A comprehensive meta-analysis of cryptographic security mechanisms for cloud computing

The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.The concept of cloud computing offers measurable computational or information resources as a service over the Internet. The major motivation behind the cloud setup is economic benefits, because it assures the reduction in expenditure for operational and infrastructural purposes. To transform it into a reality there are some impediments and hurdles which are required to be tackled, most profound of which are security, privacy and reliability issues. As the user data is revealed to the cloud, it departs the protection-sphere of the data owner. However, this brings partly new security and privacy concerns. This work focuses on these issues related to various cloud services and deployment models by spotlighting their major challenges. While the classical cryptography is an ancient discipline, modern cryptography, which has been mostly developed in the last few decades, is the subject of study which needs to be implemented so as to ensure strong security and privacy mechanisms in today’s real-world scenarios. The technological solutions, short and long term research goals of the cloud security will be described and addressed using various classical cryptographic mechanisms as well as modern ones. This work explores the new directions in cloud computing security, while highlighting the correct selection of these fundamental technologies from cryptographic point of view

Secure Batch Deduplication Without Dual Servers in Backup System

Cloud storage provides highly available and low cost resources to users. However, as massive amounts of outsourced data grow rapidly, an effective data deduplication scheme is necessary. This is a hot and challenging field, in which there are quite a few researches. However, most of previous works require dual-server fashion to be against brute-force attacks and do not support batch checking. It is not practicable for the massive data stored in the cloud. In this paper, we present a secure batch deduplication scheme for backup system. Besides, our scheme resists the brute-force attacks without the aid of other servers. The core idea of the batch deduplication is to separate users into different groups by using short hashes. Within each group, we leverage group key agreement and symmetric encryption to achieve secure batch checking and semantically secure storage. We also extensively evaluate its performance and overhead based on different datasets. We show that our scheme saves the data storage by up to 89.84%. These results show that our scheme is efficient and scalable for cloud backup system and can also ensure data confidentiality

Secure Cloud Storage with Client-Side Encryption Using a Trusted Execution Environment

With the evolution of computer systems, the amount of sensitive data to be stored as well as the number of threats on these data grow up, making the data confidentiality increasingly important to computer users. Currently, with devices always connected to the Internet, the use of cloud data storage services has become practical and common, allowing quick access to such data wherever the user is. Such practicality brings with it a concern, precisely the confidentiality of the data which is delivered to third parties for storage. In the home environment, disk encryption tools have gained special attention from users, being used on personal computers and also having native options in some smartphone operating systems. The present work uses the data sealing, feature provided by the Intel Software Guard Extensions (Intel SGX) technology, for file encryption. A virtual file system is created in which applications can store their data, keeping the security guarantees provided by the Intel SGX technology, before send the data to a storage provider. This way, even if the storage provider is compromised, the data are safe. To validate the proposal, the Cryptomator software, which is a free client-side encryption tool for cloud files, was integrated with an Intel SGX application (enclave) for data sealing. The results demonstrate that the solution is feasible, in terms of performance and security, and can be expanded and refined for practical use and integration with cloud synchronization services

Um estudo sobre a segurança e privacidade no armazenamento de dados em nuvens

Orientador: Marco Aurélio Amaral HenriquesDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de ComputaçãoResumo: Armazenamento de dados na nuvem é um serviço que traz diversas vantagens aos seus usuários. Contudo, em sistemas de nuvens públicas, os riscos envolvidos na terceirização do armazenamento de dados pode ser uma barreira para a adoção deste serviço por aqueles preocupados com sua privacidade. Vários provedores de serviços em nuvem que afirmam proteger os dados do usuário não atendem alguns requisitos considerados essenciais em um serviço seguro, confiável e de fácil utilização, levantando questionamentos sobre a segurança efetivamente obtida. Apresentamos neste trabalho um estudo relacionado aos requisitos de privacidade dos usuários e de segurança de seus dados em nuvens públicas. O estudo apresenta algumas técnicas normalmente usadas para atender tais requisitos, juntamente com uma análise de seus benefícios e custos relativos. Além disso, ele faz uma avaliação destes requisitos em vários sistemas de nuvens públicas. Depois de comparar estes sistemas, propomos um conjunto de requisitos e apresentamos, como prova de conceito, uma aplicação baseada nos mesmos, a qual melhora a segurança dos dados e a privacidade dos usuários. Nós mostramos que é possível proteger os dados armazenados nas nuvens contra o acesso por terceiros (incluindo os administradores das nuvens) sem sobrecarregar o usuário com protocolos ou procedimentos complexos de segurança, tornando o serviço de armazenamento em nuvens uma escolha mais confiável para usuários preocupados com sua privacidadeAbstract: Cloud data storage is a service that brings several advantages for its users. However, in public cloud systems, the risks involved in the outsourcing of data storage can be a barrier to the adoption of this service by those concerned with privacy. Several cloud service providers that claim to protect user's data do not fulfill some requirements considered essential in a secure, reliable and easy to use service, raising questions about the effective security obtained. We present here a study related to user's privacy and data security requirements on public clouds. The study presents some techniques normally used to fulfill those requirements, along with an analysis of their relative costs and benefits. Moreover, it makes an evaluation of them in several public cloud systems. After comparing those systems, we propose a set of requirements and present a proof of concept application based on them, which improves data security and user privacy in public clouds. We show that it is possible to protect cloud stored data against third party (including cloud administrators) access without burdening the user with complex security protocols or procedures, making the public cloud storage service a more reliable choice to privacy concerned usersMestradoEngenharia de ComputaçãoMestre em Engenharia Elétrica153392/2014-2CNP

Survey on Secure Authorized De-duplication in Hybrid

Nowadays, cloud computing provides high amount of storage space and massive parallel computing at effective cost. As cloud computing becomes prevalent, excessive amount of data being stored in the cloud. However, exponential growth of ever-increasing volume of data has raised many new challenges. De-duplication technique is specialized data compression technique which eliminates redundant data as well as improves storage and bandwidth utilization. Convergent encryption technique is proposed to enforce confidentiality during de-duplication, which encrypt data before outsourcing. To better protect data security, we present different privileges of user to address problem of authorized data de-duplication. We also present several new de-duplication constructions supporting authorized duplicate check in hybrid cloud architecture, which incurs minimal overhead compared to normal operation