Author:
Juha Puustjärvi
Affiliation:
Lappeenranta University of Technology, Finland
Keyword(s):
Composed web services, Advanced transaction models, Semantic atomicity.
Related
Ontology
Subjects/Areas/Topics:
Internet Technology
;
Web Information Systems and Technologies
;
Web Services and Web Engineering
Abstract:
Many transaction models have been developed for modelling composed web services. In these models subtransactions (single web services) can commit and release their resources before the whole composed transaction commits. If the whole transaction aborts, then the (semantic) atomicity is ensured by executing compensating transactions which semantically undo the effects of the committed subtransactions. However, using compensating transactions in ensuring semantic atomicity is turned out to be problematic in many cases. In order to avoid these problems we have developed a new transaction model, called CWS-transaction model, for composed web services. It deviates from other advanced transaction models in that it is not based on compensating transactions, but rather it divides the traditional business transaction into two successive transactions, called request transaction and decision transaction. The commitment of the request transaction ensures that the decision transaction will not fa
il, and so the atomicity of the CWS-transaction is ensured. In this paper we specify the components of the CWS-transaction model, their execution dependencies, the correctness criteria of the CWS-transactions and give an example of the implementation of the CWS-transaction model.
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