Searchable Encryption System Research Articles

Performing Encrypted Cloud Data Keyword Searches Using Blockchain Technology on Smart Devices

Data owners seeking to boost processing power, storage, or bandwidth can take advantage of cloud computing services. However, this shift poses new challenges related to privacy and data security. Searchable Encryption (SE), which combines encryption and search techniques, addresses these issues (violation of data users' privacy) by allowing user data to be encrypted, transmitted to a cloud server, and searched using keywords. Despite its benefits, several recent real-world attacks have raised concerns about the security of searchable encryption. Ensuring forward and backward privacy is likely to become a standard requirement in the development of new SE systems. To address these issues, we propose a scheme that exclusively uses symmetric cryptographic primitives, achieving high communication efficiency and forward and backward privacy. In addition, we emphasize improved I/O efficiency because only the results of subsequent updates are loaded when searching. The time required to retrieve results is so significantly reduced compared to existing SE methods that we have shown that our scheme achieves superior efficiency. Moreover, by integrating blockchain network services with cloud services, we have developed a searchable intelligent cryptosystem suitable for lightweight smart devices. In our study conducted on the Ethereum network, we found our method to be both efficient and secure, especially when compared to methods such as PPSE and Jiang. The results indicate that our system delivers results in terms of performance and privacy within dynamic cloud environments making it a solution for protecting confidential information.

Researching basic searchable encryption schemes in databases that support SQL

Currently, many users prefer to outsource data to third-party cloud servers in order to mitigate the load of local storage. However, storing sensitive data on remote servers creates security challenges and is a source of concern for data owners. With ever-growing security and privacy concerns, it is becoming increasingly important to encrypt data stored remotely. However, the use of traditional encryption prevents the search operation in the encrypted data. One approach to solving this problem is searchable encryption. Solutions for search in secure databases cover a wide range of cryptographic techniques, although there is still no dominant solution. Designing secure search systems is a balance between security, functionality, performance, and usability. Therefore, this paper provides an overview of some of the important current secure search solutions. The main searchable encryption systems of databases that support SQL are considered. The strengths and weaknesses of the analyzed systems and the techniques implemented in them are highlighted. A comparative analysis of some characteristics of the compared systems is given. Attention is drawn to the fact that the ability to perform search operations in encrypted data leads to a complication of systems, an increase in the amount of required memory and query execution time. All this indicates the openness of the protected search problem and the need for further research in this direction to ensure secure work with remote databases and data warehouses.

A Blockchain-Based Normalized Searchable Encryption System for Medical Data

As COVID-19 continues to spread around the world, the healthcare industry has accelerated the transformation to digital healthcare services. In the era of big data, many hospitals prefer to use remote cloud servers to store and manage massive electronic medical data. However, cloud-assisted medical data systems cannot guarantee the confidentiality, integrity, and availability of data. Searchable encryption can effectively address the above challenges by enabling data search on the ciphertext, which achieves the availability of medical data while ensuring data security and privacy. However, the search server may return mismatched search results due to economic interests or single points of failure. Blockchain is a decentralized computing paradigm with public verifiability, which provides an efficient solution to this problem. However, the existing blockchain-based searchable encryption solutions do not consider the flexible search function of multiple users and the restriction of encrypted data for medical scenarios. Therefore, we propose a blockchain-based multiuser normalized searchable encryption (BNSE) scheme and design a blockchain-based normalized searchable encryption system for medical data (BNSEM) based on the scheme. To verify the practicality of the system, we evaluate the performance from both theoretical and experimental aspects.

Flexible Wildcard Searchable Encryption System

Searchable Encryption is a cryptographic technique which allows search of data in an encrypted format. This technique provides user data confidentiality insurance for public cloud storage service as well as allows multiple keyword search over encrypted data. Previously existing systems provide exact or fuzzy keyword search which corrects spelling errors only and their features are limited. In this paper, we propose a system known as adaptable wildcard searchable encryption system which allows mu.

A novel searchable encryption scheme to reduce the access pattern leakage

Searchable symmetric encryption (SSE) is a technology that enables clients to outsource sensitive data in the cloud. The vast usage of cloud and rapid growth in file sharing over the cloud has forced researchers into devising newer searchable encryption (SE) systems that are more secure and robust. This paper explores the effects of leakage of access patterns to an adversary. It is observed that in most of the existing systems, a successful statistical attack can help the adversary learn the access pattern, provide him with the required document and reveal the underlying data. This paper addresses these issues by presenting a novel SE system which hides the search pattern and access pattern. In this paper, we propose a SSE system that uses forward index while lifting the one-time search limitation of the previous solutions. Our system uses a trapdoor obfuscation technique to deceive the 3rd party adversary who is considered as an active entity other than client and server, observing the information being exchanged during the active session of client and the cloud service provider. Compared with the existing techniques, this solution uses keyword analysis to extract limited words from the documents based on the frequency of occurrence. To provide stronger privacy, an encoding technique is used which aims to hide the access pattern from the adversary. In order to eliminate trapdoor linkability, a probabilistic trapdoor generation process is presented. The test results demonstrate that our system is suitable for practical usage with minimal overhead and is more efficient as compared to the state of the art.

A Searchable Encryption Scheme with Biometric Authentication and Authorization for Cloud Environments

Cloud computing offers the possibility of providing suitable access within a network for a set of resources. Many users use different services for outsourcing their data within the cloud, saving and mitigating the local storage and other resources involved. One of the biggest concerns is represented by storing sensitive data on remote servers, which can be found to be extremely challenging within different situations related to privacy. Searchable Encryption (SE) represents a particular case of Fully Homomorphic Encryption (FHE) and at the same time represents a method composed from a set of algorithms meant to offer protection for users’ sensitive data, while it preserves the searching functionality on the server-side. There are two main types of SE: Searchable Symmetric Encryption (SSE), where the ciphertexts and trapdoors for searching are performed using private key holders, and Public Key Searchable Encryption (PKSE), in which a specific number of users have the public key based on which are capable of outputting ciphertexts and giving the possibility of producing the trapdoors by using the private key from the holder. In this article, we propose a searchable encryption system that uses biometric authentication. Additionally, biometric data are used in the trapdoor generation process, such that an unauthorized user cannot submit search queries. The proposed system contains three components: classic user authentication (based on username, password, and a message with a code using short message service (SMS), biometric authentication, and the searchable encryption scheme. The first two components can be seen as two-factor authentication (2FA), and the second component represents the initialization step of the searchable encryption scheme. In the end, we show and demonstrate that the proposed scheme can be implemented with success for medium to complex network infrastructures. We have granted special attention to the trapdoor function, which generates a value that can be used to perform the search process and search function that is based on the trapdoor pair for searching within the index structure. We provide the correctness and security proof of the operations, which gives us the guarantee that the cloud servers return the correct documents. Additionally, we discuss measuring the performance of the authentication scheme in terms of performance indicators, introducing two indicators for measuring purposes—namely, cloud average number of non-legitim the user actions for cloud purposes (CANNL) and cloud average number of legitim user actionsCANLU.

Secure and Practical Wildcard Searchable Encryption System Based on Inner Product

As cloud computing is widely used in a variety of different applications, how to continuously improve the efficiency of processing data while protecting data privacy and security is still a problem worth investigating. Existing searchable encryption schemes mainly focus on the exact matching patterns, which are insufficient to meet and cope with the increasing demands for fuzzy search. In particular, there has been a lack of attention to the research on practical and privacy-preserving fully wildcard searchable encryption. In this article, we propose a new wildcard searchable encryption system, which is built based on a novel inner product encryption scheme that can address the above challenges simultaneously. A two-dimensional inner product relation is introduced to remove all restrictions on wildcards, allowing our system to support fully wildcard search. To resist active attacks from malicious adversaries and prevent information leakage, we enhance the security to adaptive simulation-based security under the SXDH assumption. The corresponding security proof of our construction is implicitly established on a hash proof system. Our elaborately constructed system removes redundant parameters and extra complex computations, ensuring its practicality and efficiency. Finally, our system shows better performance in more than 86% of cases in the conducted experiments.

A novel security mechanism using AES cryptography approach in cloud computing

SummaryFor a smart cloud computing system, security and privacy are the required factors. In recent days, the evolvement of cloud technology is immense, according to which several cloud service providers (CSPs) evolved. Each CSP has its infrastructure with its security policies. Even though still the security in cloud computing is an existing challenge, it is more important to maintain the trustiness of cloud environment among the cloud users. On this motto, we propose a novel tailored—advanced encryption standard (AES) Cryptographic Algorithm (TCA). AES is one of the popular cryptography algorithms. We indulged in increasing the performance of this algorithm by minimizing the time taken for the cryptography process. Here, the cryptography is processed with AES algorithm. In order to improve the efficiency of AES, a concept of a chunk file system is introduced. The input file is chunked into multiple which facilitates quick and effective encryption. To prove the efficiency of our proposed system, a comparison work is carried out with the existing algorithms lightweight keyword searchable encryption (LFSE) and cloud key management system (CKMS). The comparison work is based on the aspect of time taken during key generation, encryption and decryption. The obtained result is plotted, and comparison output clearly states our TCA's excellence in the aspect of efficiency compared to others.

Flexible Wildcard Searchable Encryption System

Searchable encryption is an important technique for public cloud storage service to provide user data confidentiality protection and at the same time allow users performing keyword search over their encrypted data. Previous schemes only deal with exact or fuzzy keyword search to correct some spelling errors. In this paper, we propose a new wildcard searchable encryption system to support wildcard keyword queries which has several highly desirable features. First, our system allows multiple keywords search in which any queried keyword may contain zero, one or two wildcards, and a wildcard may appear in any position of a keyword and represent any number of symbols. Second, it supports simultaneous search on multiple data owner's data using only one trapdoor. Third, it provides flexible user authorization and revocation to effectively manage search and decryption privileges. Fourth, it is constructed based on homomorphic encryption rather than Bloom filter and hence completely eliminates the false probability caused by Bloom filter. Finally, it achieves a high level of privacy protection since matching results are unknown to the cloud server in the test phase. The proposed system is thoroughly analyzed and is proved secure. Extensive experimental results indicate that our system is efficient compared with other existing wildcard searchable encryption schemes in the public key setting.

File-Centric Multi-Key Aggregate Keyword Searchable Encryption for Industrial Internet of Things

Cloud storage has been used to reduce the cost and support convenient collaborations for industrial Internet of things (IIoT) data management. When data owners share IIoT data with authorized parties for data interaction, secure cloud data searching and file access control are fundamental security requirements. In this paper, first we discuss a new insider attack to the Cui's multi-key aggregate searchable encryption scheme, where the unauthorized inside users can guess the other users private keys. Then, we propose a novel file-centric multi-key aggregate keyword searchable encryption (Fc-MKA-KSE) system for the IIoT data in the file-centric framework. Specifically, we present two formal security models, namely, the security models of the indistinguishable selective-file chosen keyword attack and the indistinguishable selective-file keyword guessing attack, which can satisfy the security requirements. Our experimental results show that the proposed scheme achieves computational efficiency.

Expressive query over outsourced encrypted data

Data security and privacy concerns in cloud storage services compel data owners to encrypt their sensitive data before outsourcing. Standard encryption systems, however, hinder users from issuing search queries on encrypted data. Though various systems for search over encrypted data have been proposed in the literature, existing systems use different encrypted index structures to conduct search on different search query patterns and hence are not compatible with each other. In this paper, we propose a query over encrypted data system which supports expressive search query patterns, such as single/conjunctive keyword query, range query, boolean query and mixed boolean query, all using a single encrypted index structure. To the best of our knowledge, the proposed system enables the most expressive query pattern search among all the existing solutions. In addition, the system allows data users to simultaneously query over encrypted documents from multiple data owners using one query trapdoor and supports flexible user authorization and revocation. We show that our system is secure and resists keyword guessing attack. We also conduct extensive experiments and demonstrate that the system is more efficient than other public key searchable encryption systems.

Improved Searchable Encryption via Conglomerate Keys in Federated Cloud Storage

Objectives: Cloud computing is the sort of computing process that shares the data and its resources in the Internet. Data Leakage is the main challenge prevails in the federated cloud storage service. This challenge is overcome by proposing an efficient searchable encryption system. Methodology: An improved searchable encryption is designed to apportion the data among the multi-users. An efficient key management is the required phase of the encryption schemes. Owing to adversaries, a promising approach using conglomerate keys invents as a better searchable encryption schemes in multiowner applications. Findings: By reducing the count of trapdoor function to cloud data from the multi-user, an effective search over the encrypted data is performed. In compare to existing models, tree based approach and one to one function, the proposed, improved SE-CK works efficient in terms of lessened delegation ratio and conglomerate keys. Applications/ Improvements: This method can also be extended to the hybrid architecture like Indexing schemes, Re-encryption schemes etc.

Design of City Logging System using Searchable Image Encryption System of Streaming Service

In this paper, we propose a city-logging system to collect various types of data around the roads using mobile observation equipment. Since the collected image data from CCTV contains several things which can violate someone’s privacy, we present a secure method to search CCTV image using searchable image encryption system. In addition, we illustrate a city-info service which can be provided by analyzing the collected data. Implementation and testing of the proposed system will be carried out in future.

Privacy preserving revocable predicate encryption revisited

AbstractPredicate encryption (PE) that provides both the access control of ciphertexts and the privacy of ciphertexts is a new paradigm of public‐key encryption. An important application of PE is a searchable encryption system in cloud storage, where it enables a client to securely outsource the search of a keyword on encrypted data without revealing the keyword to the cloud server. One practical issue of PE is to devise an efficient revocation method to revoke a user when the secret key of the user is compromised. Privacy preserving revocable PE (RPE) can provide not only revocation but also the privacy of revoked users. In this paper, we first define two new security models of privacy preserving RPE: the strongly full‐hiding (FH) security and the weakly FH security. Next, we propose a general RPE construction from any PE scheme and prove its security in the weakly FH security model. Our generic RPE scheme is efficient because the number of ciphertext elements is not proportional to the number of users in a receiver set. Additionally, our RPE scheme can support polynomial‐size circuits if a recently proposed functional encryption scheme for polynomial‐size circuits is used as an underlying PE scheme. Copyright © 2014 John Wiley & Sons, Ltd.

소수테이블을 이용한 실용적인 다중 키워드 검색가능 암호시스템

ABSTRACT Searchable encryption systems provide search on encrypted data while preserving the privacy of the data and the search keywords used in queries. Recently, interest on data outsourcin g has increased due to proliferation of cloud computing service s. Many researches are on going to minimize the trust put on exter nal servers and searchable encryption is one of them. However, most of previous searchable encryption schemes provide only a single keyword boolean search. Although, there have been proposals to provide conjunctive keyword search, most of t hese works use a fixed field which limit their application. In this paper, we propose a field-free conjunctive keyword searcha ble encryption that also provides rank information of search results. Our system uses prime tables and greatest common divisor operation, making our system very efficient. Moreover, our system is practical and can be implemented very easily since it does not require sophisticated cryptographic module. Keywords: searchable encryption, conjunctive keyword search, rank, prim e table접수일(2013년 7월 5일), 수정일(2013년 11월 19일), 게재확정일(2013년 12월 3일)†주저자, sunyujin@koreatech.ac.kr‡교신저자, sangjin@koreatech.ac.kr (Corresponding author)

Secure Data Management Scheme using One-Time Trapdoor on Cloud Storage Environment

Because of the development of network and computing technology, cloud computing systems, which remotely store data in a third place and retrieves and processes these data with diverse terminals anytime and anywhere, have attracted considerable research attention. If an individual’s sensitive information or information about his/her body is stored as data stored in a cloud with remote storage without encryption, then an attacker or unethical server manager can access these stored data without the permission of the data owner. This is a security problem. Therefore, data stored using remote storage, need to be encrypted. However, in the case of data encrypted using a general encryption algorithm, since the entire set of encrypted data is downloaded to the data owner’s terminal for a safe search and has to be decrypted for the search, the advantages of remote storage are nullified. To solve this problem, searchable encryption systems have been developed. With a searchable encryption system, encrypted data can be searched safely without the process of decryption. This scheme safely stores the index that can search data and enables search with no information spill. However, the existing scheme, which is available for search, produces the same form of trapdoor for multiple searches of a keyword. A number of queries are transferred to the cloud, and the storage manager infers the keyword through these queries. The fact that the information user searches and the searched data content can be figured out through the queries poses a significant problem. Therefore, this research paper suggests a safe scheme for data management by using a one-time trapdoor so that an unethical server manager or attacker cannot infer the content of the search and the data through the queries when the same user searches the same keyword. This is possible because different trapdoors are produced when the same user searches the same keyword.

검색가능 암호시스템을 위한 데이터 암호기법의 문제점 분석

클라우드 컴퓨팅의 보급으로 최근 데이터 아웃소싱에 대한 요구가 매우 높아지고 있다. 하지만 클라우드 컴퓨팅의 근본적인 걱정인 외부 서버 신뢰 문제에 대한 만족할만한 수준의 해결책이 아직 제시되고 있지 못하다. 이 때문에 검색가능 암호화에 대한 연구가 최근에 다시 활발해지고 있다. 하지만 검색 기능에 대한 연구에만 집중되어 중요한 요소 중 하나인 데이터 암호메커니즘에 대한 연구는 상대적으로 소홀히 되고 있다. 적절한 암호메커니즘의 적용 없이는 검색가능 암호화를 실제 서버에 적용하는 것이 불가능하다. 이 논문에서는 다중 사용자가 이용하는 검색가능 암호시스템에서 지금까지 제안된 데이터 암호메커니즘과 사용 가능한 메커니즘들을 분석하여 그들의 장단점을 논한다. 분석 결과 논문에서 고려한 브로드캐스트 암호 기법, 속성기반 암호 기법, 프록시 재암호화 기법은 모두 적절한 해결책이 되지 못한다. 현존하는 기법들의 가장 큰 문제는 별도의 완전히 신뢰할 수 있는 서버가 필요하다는 것과 외부 사용자와 완전히 신뢰하지 못하는 서버 간 공모 공격을 방지할 수 없다는 것이다.

Design of Searchable Image Encryption System of Streaming Media based on Cloud Computing

In this paper, we design searchable image encryption system to provide the privacy and authentication on streaming media based on cloud computing. The searchable encryption system is the matrix of searchable image encryption system by extending the streaming search from text search, the search of the streaming service is available, and supports personal privacy and authentication using encryption/decryption and CBIR technique. In simple simulation of post-cut and image keyword creation, we can verify the possibilities of the searchable image encryption system based on streaming service.

원격 저장소 환경에서 다중 키워드를 이용한 효율적인 검색 가능한 대칭키 암호 시스템

매우 가벼운 무게와 손안에 들어가는 작은 크기로 휴대성을 제공하는 휴대용 저장매체는 사용자들로부터 많은 호응을 받고 있다. 하지만 휴대용 저장매체의 휴대성으로 인하여 USB 메모리의 분실 및 도난이 잦아졌고 그로 인하여 저장매체 내부에 저장되어 있는 개인정보가 유출되는 사고가 발생하는 문제점이 발생되었다. 따라서 분실위험이 없고 네트워크를 통하여 언제든 자료를 저장하고 접근할 수 있는 원격 저장소 서비스가 등장하게 되었다. 정보통신산업이 발달함에 따라 여러 종류의 정보 기기를 통하여 언제 어디서든 빠른 네트워크에 접근할 수 있게 되었고, 이는 원격 저장소를 이용하는 사용자들을 더욱 증가하게 하였다. 하지만 여러 사용자의 주요 자료가 저장됨에 따라 비윤리적인 관리자 및 공격자로 인하여 서버에 저장된 여러 사용자의 주요자료가 동시에 유출될 수 있는 위험이 존재한다. 이를 해결하기 위해 서버에 저장되는 자료의 암호화가 필요해졌으며, 이와 동시에 암호화한 자료의 효율적인 검색 및 이용을 위하여 검색 가능 암호 시스템이 필요하다. 하지만, 기존의 대칭키 검색 가능 암호 시스템은 문서의 삽입/삭제 효율성 및 다중 키워드 검색 시 연산의 효율성이 떨어지는 문제점이 존재한다. 따라서 본 논문은 기존 대칭키 검색 가능 암호의 문제점을 해결할 수 있는 효율적인 대칭키 검색 가능 암호 시스템을 제안한다. Removable Storage provides the excellent portability with light weight and small size which fits in one's hand, many users have recently turned attention to the high-capacity products. However, due to the easy of portability for Removable Storage, Removable Storage are frequently lost and stolen and then many problems have been occurred such as the leaking of private information to the public. The advent of remote storage services where data is stored throughout the network, has allowed an increasing number of users to access data. The main data of many users is stored together on remote storage, but this has the problem of disclosure by an unethical administrator or attacker. To solve this problem, the encryption of data stored on the server has become necessary, and a searchable encryption system is needed for efficient retrieval of encrypted data. However, the existing searchable encryption system has the problem of low efficiency of document insert/delete operations and multi-keyword search. In this paper, an efficient searchable encryption system is proposed.