The Quality of Service attributes of a software component heavily depend on its environment. For example, if a component uses a highly unreliable service, its own reliability is likely to decrease as well. This relation can be described with parametric contracts, which model the dependence between provided and required services of a component. Until now, parametric contracts can only model sing...

The paper represents current achievements of an ongoing research that aims to develop a formal approach supporting an automatic selection of a Web service sought by a requestor. The approach is based on the matching the requestor’s requirements for a ”useful” service against the service description offered by the provider. We focus on the checking behavioral compatibility between operation cont...

The relationships between the loosely coupled services of a composition can be non-deterministic and unreliable. This requires that a composite application have the ability to adaptively reconfigure itself to continuously satisfy the system requirements. Imperative composition approaches, such as BPEL, do not provide the abstractions necessary to create adaptive compositions. In this paper we i...

Design by contract is a well-established paradigm in software engineering. Bertrand Meyer first introduced the rigorous distinction between the responsibilities of service provider and service consumer for fine grain software artifacts (classes). This paper considers service contracts in the context of service-oriented architecture for complex enterprise information infrastructures. Identifying...

I this paper, we analyze the contracting issues that arise in collaborative services, such as consulting, financial planning, and information technology outsourcing. In particular, we investigate how the choice of contract type—among fixed-fee, time-and-materials, and performance-based contracts—is driven by the service environment characteristics. We find that fixed-fee contracts contingent on...

This paper reports on the use of coordination contracts, presented at the previous two IWPSE workshops, in a project for a credit recovery company. We have designed and implemented a framework that allows users to define several business rules according to pre-defined parameters. However, some rules require changes to the services provided by the system. For these, we use coordination contracts...