Christophe Bobineau

Coordinating services for accessing and processing data in dynamic environments

This paper presents an approach and an associated system named Hypatia for accessing and processing data by coordinating services in dynamic environments. A dynamic environment consists of applications, servers and devices that can be static and nomad, and that produce or consume data on demand (e.g., online applications, Web-hosted DBMS) or continuously (messaging systems, mobile services). In such an environment, data are hidden behind services that export application programming interfaces (API) through heterogeneous networks and that provide functions for retrieving and processing data. In order to have an aggregated and integrated view of the dynamic environment at every moment (e.g., accessing Googles agenda service and feeding a Twitter service for continuously locating friends as we all stroll in a city), data consumers have to execute sets of service calls, i.e., subscribe to continuous data producers, aggregate results and feed other services and then obtain results and eventually start over again. No off-the-shelf DBMS provides such service oriented querying approach including continuous, one-shot, mobile and static query evaluation. Our work introduces the notion of hybrid query that declaratively expresses data consumers requirements and an associated query evaluator, Hypatia, that executes data oriented query service coordinations; taking advantage of the services available in the network (data providers and devices computing capacity) and yielding the query result.

Towards a Mediation System Framework for Transparent Access to Largely Distributed Sources The MediaGrid Project

Invited Talks.- Databases and the Grid: JDBC in WSDL, or Something Altogether Different?.- Emergent Semantics Systems.- Integration.- User-Specific Semantic Integration of Heterogeneous Data: The SIRUP Approach.- Towards a Mediation System Framework for Transparent Access to Largely Distributed Sources.- Null Values Revisited in Prospect of Data Integration.- Peer to Peer.- Semantic-Based Query Routing and Heterogeneous Data Integration in Peer-to-Peer Semantic Link Networks.- Peer Selection in Peer-to-Peer Networks with Semantic Topologies.- Autonomous Gossiping: A Self-Organizing Epidemic Algorithm for Selective Information Dissemination in Wireless Mobile Ad-Hoc Networks.- Hyper: A Framework for Peer-to-Peer Data Integration on Grids.- Semantics for Scientific Applications.- Semantically Linking and Browsing Provenance Logs for E-science.- Emergent Semantics: Towards Self-Organizing Scientific Metadata.- Semantic Visualization of Biochemical Databases.- Interoperability and Mediation.- Semantic Information Interoperability in Open Networked Systems.- A New Mechanism for the Interoperability of Data Systems.- An Architecture for Recommendation Based Service Mediation.- Global Services and Schemas.- Static-Dynamic Integration of External Services into Generic Business Processes.- Knowledge Sifter: Agent-Based Ontology-Driven Search over Heterogeneous Databases Using Semantic Web Services.- Managing Grid Schemas Globally.- Posters.- Relational Graphical Models of Computational Workflows for Data Mining.- InfoGrid: Information Resource Integration.- Semantic Annotation of Classification Data for KDD Support Services.- Role of the Ontologies in the Context of Grid Computing and Application for the Human Disease Studies.- Cluster Entries for Semantic Organization of Peer-to-Peer Network.- A Peer-to-Peer Service Supporting Data Quality: Design and Implementation Issues.- Analysis Patterns for the Geographic Database Conceptual Schema: An Ontology Aided Approach.

Towards a Mediation System Framework for Transparent Access to Largely Distributed Sources

This paper presents the MediaGrid project whose goal is the definition of a mediation framework for transparent access to largely distributed sources. Frameworks are reusable pieces of design being expressed as a set of interfaces and components together with the description of their collaboration. Research topics addressed by the MediaGrid project include meta-data design, generation of mediation queries and adaptive and interactive query evaluation.

The QOL approach for optimizing distributed queries without complete knowledge

This paper concerns the integration of the Case Based Reasoning (CBR) paradigm in query processing, providing a way to optimize queries when there is no prior knowledge on queried data sources and certainly no related metadata such as data statistics. Our Query Optimization by Learning (QOL) approach optimizes queries using cases generated from the evaluation of similar past queries. A query case comprises: (i) the query, (ii) the query plan and (iii) the measures (computational resources consumed) of the query plan. The work also concerns the way the CBR process interacts with the query plan generation process. This process uses classical heuristics and makes decisions randomly (e.g. when there is no statistics for join ordering and selection of algorithms, routing protocols); It also (re)uses cases (existing query plans) for similar queries parts, improving the query optimization and evaluation efficiency.

UBIQUEST, for rapid prototyping of networking applications

An UBIQUEST system provides a high level programming abstraction for rapid prototyping of heterogeneous and distributed applications in a dynamic environment. Such a system is perceived as a distributed database and the applications interact through declarative queries including declarative networking programs (e.g. routing) and/or specific data-oriented distributed algorithms (e.g. distributed join). Case-Based Reasoning is used for optimization of distributed queries when as there is no prior knowledge on data (sources) in networking applications, and certainly no related metadata such as data statistics.

A strategy to develop adaptive and interactive query brokers

This paper focuses on the software architecture and components for supporting core adaptive and interactive query processing. The architecture permits the reuse of most of the existing adaptation techniques and facilitates the development of new ones. Developers will use it to program adaptable and interactive query evaluators, called Query Brokers. Three adaptability levels are considered: (i) static adaptability, achieved at query broker building time, (ii) personalization, achieved for each (user) query having specific needs, and (iii) dynamic adaptability, achieved during query evaluation. The paper first proposes to leverage on the large amount of work done on query processing through a set of component interfaces, abstracting functions of brokers. Then, along with these abstractions, it presents our partial implementation of the main components for optimization mechanisms and observation, notification and rule management useful for dynamic adaptation. This partial implementation defines a toolbox facilitating the instantiation phase of a Query Broker development.