On the Knowledge Soundness of a Cooperative Provable Data Possession Scheme in Multicloud Storage

On the Knowledge Soundness of a Cooperative Provable Data Possession Scheme in Multicloud Storage Provable data possession (PDP) is a probabilistic proof technique for cloud service providers (CSPs) to prove the clients’ data integrity without downloading the whole data. In 2012, Zhu et al. proposed the construction of an efficient PDP scheme for multicloud storage. They studied the existence of multiple CSPs to cooperatively store and maintain the clients’ data. Then, based on homomorphic verifiable response and hash index hierarchy, they presented a cooperative PDP (CPDP) scheme from the bilinear…

Read More

Key-Aggregate Cryptosystem for Scalable Data Sharing in Cloud Storage

Key-Aggregate Cryptosystem for Scalable Data Sharing in Cloud Storage Data sharing is an important functionality in cloud storage. In this paper, we show how to securely, efficiently, and flexibly share data with others in cloud storage. We describe new public-key cryptosystems that produce constant-size ciphertexts such that efficient delegation of decryption rights for any set of ciphertexts are possible. The novelty is that one can aggregate any set of secret keys and make them as compact as a single key, but encompassing the power of all the keys being aggregated.…

Read More

Oruta: Privacy-Preserving Public Auditing for Shared Data in the Cloud

Oruta: Privacy-Preserving Public Auditing for Shared Data in the Cloud   With cloud data services, it is commonplace for data to be not only stored in the cloud, but also shared across multiple users. Unfortunately, the integrity of cloud data is subject to skepticism due to the existence of hardware/software failures and human errors. Several mechanisms have been designed to allow both data owners and public verifiers to efficiently audit cloud data integrity without retrieving the entire data from the cloud server. However, public auditing on the integrity of shared…

Read More

Hierarchical Prediction and Context Adaptive Coding for Lossless Color Image Compression

Hierarchical Prediction and Context Adaptive Coding for Lossless Color Image Compression This paper presents a new lossless color image compression algorithm, based on the hierarchical prediction and context-adaptive arithmetic coding. For the lossless compression of an RGB image, it is first decorrelated by a reversible color transform and then Y component is encoded by a conventional lossless grayscale image compression method. For encoding the chrominance images, we develop a hierarchical scheme that enables the use of upper, left, and lower pixels for the pixel prediction, whereas the conventional raster scan…

Read More

Approximate Shortest Distance Computing: A Query-Dependent Local Landmark Scheme

Approximate Shortest Distance Computing: A Query-Dependent Local Landmark Scheme Shortest distance query is a fundamental operation in large-scale networks. Many existing methods in the literature take a landmark embedding approach, which selects a set of graph nodes as landmarks and computes the shortest distances from each landmark to all nodes as an embedding. To answer a shortest distance query, the precomputed distances from the landmarks to the two query nodes are used to compute an approximate shortest distance based on the triangle inequality. In this paper, we analyze the factors…

Read More

Fast Nearest Neighbor Search with Keywords

Fast Nearest Neighbor Search with Keywords Conventional spatial queries, such as range search and nearest neighbor retrieval, involve only conditions on objects geometric properties. Today, many modern applications call for novel forms of queries that aim to find objects satisfying both a spatial predicate, and a predicate on their associated texts. For example, instead of considering all the restaurants, a nearest neighbor query would instead ask for the restaurant that is the closest among those whose menus contain all at the same time. Currently, the best solution to such queries…

Read More

Localization of wireless sensor networks in the wild: pursuit of ranging quality

Localization of wireless sensor networks in the wild: pursuit of ranging quality Networking June 2013 Localization is a fundamental issue of wireless sensor networks that has been extensively studied in the literature. Localization of wireless sensor nodes in the wild remains very challenging due to various interfering factors. A Combined and Differentiated Localization (CDL) is proposed approach for localization that exploits the strength of range-free approaches and range-based approaches using received signal strength indicator (RSSI). A critical observation is that ranging quality greatly impacts the overall localization accuracy. To achieve…

Read More

Secure Data Retrieval for Decentralized Disruption-Tolerant Military Networks

Secure Data Retrieval for Decentralized Disruption-Tolerant Military Networks Mobile nodes in military environments such as a battlefield or a hostile region are likely to suffer from intermittent network connectivity and frequent partitions. Disruption-tolerant network (DTN) technologies are becoming successful solutions that allow wireless devices carried by soldiers to communicate with each other and access the confidential information or command reliably by exploiting external storage nodes. Some of the most challenging issues in this scenario are the enforcement of authorization policies and the policies update for secure data retrieval. Ciphertext-policy attribute-based…

Read More

Designing an Efficient Image Encryption-Then-Compression System via Prediction Error Clustering

Designing an Efficient Image Encryption-Then-Compression System via Prediction Error Clustering and Random Permutation Image encryption has to be conducted prior to image compression in many applications. This has led to the problem of how to design a pair of image encryption and compression algorithms such that compressing the encrypted images can still be efficiently performed. In this paper, we design a highly efficient image encryption-then-compression (ETC) system, where both lossless and lossy compression are considered. The proposed image encryption scheme operated in the prediction error domain is shown to be…

Read More

Decentralized Access Control with Anonymous Authentication of Data Stored in Clouds

Decentralized Access Control with Anonymous Authentication of Data Stored in Clouds Technology Used: Dot net A new decentralized access control scheme is proposed for secure data storage in clouds that supports anonymous authentication. In the proposed scheme, the cloud verifies the authenticity of the series without knowing the user’s identity before storing data. Access control is enabled, in which only valid users are able to decrypt the stored information. The scheme prevents replay attacks and supports creation, modification, and reading data stored in the cloud. Authentication and access control scheme…

Read More