The front end is composed of a client computer, or the computer network of an enterprise, and the applications used to access the cloud.

前端由客户机计算机（或企业的计算机网络）和用来访问云的应用程序组成。

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Each controller can be regarded as a front-end connecting with the monitoring network. The controllers can be operated by high-level computer, or run separately out of the net.

各控制器均可看作挂接在监控网络上的一个前端，可通过上位机进行操作，也可脱网运行。

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