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3,460 results · page 38 of 145
Mandar Patkar, A.Annamalai giri, Pratik Gite, Akash Shinde · 5 authors
No abstract is available for this record.
Caiqun Shi, Qinlong Huang, Rui Jian, Genghui Chi
The quality of medical services is improved by sharing electronic medical records (EMRs) across multiple medical institutions via cloud edge. However, EMRs contain private information about patients, and cloud servers are untrustworthy, thus they cannot be shared arbitrarily among senders and receivers. Access control encryption (ACE) is a preferred technique that produces encrypted EMRs and then restricts the capabilities of both senders and receivers to enforce the EMR flow via sanitizers. However, existing cross-domain ACE schemes employ a single sender authority to issue encryption keys for senders, which suffers from single point of failure and encryption key escrow that the sender authority can public EMRs arbitrarily. Moreover, they only support coarse-grained access structures such as AND gates, which is not suitable for flexible EMR sharing among medical institutions. To this end, we propose a cross-domain inner-product ACE (CD-IPACE) scheme that features decentralized encryption key generation and fine-grained access structures. Specifically, we construct CD-IPACE from inner-product encryption, threshold structure-preserving signature instantiated with a distributed key generation protocol, and non-interactive zero-knowledge proof, which prevents individual sender authorities from sending ciphertexts, and also protects both data and receiver privacy. Then, we design a secure EMR flow system in cloud edge named ESFlow based on CD-IPACE, which employs edge nodes as sanitizers to check encrypted EMRs and discard illegal ones. Finally, we demonstrate the security and practicality of ESFlow via formal security analysis and extensive experiments.
Fahad F. Alruwaili
<abstract> <p>Ensuring the reliability and trustworthiness of massive IoT-generated data processed in cloud-based systems is paramount for data integrity in IoT-Cloud platforms. The integration of Blockchain (BC) technology, particularly through BC-assisted data Edge Verification combined with a consensus system, utilizes BC's decentralized and immutable nature to secure data at the IoT network's edge. BC has garnered attention across diverse domains like smart agriculture, intellectual property, and finance, where its security features complement technologies such as SDN, AI, and IoT. The choice of a consensus algorithm in BC plays a crucial role and significantly impacts the overall effectiveness of BC solutions, with considerations including PBFT, PoW, PoS, and Ripple in recent years. In this study, I developed a Football Game Algorithm with Deep learning-based Data Edge Verification with a Consensus Approach (FGADL-DEVCA) for BC assisted IoT-cloud platforms. The major drive of the FGADL-DEVCA algorithm was to incorporate BC technology to enable security in the IoT cloud environment, and the DL model could be applied for fault detection efficiently. In the FGADL-DEVCA technique, the IoT devices encompassed considerable decentralized decision-making abilities for reaching an agreement based on the performance of the intrablock transactions. Besides, the FGADL-DEVCA technique exploited deep autoencoder (DAE) for the recognition and classification of faults in the IoT-cloud platform. To boost the fault detection performance of the DAE approach, the FGADL-DEVCA technique applied FGA-based hyperparameter tuning. The experimental result analysis of the FGADL-DEVCA technique was performed concerning distinct metrics. The experimental values demonstrated the betterment of the FGADL-DEVCA approach with other existing methods concerning various aspects.</p> </abstract>
C. Wang, Wei Wu, Fulong Chen, Hong Shu · 9 authors
Blockchain is commonly employed in access control to provide safe medical data exchange because of the characteristics of decentralization, nontamperability, and traceability. Patients share personal health data by granting access rights to users or medical institutions. The major purpose of the existing access control techniques is to identify users who are permitted to access medical data. They hardly ever recognize internal assailants from legitimate entities. Medical data will involve multilayer access within the authorized organizations. Considering the cost of permissions management and the problem of insider malicious node attacks, users hope to implement authorization constraints within the authorized institutions. It can prevent their data from being maliciously disclosed by end‐users from different authorized healthcare domains. For the purpose to achieve the fine‐grained permissions propagation control of medical data in sharing institutions, a trust‐based authorization access control mechanism is suggested in this study. Trust thresholds are assigned to different privileges based on their sensitivity and used to generate zero‐knowledge proof to be broadcasted among blockchain nodes. This method evaluates the trust of each user through the dynamic trust calculation model. And meanwhile, smart contract is employed to verify whether the user’s trust can activate some permissions and ensure the privacy of the user’s trust in the process of authorization verification. In addition, the authorization transaction between users and institutions is recorded on the blockchain for patient traceability and accountability. The feasibility and effectiveness of the scheme are demonstrated through comprehensive comparisons and extensive experiments.
Vishal Sharma, Niranjan Lal, Anand Sharma
Every nation needs a better healthcare system and services for general people for digital medical records, which are available on a large scale. However, patients' health data is too sensitive to share and unsecured to store on centralised storage. However, it is required to ensure security and privacy with better storage and retrieval methods for PEHR (Patient Electronic Health Record). Blockchain allows for the secure and effective exchange of PEHR in a decentralised, tamper-proof manner and traceable distributed ledger that stores using Hyperledger Fabric (HLF) framework in encrypted form on the InterPlanetary File System (IPFS). The hyperledger caliper benchmark measures the blockchain network's performance concerning transaction throughput and latency. This paper discusses the performance evaluation of a Blockchain-Enabled Patient Centric Secure (BEPCS) and privacy preserved electronic health record on IPFS. It proposes a strategy that may increase throughput by 5-10% and decrease latency by 5-10% with better security and privacy.
Maznun Arifa Mohammadan Makhtar, Novia Admodisastro, Mohd Anuar Mat Isa, Daniel Hafiz Abdullah · 5 authors
People are now widely adopting digital assets in various applications, integrating them into almost every aspect of their lives. Electronic books, or e-books, are one of the digital assets that result from the transformation of physical reading material into the digital world. Nowadays, blockchain is used in many industries because it provides immutable and transparent records. E-book publishers may take this opportunity to adopt blockchain technology for e-book data management. However, blockchain storage is limited; thus, storing the e-book files in blockchain is not recommended. A decentralized storage system, such as InterPlanetary Files Systems (IPFS), is an alternative way to store large files like e-books. IPFS can facilitate the storage of e-book files while the metadata is stored in the blockchain. The e-book metadata should be stored in a structured way for effective search and retrieval. E-book metadata could be added, deleted, and updated occasionally. Nevertheless, some data structures often struggle with dynamic collections of records. This paper proposes a linked list-based smart contract on Ethereum that integrates with IPFS for the e-book management system. We demonstrate the implementation of a linked list smart contract for insertion, deletion, update, retrieval, and traversal of the e-book’s metadata. The result shows that a linked list-based smart contract with IPFS could offer a robust solution for e-book data management. This solution provides more opportunities to explore further security and cryptography approaches toward a secure e-book management system.
Sarang Shrikhande
Enhancing the Lightweight Bcrypt Symmetric Key (LBSK) encryption algorithm with a data sensitivity classification system provides a balanced solution to modern cloud-based data security challenges. Today, the ever-increasing reliance on cloud service providers (CSPs) for data encryption has led to organizations facing risks such as vendor lock-in and centralized control over their security infrastructure. This method divides data into groups that are sensitive and non-sensitive in order to address these problems. Sensitive data, which demands higher security, is encrypted using the LBSK Encryption algorithm. Meanwhile, non-sensitive data benefits from the Blowfish Encryption Algorithm. This dual approach ensures encryption strength to data sensitivity, optimizing both security and performance. Sensitive data receives enhanced protection through heavier encryption, ensuring robust security, while non-sensitive data is encrypted more efficiently, reducing computational overheads and improving the overall performance. By managing location of encryption keys and file path on a decentralized Ethereum blockchain, this method also decreases dependency on CSPs and provides more control to the user for its data. The findings suggest that this adaptive encryption strategy achieves noteworthy performance improvements for non-sensitive data, with faster encryption times and reduced resource consumption. At the same time, it maintains high security for sensitive data. This solution effectively balances the need for strong data protection with the efficiency demands of modern cloud computing, providing a flexible and practical approach to managing data encryption based on sensitivity.
Ashis Kumar Samanta, Nabendu Chaki
No abstract is available for this record.
Abylay Satybaldy, Anushka Subedi, Sheikh Mohammad Idrees
No abstract is available for this record.
Phan H. T. Trung, L. K. Bang, N. H. Kha, Tran Quoc Bao · 8 authors
No abstract is available for this record.
Jun Zhao, Kai Zhang, Junqing Gong, Haifeng Qian
Electronic healthcare (E-health) cloud system enables electronic health records (EHRs) sharing and improves efficiency of diagnosis and treatment. In order to address EHRs confidentiality and authorized user access control in E-health cloud, attribute-based proxy re-encryption (ABPRE) has been widely employed which provides dynamic fine-grained access control over encrypted EHRs. Unfortunately, existing ABPRE schemes still have the following defects: 1) capacity of attribute-universe is defined at setup; 2) verifiable mechanism for re-encryption reveals EHRs about patients; 3) traditional access policy reveals sensitive information pertaining to patients. This paper focuses on these issues and presents large-universe, verifiable and privacy-preserving dynamic fine-grained access control scheme for E-health cloud. More details, we solve limitation of attribute-universe to large-universe, which means that attributes aren’t required to be enumerated at setup. Considering disclosure of underlying EHRs in verifiable mechanism, scheme introduces non-interactive zero-knowledge proof as verifiable mechanism that supports public validation and doesn’t leak EHRs of patients. Furthermore, partially hidden policy is employed to protect privacy of patients in policy, which divides attribute into attribute name and attribute value, displaying attribute name and hiding attribute value. Finally, experimental evaluation is given that demonstrates the more comprehensive functionality of our scheme without sacrificing significant computational overhead.
Liam Eagen, Sanket Kanjalkar, Tim Ruffing, Jonas Nick
No abstract is available for this record.
Asma A. Alhussayen, Kamal Jambi, Maher Khemakhem, Fathy Eassa
Blockchain interoperability has become an essential requirement for the advancement of blockchain technology in numerous fields. Enterprise organizations are increasingly utilizing permissioned blockchains to manage and store their organizations’ data and transactions in a private immutable ledger. Interoperability enables permissioned blockchain platforms to communicate and exchange information which is paramount for fully exploiting permissioned blockchains as facilitators for B2B applications. Additionally, the cross-network invocation of smart contracts under agreed conditions enhances business operations. Blockchain oracles can enable permissioned blockchain interoperability and cross-network transactions in a seamless and private manner. However, they have not been studied in the literature as interoperability techniques between permission blockchains. This study proposes a blockchain oracle interoperability technique designed specifically for permissioned blockchain platforms. We presented the architecture of the blockchain oracle interoperability technique and a prototypical implementation to demonstrate the practicality of the proposed technique. In addition, we obtained cross-network transaction latency measurements and analyzed the results.
Fabian Stiehle, Ingo Weber
Process (or workflow) execution on blockchain suffers from limited scalability; specifically, costs in the form of transactions fees are a major limitation for employing traditional public blockchain platforms in practice. Research, so far, has mainly focused on exploring first (Bitcoin) and second-generation (e.g., Ethereum) blockchains for business process enactment. However, since then, novel blockchain systems have been introduced - aimed at tackling many of the problems of previous-generation blockchains. We study such a system, Algorand, from a process execution perspective. Algorand promises low transaction fees and fast finality. However, Algorand's cost structure differs greatly from previous generation blockchains, rendering earlier cost models for blockchain-based process execution non-applicable. We discuss and contrast Algorand's novel cost structure with Ethereum's well-known cost model. To study the impact for process execution, we present a compiler for BPMN Choreographies, with an intermediary layer, which can support multi-platform output, and provide a translation to TEAL contracts, the smart contract language of Algorand. We compare the cost of executing processes on Algorand to previous work as well as traditional cloud computing. In short: they allow vast cost benefits. However, we note a multitude of future research challenges that remain in investigating and comparing such results.
Šeila Bećirović, Irfan Prazina, Damir Pozderac, Razija Turčinhodžić Mulahasanović · 5 authors
Digital credentials represent crucial elements of digital identity on the Internet. Credentials should have specific properties that allow them to achieve privacy-preserving capabilities. One of these properties is selective disclosure, which allows users to disclose only the claims or attributes they must. This paper presents a novel approach to selective disclosure BLS-MT-ZKP that combines existing cryptographic primitives: Boneh-Lynn-Shacham (BLS) signatures, Merkle hash trees (MT) and zero-knowledge proof (ZKP) method called Bulletproofs. Combining these methods, we achieve selective disclosure of claims while conforming to selective disclosure requirements. New requirements are defined based on the definition of selective disclosure and privacy spectrum. Besides selective disclosure, specific use cases for equating digital credentials with paper credentials are achieved. The proposed approach was compared to the existing solutions, and its security, threat, performance and limitation analysis was done. For validation, a proof-of-concept was implemented, and the execution time was measured to demonstrate the practicality and efficiency of the approach.
Ghassan Al-Sumaidaee
The digitization of healthcare presents both opportunities and challenges in managing medical data securely and efficiently. Centralized systems often raise concerns about data security, privacy, and accessibility. Blockchain technology, with its decentralized and transparent framework, offers a potential solution for data exchange and management. However, interoperability limitations between independent blockchain networks restrict their widespread adoption in healthcare. Fragmented data across these systems can lead to duplication, inconsistencies, and compromised patient privacy.This thesis proposes a novel approach using blockchain tokens, specifically non-fungible tokens (NFTs), which are unique digital certificates of ownership recorded on a blockchain, as a universal encrypted access system. These tokens facilitate the seamless transfer of patients' medical data across various blockchain-based healthcare networks. Assigning a unique token to each patient addresses the issues of data fragmentation and lack of interoperability that currently impede healthcare blockchain adoption.To achieve universal access with tokens, our solution leverages distributed storage systems (DSS), a decentralized network approach for data storage, employs steganography, a technique for hiding information within a digital carrier, and integrates cryptographic techniques. DSS eliminates centralized storage of sensitive medical data, thus preventing a single point of failure. To mitigate the inherent vulnerability of public DSS and NFTs metadata, steganography is employed to protect sensitive data, unique identifiers, and critical metadata, thus limiting access to authorized parties. Data is further secured with a password when embedded within images, serving later as NFTs images for simplified data retrieval. Cryptographic methods ensure secure password transfer during patient mobility across networks. Our model leverages the unique properties of NFTs. We use the mutability of NFT data to introduce patient updatable NFTs that can accommodate dynamic medical data. Conversely, the immutability of NFT data establishes an ownership mechanism for patients, ensuring data privacy, uniqueness, and a trusted, sharable protocol. This approach facilitates the seamless integration of new patient records in real-time on the public blockchain. A scoping study on a medical test network assessed the feasibility of using a private blockchain for healthcare records management (HRM). Insights gained led to expanding the scope to two blockchain medical networks. Multiple institutions implemented and tested medical record integration on IPFS within the private network using updatable NFTs on a public blockchain. Performance analysis confirmed the solution's feasibility, effectiveness, and potential for practical application
Tasneem Mirza, Shyren More, Aniket More, Chirag Mahajan
No abstract is available for this record.
Seonghwan Park, Hayoung Kang, Shangze Han, Jonghee M. Youn · 5 authors
A smart contract is a program executed on a blockchain. However, once the smart contract is deployed on the blockchain, it becomes visible to all participants and remains immutable. Thus, any sensitive information or vulnerabilities in smart contracts can be exposed to potential attackers. To protect the confidentiality of smart contracts, existing studies execute smart contracts in a trusted execution environment (TEE). However, they still suffer from vulnerabilities in smart contracts and potential memory-vulnerability problems. If an attack such as privilege escalation occurs by exploiting this vulnerability, the TEE can have a detrimental effect on the entire system as it has the most privileges in the system. To mitigate the memory vulnerability of the smart contracts in TEE, we propose MECAT, a prototype for memory-safe confidential smart contracts. In essence, MECAT runs smart contracts written in Rust, a memory-safe language, in ARM TrustZone. And MECAT is developed as a software library, allowing developers to easily apply MECAT to their smart contracts. According to our evaluation, MECAT only incurs a 1.36x performance overhead and 0.3% power overhead in single-node environments and can process the 16 clients concurrently in the network made with 8 peer nodes.
Ho-Won Lee, Yoon-Young Park, Sungchul Lee, Yoon-Jae Chae
In today’s rapidly evolving digital landscape, ensuring data integrity is paramount for maintaining the security and reliability of applications. This paper introduces the Application Integrity Assurance System (AIAS), a novel solution designed to enhance data integrity through the integration of Ethereum blockchain technology. AIAS leverages smart contracts and the Interplanetary File System (IPFS) to securely store and verify application manifests. By decentralizing the integrity assurance process, AIAS mitigates the risks associated with tampering and unauthorized modifications, providing a robust framework for maintaining data integrity in various application environments. The system has been prototyped and tested on an augmented reality platform, demonstrating its practical application and efficiency. The AIAS framework offers a cost-effective, infrastructure-free solution for safeguarding application integrity, making it an essential tool for platforms that demand high standards of data integrity and security.
Zhanwen Chen
The proposal of the first cryptocurrency Bitcoin brings about the new technology called blockchain that massively expands the concept of financial system.Tamper-resistance, decentralization and traceability are three essential properties of a blockchain.In the following years, the original idea of blockchain also inspired the development and research of other cryptocurrency implementations.And the development of blockchain has extended beyond its fundamental transactional attributes.As blockchain can be regarded as an immutable ledger, it can also be exploited in other application scenarios.Ethereum, based on the principles of blockchain, further introduced smart contract technology, allowing any blockchain user to deploy programs on the chain for others to invoke.This has given rise to decentralized applications.Due to the distinct network model of decentralized applications, existing studies regarding the security of centralized models are difficult to directly adapt to decentralized blockchain applications.Therefore, safeguarding information security and user privacy in the blockchain environment has become a focal point of security study.The thesis contains three studies regarding security of decentralized applications.They are primarily categorized into two types according to the scenarios.One type involves using blockchain to enhance existing applications, while the other focuses on native applications based on blockchain.In the first scenario, I utilize blockchain to provide a verifiable endorsement solution for identity authentication in social networking service (SNS) scenarios.Previous identity authentication research in this area rarely incorporated blockchain.I significantly enhance the reliability and efficiency of identity authentication while preventing impersonation using blockchain.In the second scenario, our focus is on NFT trading within the blockchain.Existing research has only addressed NFT privacy issues to a limited extent due to conflicts with Ethereum's transparency principle.To tackle this problem, I proposed two solutions: first, I make the marketplace a semi-trusted entity to achieve anonymous NFT trading.Then, based on previous research, I further propose a solution for anonymous NFT transactions in a trustless environment.Through security analysis and performance evaluation, our solutions meet security requirements with acceptable expenses, making them suitable for practical applications.
Arusoaie, Andrei, Bărbieru, Claudiu-Nicu, Captarencu, Oana-Otilia, Felber, Pascal · 9 authors
Ethereum is the dominant blockchain ecosystem capable of executing Turing-complete smart contracts. Rollups gained significant traction as the primary layer 2 (L2) solution meant to bring horizontal scalability to the main Ethereum network (L1). A core component of any rollup is the sequencer, which creates new L2 blocks to be submitted in rollup batches to L1. In most of the current rollup architectures, this component is centralised. As a result, these designs are prone to inconspicuous censorship practices by the sequencer. Trusted execution environments (TEEs) can guarantee the integrity of various sequencer components, which is instrumental in addressing censorship. However, the reaction of the system design to censorship attempts depends on where a TEE is integrated and which components it protects. In particular, this reaction is limited in the case of a monolithic TEE-protected sequencer design. Proposer-Builder Separation (PBS) is a non-monolithic paradigm adopted on L1, which separates the production of blocks from proposing them for inclusion in the blockchain. Recently, PBS has been considered for integration with L2 sequencers, with an impact on alleviating censorship. In this paper, we explore the design space of TEE-integrating PBS and non-PBS sequencer variants. First, we introduce a formal framework for the censorship actions that captures the specificity of the L2 sequencer. Then, we analyse to what extent the different designs address these censorship actions. Our main contribution is a novel design variation that allows for a precise observation of censored transactions. In the presence of TEEs, in a PBS setting, we demonstrate this precise observability, which is necessary to enable resilience to censorship.
Mohammed Y. Shakor, Mustafa Ibrahim Khaleel, Mejdl Safran, Sultan Alfarhood · 5 authors
In the rapidly evolving realm of cloud computing security, this paper introduces an innovative solution to address persistent challenges. The proliferation of cloud technology has brought forth heightened concerns regarding data security, necessitating novel approaches to safeguarding sensitive information. The issue centers on the vulnerability of cloud-stored data, often necessitating enhanced encryption and key management strategies. Traditional methods often fall short in mitigating risks associated with compromised encryption keys and centralized key storage. To combat these challenges, our proposed solution encompasses a two-phase approach. In the first phase, dynamic Advanced Encryption Standard (AES) keys are generated, ensuring each file’s encryption with a unique and ever-changing key. This approach significantly enhances file-level security, curtailing an attacker’s ability to decrypt multiple files even if a key is compromised. The second phase introduces blockchain technology, where keys are securely stored with accompanying metadata, bolstering security and data integrity. Elliptic Curve Cryptography (ECC) public key encryption enhances security during transmission and storage, while also facilitating secure file sharing. In conclusion, this comprehensive approach enhances cloud security, providing robust encryption, decentralized key management, and protection against unauthorized access. Its scalability and adaptability make it a valuable asset in contemporary cloud security paradigms, assuring users of data security in the cloud.
Harsh Dixit, Brijesh Kumar Chaurasia, Mr. Nitin Dixit, Naman Bhatia
No abstract is available for this record.
Yusong Yao, Yiwen Shi, Guohua Tian, Meixia Miao · 5 authors
No abstract is available for this record.