39,918 research outputs found
A framework to coordinate web services in composition scenarios
This paper looks into the coordination of web services following their acceptance to participate in a composition scenario. We identify two types of behaviours associated with component web services: Operational and control behaviours. These behaviours are used to specify composite web services that are built upon component web services. In term of orchestration a composite web service could be either centralised or peer-to-peer. To support component/composite web services coordination per type of orchestration schema, various types of messages are exchanged between these web services. Experiments showing the use of these messages are reported in this paper as well. Copyright © 2010 Inderscience Enterprises Ltd
A Methodology for Engineering Collaborative and ad-hoc Mobile Applications using SyD Middleware
Today’s web applications are more collaborative and utilize standard and ubiquitous Internet protocols. We have earlier developed System on Mobile Devices (SyD) middleware to rapidly develop and deploy collaborative applications over heterogeneous and possibly mobile devices hosting web objects. In this paper, we present the software engineering methodology for developing SyD-enabled web applications and illustrate it through a case study on two representative applications: (i) a calendar of meeting application, which is a collaborative application and (ii) a travel application which is an ad-hoc collaborative application. SyD-enabled web objects allow us to create a collaborative application rapidly with limited coding effort. In this case study, the modular software architecture allowed us to hide the inherent heterogeneity among devices, data stores, and networks by presenting a uniform and persistent object view of mobile objects interacting through XML/SOAP requests and responses. The performance results we obtained show that the application scales well as we increase the group size and adapts well within the constraints of mobile devices
Resource Oriented Modelling: Describing Restful Web Services Using Collaboration Diagrams
The popularity of Resource Oriented and RESTful Web Services is increasing rapidly. In these, resources are key actors in the interfaces, in contrast to other approaches where services, messages or objects are. This distinctive feature necessitates a new approach for modelling RESTful interfaces providing a more intuitive mapping from model to implementation than could be achieved with non-resource methods. With this objective we propose an approach to describe Resource Oriented and RESTful Web Services based on UML collaboration diagrams. Then use it to model scenarios from several problem domains, arguing that Resource Oriented and RESTful Web Services can be used in systems which go beyond ad-hoc integration. Using the scenarios we demonstrate how the approach is useful for: eliciting domain ontologies; identifying recurring patterns; and capturing static and dynamic aspects of the interface
Inter-organizational fault management: Functional and organizational core aspects of management architectures
Outsourcing -- successful, and sometimes painful -- has become one of the
hottest topics in IT service management discussions over the past decade. IT
services are outsourced to external service provider in order to reduce the
effort required for and overhead of delivering these services within the own
organization. More recently also IT services providers themselves started to
either outsource service parts or to deliver those services in a
non-hierarchical cooperation with other providers. Splitting a service into
several service parts is a non-trivial task as they have to be implemented,
operated, and maintained by different providers. One key aspect of such
inter-organizational cooperation is fault management, because it is crucial to
locate and solve problems, which reduce the quality of service, quickly and
reliably. In this article we present the results of a thorough use case based
requirements analysis for an architecture for inter-organizational fault
management (ioFMA). Furthermore, a concept of the organizational respective
functional model of the ioFMA is given.Comment: International Journal of Computer Networks & Communications (IJCNC
On the Automated Synthesis of Enterprise Integration Patterns to Adapt Choreography-based Distributed Systems
The Future Internet is becoming a reality, providing a large-scale computing
environments where a virtually infinite number of available services can be
composed so to fit users' needs. Modern service-oriented applications will be
more and more often built by reusing and assembling distributed services. A key
enabler for this vision is then the ability to automatically compose and
dynamically coordinate software services. Service choreographies are an
emergent Service Engineering (SE) approach to compose together and coordinate
services in a distributed way. When mismatching third-party services are to be
composed, obtaining the distributed coordination and adaptation logic required
to suitably realize a choreography is a non-trivial and error prone task.
Automatic support is then needed. In this direction, this paper leverages
previous work on the automatic synthesis of choreography-based systems, and
describes our preliminary steps towards exploiting Enterprise Integration
Patterns to deal with a form of choreography adaptation.Comment: In Proceedings FOCLASA 2015, arXiv:1512.0694
Proof-of-Concept Application - Annual Report Year 2
This document first gives an introduction to Application Layer Networks and subsequently presents the catallactic resource allocation model and its integration into the middleware architecture of the developed prototype. Furthermore use cases for employed service models in such scenarios are presented as general application scenarios as well as two very detailed cases: Query services and Data Mining services. This work concludes by describing the middleware implementation and evaluation as well as future work in this area. --Grid Computing
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