ETSI EN 300 267-1-1998 综合业务数字网(ISDN).7khz电话,可视电话,声像会议和视频会议电信业务.1号数字用户信令系统(DSS1)协议.第1部分:协议规范(版本1.2.2) ?
Integrated Services Digital Network (ISDN); Telephony 7 kHz, Videotelephony, Audiographic Conference and Videoconference Teleservices; Digital Subscriber Signalling System No. One (DSS1) Protocol; Part 1: Protocol Specification Version 1.2.2