A PRISMA-compliant systematic review and analysis on color image encryption using DNA properties

Data breach in cloud storage is a major issue that is still prevailing in cloud environment. Patient data is one of the sensitive information that is of interest to adversaries. In recent days, many techniques for securing the data has been evolving and techniques to break those schemes are also evolving. In this paper, an effort has been made to secure patient data – text and scan images, using modified Elgamal for text and permutation preceded blowfish scheme for scan images. Authorized users are granted access control using Role based Access Control (RBAC) mechanism. The modified Elgamal for text and permutation for image adds additional layer of security to the data. It is observed that the modified Elgamal supports homomorphic property. The application of homomorphic property in analysing the encrypted data is also discussed and the comparative results with other existing methodologies are stated.

Secure Patient Record Storage in Cloud using Modified Elgamal and Safe Analysis through Homomorphic Property

In this paper, we propose a protocol to evaluate conditional sum on encrypted data. Here, conditional sum is a sort of computation which takes pair of data (ai, di) ∈ A × D (i = 1, 2, ...) and a condition Ã ⊆ A as input and output summation of dis such that corresponding ai satisfies ai ∈ Ã (i.e., Σai∈Ã di.) Such a computation is used in statistical analysis of large scale data. For example, it is used to analyze a total medical cost of employee on their 50s, 40s and 30s. We construct protocols based on additive homomorphic encryption and 2-DNF cryptosystems, respectively, where 2-DNF cryptosystem is a homomorphic cryptosystem which allows arbitrary number of addition and single multiplication on encrypted data. The size of ciphertext for (ai, di) of the proposed schemes protocols on additive homomorphic encryption and 2-DNF encryption are O(n) and O(√n), respectively, where n denotes the cardinality of the set A.

Protocols for evaluating conditional sum on encrypted data.

Automated Trust Negotiation (ATN) is an approach to allow two participants to automatically verify whether their policies are consistent with each other or not. During the negotiation process, in order to protect privacy, both participants intend to disclose their credentials and policies as little as possible. A previous work(ATN)[14] successfully negotiates with perfect privacy preservation where post-negotiation, neither credentials nor policies were revealed to each other. Unfortunately, in order to negotiate with policy with l conjunctive "and" conditions, consisting of m credentials it requires a large computation cost which is linear to combination(??, l). In our work, we focus on this problem and establish a new scheme to lower the cost in the conjunctive condition policy so that our protocol require only ml which can highly decrease computation and communication costs. The proposed scheme performs in semi-honest model. The new idea is adding a dynamic secret key to verify which credentials match with the requested policies. We also demonstrate that this new approach can improve the efficiency of the previous one by showing a qualitative evaluation using implementation and analysis of computation and communication cost.

Improving Efficiency in Privacy-Preserving Automated Trust Negotiation with Conjunctive Policies

We propose a modified ElGamal cryptosystem which can broadcast communicate by encrypting every different plaintext (same plaintext is also acceptable) for plural users, and is also applicable to the systems which have hierarchical structures. And, we show that the security of this cryptosystem is based on difficulties of solving discrete logarithm problems, it maintains equivalent security with the original ElGamal cryptosystem. The transmission efficiency of this cryptosystem is improved.

Modified ElGamal cryptosystem

We propose a modified ElCamal cryptosystem which can broadcast communicate by encrypting every different plaintext (same plaintext is also acceptable) for plural users, and is also applicable to the systems which have hierarchical structures. And, we show that the security of this cryptosystem is based on difficulties of solving discrete logarithm problems , it maintains equivalent security with the original ElGamal cryptosystem. The transmission efficiency of this cryptosystem is improved.

Daisuke Nakamura

Papers

Modified ElGamal cryptosystem

Modified ElGamal Cryptosystem