The Experts below are selected from a list of 18759 Experts worldwide ranked by ideXlab platform

Jon Weissman - One of the best experts on this subject based on the ideXlab platform.

  • wiera policy driven multi tiered geo distributed Cloud Storage System
    IEEE Transactions on Parallel and Distributed Systems, 2020
    Co-Authors: Nan Qin, Abhishek Chandra, Jon Weissman
    Abstract:

    Multi-tiered geo-distributed Cloud Storage Systems must tame complexity at many levels: uniform APIs for Storage access, supporting flexible Storage policies that meet a wide array of application metrics, determining an optimal data placement, handling uncertain network dynamics and access dynamism, and operating across many levels of heterogeneity both within and across data-centers (DCs). In this paper, we present an integrated solution called Wiera. Wiera enables the specification of data management policies both within a local DC and across DCs. Such policies enable the user to optimize for cost, performance, reliability, durability, and consistency, and to express their tradeoffs. In addition, Wiera determines an optimal data placement for the user to meet their desired tradeoffs easily in such an environment. A key aspect of Wiera is first-class support for dynamism due to network, workload, and access patterns changes. As far as we know, Wiera is the first geo-distributed Cloud Storage System which handles dynamism actively at run-time. Wiera allows unmodified applications to reap the benefits of flexible data/Storage policies by externalizing the policy specification. We show how Wiera enables a rich specification of dynamic policies using a concise notation and describe the design and implementation of the System. We have implemented a Wiera prototype on multiple Cloud environments, AWS and Azure, that illustrates potential benefits from managing dynamics and in using multiple Cloud Storage tiers both within and across DCs.

  • wiera towards flexible multi tiered geo distributed Cloud Storage instances
    High Performance Distributed Computing, 2016
    Co-Authors: Abhishek Chandra, Jon Weissman
    Abstract:

    Geo-distributed Cloud Storage Systems must tame complexity at many levels: uniform APIs for Storage access, supporting flexible Storage policies that meet a wide array of application metrics, handling uncertain network dynamics and access dynamism, and operating across many levels of heterogeneity both within and across data-centers. In this paper, we present an integrated solution called Wiera. Wiera extends our earlier Cloud Storage System, Tiera, that is targeted to multi-tiered policy-based single Cloud Storage, to the wide-area and multiple data-centers (even across different providers). Wiera enables the specification of global data management policies built on top of local Tiera policies. Such policies enable the user to optimize for cost, performance, reliability, durability, and consistency, both within and across data-centers, and to express their tradeoffs. A key aspect of Wiera is first-class support for dynamism due to network, workload, and access patterns changes. Wiera policies can adapt to changes in user workload, poorly performing data tiers, failures, and changes in user metrics (e.g., cost). Wiera allows unmodified applications to reap the benefits of flexible data/Storage policies by externalizing the policy specification. As far as we know, Wiera is the first geo-distributed Cloud Storage System which handles dynamism actively at run-time. We show how Wiera enables a rich specification of dynamic policies using a concise notation and describe the design and implementation of the System. We have implemented a Wiera prototype on multiple Cloud environments, AWS and Azure, that illustrates potential benefits from managing dynamics and in using multiple Cloud Storage tiers both within and across data-centers.

Wan Choi - One of the best experts on this subject based on the ideXlab platform.

  • optimal Storage allocation for wireless Cloud caching Systems with a limited sum Storage capacity
    IEEE Transactions on Wireless Communications, 2016
    Co-Authors: Bi Hong, Wan Choi
    Abstract:

    In wireless Cloud Storage Systems, the recovery failure probability depends on not only wireless channel conditions but also Storage size of each distributed Storage node. For an efficient utilization of limited Storage capacity and the performance characterization of allocation strategies, we asymptotically analyze the recovery failure probability of a wireless Cloud Storage System with a sum Storage capacity constraint for both high signal-to-noise ratio (SNR) regime and low SNR regime. Then, we find the optimal Storage allocation strategy across distributed Storage nodes in terms of the asymptotic recovery failure probability. Our analysis reveals that the maximal symmetric allocation is optimal for high SNR regime and the minimal allocation (with $\lfloor T\rfloor $ complete Storage nodes and an incomplete Storage node) is optimal for low SNR regime, where $T$ is the sum Storage capacity. Based on the numerical investigation, we also show that in intermediate SNR regime, a balance allocation between the minimal allocation and the maximal symmetric allocation would not be required if we select one between them according to SNR.

  • optimal Storage allocation for wireless Cloud caching Systems with a limited sum Storage capacity
    arXiv: Information Theory, 2016
    Co-Authors: Bi Hong, Wan Choi
    Abstract:

    In wireless Cloud Storage Systems, the recovery failure probability depends on not only wireless channel conditions but also Storage size of each distributed Storage node. For an efficient utilization of limited Storage capacity and the performance characterization of allocation strategies, we asymptotically analyze the recovery failure probability of a wireless Cloud Storage System with a sum Storage capacity constraint for both high SNR regime and low SNR regime. Then, we find the optimal Storage allocation strategy across distributed Storage nodes in terms of the asymptotic recovery failure probability. Our analysis reveals that the maximal symmetric allocation is optimal for high SNR regime and the minimal allocation (with $\lfloor T\rfloor$ complete Storage nodes and an incomplete Storage node) is optimal for low SNR regime, where $T$ is the sum Storage capacity. Based on the numerical investigation, we also show that in intermediate SNR regime, a balance allocation between the minimal allocation and the maximal symmetric allocation would not be required if we select one between them according to SNR.

Zhenfu Cao - One of the best experts on this subject based on the ideXlab platform.

  • traceable and undeniable ciphertext policy attribute based encryption for Cloud Storage service
    International Journal of Distributed Sensor Networks, 2019
    Co-Authors: Yongjuan Wang, Zhenfu Cao, Jian Lin, Xiangyu Wang
    Abstract:

    Ciphertext-policy attribute-based encryption is a promising mechanism with fine-grained access control for Cloud Storage System. However, there is a long-lasting problem of key abuse that a user ma...

  • traceable and undeniable ciphertext policy attribute based encryption for Cloud Storage service
    International Journal of Distributed Sensor Networks, 2019
    Co-Authors: Yongjuan Wang, Zhenfu Cao, Jian Lin, Xiangyu Wang
    Abstract:

    Ciphertext-policy attribute-based encryption is a promising mechanism with fine-grained access control for Cloud Storage System. However, there is a long-lasting problem of key abuse that a user may share its decryption key and a semi-honest authority may illegally issue decryption keys for unauthorized users for profits. To address this problem, we propose an accountable ciphertext-policy attribute-based encryption scheme. In our construction, there are two authorities to issue keys for users, but they cannot decrypt any ciphertexts without collusion. A shared key can be effectively traced, and if the traced identity claims that it is innocent, an auditor can publicly audit who will be responsible for the shared key. Compared with existing accountable ciphertext-policy attribute-based encryption schemes, the proposed scheme is more practical from the two aspects: (1) a user can normally request for a decryption key along with a short signature, and no additional interaction between users and authorities ...

  • encryption switching service securely switch your encrypted data to another format
    IEEE Transactions on Services Computing, 2018
    Co-Authors: Peng Jiang, Changyu Dong, Jianting Ning, Kaitai Liang, Jiageng Chen, Zhenfu Cao
    Abstract:

    Big data analytics has been regarded as a promising technology to yield better insights into future development by government and industry. Data collection and aggregation are necessary steps to enable data analysis. However, data may be dispersed across multiple places and in different formats. Even worse, data can be encrypted under different encryption mechanisms when different data owners try to secure their data. This makes data aggregation very difficult, if not impossible, especially when the encryption keys cannot be shared for various reasons. In this paper, we take the first step in addressing this problem. More specifically, we propose a new notion of cross-domain encryption switching that bridges two well-studied encryption mechanisms, namely traditional public key encryption and identity-based encryption. As of independent interest, our notion supports keyword search over encrypted data. We provide a provably-secure instantiation satisfying the notion, and further present the efficiency analysis to show the scalability. Our proposed scheme is applicable in multi-domain Cloud Storage System.

Jinguang Han - One of the best experts on this subject based on the ideXlab platform.

  • user collusion avoidance cp abe with efficient attribute revocation for Cloud Storage
    IEEE Systems Journal, 2018
    Co-Authors: Wei Yao, Jinguang Han, Yichen Zhang, Jian Shen
    Abstract:

    Attribute-based encryption (ABE) can guarantee confidentiality and achieve fine-grained data access control in a Cloud Storage System. Due to the fact that every attribute in ABE may be shared by multiple users and each user holds multiple attributes, any single-attribute revocation for some user may affect the other users with the same attribute in the System. Therefore, how to revoke attribute efficiently is an important and challenging problem in ABE schemes. In order to solve above problems, we first give a concrete attack to the existing ABE scheme with attribute revocation. Then, we formalize the definition and security model, which model collusion attack executed by the existing users cooperating with the revoked users. Finally, we present a user collusion avoidance ciphertext-policy ABE scheme with efficient attribute revocation for the Cloud Storage System. The problem of attribute revocation is solved efficiently by exploiting the concept of an attribute group. When an attribute is revoked from a user, the group manager updates other users’ secret keys. Furthermore, we prove that the proposed scheme is secure against collusion attack launched by the existing users and the revoked users. The security of the proposed scheme is reduced to the computational Diffie–Hellman assumption.

  • flexible and fine grained attribute based data Storage in Cloud computing
    IEEE Transactions on Services Computing, 2017
    Co-Authors: Wei Yao, Yichen Zhang, Huiling Qian, Jinguang Han
    Abstract:

    With the development of Cloud computing, outsourcing data to Cloud server attracts lots of attentions. To guarantee the security and achieve flexibly fine-grained file access control, attribute based encryption (ABE) was proposed and used in Cloud Storage System. However, user revocation is the primary issue in ABE schemes. In this article, we provide a ciphertext-policy attribute based encryption (CP-ABE) scheme with efficient user revocation for Cloud Storage System. The issue of user revocation can be solved efficiently by introducing the concept of user group. When any user leaves, the group manager will update users’ private keys except for those who have been revoked. Additionally, CP-ABE scheme has heavy computation cost, as it grows linearly with the complexity for the access structure. To reduce the computation cost, we outsource high computation load to Cloud service providers without leaking file content and secret keys. Notably, our scheme can withstand collusion attack performed by revoked users cooperating with existing users. We prove the security of our scheme under the divisible computation Diffie-Hellman assumption. The result of our experiment shows computation cost for local devices is relatively low and can be constant. Our scheme is suitable for resource constrained devices.

Bi Hong - One of the best experts on this subject based on the ideXlab platform.

  • optimal Storage allocation for wireless Cloud caching Systems with a limited sum Storage capacity
    IEEE Transactions on Wireless Communications, 2016
    Co-Authors: Bi Hong, Wan Choi
    Abstract:

    In wireless Cloud Storage Systems, the recovery failure probability depends on not only wireless channel conditions but also Storage size of each distributed Storage node. For an efficient utilization of limited Storage capacity and the performance characterization of allocation strategies, we asymptotically analyze the recovery failure probability of a wireless Cloud Storage System with a sum Storage capacity constraint for both high signal-to-noise ratio (SNR) regime and low SNR regime. Then, we find the optimal Storage allocation strategy across distributed Storage nodes in terms of the asymptotic recovery failure probability. Our analysis reveals that the maximal symmetric allocation is optimal for high SNR regime and the minimal allocation (with $\lfloor T\rfloor $ complete Storage nodes and an incomplete Storage node) is optimal for low SNR regime, where $T$ is the sum Storage capacity. Based on the numerical investigation, we also show that in intermediate SNR regime, a balance allocation between the minimal allocation and the maximal symmetric allocation would not be required if we select one between them according to SNR.

  • optimal Storage allocation for wireless Cloud caching Systems with a limited sum Storage capacity
    arXiv: Information Theory, 2016
    Co-Authors: Bi Hong, Wan Choi
    Abstract:

    In wireless Cloud Storage Systems, the recovery failure probability depends on not only wireless channel conditions but also Storage size of each distributed Storage node. For an efficient utilization of limited Storage capacity and the performance characterization of allocation strategies, we asymptotically analyze the recovery failure probability of a wireless Cloud Storage System with a sum Storage capacity constraint for both high SNR regime and low SNR regime. Then, we find the optimal Storage allocation strategy across distributed Storage nodes in terms of the asymptotic recovery failure probability. Our analysis reveals that the maximal symmetric allocation is optimal for high SNR regime and the minimal allocation (with $\lfloor T\rfloor$ complete Storage nodes and an incomplete Storage node) is optimal for low SNR regime, where $T$ is the sum Storage capacity. Based on the numerical investigation, we also show that in intermediate SNR regime, a balance allocation between the minimal allocation and the maximal symmetric allocation would not be required if we select one between them according to SNR.