Three Decision-making Mechanisms to facilitate Negotiation of Service Level Agreements for Web Service Compositions

The negotiation of Service Level Agreements for composite web services is a very complex process. It involves the coordination of the negotiation process so that the end-to-end QoS requirements of the user request are satisfied while ensuring that the atomic QoS requirements are also simultaneously satisfied. This paper summarizes three decision-making mechanisms which support the process of Service Level Agreement negotiation for composite web services. The mechanisms include: the decomposition of the overall user preferences into the preferences of individual negotiation agents representing each atomic services within the composition; the selection of the prospective negotiation partners for the actual interaction from a list of potential service providers and finally the negotiation of Service Level Agreement with the selected provider agents while ensuring that the end-to-end QoS is satisfied

A Conceptual Model for Negotiating in Service-Oriented Environments

Web services have been developed in recent years as a fundamental technique for the new generation of B2B or EAI applications. For their getting more available that imposes a new vision of service-oriented computing, the software industry has shifted its attention on software from developing a product as required to delivering a service on demand. In order to gain the many benefits from such a service-oriented model of software, several critical issues need to be addressed in a service-oriented environment such as differentiation of services with multiple attributes, dynamic selection and provision of services in a supply chain style, and commitment of services with prescribed rules. From the perspective of management, these issues are concerned within a process of negotiating desired services in a service-oriented environment. In this paper, we propose an object-oriented model that specifies such a negotiation process with explicit constructs addressing these critical issues. The model contains an architecture diagram that describes required components and their interactions for fulfilling the negotiation process, as well as a class/sequence diagram that specifies in detail what class objects these components have in order to collaboratively support all required behaviors occurred within the negotiation process

Semantic web service choreography: contracting and enactment

Abstract. The emerging paradigm of service-oriented computing requires novel techniques for various service-related tasks. Along with automated support for service discovery, selection, negotiation, and composition, support for automated service contracting and enactment is crucial for any large scale service environment, where large numbers of clients and service providers interact. Many problems in this area involve reasoning, and a number of logic-based methods to handle these problems have emerged in the field of Semantic Web Services. In this paper, we build upon our previous work where we used Concurrent Transaction Logic (CTR) to model and reason about service contracts. We significantly extend the modeling power of the previous work by allowing iterative processes in the specification of service contracts, and we extend the proof theory of CTR to enable reasoning about such contracts. With this extension, our logic-based approach is capable of modeling general services represented using languages such as WS-BPEL

Library Resources: Procurement, Innovation and Exploitation in a Digital World

The possibilities of the digital future require new models for procurement, innovation and exploitation. Emma Crowley and Chris Spencer describe the skills staff need to deliver resources in hybrid and digital environments. The chapter demonstrates the innovative ways that librarians use to procure and exploit the wealth of resources available in a digital world. They also describe the technological developments that can be adopted to improve workflow processes and they highlight the challenges faced on this fascinating journey