说明：  此文档为T.30建议书 本建议书规定了ITU-T T.4建议书定义的三类传真终端使用的规程。这些规程可以在公用 电话交换网、国际租用电路和综合业务数字网（ISDN）上传送文件。进一步，这些规程允许 人工或自动方式通信，并可以要求文件传输会话交替进行。
(This document recommends books for the T.30 Recommendation provides ITU-T T.4 Recommendation defines three types of end-use of fax protocols. These protocols can be public switched telephone network, international leased circuits and integrated services digital network (ISDN) on the transmission of documents. Further, these procedures allow manual or automatic mode communications, and may require alternate file transfer session.)