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介绍铁路通信网的一种新型用户交换机哈尔滨铁路局金纯孝目前铁路的通信能力还很薄弱，很多地区自动电话交换机容量和用户电缆严重不足，很难适应运输生产发展需要。在地区通信网的终端发展用户交换机是一种投资少、见效快的有效办法。采用哪种交换机、选取什么样的联网方...
Introducing a new type of user exchange in railway communication network Jin Railway Railway Bureau of Jin Chunxiao current railway communication capacity is still very weak, many areas of automatic telephone exchange capacity and user cable serious shortage of it is difficult to adapt to the needs of transport and production development. The development of a PBX in a regional communications network terminal is an effective way to invest less and get results fast. What kind of switch, choose what kind of networking side ...