Study of security problem in cloud computing with access control based on the blockchain

Due to the lack of data security protection, a large number of malicious information leaks, which makes building information security (InfoSec) issues more and more attention. The construction information involves a large number of participants, and the number of construction project files is huge, leading to a huge amount of information. However, traditional network security information protection software is mostly passive, which is difficult to enhance its autonomy. Therefore, this text introduced data sharing algorithm in building InfoSec management. This text proposed an Attribute Based Encryption (ABE) algorithm based on data sharing, which is simple in calculation and strong in encrypting attributes. This algorithm was added to the building InfoSec management system (ISMS) designed in this text, which not only reduces the burden of relevant personnel, but also has flexible control and high security. The experimental results showed that when 10 users logged in to the system, the stability and security of the system designed in this text were 87% and 91% respectively. When 20 users logged in to the system, the system stability and security designed in this text were 89% and 92% respectively. When 80 users logged in to the system, the system stability and security designed in this text were 94% and 95% respectively. It can be found that the stability and security of the system have reached a high level, which can ensure the security of effective management of building information.

In this paper, we present two constructions of the attribute-based broadcast encryption(ABBE) algorithm. Attribute-based encryption(ABE) algorithm enables an access control mechanism over encrypted data by specifying access policies among private keys and ciphertexts. ABBE algorithm can be used to construct ABE algorithm with revocation mechanism. Revocation has a useful property that revocation can be done without affecting any non-revoked uers. The main difference between our algorithm and the classical ones derived from the complete subtree paradigm which is apt for military hierarchy. Our algorithm improve the efficiency from the previously best ABBE algorithm, in particular, our algorithm allows one to select or revoke users by sending ciphertext of constant size with respect to the number of attributes and by storing logarithm secret key size of the number of users. Therefore, our algorithm can be an option to applications where computation cost is a top priority and can be applied to military technologies in the near future.

A lightweight attribute-based encryption scheme for the Internet of Things

Fog computing as an extension of cloud computing is able to deploy data storage, computing and communication, control and management along the cloud to things continuum. From a systematic perspective, fog networks provide a distributed computing system with a hierarchical topology. Fog networks aim at meeting stringent latency requirements, reducing power consumption of end devices, providing real-time data processing and control with localized computing resources, and decreasing the burden of backhaul traffic to centralized data centers. However, in the era of fog computing and networks, we need to rethink about end-to-end network architecture, fog-enabled service management mechanisms, computing offloading and task allocation among fogcloud or fog-fog nodes, context-aware computing and communication tradeoff analysis, fogonomics and operational models, and scalability and security issues.

Media sharing in cloud environment, which supports sharing media content at any time and from anywhere, is a promising paradigm of social interaction. However, it also brings forth security issues in terms of data confidentiality and access control on media data consumers with different access privileges. One promising solution is scalable media access control, which is capable of providing data confidentiality by encrypting the media data and issuing the key to only authorized data consumers. More importantly, it can empower the data distributor to provide the same media content with various quality levels to the consumers with different privileges. Traditional schemes without utilizing the cloud resources achieve scalable media access control by generating access keys using hash chains. Despite of their computational efficiency, such schemes suffer from various problems including vulnerability to user collusion attack in two-dimensional case, inflexible key distribution, and ambiguous key revocation strategy. In this paper, we propose a novel two-dimensional-scalable access control by generating access keys based on Attribute-Based Encryption (ABE) algorithm. Moreover, the proposed scheme can efficiently achieve comprehensive key management including key distribution and key revocation by fully exploiting the cloud. Security analysis shows that the proposed scheme is able to provide collusion resistance, as well as forward and backward secrecy. We have also evaluated the efficiency of the scheme through numerical analysis and initial implementation.

Cloud computing becomes very popular and growing rapidly since the last few years, various information technology giants such as Amazon, Google, Microsoft and others speed up their growth in development of cloud computing systems and enhance services for consumers all over the world. Cloud computing provides virtual storage for the clients to avail storage, application, platform and services from their deployed servers over the internet. Various security issues such as; data insecure, data leakage, data availability, attacks; etc. could arise due to poor security policies. This paper discussed in detail security issues in terms of the CIA (Confidentiality, Integrity, and Availability) triangle from a service provider perspective over the services they provide to the end users. By these measurements high security can be achieve in cloud computing. Additionally, to protect confidential data from users on cloud the privacy actions are not updated accordingly. Severally, data backups on cloud cause high security risks. This survey paper analyzes the main security issues which are currently present in the cloud computing and offers best practices to service providers and enterprises hoping to control cloud service.

Three-dimensional medical volume data such as high-resolution map of medical CT, advanced optical images of scanners and MRI has increasingly developed to facilitate medicine diagnosis, the information storage, and the transmission, while it also brings security issues. In this paper, an encryption algorithm is presented, considering the s ecurity of three-dimensional medical volume data. Firstly, the position of the pixels of the medical volume data is scrambled by three-dimensional Arnold and a chaotic sequence is produced by Logistic map. S econdly, the image feature value is extracted as a key into the encryption process, and then a feedback mechanism was set up to change the pixel values. Finally, the definition of encryption performance indicators in the volume data is promoted. Through simulation, the algorithm has a large key space, which is highly sensitive to the initial value of keys. Furthermore, it can resist statistical, brute-force attack and differential attack effectively. The proposed encryption algorithm in this paper has high security and practical value, gi ving inspiration on security issues in the future with the large emergence of the three-dimensional volume data.

Attribute-based encryption mechanism is widely used in outsourcing systems because of its characteristics of 'one-to-many' communication. However, users' attributes often change dynamically. In order to solve the problem of attribute revocation in the attribute-based encryption scheme in the outsourcing systems, a revocable ciphertext policy attribute-based encryption in data outsourcing systems from lattices is proposed. The scheme uses the LWE problem to construct the encryption and decryption algorithm, which can resist the quantum attack. Tree-access structure is adopted to realise flexible fine-grained access strategy. In addition, with the help of the data outsourcing management server, the attribute key and ciphertext are updated to achieve immediate attribute revocation. The scheme is proved to be secure under the selective attribute and selective plaintext attacks. The comparative analysis shows that the scheme has a significant improvement in performance, and it supports immediate attribute revocation, which is more suitable for the dynamic change of users in the outsourcing systems, such as social network platforms.

Functional encryption (FE) which covers the notion of attribute-based encryption (ABE), is the cryptographic tool to realize fine-grained control on the accessibility of encrypted data. The traditional FE requires a central trusted authority to issue secret keys. It depends on the full-trust model, and is vulnerable to the security issue caused by key-escrow. While the registered FE (Reg-FE) achieves the zero-trust model and addresses the security issue by removing the use of central authority. It allows users to generate secret keys themselves and join the system by registering corresponding public keys to a curator. This work introduces delegated Reg-FE, which is a primitive with a new registration paradigm. It allows the registration of certain authorities that can issue secret keys for their respective classical FE sub-systems, beyond the prior work of registering plain users. Delegated Reg-FE implements a hybrid trust model within a two-level hierarchy. By redefining key escrow as a functional mechanism rather than a security concern, this model employs a zero-trust upper level which removes key-escrow, while the subsystem of each authority is locally full-trust and retains key-escrow mechanism. We construct four delegated Reg-FE schemes for functionalities that can be described as the $$2\times 2$$ combinations of linear function and policy check. Namely, Delegated Reg-IPFE, Delegated Reg-ABE, Reg-IPFE with delegated ABE, and Reg-ABE with delegated IPFE. All concrete schemes support bounded registrations and delegations, and achieve standard adaptive security under $$\textsc {MDDH}$$ assumption on prime-order bilinear group. Furthermore, these schemes only rely on black-box techniques. Technically, these schemes relies on dual-system techniques as prior registration-based works. And we devise a new “hierarchically invoked dual-system” technique on schemes which have sub-ABE delegation systems. Furthermore, we present a generic construction of Delegated Reg-FE from the combination of Reg-FE and FE. The instantiations of this generic construction demonstrate the feasibility of delegated Reg-FE, supporting arbitrary functions as well as unbounded numbers of registrations and delegations. However, this approach requires non-black-box techniques and achieves weaker semi-adaptive security without malicious registration, where the semi-adaptive means the adversary claims the challenge after seeing common reference string but before making any query. Its security relies solely on the underlying assumptions of the Reg-FE and FE components.

In distributed systems users need to share sensitive objects with others based on the recipients' ability to satisfy a policy. Attribute-Based Encryption (ABE) is a new paradigm where such policies are specified and cryptographically enforced in the encryption algorithm itself. Ciphertext-Policy ABE (CP-ABE) is a form of ABE where policies are associated with encrypted data and attributes are associated with keys. In this work we focus on improving the flexibility of representing user attributes in keys. Specifically, we propose Ciphertext Policy Attribute Set Based Encryption (CP-ASBE) - a new form of CP-ABE - which, unlike existing CP-ABE schemes that represent user attributes as a monolithic set in keys, organizes user attributes into a recursive set based structure and allows users to impose dynamic constraints on how those attributes may be combined to satisfy a policy. We show that the proposed scheme is more versatile and supports many practical scenarios more naturally and efficiently. We provide a prototype implementation of our scheme and evaluate its performance overhead.

PPNNP: A privacy-preserving neural network prediction with separated data providers using multi-client inner-product encryption

Key revocation is one of the most challenging and open issues in attribute-based encryption (ABE). The previous revocable ABE schemes feature a mechanism that revokes the attribute key periodically without any consideration of the user membership associated with the attribute. Thus, non-revoked users are enforced to access the key authority periodically to receive keying materials in order to update the current key. This is due to the fact that the revocation is done only on the attribute level, which results in security and scalability problems. In this paper, we propose a fine-grained user revocation scheme without affecting any non-revoked users who share the same attributes in ciphertext-policy ABE; it does not require the users to access the key authority and to update keys periodically. The proposed scheme improves the efficiency compared with previous revocable schemes and enhances the security in terms of the backward/forward secrecy on any membership changes in the ciphertext-policy ABE system. Copyright © 2011 John Wiley & Sons, Ltd.

Hybrid power systems are rapidly becoming a standard for all smart grids as we gear towards cleaner alternative energy sources. However their management is quite complex due to the different power generating sources which leads to complex management due to the multitudes of data exchange involved. Despite its attractive features, Hybrid Smart Grids remain vulnerable to security threats. In this paper, we summarize some of these potential security issues by exploring data access control mechanisms that ensure privacy to customers. We hereby propose a security model based on attribute-based encryption (ABE). The entire grid network is subdivided into clusters each with its own remote terminal unit (RTU) as well as a gateway smart meter. User data in a given cluster is aggregated and sent to the local substation where it is monitored by the RTU. RTUs and users have attributes and cryptographic keys distributed by several key distribution centers (KDC). RTUs send data encrypted under a set of attributes. Users can decrypt information provided they have valid attributes. The access control scheme is quite resilient because of its being distributed in nature and does not rely on a single KDC to distribute keys. The encryption algorithm is based on Diffie-Hellman key establishment protocol and hash-based message authentication code, which allows smart meters at different clusters of the smart grid to mutually authenticate prior to data/information exchange and in the process maintaining low latency as well as relatively fewer authentication associated messages. Overall the control scheme is relatively collusion resistant.

Data privacy is now-a-days a special issue in era of Internet of Things because of the big data stored and transmitted by the public/private devices. Different types and levels of privacy can be provided at different layers of IoT architecture, also different mechanisms operate at different layers of IoT architecture. This article presents the work being done towards the design of a generic framework to integrate these privacy preserving mechanisms at different layers of IoT architecture and can ensure privacy preservation in a heterogeneous IoT environment. The data is classified into different levels of secrecy and appropriate rules and mechanisms are applied to ensure this privacy. The proposed framework is implemented and evaluated for its performance with security and execution time or primary parameters. Various scenarios are also evaluated, and a comparison is done with an existing mechanism ABE (Attribute Based Encryption). It has been found that the proposed work takes less time and is more secure due to short key length and randomness of the parameters used in encryption algorithm.

Securing and issuing academic transcripts is one of the most mind-numbing tasks in the modern world as there are multiple disciplines and manually maintaining the accuracy of the data is tough. Moreover, the data is stored in an untrusted centralized cloud storage system, this type of model possesses a number of issues like high operational cost, data availability, and data security. The current research paper tries to exploit the decentralization and the smart contract feature of the ethereum blockchain. A model where basic student data is stored in a smart contract and large files are stored in IPFS protocol.