Called subscriber identification . optional signal used to provide the specific identity of the called subscriber by its international telephone number 拨入用户识别。通过唯一的手机号码来识别拨入用户的可选信号。
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Calling subscriber identification . optional signal indicates that the following frame is an identification of the calling station . used to provide additional security to fax procedure 通话用户识别。可选信号标识后续的一些帧用来标识呼叫位置。传真过程通常使用附加的安全措施。
