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8 CONCLUSIONS
This paper presented an infrastructure to define,
execute and monitor WS-contracts. In the proposed
approach, a WS-contract comprises collaborative
partners, business process specified in AO4BPEL
and QoS attributes of services defined with WS-
Agreement. AO technology is used to separate
concerns such as monitoring into aspects. Those
aspects are executed when defined join point are
reached in the process. Compared to other
approaches, the proposed solution requires no
instrumentation, uses Web services standards and
provides an integrated infrastructure for dealing with
contract establishment and monitoring.
Future work includes: i) studying and
incorporating other AO properties to enrich the
proposed approach; ii) concluding the development
of the WS-Contract Monitor structure, from the
BPM execution environment; and, iii) carrying out a
broader experiment of the presented proposal to
evaluate its benefits and its limitations.
ACKNOWLEDGEMENTS
This work was supported by The State of São Paulo
Research Foundation (FAPESP) and The National
Council for Scientific and Technological
Development (CNPq), Brazil.
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