Gatekeeper constitutes a very important part in IP phone system.
网守是IP电话系统中重要的组成部分。
This paper presents the new services of IP used in power system, including IP net phone, vedio conference system, IP video monitor and client service center based on IP.
介绍了IP新业务在电力系统中的应用，包括IP网络电话、IP视频会议系统、IP图像监控和基于IP的客户服务中心。
We can easily transplant the system into other domains such as faxes encrypting, IP Phone and private data network by changing the interfacing circuit and adding or deleting software modules.
通过适当地修改接口电路和增删软件模块，可以很方便地把所提出的系统方案移植到其它类似的应用领域中，如传真加密、IP电话加密、专用网络的数据加密等。
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