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.
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。