GRIDCC: Real-time workflow system

The Grid is a concept which allows the sharing of resources between distributed communities, allowing each to progress towards potentially different goals. As adoption of the Grid increases so are the activities that people wish to conduct through it. The GRIDCC project is a European Union funded project addressing the issues of integrating instruments into the Grid. This increases the requirement of workflows and Quality of Service upon these workflows as many of these instruments have real-time requirements. In this paper we present the workflow management service within the GRIDCC project which is tasked with optimising the workflows and ensuring that they meet the pre-defined QoS requirements specified upon them

Contextualized B2B Registries

Abstract. Service discovery is a fundamental concept underpinning the move towards dynamic service-oriented business partnerships. The business process for integrating service discovery and underlying registry technologies into business relationships, procurement and project management functions has not been examined and hence existing Web Service registries lack capabilities required by business today. In this paper we present a novel contextualized B2B registry that supports dynamic registration and discovery of resources within management contexts to ensure that the search space is constrained to the scope of authorized and legitimate resources only. We describe how the registry has been deployed in three case studies from important economic sectors (aerospace, automotive, pharmaceutical) showing how contextualized discovery can support distributed product development processes

IVOA Recommendation: Simple Spectral Access Protocol Version 1.1

The Simple Spectral Access (SSA) Protocol (SSAP) defines a uniform interface to remotely discover and access one dimensional spectra. SSA is a member of an integrated family of data access interfaces altogether comprising the Data Access Layer (DAL) of the IVOA. SSA is based on a more general data model capable of describing most tabular spectrophotometric data, including time series and spectral energy distributions (SEDs) as well as 1-D spectra; however the scope of the SSA interface as specified in this document is limited to simple 1-D spectra, including simple aggregations of 1-D spectra. The form of the SSA interface is simple: clients first query the global resource registry to find services of interest and then issue a data discovery query to selected services to determine what relevant data is available from each service; the candidate datasets available are described uniformly in a VOTable format document which is returned in response to the query. Finally, the client may retrieve selected datasets for analysis. Spectrum datasets returned by an SSA spectrum service may be either precomputed, archival datasets, or they may be virtual data which is computed on the fly to respond to a client request. Spectrum datasets may conform to a standard data model defined by SSA, or may be native spectra with custom project-defined content. Spectra may be returned in any of a number of standard data formats. Spectral data is generally stored externally to the VO in a format specific to each spectral data collection; currently there is no standard way to represent astronomical spectra, and virtually every project does it differently. Hence spectra may be actively mediated to the standard SSA-defined data model at access time by the service, so that client analysis programs do not have to be familiar with the idiosyncratic details of each data collection to be accessed

A Taxonomy of Workflow Management Systems for Grid Computing

With the advent of Grid and application technologies, scientists and engineers are building more and more complex applications to manage and process large data sets, and execute scientific experiments on distributed resources. Such application scenarios require means for composing and executing complex workflows. Therefore, many efforts have been made towards the development of workflow management systems for Grid computing. In this paper, we propose a taxonomy that characterizes and classifies various approaches for building and executing workflows on Grids. We also survey several representative Grid workflow systems developed by various projects world-wide to demonstrate the comprehensiveness of the taxonomy. The taxonomy not only highlights the design and engineering similarities and differences of state-of-the-art in Grid workflow systems, but also identifies the areas that need further research.Comment: 29 pages, 15 figure

Research and development of accounting system in grid environment

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.The Grid has been recognised as the next-generation distributed computing paradigm by seamlessly integrating heterogeneous resources across administrative domains as a single virtual system. There are an increasing number of scientific and business projects that employ Grid computing technologies for large-scale resource sharing and collaborations. Early adoptions of Grid computing technologies have custom middleware implemented to bridge gaps between heterogeneous computing backbones. These custom solutions form the basis to the emerging Open Grid Service Architecture (OGSA), which aims at addressing common concerns of Grid systems by defining a set of interoperable and reusable Grid services. One of common concerns as defined in OGSA is the Grid accounting service. The main objective of the Grid accounting service is to ensure resources to be shared within a Grid environment in an accountable manner by metering and logging accurate resource usage information. This thesis discusses the origins and fundamentals of Grid computing and accounting service in the context of OGSA profile. A prototype was developed and evaluated based on OGSA accounting-related standards enabling sharing accounting data in a multi-Grid environment, the World-wide Large Hadron Collider Grid (WLCG). Based on this prototype and lessons learned, a generic middleware solution was also implemented as a toolkit that eases migration of existing accounting system to be standard compatible.Engineering and Physical Sciences Research Council (EPSRC), Stanford Universit

Proof-of-Concept Application - Annual Report Year 1

In this document the Cat-COVITE Application for use in the CATNETS Project is introduced and motivated. Furthermore an introduction to the catallactic middleware and Web Services Agreement (WS-Agreement) concepts is given as a basis for the future work. Requirements for the application of Cat-COVITE with in catallactic systems are analysed. Finally the integration of the Cat-COVITE application and the catallactic middleware is described. --Grid Computing

Katalog metapodataka u prostornim informacijskim sustavima

This paper gives the short review of the Open Geospatial Consortium (OGC) metadata catalogue services that have the key role in geospatial resource discovery in Spatial Data Infrastructures (SDI). The notion of Spatial Data Infrastructure comprises a collection of technologies, policies and institutional agreements that provide an easier access to geospatial data. The SDI is suitable for usage in geospatial data discovery, evaluation, and also various applications within government, commercial and non-profit sectors, academic institutions, etc. Metadata catalogue services have been specified in OGC Catalogue Service Implementation Specification. The part of the specification that specifies a web interface that supports the storage, retrieval, and management of data related to web services, is called Catalogue Service for the Web (CSW). Metadata catalogues are service brokers that represent a key component in a service-oriented architecture that manages shared resources and facilitates the discovery of resources within an open, distributed system. OGC services have gained significant popularity in recent years and the number of organizations using them has increased. However, the full potential of metadata catalogues has not yet been reached, not only because of the lack of appropriate documentation of data in the form of standardized metadata, but because the lack of semantics of the data. The analysis of the usage of metadata catalogue services in geodetic information systems has been given and the proposal for a possible solution for improvement has been made.U radu je prikazan kratki pregled usluga kataloga metapodataka Otvorenoga geoprostornog konzorcija (OGC) koji ima ključnu ulogu u otkrivanju geoprostornih izvora informacija u Prostornoj infrastrukturi podataka (SDI). Pojam Prostorne infrastrukture podataka obuhvaća skup tehnologija, strategija i institucionalnih sporazuma koji osiguravaju lakši pristup geoprostornim podacima. SDI je pogodan za upotrebu pri otkrivanju geoprostornih podataka, evaluaciji, kao i različitim primjenama unutar vladinog, komercijalnog i neprofitabilnog sektora, akademskih institucija, itd. Usluge kataloga metapodataka specificirane su u OGC Specifikaciji ostvarivanja usluga kataloga. Dio specifikacije koji se odnosi na web-sučelje koje podržava pohranu, učitavanje i upravljanje podacima koji se odnose na web-servise naziva se Kataloški servis za web (CSW). Katalozi metapodataka su agenti za usluge koji predstavljaju ključnu komponentu u arhitekturi namijenjenoj uslugama, a koja upravlja zajedničkim izvorima i olakšava otkrivanje izvora unutar otvorenoga distribuiranog sustava. OGC usluge stekle su značajnu popularnost u proteklim godinama, a broj organizacija koje ih koriste se povećao. Međutim, puni potencijal kataloga metapodataka još nije dostignut, ne samo zbog nedostatka odgovarajuće dokumentacije podataka u obliku standardiziranih metapodataka, već i zbog nedostatka semantike podataka. Napravljena je analiza korištenja usluga kataloga metapodataka u geodetskim informacijskim sustavima te je dan prijedlog za moguća rješenja u svrhu poboljšanja