A Multi-User Public Key Encryption with Multi-Keyword Search out of Bilinear Pairings

Internet of Things (IoT) and cloud computing are adopted widely in daily life and industrial production. Sensors of IoT equipment gather personal, sensitive and important data, which is stored in a cloud server. The cloud helps users to save cost and collaborate. However, the privacy of data is also at risk. Public-key encryption with keyword search (PEKS) is convenient for users to use the data without leaking privacy. In this article, we give a scheme of PEKS for a multi-user to realize the multi-keyword search at once and extend it to show a rank based on keywords match. The receiver can finish the search by himself or herself. With private cloud and server cloud, most users’ computing can be outsourced. Moreover, the PEKS can be transferred to a multi-user model in which the private cloud is used to manage receivers and outsource. The store cloud and the private cloud both obtain nothing with the keyword information. Then our IoT devices can easily run these protocols. As we do not use any pairing operations, the scheme is under more general assumptions that means the devices do not need to take on the heavy task of calculating pairing.

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Public Key Encryption with Keyword Search from Lattices in Multiuser Environments

Mathematical Problems in Engineering ◽

10.1155/2016/6549570 ◽

2016 ◽

Vol 2016 ◽

pp. 1-7 ◽

Cited By ~ 1

Author(s):

Daini Wu ◽

Xiaoming Wang ◽

Qingqing Gan

Keyword(s):

Data Privacy ◽

Keyword Search ◽

Random Oracle Model ◽

Random Oracle ◽

Public Key ◽

Public Key Encryption ◽

Encrypted Data ◽

Cloud Server ◽

Learning With Errors ◽

Multiuser Environments

A public key encryption scheme with keyword search capabilities is proposed using lattices for applications in multiuser environments. The proposed scheme enables a cloud server to check if any given encrypted data contains certain keywords specified by multiple users, but the server would not have knowledge of the keywords specified by the users or the contents of the encrypted data, which provides data privacy as well as privacy for user queries in multiuser environments. It can be proven secure under the standard learning with errors assumption in the random oracle model.

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ISEkFT

Journal of Information Technology Research ◽

10.4018/jitr.2019070108 ◽

2019 ◽

Vol 12 (3) ◽

pp. 133-153 ◽

Cited By ~ 1

Author(s):

Mamta ◽

Brij B. Gupta ◽

Syed Taqi Ali

Keyword(s):

Keyword Search ◽

Public Key ◽

Public Key Encryption ◽

The Public ◽

Fuzzy Search ◽

Cloud Server ◽

Fuzzy Keyword Search ◽

Identity Based ◽

Guessing Attack ◽

Overall Reliability

Public-key encryption with keyword search (PEKS) is a well-known technique which allows searching on encrypted data using the public key system. However, this technique suffers from the keyword guessing attack (KGA). To address this problem, a modified version of PEKS called public key encryption with fuzzy keyword search (PEFKS) has been introduced where each keyword is associated with an exact search trapdoor (EST) and a fuzzy search trapdoor (FST) which is provided to the cloud server. PEFKS prevents KGA in such a way that two or maximum three keywords share the same FST. Hence, even if the cloud server knows the FST it cannot link it to the corresponding keyword. But, with a probability of 1/3 the malicious cloud server can still guess the keyword corresponding to FST. Therefore, in this article, the authors present an approach which can improve the security of the PEFKS technique by reducing the probability of guessing the keyword to 1/k where k is the number of keywords that share the same FST, thus enhancing the overall reliability. In addition, the authors have used an identity-based encryption (IBE) as an underlying technique to construct the searchable encryption scheme and proved its security in the standard model.

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PUBLIC KEY ENCRYPTION WITH CONJUNCTIVE FIELD FREE KEYWORD SEARCH SCHEME

INTERNATIONAL JOURNAL OF COMPUTERS & TECHNOLOGY ◽

10.24297/ijct.v15i14.834 ◽

2016 ◽

Vol 15 (14) ◽

pp. 7423-7434

Author(s):

FAIROUZ SHER ALI ◽

SONG FENG LU

Keyword(s):

Keyword Search ◽

Bilinear Pairings ◽

Public Key ◽

Public Key Encryption ◽

Sensitive Data ◽

Remote Server ◽

New Public ◽

Searchable Symmetric Encryption ◽

Encryption Schemes ◽

Keyword Searches

Searchable encryption allows a remote server to search over encrypted documents without knowing the sensitive data contents. Prior searchable symmetric encryption schemes focus on single keyword search. Conjunctive Keyword Searches (CKS) schemes improve system usability by retrieving the matched documents. In this type of search, the user has to repeatedly perform the search protocol for many times. Most of existent (CKS) schemes use conjunctive keyword searches with fixed position keyword fields, this type of search is not useful for many applications, such as unstructured text. In our paper, we propose a new public key encryption scheme based on bilinear pairings, the scheme supports conjunctive keyword search queries on encrypted data without needing to specify the positions of the keywords where the keywords can be in any arbitrary order. Instead of giving the server one trapdoor for each keyword in the conjunction set, we use a bilinear map per a set of combined keywords to make them regarded as one keyword. In another meaning, the proposed method will retrieve the data in one round of communication between the user and server. Furthermore, the search process could not reveal any information about the number of keywords in the query expression. Through analysis section we determine how such scheme could be used to guarantee fast and secure access to the database.

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