PROXY RE-ENCRYPTION SCHEMES FOR SECURE CLOUD DATA AND APPLICATIONS: A SURVEY

This paper shows an overview on Proxy re-encryption procedures concerning secure cloud information and its application. To keep delicate client information secret against untrusted servers, crypto-realistic strategies are utilized to give security and access control in mists. As the information is shared over the system, it is should have been encoded. There are numerous encryption conspires that give security and access control over the network.Proxy re-encryption empowers the semi-confided in intermediary server to re-scramble the figure content encoded under Alice's open key to another ciphertext en-crypted under Bob's open key. The re-encryption is finished without the server having the capacity to decode the ciphertext.Cloud administrations and applications ought to take after the standard safety efforts in-cluding information secrecy, integrity,privacy, power and access control.In this paper the intermediary re-encryption(PRE) plans, Con-ditional PRE,Identity based PRE and Broadcast PRE,Type based PRE, Key private PRE,Attribute based PRE,Threshold PRE and its part in anchoring the cloud information are clarified

Privacy-Preserving Quick Authentication in Fast Roaming Networks

Vehicular networks will become an important component for information accesses in one’s daily life. A vehicular net-work provides a vehicular user not only chances to communi-cate with peer vehicles but also to use Internet through road-side access points (APs). During a trip a vehicular user could roam across multiple APs either belong to their home wireless domain or to domains owned by different authorities. This poses challenges on privacy and network performance to the current public wireless network access protocols. In this pa-per we explore an idea that shifts the paradigm of authen-tication that goes back to home networks to a paradigm of authentication that performs at the APs. We propose three authentication schemes in realizing the idea. These schemes are designed for preserving user’s identity and location pri-vacy. They also greatly reduce response time for authentica-tion when roaming. The paper then analyzes the security and privacy properties of these schemes as well as the efficiency of them.

The Trusted Server: A secure computational environment for privacy compliant evaluations on plain personal data

A growing framework of legal and ethical requirements limit scientific and commercial evaluation of personal data. Typically, pseudonymization, encryption, or methods of distributed computing try to protect individual privacy. However, computational infrastructures still depend on human system administrators. This introduces severe security risks and has strong impact on privacy: system administrators have unlimited access to the computers that they manage including encryption keys and pseudonymization-tables. Distributed computing and data obfuscation technologies reduce but do not eliminate the risk of privacy leakage by administrators. They produce higher implementation effort and possible data quality degradation. This paper proposes the Trusted Server as an alternative approach that provides a sealed and inaccessible computational environment in a cryptographically strict sense. During operation or by direct physical access to storage media, data stored and processed inside the Trusted Server can by no means be read, manipulated or leaked, other than by brute-force. Thus, secure and privacy-compliant data processing or evaluation of plain person-related data becomes possible even from multiple sources, which want their data kept mutually secret

Secure multi party computations for electronic voting

Στην παρούσα εργασία, μελετούμε το πρόβλημα της ηλεκτρονικής ψηφοφορίας. Θεωρούμε ότι είναι έκφανση μιας γενικής διαδικασίας αποφάσεων που μπορεί να υλοποιηθεί μέσω υπολογισμών πολλαπλών οντοτήτων, οι οποίοι πρέπει να ικανοποιούν πολλές και αντικρουόμενες απαιτήσεις ασφαλείας. Έτσι μελετούμε σχετικές προσεγγίσεις οι οποίες βασιζονται σε κρυπτογραφικές τεχνικές, όπως τα ομομορφικά κρυπτοσυστήματα, τα δίκτυα μίξης και οι τυφλές υπογραφές. Αναλύουμε πώς προσφέρουν ακεραιότητα και ιδιωτικότητα (μυστικότητα) στην διαδικασία και την σχέση τους με την αποδοτικότητα. Εξετάζουμε τα είδη λειτουργιών κοινωνικής επιλογής που μπορούν να υποστηρίξουν και παρέχουμε δύο υλοποιήσεις. Επιπλέον ασχολούμαστε με την αντιμετώπιση ισχυρότερων αντιπάλων μη παρέχοντας αποδείξεις ψήφου ή προσφέροντας δυνατότητες αντίστασης στον εξαναγκασμό. Με βάση την τελευταία έννοια προτείνουμε μια τροποποίηση σε ένα ευρέως χρησιμοποιούμενο πρωτόκολλο. Τέλος μελετούμε δύο γνωστές υλοποιήσεις συστημάτων ηλεκτρονικής ψηφοφοριας το Helios και το Pret a Voter .In this thesis, we study the problem of electronic voting as a general decision making process that can be implemented using multi party computations, fulfilling strict and often conflicting security requirements. To this end, we review relevant cryptographic techniques and their combinations to form voting protocols. More specifically, we analyze schemes based on homomorphic cryptosystems, mixnets with proofs of shuffles and blind signatures. We analyze how they achieve integrity and privacy in the voting process, while keeping efficiency. We examine the types of social choice functions that can be supported by each protocol. We provide two proof of concept implementations. Moreover, we review ways to thwart stronger adversaries by adding receipt freeness and coercion resistance to voting systems. We build on the latter concept to propose a modification to a well known protocol. Finally, we study two actual e-Voting implementations namely Helios and Pret a Voter

Matters of Coercion-Resistance in Cryptographic Voting Schemes

This work addresses coercion-resistance in cryptographic voting schemes. It focuses on three particularly challenging cases: write-in candidates, internet elections and delegated voting. Furthermore, this work presents a taxonomy for analyzing and comparing a huge variety of voting schemes, and presents practical experiences with the voting scheme Bingo Voting

Advances in cryptographic voting systems

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2006.Includes bibliographical references (p. 241-254).Democracy depends on the proper administration of popular elections. Voters should receive assurance that their intent was correctly captured and that all eligible votes were correctly tallied. The election system as a whole should ensure that voter coercion is unlikely, even when voters are willing to be influenced. These conflicting requirements present a significant challenge: how can voters receive enough assurance to trust the election result, but not so much that they can prove to a potential coercer how they voted? This dissertation explores cryptographic techniques for implementing verifiable, secret-ballot elections. We present the power of cryptographic voting, in particular its ability to successfully achieve both verifiability and ballot secrecy, a combination that cannot be achieved by other means. We review a large portion of the literature on cryptographic voting. We propose three novel technical ideas: 1. a simple and inexpensive paper-base cryptographic voting system with some interesting advantages over existing techniques, 2. a theoretical model of incoercibility for human voters with their inherent limited computational ability, and a new ballot casting system that fits the new definition, and 3. a new theoretical construct for shuffling encrypted votes in full view of public observers.by Ben Adida.Ph.D

Unleashing The Potential of Data Ecosystems: Establishing Digital Trust through Trust-Enhancing Technologies

Companies increasingly innovate data-driven business models, enabling them to create new products and services. Emerging data ecosystems provide these companies access to complementary data, offering them additional potential. This, however remains untapped, as a lack of digital trust prevents companies from sharing data within these ecosystems. By using trust-enhancing technologies, companies can establish trust; this can be explained through the theoretical lens of system trust. Using a design research approach helped us to unlock the knowledge of 21 experts and identify five technologies with the potential to solve the trust challenge: self-sovereign identities, differential privacy, fully homomorphic encryption, trusted execution environments and secure multiparty computation. We integrated these technologies into the data sharing process in data ecosystems and elaborated on their limitations and maturity. Ultimately, we derived two principles that allow for adapting our results to future technological developments: complementarity and customization

Data storage security and privacy in cloud computing: A comprehensive survey

Cloud Computing is a form of distributed computing wherein resources and application platforms are distributed over the Internet through on demand and pay on utilization basis. Data Storage is main feature that cloud data centres are provided to the companies/organizations to preserve huge data. But still few organizations are not ready to use cloud technology due to lack of security. This paper describes the different techniques along with few security challenges, advantages and also disadvantages. It also provides the analysis of data security issues and privacy protection affairs related to cloud computing by preventing data access from unauthorized users, managing sensitive data, providing accuracy and consistency of data store

Secure data sharing in cloud computing: a comprehensive review

Cloud Computing is an emerging technology, which relies on sharing computing resources. Sharing of data in the group is not secure as the cloud provider cannot be trusted. The fundamental difficulties in distributed computing of cloud suppliers is Data Security, Sharing, Resource scheduling and Energy consumption. Key-Aggregate cryptosystem used to secure private/public data in the cloud. This key is consistent size aggregate for adaptable decisions of ciphertext in cloud storage. Virtual Machines (VMs) provisioning is effectively empowered the cloud suppliers to effectively use their accessible resources and get higher benefits. The most effective method to share information resources among the individuals from the group in distributed storage is secure, flexible and efficient. Any data stored in different cloud data centers are corrupted, recovery using regenerative coding. Security is provided many techniques like Forward security, backward security, Key-Aggregate cryptosystem, Encryption and Re-encryption etc. The energy is reduced using Energy-Efficient Virtual Machines Scheduling in Multi-Tenant Data Centers

Secure Data Sharing in Cloud Computing: A Comprehensive Review

Cloud Computing is an emerging technology, which relies on sharing computing resources. Sharing of data in the group is not secure as the cloud provider cannot be trusted. The fundamental difficulties in distributed computing of cloud suppliers is Data Security, Sharing, Resource scheduling and Energy consumption. Key-Aggregate cryptosystem used to secure private/public data in the cloud. This key is consistent size aggregate for adaptable decisions of ciphertext in cloud storage. Virtual Machines (VMs) provisioning is effectively empowered the cloud suppliers to effectively use their accessible resources and get higher benefits. The most effective method to share information resources among the individuals from the group in distributed storage is secure, flexible and efficient. Any data stored in different cloud data centers are corrupted, recovery using regenerative coding. Security is provided many techniques like Forward security, backward security, Key-Aggregate cryptosystem, Encryption and Re-encryption etc. The energy is reduced using Energy-Efficient Virtual Machines Scheduling in Multi-Tenant Data Centers