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- all electronic digital telephone switching system 全电子数字电话交换系统
- digital telephone switching system 数字电话交换局
- digital telephone switching service 数字电话交换业务
- digital telephone switch 数字电话转换器
- Analysis of Connecting Quality Index of Digital Telephone Switching Network 数字电话网的接续质量指标分析
- Code for construction of railway SPC digital telephone switching engineering 铁路数字程控交换通信工程施工规范
- A. B. Strowger invents the telephone switch, dial telephone. 史端乔发明自动电话交换系统。
- Regulation for design of railway digital telephone switching communication system 铁路程控数字交换通信工程设计规定
- Standard for quality inspection and assessment of railway digital telephone switching engineering 铁路数字程控交换通信工程质量评定验收标准
- 7 recommended by CCITT has been widely used in the digital telephone switching network and in the coming ISDN because of its high efficiency, flexibility and versatility. 7公共信道信令系统(CCSS),由于它的高效率、灵活性和多用性,已广泛地用于数字电话交换网和即将到来的综合业务数字网(ISDN)中。
- ICV systems which link computers and digital telephone lines are becoming popular because they are relatively inexpensive yet effective. ICV系统可以把电脑和数字电话线连起来，相对而言由于这个系统物美价廉，因而普及较快。
- Western panel type automatic telephone switch board 西部板式自动电话交换机
- If not,the call went to the company's in-house telephone switching system,or PBX (private branch exchange). 如果没有，电话就转到公司内的电话交换系统（即PBX，用户电话交换机）。
- SSPs are telephone switches,interconnected by SS7 links,that originate,terminate or tandem calls. SSP 是由 SS7 链路互连的电话交换机，用来发起、终止或汇接呼叫。
- crossbar type automatic telephone switch board 纵横制自动电话交换机
- An IP PBX is telephone switching equipment that resides in a private business instead of the telephone company. IP PBX是私人公司中的电话交换设备,而不是电话公司中的电话交换设备。
- SS7 is a switch-to-switch protocol that lets telephone switches set up calls, manage circuits and perform intelligent network functions. 七号信令系统（SS7）是交换机至交换机的协议，它让电话交换建立通话、管理电路和执行智能网络功能。
- SSPs are telephone switches, interconnected by SS7 links, that originate, terminate or tandem calls. SSP 是由 SS7 链路互连的电话交换机，用来发起、终止或汇接呼叫。
- D.Talley, "Basic Telephone Switching Systems", Hayden Book Company, Rochelle Park, N.J. 1969. 由坐标式交换器所组成的交换网路。
- If not, the call went to the company's in-house telephone switching system, or PBX (private branch exchange). 如果没有，电话就转到公司内的电话交换系统（即pbx，用户电话交换机）。
