A Type-and-Identity-based Proxy Re-Encryption Scheme and its Application in Healthcare

Proxy re-encryption is a cryptographic primitive developed to delegate the decryption right from one party (the delegator) to another (the delegatee). In a proxy re-encryption scheme, the delegator assigns a key to a proxy to re-encrypt all messages encrypted with his public key such that the re-encrypted ciphertexts can be decrypted with the delegatee’s private key. We propose a type-and-identity-based proxy re-encryption scheme based on the Boneh-Franklin Identity Based Encryption (IBE) scheme. In our scheme, the delegator can categorize messages into different types and delegate the decryption right of each type to the delegatee through a proxy. Our scheme enables the delegator to provide the proxy fine-grained re-encryption capability. As an application, we propose a fine-grained Personal Health Record (PHR) disclosure scheme for healthcare service by applying the proposed scheme

Enhance Data Security Protection for Data Sharing in Cloud Storage System

Cloud computing technology can be used in all types of organizations. There are many benefits to use cloud storage. The most notable is data accessibility. Data stored in the cloud can be accessed at any time any place. Another advantage of cloud storage is data sharing between users. By sharing storage and networks with many users it is also possible for unauthorized users to access our data. To provide confidentiality of shared sensitive data, the cryptographic techniques are applied. So protect the data from unauthorized users, the cryptographic key is main challenge. In this method a data protection for cloud storage 1) The key is protected by two factors: Secret key is stored in the computer and personal security device 2) The key can be revoked efficiently by implementing proxy re-encryption and key separation techniques. 3) The data is protected in a fine grained way by adopting the attribute based encryption technique. So our proposed method provides confidentiality on data

Encrypted Shared Data Spaces

The deployment of Share Data Spaces in open, possibly hostile, environments arises the need of protecting the confidentiality of the data space content. Existing approaches focus on access control mechanisms that protect the data space from untrusted agents. The basic assumption is that the hosts (and their administrators) where the data space is deployed have to be trusted. Encryption schemes can be used to protect the data space content from malicious hosts. However, these schemes do not allow searching on encrypted data. In this paper we present a novel encryption scheme that allows tuple matching on completely encrypted tuples. Since the data space does not need to decrypt tuples to perform the search, tuple confidentiality can be guaranteed even when the data space is deployed on malicious hosts (or an adversary gains access to the host). Our scheme does not require authorised agents to share keys for inserting and retrieving tuples. Each authorised agent can encrypt, decrypt, and search encrypted tuples without having to know other agents’ keys. This is beneficial inasmuch as it simplifies the task of key management. An implementation of an encrypted data space based on this scheme is described and some preliminary performance results are given

Longitude : a privacy-preserving location sharing protocol for mobile applications

Location sharing services are becoming increasingly popular. Although many location sharing services allow users to set up privacy policies to control who can access their location, the use made by service providers remains a source of concern. Ideally, location sharing providers and middleware should not be able to access users’ location data without their consent. In this paper, we propose a new location sharing protocol called Longitude that eases privacy concerns by making it possible to share a user’s location data blindly and allowing the user to control who can access her location, when and to what degree of precision. The underlying cryptographic algorithms are designed for GPS-enabled mobile phones. We describe and evaluate our implementation for the Nexus One Android mobile phone

Re-Encryption Scheme for Providing Data Security in Clouds

Cloud computing is the trendy topic all over the world. With increase in popularity of cloud computing, more and more enterprises will outsource their sensitive data for sharing in a cloud. Cloud computing allows the users to share the data among the members of cloud. One of the issue in cloud computing is data security. Here the problem is whenever a user is revoked from cloud the data owners will send re-encryption command to cloud in order to re-encrypt the data so that the data is prevented from revoked users. In this paper, we propose a time-based re-encryption scheme using blowfish algorithm. This scheme allows the cloud to automatically re-encrypt the data based on the internal clock, users can access data within given time period, after time period get over user cannot access data, this scheme also prevents the revoked users from decrypting the data using their old decryption keys

Cloud Computing Algebra Homomorphic Encryption Scheme Based on Fermat's Little Theorem

© ASEE 2013Although cloud computing is growing rapidly, a key challenge is to build confidence that the cloud can handle data securely. Data is migrated to the cloud after encryption. However, this data must be decrypted before carrying out any calculations; which can be considered as a security breach. Homomorphic encryption solved this problem by allowing different operations to be conducted on encrypted data and the result will come out encrypted as well. In this paper, we propose the application of Algebraic Homomorphic Encryption Scheme based on Fermat's Little Theorem on cloud computing for better security