Optimistic fair contract signing for Web services

Reliable and atomic transactions are a key to successful e-Business interactions. Reliable messaging subsystems, such as IBM's MQ Series, or broker-based techniques have been traditionally used for this purpose. In this paper, we take a radically different approach to address this problem, which is to apply the idea of Optimistic Fair Contract Signing recently proposed by Asokan, Shoup, and Waidner. We show a design of the protocol based on the latest XML and Web Services Security standards and discuss the benefits and limitations of this approach.