More commonly stands for National ISDN, less commonly for Narrowband ISDN.

Narrow-ISDN (to distinguish it from Broadband ISDN). ISDN by any other name.

Narrowband Integrated Services Digital Network: Services include basic rate interface (2B+D or BRI) and primary rate interface (30B+D - Europe and 23B+D - North America or PRI). Supports narrowband speeds at/or below 1.5 Mbps.

Narrowband ISDN: same as ISDN

Narrowband Integrated Services Digital Network. Standards-based voice and data network that operate over today's TDM-based switches and provides 144K and 1.544 Mbps interfaces.

Narrowband ISDN. Communication standards developed by the ITU-T for baseband networks. Based on 64-kbps B channels and 16- or 64-kbps D channels. Contrast with BISDN. See also BRI, ISDN, and PRI.

A network architecture and set of standards introduced in 1983 for an all-digital network. It was intended to provide end-to-end digital service using the public telephone networks worldwide and, therefore, to provide high-quality, error-free transmission.