Given the numerous, potentially reusable, Web services available on the Internet, search and composition techniques that efficiently discover viable services will be a strong requirement. A major challenge for dynamic Web service composition will be the ability to measure the quality or reliability of services that are delivered. In this paper, we present a solution for dynamic Web service comp...

Recently many enterprises are adopting web services as the standard between heterogeneous software in the XML message based distributed environment to carry out businesses from B2C to B2B. For effective application of web services, differentiated service quality must be guaranteed. However, majority of the current web services do not differentiate quality of messages and the current web servers...

In this position paper we propose a framework for proactive SLA negotiation that integrates this process with dynamic service discovery and, hence, can provide integrated runtime support for both these key activities which are necessary in order to achieve the runtime operation of service based systems with minimised interruptions. More specifically, our framework discovers candidate constituen...

The process of decision making regarding the outsourcing of various tasks in an enterprise’s value chain involves consideration of a number of important economic trade offs. Outsourcing decisions in the past have typically been of a strategic nature involving long-term commitment. However, given the emerging technologies of Web services and the growing variety of service providers it seems feas...

In this paper we examine contracts to coordinate the capacity decision of a vendor who has been hired by a client to provide call center support. We consider a variety of contracts, all based on our observations of contracts used by one large vendor. We examine the role of different contract features such as pay-per-time, pay-per-call, service level agreements, and constraints on service rates ...

Despite promising high value for electronic business, Service Level Agreements have not yet found major uptake in the business world. A major obstacle to adoption is the lack of adequate tools that facilitate and automate SLA establishment on both the consumer as well as the provider side. In this paper, we describe a generic framework for negotiating SLAs that has been designed and implemented...

Service level agreements (SLAs) establish the terms in which a logistics service may be provided or consumed. During the last years we have been studying techniques to perform an automated analysis of expressive and realistic SLAs, which makes the agreement creation process easier for involved parties. Firstly, we extended WS-Agreement speci cation to allow to apply any type of validity periods...

  Network and processing overhead associated with web services is a significant challenge to its performance. As a result, web service providers often announce a service level agreement. This ensures that consumers, who pay for the service, can get the service at a given quality level. In this paper, we study the competition between two providers offering functionally the same web services, whe...