即使它们允许存在多个物理分布的服务实例，但是每个实例都只有一个抽象定义(由组织统一管理)和一个公共实现。
Even if they allow multiple physically distributed instances of services, there is one abstract definition for each — managed by the organization as a whole — and a common implementation.
服务层由 SOA中定义的所有服务构成，其中，服务仅仅是对一个或多个与业务一致的 IT功能（操作）的抽象规范。
The services layer consists of all the services defined within the SOA where a service is just an abstract specification of one or more business-aligned IT functions (operations).
注：抽象与实际语义的更严格对应可能由每个实现自行定义。
Note: more stringent correspondences between abstract and actual semantics may be defined by each implementation.
是利用经过良好定义的接口从服务提供者的细节中抽象出来的，这些接口由显式接口以及代理和调用程序对象提供支持。
Ed from service provider details with well-defined interfaces supported by explicit interfaces, and proxy and invoker objects.
是利用经过良好定义的接口从服务提供者的细节中抽象出来的，这些接口由显式接口以及代理和调用程序对象提供支持。
Ed from service provider details with well-defined interfaces supported by explicit interfaces, and proxy and invoker objects.
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