Abstract : in order to demonstrate the implementation scheme of the automatic system for telephone trunk , the implementation is discussed from the software and the hardware , and it is proved that the detection efficiency and precision of the system are preferable 文摘:对局间中继线路自动侦测系统的实现方案进行论证，从软件和硬件方面进行探讨，证明该系统有较好的检测效率和检测精度。
Without the central switch a lot of channels and tracks are shared by many users , the cost of the channels is reduced and the utilization factor of them is improved . user can call others by dialing the number , and the dialing is simple and quick 本文给出了有限用户的呼损率公式和有限用户多信道共用系统的信道配置方法，并可根据实际话务量、系统用户数、呼损率配置共用绳路数和中继线对数。
Besides the protection of the modules themselves , dispersion is another factor we should take into account in organizing a network . for instance , the trunk lines of a trunk should be dispersed to different 155 mbits trunk modules and each 155 mbits trunk modules to different physical routes 除了模块本身的保护机制外，在网络的组织上要考虑分散度，如一个局向的中继线要分散在不同的155mbits中继模块，每个155mbs中继模块要分配到不同的物理路由。
For a small local network , the gsn node can be located in the exchange room . the pcu is connected to the sgsn on a ppp basis so as to save trunks . when there are many pcus and they are located in places other than the exchange , they can access to the sgsn via the existing fr network or a self - built fr network 对于规模较小的本地网，可将gsn节点设置在交换机房内，其pcu经过交换机以ppp的方式同sgsn连接，可以节省中继线路。当pcu单元数量多且与交换机位于不同的地方时，可以通过现有的fr网或自己组建fr网络接入到sgsn中，此时gsn节点位置相对灵活。
Typical applications but not limited to , are professional quality video communications ( ip - video ) , remote digital surveillance , video conferencing , corporate access for banks , military , villas , mines , border surveillance , traffic control , switching cabinets , warehouses , equipments , remote education medical , high - speed internet service to commercial customers , ddn extension , internet cafes , and real time remote data backup 促使许多企业用户放弃adsl , t1e1和帧中继线路，转而使用sdsl ，一些t1e1或帧中继业务提供者已经开始将发展重点放在sdsl上。因为sdsl的稳定性、可靠性、安全性均远高于adsl 。造价又远低于t1e1和帧中继线路,越来越多的企业用户开始使用sdsl服务。
Based on the results , beijing telecom has forwarded its suggestions to relevant vendors , who in turn have made a number of improvements in their later product versions . with the stm - 1 link as the inter - office trunk , the number of ddfs will be markedly reduced , thus saving floor space in the pit and wiping off distribution - related failures . besides , the number of outgoing trunks will be brought down , thus demanding less maintenance staff and improving the maintenance efficiency 交换机利用stm - 1链路作为局间中继线路，可以减少数字配线架ddf的数量与规模，从而大大节省局房占用面积，解决局房面积紧张的问题；还可大大减少配线数量，去除因配线引起的故障；另外，交换机利用stm - 1链路作为局间中继线路，可以减少出局中继线路数量，从而可以减少维护人员对中继线路进行维护的工作量，提高维护效率。
