Ciphertext-policy attribute-based encryption (CP-ABE) is an access control mechanism where a data provider encrypts a secret message and then sends the ciphertext to the receivers according to the access policy which she/he decides. If the attributes of the receivers match the access policy, then they can decrypt the ciphertext. This manuscript shows a relation between ABE and identity-based en...

As an extension of identity-based encryption scheme, attribute-based encryption scheme also has the key escrow problem. Multi-authority attribute-based encryption schemes are principal solution, but it is at the cost of the introducing extra infrastructure and communication. This paper introduces the concept of attribute-based certificatless encryption system (ABCE), which is a new approach to ...

In this work, we present HIBE and ABE schemes which are “unbounded” in the sense that the public parameters do not impose additional limitations on the functionality of the systems. In all previous constructions of HIBE in the standard model, a maximum hierarchy depth had to be fixed at setup. In all previous constructions of ABE in the standard model, either a small universe size or a bound on...

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In this paper, we propose the notion of Verifiable Attribute-Based Encryption (VABE) and give two constructs of key-policy VABE. One is with a single authority, and the other is with multi authorities. Not only our schemes are proved secure as the previous ABE schemes, they also provide a verification property. This could not be trivially solved, such as trying random decryption. Adding the ver...

Ciphertext-Policy Attribute-Based Encryption (CP-ABE) allows to encrypt data under an access policy, specified as a logical combination of attributes. Such ciphertexts can be decrypted by anyone with a set of attributes that fits the policy. In this paper, we introduce the concept of Distributed Attribute-Based Encryption (DABE), where an arbitrary number of parties can be present to maintain a...

We propose a Multi-Authority Attribute-Based Encryption (ABE) system. In our sys-tem, any party can become an authority and there is no requirement for any global coor-dination other than the creation of an initial set of common reference parameters. A partycan simply act as an ABE authority by creating a public key and issuing private keys todifferent users that reflect their a...

The field of data management has been reformed by the Cloud computing technologies which offered valuable establishments and amended storage restrictions barriers for its users. In large enterprises cloud extensively used implementation due to benefits. There are still lot security threats in cloud. owners suffer from privacy issues considered as one major concerns. Data can be secured employin...

We propose a Multi-Authority Attribute-Based Encryption (ABE) system. In our sys-tem, any party can become an authority and there is no requirement for any global coor-dination other than the creation of an initial set of common reference parameters. A partycan simply act as an ABE authority by creating a public key and issuing private keys todifferent users that reflect their a...