Isdn information technology - telecommunications and information exchange between systems - interface connector and contact assignments for isdn primary rate access connector located at reference points s and t 信息技术.系统间的通信和信息交换.安置在s和t基准点上的综合服务数字网络
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Information technology - telecommunications and information exchange between systems - interface connector and contact assignments for isdn primary rate access connector located at reference points s and t 信息技术.电信和系统间信息交换.位于参照点s和t的isdn一次群速率接入的接口连接器及触电排列