This layer differs from PaaS in that the virtual hardware is provided without a software stack.

这一层与PaaS的不同之处在于，只提供虚拟硬件，而没有软件栈。

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Figure 1 shows that the virtualization component is provided by a layer of software called a hypervisor (sometimes called a virtual machine monitor [VMM]).

图1中所示的这个虚拟化组件是由一个名为hypervisor(有时也叫作虚拟机监视器[VMM])的软件层提供的。

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Support SOA, promote code reuse, enhance programming productivity, and contribute to a more flexible software environment with the virtual data access services layer.

使用虚拟数据访问服务层支持SOA、促进代码重用、提高编程效率和促成更灵活的软件环境。

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