本标准规定了当在接口上使用E&M信令时，电信运营商和客户装置之间的模拟语音级接口的信令要求。这些要求旨在帮助电信网络所用产品的运营商、制造商和用户了解现有网络的参数。本标准是T1的修订版。409-1996，全部替换。

This standard provides signaling requirements for the analog voicegrade interface between telecommunication carriers and customer installations when E&M signaling is used across the interface. These requirements are intended to assist carriers, manufacturers, and users of products to be used with telecommunication networks to understand the parameters of the existing networks. This standard is a revision of T1.409-1996, which is replaced in its entirety.