Ciphertext-policy Attribute-based Encryption Algorithm Research Articles

Institutional innovation essence and knowledge innovation goal of intellectual property law in the big data era

This work aims to expand the understanding on the nature of institutional innovation and the goal of knowledge innovation of intellectual property (IP) law in the era of big data (BD) and to avoid the risks of information security in the IP service system. On the basis of the era of BD, the nature of institutional innovation and the goal of knowledge innovation in IP law are systematically discussed. Combined with smart contract (SC) technology, an IP service system based on blockchain technology is designed to ensure the security of IP services. The SC is optimized from the perspective of concurrency, and the contract transactions (CTs) are clustered. Moreover, considering the execution time (ET) and available resources of CTs, a speculative concurrency control algorithm that can realize intelligent contract scheduling is proposed. On the basis of the ciphertext-policy attribute-based encryption (CP-ABE) algorithm, a policy-updatable attribute encryption algorithm is designed. The improved CP-ABE algorithm includes six steps: system initialization, attribute private key generation, encryption, decryption, ciphertext policy generation, and ciphertext policy update. The identity parameter of the traceability manager is introduced into the improved CP-ABE scheme, which significantly increases the amount of computation of bilinear mapping, thus resulting in the time cost of encryption and decryption being approximately 350 ms and 300 ms higher than that of the CP-ABE scheme. Using the technical mode of “blockchain + SC,” the design of the IP service system is realized, which has important reference value for the institutional innovation of IP law.

An Efficient Encryption Scheme with Fully Hidden Access Policy for Medical Data

With the development of informatization, patient medical data are generally stored in the form of electronic medical records. Hospitals store a large amount of medical data on cloud servers, which can ensure the integrity and sharing of medical data. There are many problems when sharing medical data, the most important of which is the security of private data. The ciphertext-policy attribute-based encryption (CP-ABE) algorithm not only supports data encryption, but also supports data access control. The CP-ABE algorithm is applied to medical databases. Through the encryption of medical data and the fine-grained control of data owner access to medical data, the privacy security and sharing security of medical data are realized. However, the traditional CP-ABE algorithm also has problems for the data user regarding access policy privacy leakage and the low efficiency of medical data encryption and decryption. This paper proposes a secure and efficient encryption technique. Medical data are encrypted using a symmetric encryption algorithm, and the CP-ABE algorithm with a fully hidden access policy encrypts the symmetric key. To implement access policy hiding, it uses an attribute bloom filter (ABF) for all access structures. The solution also supports the outsourced decryption of medical data, which can improve the encryption and decryption efficiency of the technique. Finally, in this paper, it is demonstrated that the scheme is selectively chosen-plaintext attack secure (CPA-secure). The experimental results show that users have less computational consumption to obtain medical data.

Lattices-Inspired CP-ABE from LWE Scheme for Data Access and Sharing Based on Blockchain

To address the quantum attacks on number theory-based ciphertext policy attribute-based encryption (CP-ABE), and to avoid private key leakage problems by relying on a trustworthy central authority, we propose a lattice-inspired CP-ABE scheme for data access and sharing based on blockchain in this paper. Firstly, a CP-ABE-based algorithm using learning with errors (LWE) assumption is constructed, which is selective security under linear independence restriction in the random oracle model. Secondly, the blockchain nodes can act as a distributed key management server to offer control over master keys used to generate private keys for different data users that reflect their attributes through launching transactions on the blockchain system. Finally, we develop smart contracts for proving the correctness of proxy re-encryption (PRE) and provide auditability for the whole data-sharing process. Compared with the traditional CP-ABE algorithm, the post-quantum CP-ABE algorithm can significantly improve the computation speed according to the result of the functional and experimental analysis. Moreover, the proposed blockchain-based CP-ABE scheme provides not only multi-cryptography collaboration to enhance the security of data access and sharing but also reduces average transaction response time and throughput.

Kerberos based Authentication for healthcare application (KAHA) in IoT WBAN

As a result of the fast development of technology, healthcare systems have rapidly morphed into an all-pervasive environment that is replete with a variety of difficulties and possibilities. Threats and assaults with severe societal effects have been launched due to the increasing popularity of WBANs and their features and applications. The data is encrypted using a Ciphertext-Policy Attribute-Based Encryption algorithm and signed at the data sink in Secure and Efficient data transfer protocol, guaranteeing the data’s safety at all times. The computational cost and complexity to solve this issue string are both raised by this technique. Security code that the public may access In WBAN, cryptography allows Kerberos-based authentication. Public-key cryptography can be used to secure the initial authentication procedure. The procedure’s goal is to let the user safely send the required certificate (including the TGT and session key) to the sensor. The simulation results demonstrate that this approach improved the detection ratio, and minimized the false positive ratio compared to the baseline protocol in the network.

Blockchain Merkle-Tree Ethereum Approach in Enterprise Multitenant Cloud燛nvironment

This research paper puts emphasis on using cloud computing with Blockchain (BC) to improve the security and privacy in a cloud. The security of data is not guaranteed as there is always a risk of leakage of users’ data. Blockchain can be used in a multi-tenant cloud environment (MTCE) to improve the security of data, as it is a decentralized approach. Data is saved in unaltered form. Also, Blockchain is not owned by a single organization. The encryption process can be done using a Homomorphic encryption (HE) algorithm along with hashing technique, hereby allowing computations on encrypted data without the need for decryption. This research paper is composed of four objectives: Analysis of cloud security using Blockchain technology; Exceptional scenario of Blockchain architecture in an enterprise-level MTCE; Implementation of cipher-text policy attribute-based encryption (CP-ABE) algorithm; Implementation of Merkle tree using Ethereum (MTuE) in a Multi-tenant system. Out of these four objectives, the main focus is on the implementation of CP-ABE algorithm. CP-ABE parameters are proposed for different levels of tenants. The levels include inner tenant, outer tenant, Inner-Outer-Tenant, Inner-Outer-External-Tenant, Outer-Inner-Tenant, External-Outer-Inner-Tenant and the parameters such as token, private key, public key, access tree, message, attribute set, node-level, cipher-text, salting which will help in providing better security using CP-ABE algorithm in a multi-tenant environment (MTE) where tenants can be provided with different levels of security and achieved 92 percentage of authenticity and access-control of the data.

A privacy preserving CP-ABE-based access control on data sharing in VANETs

Vehicle ad hoc networks (VANETs) enable fast interconnection between vehicles and roadside infrastructure to ensure stable and continuous network services for vehicles. Data sharing, as the primary service of MANET, not only ensures vehicles can access the required information but also supports vehicles in sharing the required information with other vehicles to provide a better travel experience for drivers and passengers. However, without an effective access control scheme to protect data security, the adversaries can collect data transmitted by other vehicles during data sharing and threaten VANET's security by sending fake data. In order to address the current data-sharing scheme for vehicles that collects information from the environment with low efficiency, high maintenance cost and ineffective access control schemes, a secure and effective data-sharing scheme is proposed in this paper by improving the ciphertext policy attribute-based encryption algorithm (CP-ABE). Performance analysis and simulation experiments show that the scheme can achieve secure and efficient data sharing and enhance the driving experience. When the number of attributes is 20, the computational overhead of our scheme in the encryption phase is 3.18% of the compared scheme, while the computational overhead in the decryption phase is 44% of the compared scheme.

Cloud Storage Data Access Control Scheme Based on Blockchain and Attribute-Based Encryption

Cloud storage is a popular model of the application in various fields, and the security of storage data and access permission have been widely considered. Attribute-based encryption (ABE) provides fine-grained user access control and ensures data confidentiality. However, current ABE access control schemes rely on trusted cloud servers and provide a low level of security. To solve these problems of traditional encryption schemes, we propose a blockchain-based and ABE cloud storage data access control scheme. In this article, blockchain and smart contract technology are the core elements to ensure data integrity and build a decentralized verification method for outsourcing results. This application can minimize the reliance on servers in the cloud environment. Based on the ciphertext-policy ABE algorithm, the proposed scheme supports a hidden access policy to avoid the risk of privacy leakage. In addition, we adopt outsourcing technology and predetected decryption algorithms to reduce the computational overhead of local and outsourced servers. Security analysis and performance evaluation show that our proposed scheme has high computational efficiency and satisfies the condition of indistinguishability under the chosen-ciphertext attacks.

A Novel Blockchain-Based Encryption Model to Protect Fog Nodes from Behaviors of Malicious Nodes

The world has experienced a huge advancement in computing technology. People prefer outsourcing their confidential data for storage and processing in cloud computing because of the auspicious services provided by cloud service providers. As promising as this paradigm is, it creates issues, including everything from data security to time latency with data computation and delivery to end-users. In response to these challenges, the fog computing paradigm was proposed as an extension of cloud computing to overcome the time latency and communication overhead and to bring computing and storage resources close to both the ground and the end-users. However, fog computing inherits the same security and privacy challenges encountered by traditional cloud computing. This paper proposed a fine-grained data access control approach by integrating the ciphertext policy attribute-based encryption (CP-ABE) algorithm and blockchain technology to secure end-users’ data security against rogue fog nodes in case a compromised fog node is ousted. In this approach, we proposed federations of fog nodes that share the same attributes, such as services and locations. The fog federation concept minimizes the time latency and communication overhead between fog nodes and cloud servers. Furthermore, the blockchain idea and the CP-ABE algorithm integration allow for fog nodes within the same fog federation to conduct a distributed authorization process. Besides that, to address time latency and communication overhead issues, we equip each fog node with an off-chain database to store the most frequently accessed data files for a particular time, as well as an on-chain access control policies table (on-chain files tracking table) that must be protected from tampering by rogue fog nodes. As a result, the blockchain plays a critical role here because it is tamper-proof by nature. We assess our approach’s efficiency and feasibility by conducting a simulation and analyzing its security and performance.

SECURED DATA RETRIEVAL IN MILITARY APPLICATIONS USING CP-ABE

Disruption-tolerant network (DTN) technologies are only solutions for military environment because of their mobile nodes irregular network connectivity and frequent partitions. But due to its nature of having external storage node during the transmission there is chance of getting exploited. Cipher text-policy attribute-based encryption(CP-ABE), is a good solution however, the problem of applying CP-ABE in decentralized DTNs introduces several security and privacy challenges with regard to the attribute revocation, key escrow, and coordination of attributes issued from different authorities.Some users (receivers) may change their associated attributes at some point (for example moving their region) here there is a need of attribute updation and also provides forward and backward secrecy for the attribute revocation problem. So we proposed a system that provides a multi authority CP-ABE scheme for secure data retrieval in decentralized DTNs a variation of the CP-ABE algorithm that overcomes the attribute revocation problem.

APPLSS: Adaptive privacy preserved location sharing scheme based on attribute-based encryption

Unauthorized access to location information in location-based service is one of the most critical security threats to mobile Internet. In order to solve the problem of quality of location sharing while keeping privacy preserved, adaptive privacy preserved location sharing scheme called APPLSS is proposed, which is based on a new hierarchical ciphertext-policy attribute-based encryption algorithm. In the algorithm, attribute authority sets the attribute vector according to the attribute tags of registration from the location service providers. Then the attribute vector can be adaptively transformed into an access structure to control the encryption and decryption. The APPLSS offers a natural hierarchical mechanism in protecting location information when partially sharing it in mobile networks. It allows service providers access to end user's sensitive location more flexibly, and satisfies a sufficient-but-no-more strategy. For end-users, the quality of service is obtained while no extra location privacy is leaked. To improve service response performance, outsourced decryption is deployed to avoid the bottlenecks of the service providers and location information providers. The performance analysis and experiments show that APPLSS is an efficient and practical location sharing scheme.

Efficient and Secure Attribute-Based Access Control With Identical Sub-Policies Frequently Used in Cloud Storage

Under the assumption of honest-but-curious cloud service provider, various cryptographic techniques have been used to address the issues of data access control and confidentiality in public cloud storage. Among which, attribute-based encryption (ABE) has been shown to be an attractive scheme. Although the technique of ABE brings in various benefits, its onerous overhead should not be ignored. In this article, based on an improved LSSS (linear secret sharing scheme) matrix expression integrated in CP-ABE (Ciphertext-Policy Attribute-Based Encryption) algorithm, we present an efficient and secure attribute-based access control scheme for the scenarios where multiple data are shared and encrypted with frequently used sub-policies. In the scheme, a user can store the parameters about a specific sub-policy in his/her first decryption, which can be reused in the subsequent data decryptions whose embedded access policies include the same sub-policy so as to significantly reduce the computation cost. Our proposed scheme is proved to be semantically secure under chosen plaintext attacks and can well preserve the confidentiality of the data sharing system. Our analysis and experimentation also show that our scheme does significantly reduce the decryption time and while trades in only very little storage overhead, and thus effectively promotes the efficiency.

An enhanced media ciphertext-policy attribute-based encryption algorithm on media cloud

With the development of cloud computing, more and more video services are moving to the cloud. How to realize fine-grained access control of those data on cloud becomes an urgent problem. Attribute-based encryption provides a solution. However, heavy computation is still a bottleneck restricting the wider application of attribute-based encryption in cloud computing. In addition, we find that expression of the access control structure on media cloud can be further improved. To solve these problems, we propose an enhanced media ciphertext-policy attribute-based encryption algorithm and introduce its two key components, the multiple access tree and the key chain. To increase the scalability of the proposed algorithm, we discussed the issues of multi-authorization, user revocation, and 1 − n multiple access tree. Security analysis shows that enhanced media ciphertext-policy attribute-based encryption can successfully resist chosen-plaintext attacks under the decisional bilinear Diffie–Hellman assumption. Performance analysis proves both theoretically and practically that the proposed algorithm incurs less computational cost than the traditional ciphertext-policy attribute-based encryption, multi-message ciphertext-policy attribute-based encryption, and scalable ciphertext-policy attribute-based encryption by optimizing the access control structure. Our proposed algorithm has strong practical significance in media cloud.

SSPA-LBS: Scalable and Social-Friendly Privacy-Aware Location-Based Services

Privacy-aware location-based service (PA-LBS) preserves LBS users’ privacy but undesirably sacrifices service quality. In order to balance the two factors with satisfactory user experience, existing frameworks are faced with two barriers, that is, scalability and social-friendliness. First, existing schemes do not enable LBS users to flexibly scale their privacy level on service provision. Such a lack of scalability easily results in either unacceptable service-quality degradation or insufficient privacy protection and fails to meet dynamic user requirements. Second, existing schemes handle privacy protection by merely considering the trust relationship between users and servers but ignore the complex trust relationships among users. As a result, users cannot preserve privacy in location-based social services that involve user-to-user interactions. In this paper, we present the first scalable and social-friendly PA-LBS system. In particular, we propose a novel camouflage algorithm with a formal privacy guarantee that enables LBS users to expose their location information by scaling two privacy related factors, that is, camouflage range and place type. Furthermore, we apply the scalable ciphertext policy attribute-based encryption algorithm to enable LBS users to effectively control the access from other users to their location information. Moreover, we also demonstrated the operational efficiency of the proposed system through successful implementations on Android devices.

CONCEPTUAL FRAMEWORK FOR LIGHTWEIGHT CIPHERTEXT POLICY-ATTRIBUTE BASED ENCRYPTION SCHEME FOR INTERNET OF THINGS DEVICES

The purpose of this paper is to propose a conceptual model for data security in the Internet of thing devices. Estimated by Jumoki in early 2018 to 2022, there will be about 18 billion connected IoT devices. Therefore many issue related to IoT devices were discussed especially data security. Cryptography with lightweight features is one of the focus area by researchers to develop a powerful cryptography scheme for IoT devices. Lightweight cryptography scheme has been discussed and proposed widely recently. There are AES, PRESENT, Hash algorithm declared as a lightweight algorithm under consideration in ISO/IEC 29192 “Lightweight Cryptography”. Unfortunately these lightweight algorithm is one-to-one communication cryptography technique. This algorithm is very practical to implement for individuals or for small group communication but unpractical when implemented in a big company where many users can become a bottleneck. Therefore we propose a lightweight Ciphertext Policy-Attribute Based Encryption (CP-ABE) algorithm to implement in IoT devices. CP-ABE algorithm is one-to-many technique suitable for secure grouping communication, but this algorithm is not a lightweight feature. Therefore this paper proposes a lightweight CP-ABE algorithm for IoT devices.

Scalable Access Control For Privacy-Aware Media Sharing

The prevalence of social networks has made it easier than ever for users to share their photos, videos, and other media content with anybody from anywhere. However, the easy access of user-generated media content also brings about privacy concerns. Traditional access control mechanisms, where a single access policy is made for a specific piece of content, cannot satisfy the user privacy requirements in large-scale media sharing systems. Instead, configuring multiple levels of access privileges for the shared media content is desired. On one hand, it conforms to the principle of social networks in information propagation. On the other hand, it accords with the diverse and complex social relationship among social network users. In this paper, we propose a scalable media access control (SMAC) system to enable such a configuration in a secure and efficient manner. The proposed SMAC system is empowered by the scalable ciphertext policy attribute-based encryption algorithm as well as a comprehensive key-management scheme. We provide formal security proof to prove the security of the proposed SMAC system. In addition, we conduct extensive experiments on mobile devices to demonstrate its efficiency.

Progressive Image Restoration Based on CP-ABE With Constant-Size Ciphertext and Constant Bilinear Calculation

Sharing photos on an open social platform with one-to-many features increases the leakage risk of information of the shared photos. Ciphertext-policy attribute-based encryption (CP-ABE) is a one-to-many public key cryptosystem, and its access policy can be set by data owners. Therefore, if we share the protected image on the social platform and encrypt the restoration parameters of the shared image with CP-ABE, then only the accessor whose attribute set satisfies the access policy of CP-ABE can decrypt the ciphertext corresponding to his/her attribute level and then restore the image with the corresponding sharpness level. Consequently, image information protection is realized in a one-to-many scenario. However, for the existing CP-ABE, only when further shortening its ciphertext, reducing the number of bilinear pairing calculations during decryption, and ensuring flexible access policies is it beneficial for CP-ABE to be widely used in popular smart terminals that can run social software. Furthermore, existing algorithms for restoring images also have room for improvement in terms of time and space requirements. For this reason, we propose a progressive image restoration strategy based on the improved CP-ABE in this paper. For the improvement of CP-ABE, we design a new encryption scheme to achieve a shorter constant-size ciphertext, construct an auxiliary function to help the independent authority centers generate private keys for users in new ways, design a decryption algorithm with only one bilinear pairing calculation, and provide the update algorithms for attribute revocation. Subsequently, we build a distributed CP-ABE based on our improved CP-ABE, and the correctness and security of the proposed CP-ABE algorithm are also proven. In addition, we follow the tree access policy to support the access policy, including AND, OR, NOT and threshold operations simultaneously, to adapt to the requirement of some user attributes that undergo frequent changes. Moreover, based on the atmospheric scattering model, we adopt three algorithms to restore the protected image in the dehazing mode according to the sharpness parameters. Compared with the existing literature, we provide users with not only a flexible and efficient access control strategy, shorter constant-size ciphertext and fewer bilinear calculations but also multiple algorithms for restoring images. The experimental results for six privilege levels demonstrate the superiority of our algorithms in protecting image information.

A lightweight secure conjunctive keyword search scheme in hybrid cloud

Keyword search over encrypted sensitive data is an essential technique in cloud computing. Many traditional secure retrieval schemes of the encrypted data mainly apply to single file-owner and single retrieval-party scenario, which cannot be used in cloud environment effectively. The emergence of Attribute-Based Encryption (ABE) provides a new solution to deliver secure and multi-parties keyword search over the encrypted data. However, most existing attribute-based keyword search schemes suffer problems, such as, imposed heavy computational burden for file-owner, limited expressive capability of access control policy, supported for single keyword search only, etc. Hence, we present a Lightweight secure Conjunctive Keyword Search scheme in hybrid cloud environment (LCKS) based on ciphertext-policy ABE algorithm, which supports file-owner authorized conjunctive keyword search for multi-parties. By delegating most computational tasks to private cloud servers, LCKS enables file-owners to generate keyword index efficiently while delivering a fine-grained access control policy through adopting an expressive tree structure. Both security analysis and performance evaluation show that LCKS is secure, highly efficient, and well suited for hybrid cloud.

Research on Access Control in Cloud Storage System: From Single to Multi-Clouds

Implementation of access control in cloud storage system is the essential method to protect users’ data from revealing sensitive information. The paper mainly investigates key technologies of access control in cloud storage system, including intra cloud and among multi-clouds. Firstly, we discuss about the focuses in recent researches and challenges of access control in cloud storage system. The access control researches here refer to cipher-text and cross-domain access control in cloud storage system. The key technologies introduce Ciphertext-Policy Attribute-Based Encryption algorithm(CP-ABE), ontology based attributes mapping, algebra based policies integration, solutions for identification, access authorization and identity federation. And the status of these fields is described next. At last, we concluded this paper and proposed some directions in the future work of access control research in cloud storage system. This paper can help to understand the key technologies of access control in cloud storage and helpful in the future researches.

A fine-grained and lightweight data access control scheme for WSN-integrated cloud computing

WSN-integrated cloud computing (WCC) has become a promising cloud service architecture, in which sensors and mobile devices are utilized as the data collecting and processing nodes for the cloud service model, while cloud servers can provide computing services and storage services with high performance and reliability. However, since cloud servers are not fully trusted, and sensors and mobile devices have very limited computing capability and storage capacity, WCC brings forth new challenges for data confidentiality, data integrity and access control when sensors store important data for sharing in the WCC environment. Moreover, there are still no proper solutions for fine-grained, efficient and secure data access control in WCC. To solve this issue, we propose a fine-grained and lightweight data access control scheme for WCC, namely FLAC, which includes a ciphertext-policy attribute-based encryption algorithm for data confidentiality and fine-grained data access control, and an attribute-based signature algorithm for data integrity and the many-read-many-write case of data access. By delegating most computation intensive tasks to cloud services, FLAC enables resource constrained sensors and mobile devices to perform security operations rapidly. The security assessment and performance evaluation demonstrate that FLAC is secure, highly efficient and well suited for WSN applications.

Towards efficient sharing of encrypted data in cloud-based mobile social network

Mobile social network is becoming more and more popular with respect to the development and popularity of mobile devices and interpersonal sociality. As the amount of social data increases in a great deal and cloud computing techniques become developed, the architecture of mobile social network is evolved into cloud-based that mobile clients send data to the cloud and make data accessible from clients. The data in the cloud should be stored in a secure fashion to protect user privacy and restrict data sharing defined by users. Ciphertext-policy attribute-based encryption (CP-ABE) is currently considered to be a promising security solution for cloud-based mobile social network to encrypt the sensitive data. However, its ciphertext size and decryption time grow linearly with the attribute numbers in the access structure. In order to reduce the computing overhead held by the mobile devices, in this paper we propose a new Outsourcing decryption and Match-then-decrypt CP-ABE algorithm (OM-CP-ABE) which firstly outsources the computation-intensive bilinear pairing operations to a proxy, and secondly performs the decryption test on the attributes set matching access policy in ciphertexts. The experimental performance assessments show the security strength and efficiency of the proposed solution in terms of computation, communication, and storage. Also, our construction is proven to be replayable choosen-ciphertext attacks (RCCA) secure based on the decisional bilinear Diffie-Hellman (DBDH) assumption in the standard model.