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Service choreography is a form of service composition in which the interaction protocol between several partner services is defined from a global perspective.〔S-Cube Knowledge Model: (Service Choreography )〕 The intuition underlying the notion of service choreography can be summarised as follows:
That is, at run-time each participant in a service choreography executes its part of it (i.e. its ''role'') according to the behavior of the other participants.〔 A choreography's role specifies the expected messaging behavior of the participants that will play it in terms of the sequencing and timing of the messages that they can consume and produce.〔 ==Service choreography and service orchestration== Service choreography is better understood through the comparison with another paradigm of service composition: service orchestration. On one hand, in service choreographies the logic of the message-based interactions among the participants are specified from a global perspective. In service orchestration, on the other hand, the logic is specified from the local point of view of one single participant, called the ''orchestrator''. In the service orchestration language BPEL, for example, the specification of the service orchestration (e.g. the BPEL process file) can be deployed on the service infrastructure (for example a BPEL execution engine like Apache ODE). The deployment of the service orchestration specification creates the composed service. In a sense, service choreography and orchestrations are two flips of the same coin. On one hand, the roles of a service choreography can be extracted as service orchestrations through a process called ''projection''.〔 Through projection it is possible to realize ''skeletons'', i.e. incomplete service orchestrations that can be used as baselines to realize the web services that participate to the service choreography. On the other hand, already existing service orchestrations may be composed in service choreographies. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Service choreography」の詳細全文を読む スポンサード リンク
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