介绍了基于PSTN(公共程控交换电话网络)的环保远程监测系统。
Introduces a remote monitoring-measuring system used for environmental protection based upon PSTN (Public Switched Telephone Networks).
建立程控交换电话网络实现电话通信需要大量的设备费、线路费、维护费和工程费等费用，并且需要一定的施工工期。
Instructing the switching network to realize the telephone communication needs much of equipment charges, lines charges, protection charges, project charges and time.
CallForwarding示例显示了访问转寄的特性，该特性一般见于公共交换电话网络，但是它使用了一个SIP网络。
The call forwarding sample demonstrates the call forwarding feature typically seen in public switched telephone networks, but it USES a SIP network.
话音是人与人之间交流的主要方式，从最早出现公共交换电话网络到现在的第三代移动通信，语音通信是其最基本的功能。
As voice communications is the primary media of communication for human being, it plays a very important role from public switched telephone network to the third generation mobile communications.
从市场情况来看，电信业的竞争正在加剧，PSTN（公共交换电话网络）、CATV（有线电视网）、ATM和IP（数据网）都在相互窥视对方的传统市场。
According to the circumstances of the market, the competition of the telecom vocation is intensifying, the operators of PSTN, CATV, ATM and IP networks are peeking at others traditional markets.
虽然这对传统电话网络在理论上也有可能，但交换设备更容易保护。
While this is in theory possible with traditional telephone networks, access to switching equipment is easier to control.
公共交换电话网是成熟的网络之一。
这些应用对传输速率有限的公共交换电话网(PSTN网)和无线网络提出了重大挑战。
The limited transmission rate available on the Public switched telephone network (PSTN) and on wireless networks presents a significant challenge to digital video communications.
PSTN网关是实现IP网络和公用交换电话网（PSTN）互联的设备。
SIP/PSTN gateway is a device which interworks between IP network and PSTN.
PSTN网关是实现IP网络和公用交换电话网（PSTN）互联的设备。
SIP/PSTN gateway is a device which interworks between IP network and PSTN.
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