Showing papers on "Data access published in 2007"

Cellular Census: Explorations in Urban Data Collection

Abstract: Much of our understanding of urban systems comes from traditional data collection methods such as surveys by person or phone. These approaches can provide detailed information about urban behaviors, but they're hard to update and might limit results to "snapshots in time." In the past few years, some innovative approaches have sought to use mobile devices to collect spatiotemporal data. But little research has been done to develop and analyze the much larger samples of existing data generated daily by mobile networks. The most common explanation for this is that the challenge of data-sharing with the telecommunications industry has hampered data access. However, in early 2006, a collaboration between Telecom Italia, which serves 40 percent of the Roman market, and MIT's SKNSEable City Laboratory (http://senseable.mit.edu) allowed unprecedented access to aggregate mobile phone data from Rome. Here, we explore how researchers might be able to use data for an entire metropolitan region to analyze urban dynamics.

Extensible, filtered lists for mobile device user interface

Abstract: The subject disclosure pertains to systems and methods for providing an improved user interface for mobile devices. Access to data and services from multiple software applications can be provided through a group or list of items. Each group or list can include multiple items, which can be associated with data or tasks from multiple applications. The set of groups of items can be both customizable and extensible to allow users to locate and utilize data and tasks relevant to the particular user. The set of item groups can provide users with a filtered view of content available through the mobile device, enhancing access to subset of data and tasks available on the mobile device.

On scheduling vehicle-roadside data access

Abstract: As vehicular networks become popular, more and more people want to access data from their vehicles. When many vehicles want to access data through a roadside unit, data scheduling becomes an important issue. In this paper, we identify some challenges in vehicle-roadside data access. As vehicles move pretty fast, the requests should be served quickly. Also, vehicles may upload data to the roadside unit, and hence the download and upload requests compete for the same bandwidth. To address these challenges, we propose several scheduling schemes. We first propose a basic scheduling scheme called D*S to consider both service deadline and data size. We then enhance it by using a single broadcast to serve multiple requests. Finally, we identify the effects of upload requests on data quality, and propose a Two-Step scheduling scheme to provide a balance between serving download and update requests. Simulation results show that the Two-Step scheduling scheme outperforms other scheduling schemes.

Smart integration engine and metadata-oriented architecture for automatic eii and business integration

Abstract: The present invention discloses systems and methods for automating the EII, using a smart integration engine based on metadata. On-line execution (i.e. data access, retrieval, or update) is automated by integrating heterogeneous data sources via a centralized smart engine based on metadata of all data sources managed in a metadata repository. The data-source assets are mapped to business metadata (terminology) giving programmers the ability to use business terms, and overcome technical terms. IT departments can use the business-level terms for easy and fast programming of all services “at the business level”. The integration is performed by the engine (via pre-configuration) automatically, dynamically, and on-line, regardless of topology or technology changes, without user or administrator intervention. MDOA is a high-level concept in which the metadata maps the technical low-level terms to business high-level terms. MDOA is used for seamless integration of a fully-distributed organization with many data sources and technologies.

TimeLine: Visualizing Integrated Patient Records

Abstract: An increasing amount of data is now accrued in medical information systems; however, the organization of this data is still primarily driven by data source, and does not support the cognitive processes of physicians. As such, new methods to visualize patient medical records are becoming imperative in order to assist physicians with clinical tasks and medical decision-making. The TimeLine system is a problem-centric temporal visualization for medical data: information contained with medical records is reorganized around medical disease entities and conditions. Automatic construction of the TimeLine display from existing clinical repositories occurs in three steps: 1. data access, which uses an extensible Markup Language (XML) data representation to handle distributed, heterogeneous medical databases; 2. data mapping and reorganization, reformulating data into hierarchical, problem-centric views; and 3. data visualization, which renders the display to a target presentation platform. Leveraging past work, we describe the latter two components of the TimeLine system in this paper, and the issues surrounding the creation of medical problems lists and temporal visualization of medical data. A driving factor in the development of TimeLine was creating a foundation upon which new data types and the visualization metaphors could be readily incorporated.

Comparing anomaly detection techniques for HTTP

Abstract: Much data access occurs via HTTP, which is becoming a universal transport protocol. Because of this, it has become a common exploit target and several HTTP specific IDSs have been proposed as a response. However, each IDS is developed and tested independently, and direct comparisons are difficult. We describe a framework for testing IDS algorithms, and apply it to several proposed anomaly detection algorithms, testing using identical data and test environment. The results show serious limitations in all approaches, and we make predictions about requirements for successful anomaly detection approaches used to protect web servers.

Method and System for High Performance Integration, Processing and Searching of Structured and Unstructured Data Using Coprocessors

Abstract: Disclosed herein is a method and system for integrating an enterprise's structured and unstructured data to provide users and enterprise applications with efficient and intelligent access to that data. Queries can be directed toward both an enterprise's structured and unstructured data using standardized database query formats such as SQL commands. A coprocessor can be used to hardware-accelerate data processing tasks (such as full-text searching) on unstructured data as necessary to handle a query. Furthermore, traditional relational database techniques can be used to access structured data stored by a relational database to determine which portions of the enterprise's unstructured data should be delivered to the coprocessor for hardware-accelerated data processing.

Generation of query and update views for object relational mapping

Abstract: A data access architecture may includes a mapping architecture for mapping data as may be used by an application to data as persisted in a database. Such a mapping architecture uses two types of “mapping views”—one for translating queries and the other for translating updates. A mechanism is provided that automatically generates query and update views from high-level mapping specifications. A validation may be performed to ensure that a mapping specification, when used in conjunction with a mapping architecture, allows data to “roundtrip” from the application to the database, without loss of data.

Compiling mappings to bridge applications and databases

Abstract: Translating data and data access operations between applications and databases is a longstanding data management problem. We present a novel approach to this problem, in which the relationship between the application data and the persistent storage is specified using a declarative mapping, which is compiled into bidirectional views that drive the data transformation engine. Expressing the application model as a view on the database is used to answer queries, while viewing the database in terms of the application model allows us to leverage view maintenance algorithms for update translation. This approach has been implemented in a commercial product. It enables developers to interact with a relational database via a conceptual schema and an object oriented programming surface. We outline the implemented system and focus on the challenges of mapping compilation, which include rewriting queries under constraints and supporting non-relational constructs.

Mapping architecture with incremental view maintenance

Abstract: A data access architecture is provided that includes a mapping architecture for mapping data as may be used by an application to data as persisted in a database. The mapping architecture makes use of two types of mapping views—a query view that helps in translating queries and an update view that helps in translating updates. Incremental view maintenance can be used to translate data between the application and database.

Controlling access to storage resources by using access pattern based quotas

Abstract: An apparatus and a method that limits a user's access to data of the storage system based on an access quota. The method may include determining an access pattern of data access requests to storage resources by a user, and comparing the access pattern of the user against an access quota, as defined by an access policy. Based on the comparison, if the user's access to the storage resources has exceeded the access quota, the storage system can limit access to the user to the storage resources.

System and method for providing secured access to mobile devices

Abstract: A system and method for providing secured access of a mobile device is disclosed herein. Access to data included in the mobile device is permitted when the presence of an authentication device having the proper authentication information is received by the mobile device.

Mapping conversion method between data access level Xml format data and relational data

Abstract: This invention provides a mapping converting method for format data and relation data of a data access layer Xml including two periods of designing time and operation time, in which, at the designing time period, a model is set up based on the data structure of the relation data and mapping and conversion of the object and the relation data to be described as a data object and data model, and the data object means that the relation data sets up a model and abstracts the data structure of the list and view in the database to describe its name and field attribute, at the operation period, the data access an engine to structure SQL sentences dynamically for accessing database according to the element data information defined in designing and input data information to finish function of data access layer of increasing, deleting, correcting and checking automatically.

Anatomy of the ADO.NET entity framework

Abstract: Traditional client-server applications relegate query and persistence operations on their data to database systems. The database system operates on data in the form of rows and tables, while the application operates on data in terms of higher-level programming language constructs (classes, structures etc.). The impedance mismatch in the data manipulation services between the application and the database tier was problematic even in traditional systems. With the advent of service-oriented architectures (SOA), application servers and multi-tier applications, the need for data access and manipulation services that are well-integrated with programming environments and can operate in any tier has increased tremendously. Microsoft's ADO.NET Entity Framework is a platform for programming against data that raises the level of abstraction from the relational level to the conceptual (entity) level, and thereby significantly reduces the impedance mismatch for applications and data-centric services. This paper describes the key aspects of the Entity Framework, the overall system architecture, and the underlying technologies.

Method and apparatus for managing storage of data

Abstract: In a method and apparatus for storage of data, data is stored The stored data is checked, for example periodically and/or on data access, for development of a fault in the stored data If a fault is detected, at least one of: (i) increased protection and (ii) increased error correction is applied to at least some of the remaining fault-free data

Live data center migration across WANs: a robust cooperative context aware approach

Abstract: A significant concern for Internet-based service providers is the continued operation and availability of services in the face of outages, whether planned or unplanned. In this paper we advocate a cooperative, context-aware approach to data center migration across WANs to deal with outages in a non-disruptive manner. We specifically seek to achieve high availability of data center services in the face of both planned and unanticipated outages of data center facilities. We make use of server virtualization technologies to enable the replication and migration of server functions. We propose new network functions to enable server migration and replication across wide area networks (e.g., the Internet), and finally show the utility of intelligent and dynamic storage replication technology to ensure applications have access to data in the face of outages with very tight recovery point objectives.

A Purpose-Based Access Control Model

Abstract: Achieving privacy preservation in a data-sharing computing environment is a challenging problem. The requirements for a privacy preserving data access policy should be formally specified in order to be able to establish consistency between the privacy policy and its purported implementation in practice. Previous work has shown that when specifying a privacy policy, the notion of purpose should be used as the basis for access control. A privacy policy should ensure that data can only be used for its intended purpose, and the access purpose should be compliant with the data's intended purpose. This paper presents a mechanism to specify privacy policy using VDM. The entities in the purpose-based access control model are specified, the invariants corresponding to the privacy requirements in privacy policy are specified, and the operations in the model and their proof obligations are defined and investigated.

EnviroStore: A Cooperative Storage System for Disconnected Operation in Sensor Networks

Abstract: This paper presents a new cooperative storage system for sensor networks geared for disconnected operation (where sensor nodes do not have a connected path to a basestation). The goal of the system is to maximize its data storage capacity by appropriately distributing storage utilization and opportunistically offloading data to external devices when possible. The system is motivated by the observation that a large category of sensor network applications, such as environmental data logging, does not require real-time data access. Such networks generally operate in a disconnected mode. Rather than focusing on multihop routing to a basestation, an important concern becomes (i) to maximize the effective storage capacity of the disconnected sensor network such that it accommodates the most data, and (ii) to take the best advantage of data upload opportunities when they become available to relieve network storage. The storage system described in this paper achieves the above goals, leading to significant improvements in the amount of data collected compared to non-cooperative storage. It is implemented in nesC for TinyOS and evaluated in TOSSIM through various application scenarios.

Secure compartmented mode knowledge management portal

Abstract: A layered defense-in-depth knowledge-based data management comprises a reception zone for authenticating a user for access to the system and an operations zone for adjudicating on a user level access to data objects stored in the system database. In addition, the data management comprises a security zone for issuing certificates of accessibility for defined users and a screening zone to interrogate data packets during processing thereof. The first line of defense is firewall protection and packet filtering preceding the reception zone.

View Maintenance Rules for an Update Pipeline of an Object-Relational Mapping (ORM) Platform

Abstract: A database update pipeline may be incorporated into a data access architecture for providing data services to applications, thereby bridging the gap between application data and data as persisted in databases. The update pipeline has the ability to translate changes made to object instances into data store change constructs, and carry those changes over to a data store. Such a pipeline can also advantageously perform the reverse operation, allowing applications to query using the database update pipeline, and receive materialized object instances.

Cooperative caching in mobile ad hoc networks based on data utility

Abstract: Cooperative caching, which allows sharing and coordination of cached data among clients, is a potential technique to improve the data access performance and availability in mobile ad hoc networks. However, variable data sizes, frequent data updates, limited client resources, insufficient wireless bandwidth and client's mobility make cache management a challenge. In this paper, we propose a utility based cache replacement policy, least utility value (LUV), to improve the data availability and reduce the local cache miss ratio. LUV considers several factors that affect cache performance, namely access probability, distance between the requester and data source/cache, coherency and data size. A cooperative cache management strategy, Zone Cooperative (ZC), is developed that employs LUV as replacement policy. In ZC one-hop neighbors of a client form a cooperation zone since the cost for communication with them is low both in terms of energy consumption and message exchange. Simulation experiments have been conducted to evaluate the performance of LUV based ZC caching strategy. The simulation results show that, LUV replacement policy substantially outperforms the LRU policy.

Method and system for providing remote access to resources in a secure data center over a network

Abstract: Methods, computer products, and systems are described for providing remote access to resources in a secure data center protected by at least one firewall. One method includes sending by an internal server within the secure data center a request to an external server outside of the secure data center to establish a secure data transport channel between the internal server and the external server. The request travels through at least one firewall protecting the secure data center and over a public network, a private network, and/or a second firewall. The internal server receives a reply to the request from the external server granting the request and confirming the establishment of the secure data transport channel. When a first message from the external server instructing the internal server to create a first data access point associated with a first session is received via the established secure data transport channel, the internal server instantiates the first data access point for the first session and visual data corresponding to the resources in the secure data center is sent from the first data access point to the external server via the secure data transport channel. The visual data is received by the external server and then sent to a first client associated with the first session so that the first client is provided visual access to the resources in the secure data center while the resources remain protected within the secure data center.

Data access patterns in the Amazon.com technology platform

Abstract: The Amazon.com technology platform provides a set of highly advanced business and infrastructure services implemented using ultra-scalable distributed systems technologies. Within this environment we can identify a number of specific data access patterns, each with their own availability, consistency, performance and operational requirements in order to serve a collection of highly diverse business processes. In this presentation we will reviews these different patterns in detail and discuss which technologies are required to support them in an always-on environment.

Combination of Replication and Scheduling in Data Grids

Abstract: Data Grid environment is a geographically distributed that deal with date-intensive application in scientific and enterprise computing. Dealing with large amount of data makes the requirement for efficiency in data access more critical. The goal of replication is to shorten the data access not only for user accesses but enhancing the job execution performance. In this paper, we proposed a new approach to replication based on organizing the data in Data Grid based on its property. In this paper, we organized the data in to several data categories that it belongs to. And this information is used to help improving data replication placement strategy. We study our approach and evaluate it through simulation. The result shows that our algorithm has improved 30% over the current strategies.

Business data access client for online/offline client use

Abstract: Architecture for uninterrupted access to business data by enabling work on rich client machines to be stored in a local business data cache that is always available. A dispatching mechanism executes read/write requests against the local cache transparently to a client application, an automatic synchronization mechanism propagates changes bi-directionally when the client goes online and a live connection with the corresponding backend data source is available. A declarative data access model is employed based on operation stereotyping and grouping that enables client applications to transparently execute create, read, update, delete, query (CRUDQ) and association operations against the local cache as if executed against the actual business data source. The architecture supports the offline creation of entities and sets of related entities when the entity identifiers are generated by the business data source and offline navigation of entity associations when foreign keys are not present in the related entities.

Web Services in Building Automation: Mapping KNX to oBIX

Abstract: Web services are a key technology for enabling interoperable machine-to-machine interaction over a network. They also lend themselves excellently to the integration of automation and IT systems. This paper discusses oBIX, a new standard for representing and accessing building automation (BA) data via Web services. It is shown how access to a BA system that follows the KNX protocol standard can be faithfully represented by way of oBIX entities. A prototype implementation of such a gateway is presented. The extensible nature of the oBIX data model is leveraged by using it to express the required KNX-oBIX mapping information as well. This approach allows a particularly clear and efficient gateway design.

Bridging the gap: a virtual health record for integrated home care

Abstract: Introduction : The coexistence of different information systems that are unable to communicate is a persistent problem in healthcare and in integrated home care in particular. Theory and methods : Physically federated integration is used for design of the underlying technical architecture to implement a mobile virtual health record for integrated home care. A user centered system development approach is followed during design and development of the system. Results : A technical platform based on a service-oriented approach where database functionality and services are separated has been developed. This guarantees flexibility with regard to changed functional demands and allows third party systems to interact with the platform in a standardized way. A physically federated integration enables point-of-care documentation, integrated presentation of information from different feeder systems, and offline access to data on handheld devices. Feeder systems deliver information in XML-files that are mapped against an ideal XML schema, published as an interface for integration with the information broker, and inserted into the mediator database. Conclusions : A seamless flow of information between both different care professionals involved in integrated home care and patients and relatives is provided through mobile information access and interaction with different feeder systems using the virtual health record.

Decentralized data management framework for data grids

Abstract: A new class of data intensive applications has led to increased demand for cost-efficient resource sharing approaches. Yet, providing efficient access to widely distributed data for large numbers of users poses considerable challenges. Most existing Grid systems are centrally managed, thus hindering their scalable expansion. We introduce a new distributed, adaptive, and scalable middleware that provides transparent access to data in Data Grids. Our approach relies on dynamic techniques that adapt replica creation to continuously changing network connectivity and users' behavior. Results from simulations and deployment of our middleware show that our solution provides better data access performance than static approaches.