NI1

Abbreviation for National ISDN 1. NI1 is a specification for a standard ISDN line. The goal is for National ISDN 1 to become a set of standards which every manufacturer can conform to. For example, ISDN devices that conform to the National ISDN 1 standard will work, regardless of the central office the customer is connected to. Future standards, denoted as NI2 and NI3, are currently being developed.