scispace - formally typeset
Search or ask a question
Topic

Data access

About: Data access is a research topic. Over the lifetime, 13141 publications have been published within this topic receiving 172859 citations. The topic is also known as: Data access.


Papers
More filters
Patent
12 May 1998
TL;DR: In this paper, a cluster implements a virtual disk system that provides each node of a cluster access to each storage device of the cluster, and a cluster transport interface is provided that establishes links between the nodes and manages the links.
Abstract: A cluster implements a virtual disk system that provides each node of the cluster access to each storage device of the cluster. The virtual disk system provides high availability such that a storage device may be accessed and data access requests are reliably completed even in the presence of a failure. To ensure consistent mapping and file permission data among the nodes, data are stored in a highly available cluster database. Because the cluster database provides consistent data to the nodes even in the presence of a failure, each node will have consistent mapping and file permission data. A cluster transport interface is provided that establishes links between the nodes and manages the links. Messages received by the cluster transports interface are conveyed to the destination node via one or more links. The configuration of a cluster may be modified during operation. Prior to modifying the configuration, a reconfiguration procedure suspends data access requests and waits for pending data access requests to complete. The reconfiguration is performed and the mapping is modified to reflect the new configuration. The node then updates the internal representation of the mapping and resumes issuing data access requests.

74 citations

Proceedings ArticleDOI
08 Jul 2014
TL;DR: This paper builds a model framework that can accommodate a range of different objectives for multi-objective optimization for placing users' data over multiple clouds for socially aware services, and proposes an optimization approach that decomposes the original problem into two simpler subproblems and solves them alternately in multiple rounds.
Abstract: Socially aware services often have a large user base and data of users have to be partitioned and replicated over multiple geographically distributed clouds. Choosing in which cloud to place data, however, is difficult. Effective data placements entail meeting multiple system objectives, including reducing the usage of cloud resources, providing good service quality to users, and even minimizing the carbon footprint, while facing critical challenges such as the interconnection of social data, the conflicting requirements of different objectives, and the customized multi-cloud data access policies. In this paper, we study multi-objective optimization for plac- ing users' data over multiple clouds for socially aware services. We build a model framework that can accommodate a range of different objectives, and based on this model we formulate the optimization problem. Leveraging graph cuts, we propose an optimization approach that decomposes our original problem into two simpler subproblems and solves them alternately in multiple rounds. We carry out evaluations using a large group of real- world geographically distributed users with realistic interactions, and place users' data over 10 clouds all across the US. We demonstrate results that are significantly superior to standard and de facto methods in all objectives, and also show that our approach is capable of exploring trade-offs among objectives, converges fast and scales to a huge user base.

74 citations

Proceedings ArticleDOI
Takahiro Hara1
04 Nov 2002
TL;DR: This paper proposes three caching strategies in which clients cooperatively cache broadcast data items that shorten the average response time for data access by replacing cached items based on their access frequencies, the network topology, and the time remaining until each item is broadcast next.
Abstract: Recent advances in computer and wireless communication technologies have increased interest in push-based information systems in which a server repeatedly broadcasts data to clients through a broadband channel. In this paper, assuming an environment where clients in push-based information systems construct ad hoc networks, we propose three caching strategies in which clients cooperatively cache broadcast data items. These strategies shorten the average response time for data access by replacing cached items based on their access frequencies, the network topology, and the time remaining until each item is broadcast next. We also show the results of simulation experiments conducted to evaluate the performance of our proposed strategies.

74 citations

Journal ArticleDOI
TL;DR: SAIL represents an ongoing programme of work to develop and maintain an extensive, whole population data resource for research and continually endeavour to demonstrate trustworthiness to support data provider assurance and public acceptability in data use.
Abstract: Background The Secure Anonymised Information Linkage (SAIL) Databank is a national data safe haven of de‑identified datasets principally about the population of Wales, made available in anonymised form to researchers across the world. It was established to enable the vast arrays of data collected about individuals in the course of health and other public service delivery to be made available to answer important questions that could not otherwise be addressed without prohibitive effort. The SAIL Databank is the bedrock of other funded centres relying on the data for research. Approach SAIL is a data repository surrounded by a suite of physical, technical and procedural control measures embodying a proportionate privacy-by-design governance model, informed by public engagement, to safeguard the data and facilitate data utility. SAIL operates on the UK Secure Research Platform (SeRP), which is a customisable technology and analysis platform. Researchers access anonymised data via this secure research environment, from which results can be released following scrutiny for disclosure risk. SAIL data are being used in multiple research areas to evaluate the impact of health and social exposures and policy interventions. Discussion Lessons learned and their applications include: managing evolving legislative and regulatory requirements; employing multiple, tiered security mechanisms; working hard to increase analytical capacity efficiency; and developing a multi-faceted programme of public engagement. Further work includes: incorporating new data types; enabling alternative means of data access; and developing further efficiencies across our operations. Conclusion SAIL represents an ongoing programme of work to develop and maintain an extensive, whole population data resource for research. Its privacy-by-design model and UK SeRP technology have received international acclaim, and we continually endeavour to demonstrate trustworthiness to support data provider assurance and public acceptability in data use. We strive for further improvement and continue a mutual learning process with our contemporaries in this rapidly developing field.

74 citations

Patent
12 Sep 2012
TL;DR: In this paper, a system and method to provide location-based levels of data protection is described, which includes: receiving, by a receiver, login credentials of a user of a mobile device; authenticating, by use of a policy server, a credentials-based level of data access as configured by a policy; retrieving, by using a geo-location module, a location of the mobile device.
Abstract: System and method to provide location-based levels of data protection, the method including: receiving, by a receiver, login credentials of a user of a mobile device; authenticating, by use of a policy server, a credentials-based level of data access as configured by a policy; retrieving, by a geo-location module, a location of the mobile device; determining, by use of the policy server, a location-based level of data access as configured by the policy; and granting sensitive data access based upon a more restrictive limitation of the credentials-based level of data access and the location-based level of data access.

74 citations


Network Information
Related Topics (5)
Software
130.5K papers, 2M citations
86% related
Cloud computing
156.4K papers, 1.9M citations
86% related
Cluster analysis
146.5K papers, 2.9M citations
85% related
The Internet
213.2K papers, 3.8M citations
85% related
Information system
107.5K papers, 1.8M citations
83% related
Performance
Metrics
No. of papers in the topic in previous years
YearPapers
202351
2022125
2021403
2020721
2019906
2018816