电路交换公用数据网络
circuit switched public data network
分组交换公用数据网
Packet Switched Public Data Network PSPDN
公用数据交换网
Public Switched Data Network PSDN
电路交换数据网
circuit switched data network
电路交换数据网络
CSAcircuit switched data network
电路交换数据传输服务
circuit switch data transmission service
circuit-switched data-transmission service
circait-switched data-transmission service
高速电路交换数据
high speed circuit switched data
HRhigh speed circuit switched data
高速电路交换数据服务
high speed circuit switched data service
高速电路交换数据业务
high speed circuit switched data
数据电路交换设备
data circuit switching equipment
数据电路交换系统
data circuit switching system
data circuit switch system
增强电路交换数据
enhanced circuit switched data
增强型电路交换数据
enhanced circuit-switched data (ECSD
ECSAenhanced circuit switched data
电路交换公共数据网
Circuit-Switched Public Data Network CSPDN
分封交换式公用数据网络
packet switched public data network
公用交换电话网
public switching telephone network
public switched telephone network
PSTN
PSTN:PublicSwitchTelephoneNetwork
公用交换电话网络
public switched telephone networks
public switched telephone network
PSTN