SHTM: A Semantic Hierarchy Transaction Model for Web Services Transactions

Web Services (WS) have quickly evolved as an approach to integrate processes and applications at an inter-enterprise level. Such WS-based integrated applications should guarantee consistent data manipulation. Thus, WS should be extended to equip with transaction processing functionalities, i.e. WS transactions. WS transactions differ from traditional transactions in that they execute over long periods and cross multiple loosely-coupled organizations, so traditional transaction models and processing mechanism have been inappropriate for them. In this paper, we first propose a semantic hierarchy transaction model (called SHTM) for WS transactions. On the basis of this, the isolation property of WS transactions is relaxed by allowing uncommitted transactions to lend their data to other executing transaction. Further, we give the commit processing mechanism which can guarantee consistent data manipulation and correct outcomes of WS transactions.