourcing the interactive key-update process to a trusted key center, Alice only needs to prepare and encrypt her original data and to decrypt the ciphered search result in linear time. Besides, we also present a compact and perfectly secure quantum homomorphic evaluation protocol for Clifford circuits, where the decryption key can be calculated by Alice with polynomial overhead with respect to the key length.