scope:

This standard establishes criteria and procedures for evaluating the Resistance and Impedance performance of analog telephones and terminals. Such equipment may be connected to the Public Switched Telephone Network (PSTN) to provide traditional narrowband (300 to 3300 Hz) wireline telephone service. It may also be connected to Analog Terminal Adapters (ATAs) and Voice Gateways (VGs) that provide packet-based services such as Voice over Internet Protocol (VoIP), some of which are capable of supporting wideband (100 to 7000 Hz) voice transmission.

The dc resistance requirements and many of the ac impedance requirements in this Standard apply equally to equipment in both bandwidth categories. Where appropriate, extended frequency range impedance requirements are specified for equipment intended to be used in wideband applications.

The recommended on-hook requirements are written with a model of five (5) devices attached to the Customer Interface (CI) and the minimum performance requirements are based on a model of three (3) devices.