Steven Newhouse

ICENI: An Open Grid Service Architecture Implemented with Jini

The move towards Service Grids, where services are composed to meet the requirements of a user community within constraints specified by the resource provider, present many challenges to service provision and description. To support our research activities in the autonomous composition of services to form a Semantic Service Grid we describe the adoption within ICENI of web services to enable interoperability with the recently proposed Open Grid Services Architecture.

ICENI: optimisation of component applications within a Grid environment

Effective exploitation of Computational Grids can only be achieved when applications are fully integrated with the Grid middleware and the underlying computational resources. Fundamental to this exploitation is information. Information about the structure and behaviour of the application, the capability of the computational and networking resources, and the availability and access to these resources by an individual, a group or an organisation.In this paper we describe Imperial College e-Science Networked Infrastructure (ICENI), a Grid middleware framework developed within the London e-Science Centre. ICENI is a platform-independent framework that uses open and extensible XML derived protocols, within a framework built using Java and Jini, to explore effective application execution upon distributed federated resources. We match a high-level application specification, defined as a network of components, to an optimal combination of the currently available component implementations within our Grid environment, by using composite performance models. We demonstrate the effectiveness of this architecture through the high-level specification and solution of a set of linear equations by automatic and selection of optimal resources and implementations.

Implementations of a Service-Oriented Architecture on top of Jini, JXTA and OGSI

This paper presents the design of an implementation-independent, Service-Oriented Architecture (SOA), which is the main basis of the ICENI Grid middleware. Three implementations of this architecture have been provided on top of Jini, JXTA and the Open Grid Services Infrastructure (OGSI). The main goal of this paper is to discuss these different implementations and provide an analysis of their advantages and disadvantages.

Meaning and Behaviour in Grid Oriented Components

The ICENI middleware utilises information captured within a component based application in order to facilitate Grid-based scheduling. We describe a system of application related meta-data that features a separation of concerns between meaning, behaviour and implementation, which allows for both communication and implementation selection at run-time, while providing the user with a flow-based programming model. It is shown that this separation enables a flexible approach to scheduling, and eases the integration of components with disparate control flow patterns or data types, by means of converters and tees for collective communication. By explicitly recording application information and supporting multiple scheduling approaches, communication protocols and component applications, while retaining OGSA compatibility, the ICENI component model is ideally suited to Grid computing.

Optimisation of component-based applications within a grid environment

Effective exploitation of computational grids can only be achieved when applications are fully integrated with the grid middleware and the underlying computational resources. Fundamental to this exploitation is information. Information about the structure and behaviour of the application, the capability of the computational and networking resources, and the availability and access to these resources by an individual, a group or an organisation.This paper describes an integrated grid environment that is open, extensible and platform independent. We match a high-level application specification, defined as a network of components, to an optimal combination of the currently available component implementations within our grid environment. We demonstrate the effectiveness of this architecture through high-level specification and solution of a set of linear equations by automatic and optimal resource and implementation selection.

Autonomic service adaptation in ICENI using ontological annotation

With the advent of Web services standards and service-oriented grid architecture, it is foreseeable that competing as well as complimenting computational services will proliferate. Current efforts in standardising service interface focuses on how one can execute these services in terms of their syntactic descriptions. Their capabilities and relations with other service types are only articulated through natural language in the form of documentation. We seek to capture the capability of services by annotating their programmatic interface using the Web ontology language (OWL) [P.F. Patel-Schneider et al., (2003)] in relation to some domain concepts thereby allowing services to be semantically matched based on their ontological annotation. By inferences on this metadata, syntactically different but semantically equivalent service implementations may be autonomously adapted and substituted. We will conclude by applying this independent annotation to Java RMI and WSDL [E. Christensen et al.] service interface to show the autonomic adaptation process over multiple service oriented-architectures. Combining it with familiar high-level programming language, we demonstrate a practical service-oriented programming model.

ICENI: An Integrated Grid Middleware to Support E-Science

Scientists now have a greater desire to undertake work within global collaborations. This increases their dependence on distributed computation, storage and data resources. For this new paradigm of e-research to be easily adopted by the applied science community, it needs to be enabled by a new software infrastructure — Grid middleware. In this chapter, we describe ICENI, an integrated Grid middleware that explores the services and meta-data necessary to support e-research within a variety of application domains. We focus on the services that we feel are necessary to facilitate Grid use, ranging from running a simple self contained application through to building a simulation from scientific software components distributed across a Grid, selecting the optimal combination of services to enact the simulation and paying for them on demand.

Trading Grid services within the UK e-science Grid

The Open Grid Services Architecture (OGSA) presents the Grid community with an opportunity to define standard service interfaces to enable the construction of an interoperable Grid infrastructure. The provision of this infrastructure has, to date, come from the donation of time and effort from the research community primarily for their Own use. The growing involvement of industry and commerce in Grid activity is accelerating the need to find business models that support their participation. It is therefore essential that an economic infrastructure be incorporated into the OGSA to support economic transactions between service providers and their clients. This chapter describes current standardization efforts taking place with the Global Grid Forum and the implementation of such an architecture within the UK e-Science Programme through the Computational Markets project.

An Integrated Grid Environment for Component Applications

Computational grids present many obstacles to their effective exploitation by non-trivial applications. We present a grid middleware, implemented using Java and Jini, that eliminates these obstacles through the intelligent use of meta-data relating to the structure, behaviour and performance of an application. We demonstrate how different problem sizes and selection criteria (minimum execution time or minimum cost) utilise different implementations for the optimal solution of a set of linear equations.

Building Computational Communities from Federated Resources

We describe the design and the implementation in Java and Jini of a Computational Community, which supports the federation of resources from different organisations. Resources from the local Administrative Domain are published in a Jini space to form a Computational Community. Different access control policies can be applied to the same resource in different Computational Communities. We show how this architecture can be extended through the addition of an Application Mapper and Resource Broker to build a computational economy.