Service Layer providing cloud services. IaaS is considered a service providing infrastructure along with PaaS offering middleware and SaaS providing applications.

服务层，提供云服务，如IaaS提供基础设施服务，PaaS提供中间件服务，SaaS提供应用服务。

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Therefore, the middleware layer enhances the focus on the core business function of the application.

因此，中间件层更注重考虑应用程序的核心业务功能。

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A tactical way to handle this situation is implementing a throttling capability within the integration middleware layer.

处理这种情况的一种方法就是在集成中间件层实现一个调节功能。

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In hybrid form, a private cloud can include data stored on premise or off, with a private Platform-as-a-Service middleware layer managing application data and enforcing data security.

FORBES: The Data Protection And Security Case For Private Clouds