WS-CAF: Contexts, Coordination and Transactions for Web Services

Abstract

As Web services have evolved as a means to integrate processes and applications at an inter-enterprise level, traditional transaction semantics and protocols have proven to be inappropriate. Web services-based transactions, colloquially termed Business Transactions, differ from traditional transactions in that they execute over long periods, they require commitments to the transaction to be “negotiated” at runtime, and isolation levels have to be relaxed. A solution to this problem has to work over HTTP and include existing transaction processing technologies of all types: database management systems, application servers, message queuing systems and packaged applications. In this paper we’ll look at the WS-CAF standardization effort and show how it is attempting to address this important and difficult subject. We’ll also consider how the architecture defined by WS-CAF fits into the evolving architecture of Web services.