The Experts below are selected from a list of 12063 Experts worldwide ranked by ideXlab platform

Ludmila Cherkasova - One of the best experts on this subject based on the ideXlab platform.

  • providing resource allocation and performance isolation in a shared streaming media Hosting Service
    ACM Symposium on Applied Computing, 2004
    Co-Authors: Ludmila Cherkasova, Wenting Tang
    Abstract:

    The trend toward media content Hosting is seeing a significant growth as more rich media is used in the enterprise environment and as it becomes mission critical for businesses. A shared media Hosting Service supports the illusion that each hosted Service has its own media server, when, in reality, multiple "logical hosts" may share one physical host. For such a shared media Hosting Service, the ability to guarantee a specified share of server resources to a particular hosted Service is very important. We present SharedMediaGuard - a shared media Hosting infrastructure that can efficiently allocate the predefined shares of server resources to the hosted media Services. The proposed solution is based on a unified cost function that uses a single value to reflect the combined resource requirement such as CPU, bandwidth and memory necessary to support a particular media stream depending on the stream bit rate and type of access (memory file access or disk file access). Our evaluation of SharedMediaGuard compared to the traditional, disk-based allocation strategy that assumes all content must be served from disk reveals a factor of two improvement in server throughput while providing performance isolation and QoS guarantees among the hosted Services.

  • optimizing a content aware load balancing strategy for shared web Hosting Service
    Modeling Analysis and Simulation On Computer and Telecommunication Systems, 2000
    Co-Authors: Ludmila Cherkasova, Shankar Ponnekanti
    Abstract:

    FLEX is a new scalable "locality-aware" solution for achieving both load balancing and efficient memory usage on a cluster of machines Hosting several Web sites. FLEX allocates the sites to different machines in the cluster based on their traffic characteristics. We propose a set of new methods and algorithms (Simple+, Advanced and Advanced+) to improve the allocation of the Web sites to different machines. New methods show additional performance benefits as compared to the original Simple strategy. Experiments show that FLEX outperforms traditional load-balancing solutions by 50% to 100% (in throughput), even for a four-node cluster. The miss ratio is improved 2-3 times.

Tanya M Kelley - One of the best experts on this subject based on the ideXlab platform.

Tie Qiu - One of the best experts on this subject based on the ideXlab platform.

  • an efficient protocol with bidirectional verification for storage security in cloud computing
    IEEE Access, 2016
    Co-Authors: Bin Feng, Cheng Guo, Hui Shi, Tie Qiu
    Abstract:

    In cloud computing, data owners host their data on cloud servers, and users (data consumers) can access the data from the cloud servers. This new paradigm of data Hosting Service also introduces new security challenges that require an independent auditing Service to check the integrity of the data in the cloud. Some existing methods for checking the integrity of the data cannot handle this problem efficiently and they cannot deal with the error condition. Thus, a secure and efficient dynamic auditing protocol should reject requests that are made with improper authentication. In addition, an excellent remote data authentication method should be able to collect information for statistical analysis, such as validation results. In this paper, first we design an auditing framework for cloud storage systems and propose an efficient and privacy-preserving auditing protocol. Then, we extend our auditing protocol to support dynamic data operations, which is efficient and has been proven to be secure in the random oracle model. We extended our auditing protocol further to support bidirectional authentication and statistical analysis. In addition, we use a better load distribution strategy, which greatly reduces the computational overhead of the client. Last, we provide an error response scheme, and our experiments show that our solution has good error-handling ability and offers lower overhead expenses for computation and communication than other approaches.

Shigeo Morishima - One of the best experts on this subject based on the ideXlab platform.

  • automatic music video generating system by remixing existing contents in video Hosting Service based on hidden markov model
    International Conference on Computer Graphics and Interactive Techniques, 2012
    Co-Authors: Hayato Ohya, Shigeo Morishima
    Abstract:

    User-generated music video clip called MAD movie, which is a derivative (mixture or combination) of some original video clips, are gaining popularity on the web and a lot of them have been uploaded and are available on video Hosting web Services. Such a MAD music video clip consists of audio signals and video frames taken from other original video clips. In a MAD video clip, good music-to-image synchronization with respect to rhythm, impression, and context is important. Although it is easy to enjoy watching MAD videos, it is not easy to generate them. It is because a creator needs high-performance video editing software and spends a lot of time for editing video. Additionally, a creator is required video editing skill. DanceReProducer (Nakano et al [2011]) is a dance video authoring system that can automatically generate dance video appropriate to music by reusing existing dance video sequences. It trains correspondence relationship between music and video. However, DanceReProducer cannot train video sequence information because it only trains one-bar correspondence relationship. So we improved DanceReProducer to consider video sequence information by using Markov chain of latent variable and Forward Viterbi algorithm.

Yasuichi Nakayama - One of the best experts on this subject based on the ideXlab platform.

  • secure and high performance web server system for shared Hosting Service
    International Conference on Parallel and Distributed Systems, 2006
    Co-Authors: Daisuke Hara, Yasuichi Nakayama
    Abstract:

    We developed Hi-sap, a Web server system that ensures the security in a server and has high performance when processing dynamic content. In existing servers, server embedded programs cannot be used safely in large-scale environments like a shared Hosting Service. These problems occur because server processes run under the privilege of an identical user. For example, server embedded interpreters are commonly used to improve performance in processing dynamic content, like Weblogs and wikis. However, other customers that share the same server can steal, delete, and tamper with data files of Weblogs and wikis. To solve these problems, we designed a new Web server system, Hi-sap. In the system, Web objects that are stored in a server are divided into partitions. Server processes run under the privilege of different users in every partition. We implemented Hi-sap on a Linux OS and tested the effectiveness of the system. Experimental results show that Hi-sap has high performance and scalability.

  • design and implementation of a web server for a Hosting Service
    IMSA, 2005
    Co-Authors: Daisuke Hara, Ryota Ozaki, Kazuki Hyoudou, Yasuichi Nakayama
    Abstract:

    A web server named Harache is presented. The server runs under the authority of the file owner. Existing servers have problems that occur because of the user authority during execution. When a program that uses a server embedded interpreter, for example PHP, creates data files, the owner of the created files is the special user account that runs a server. Therefore, other users that share the same server can steal and delete these data files. In particular, these problems are serious for a Hosting Service where many users share a server. Harache has server processes that run under the authority of the file owner. Therefore, Harache can solve these problems that occur because of the user authority. Harache can be used for a Hosting Service where many people share a server with a reverse proxy. We implemented Harache on a Linux OS with SELinux and performed evaluation experiments to test the system’s effectiveness. Experimental results show that Harache has high performance and scalability.