Network to Customer Installation Interfaces - Analog Voicegrade Switched Access Lines with Calling Number Delivery, Calling Name Delivery, or Visual Message-Waiting Indicator Features
This standard provides the signaling and data transmission requirements associated with the following supplemental features that utilize network-originated on-hook data transmission on analog voicegrade switched access lines that use loop-start signaling:- Calling Number Delivery (CND);- Calling Name Delivery (CNAM);- Visual Message-Waiting Indicator (VMWI).The use of the CND, CNAM, or VMWI supplemental features with Integrated Services Digital Network (ISDN) access lines is beyond the scope of this standard.This standard is intended to be used in conjunction with American National Standard for Telecommunica¬tions - Interface between carriers and customer installations - Analog voicegrade switched access lines using loop-start and ground-start signaling, ANSI T1.401-1993. The on-hook data transmission features described in this standard may not be available on access lines that utilize ground-start signaling.The supplemental features provide information about the calling access line to the called access line or information about a message that is waiting to be retrieved. Customer installation equipment that receives the information associated with these services can normally display, print, or store the information, how¬ever, such capabilities are outside of the scope of this standard.Requirements in this standard are specified at the interface between telecommunications carriers, and customer premises cabling and equipment. In this standard, the telecommunications carrier network is referred to as the network and customer premises cabling and equipment is referred to as the customer installation (Cl). The interface between the network and the Cl is referred to as the Network Interface (Nl).The signals that the network presents at the Nl are basically of two types: normal telecommunications system voltages and currents, and voltages and currents due to maintenance activities. The normal sig¬nals are specified in this standard. Abnormal voltages and currents that are the result of the environment (e.g., induced voltages and currents or lightning) are not covered in this standard.Tariffs, contracts, or regulatory acts in various jurisdictions may contain additional or more stringent re¬quirements than those in this standard.