定义电话网络和客户场所设备之间的通信接口标准。客户场所的设备被识别为遥测接口单元（TIU），可以在网络和客户场所的设备之间提供接口，例如公用电仪表、报警设备、控制开关和其他待确定的设备。

Define a standard for the communications interface between the telephone network and the device at the customer premise. The device at the customer premise is identified as a Telemetry Interface Unit (TIU) and may provide an interface between the network and devices at the customer premise such as utility meters, alarm devices, control switches and other devices to be determined.