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Securing Cloud Data
Published in Olivier Terzo, Lorenzo Mossucca, Cloud Computing with e-Science Applications, 2017
Initially, for DACC the parameters of the scheme and the size of the group are decided. The size of the group is chosen to be high, for example, 232 + 1. AA Aj selects the set of attributes Lj. An owner Uu who wants to store information in the cloud chooses a set of attributes Iu that are specific to the data it wants to encrypt. These attributes may belong to different KDCs. It then decides on the access structure and converts the access tree to a linear secret sharing scheme (LSSS) matrix R using the algorithm given in Reference 31. Depending on the attributes it possesses and the keys it receives from the KDC, it encrypts and sends the data and the access matrix. Each user is given a set of attributes when the user registers for services from owners. The attributes are not given by the cloud but by the KDCs. An ssh protocol (secure shell protocol [1]) is used to securely transfer the attribute information. KDCs give secret keys to users. When a user wants to access some information, the user asks the cloud for the data record. The cloud gives an encrypted copy of the data. If a user has a valid set of attributes, then the user calculates the data using the secret key that it possesses.
Key Establishment Protocols
Published in Alfred J. Menezes, Paul C. van Oorschot, Scott A. Vanstone, Handbook of Applied Cryptography, 2018
Alfred J. Menezes, Paul C. van Oorschot, Scott A. Vanstone
Threshold schemes are a special class of generalized secret sharing schemes, in which the access structure consists of precisely all t-subsets of users. An access structure is called monotone if, whenever a particular subset A of users is an authorized subset, then any subset of P containing A is also authorized. Monotone access structures are a requirement in many applications, and most natural schemes are monotone. Perfect secret sharing schemes have a monotone access structure as a consequence of the entropy formulation in Definition 12.73.
Need for Lightweight Attribute-Based Encryption (ABE) for Cloud-Based IoT
Published in Amit Kumar Tyagi, Niladhuri Sreenath, Handbook of Research of Internet of Things and Cyber-Physical Systems, 2022
Keerti Naregal, Vijay H. Kalmani
CPABE is found to be more suitable compared to KPABE for access control as it provides the owner of the message or file the rights to decide who gets the access by defining the access structure [15]. When any system uses ABE there are going to be frequent bilinear pairing operations, and it is found that bilinear pairing is more costly and complex compared to other operations like multiplication or exponentiation. In the near future we can see research developments in this field and solutions providing a lightweight encryption technique for Cloud Based IoT.
Hybrid lightweight cryptography with attribute-based encryption standard for secure and scalable IoT system
Published in Connection Science, 2022
Mounika Jammula, Venkata Mani Vakamulla, Sai Krishna Kondoju
An LWC is a technique by which any information or message is exchanged securely between two or more remote parties through a communication network under the surveillance of an eavesdropper. Every cryptographic scheme consists of two processes, namely encryption and decryption. In the encryption process, a text message is encrypted (encoded) into a cipher text message, while during the decryption process, the encoded cipher text message is again decrypted (decoded) into the original text message. Moreover, every cryptographic scheme is either based on a pair of keys (public and private) or a single (shared) key which is/are used to convert the text message into cipher text and vice-versa. The proposed LWC-ABE method supports high expressiveness, access policy updates, large attribute domains, and white box traceability properties. White-box traceability is the process by which the system may identify the malicious user if a user in the system intentionally leaks their decryption key to an unauthorised user using the information included in the key. The features of the proposed LWC-ABE method are illustrated as follows: Large attribute domain: the number of authorised institutions influences the size of public parameters, which does not rise in a linear manner with respect to attributes. There is no need to update the system attributes if the system is formed.Policy modification: The data owners continuously change the policy access specifications and generate the different ciphertexts to meet the higher security standards. Further, according to policy modification, the data owners also fine tune the data access properties in a flexible manner.The system has the potential capability to monitor malevolent users who unlawfully distribute private keys. The white box traceability creates a list of users with their access permissions, which helps to identify unauthorised users with low computational cost.Many authorised authorities: The data integrity problems are solved by introducing the multiple authority system, which also solves the issue of the single authority's insufficient credibility. Human inaccuracy, whether intentionally or inadvertent, may undermine data integrity. Transfer errors, such as unintentional alterations or data compromise when moving information between devices. vulnerabilities, malware/viruses, hacking, and other online dangers are the main causes of data integrity.It allows for any monotonous access structure and any customisable access control access approach.