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Glossary of broadband terminology: N

Nail Up

The process of dedicating a telecommunications circuit for a particular use; the physical or logical dedication of a line for a particular use. See also Leased Line.

Narrowband

A term used to describe services with up to and including T-1or 1.544 Mbps.

Narrowband ISDN

Same as ISDN.

NAT

Network Address Translation

Near End CrossTalk

Leakage of undesired local signals into the local retriever; could be from the companion transmitter or other nearby sources.

Network Access Point

A NAP is a public network exchange facility where ISPs can connect with one another in peering arrangements. The NAPs are akey component of the Internet backbone because the connections within them determine how traffic is routed. They are also the points of most Internet congestion.

Network Access Provider

Another name for the provider of networked telephone and associated services, usually in the US.

Network Address Translation

The translation of an Internet Protocol address (IP address) used within one network to a different IP address known within another network. One network is designated the inside network and the other is the outside. Typically, a company maps its local inside network addresses to one or more global outside IP addresses and unmaps the global IP addresses on incoming packets back into local IP addresses. This helps ensure security since each outgoing or incoming request must go through a translation process that also offers the opportunity to qualify or authenticate the request or match it to a previous request. NAT also conserves on the number of global IP addresses that a company needs and it lets the company use a single IP address in its communication with the world.

Network Design Interface Specification

Used for all communication with network adapters. Works primarily with LAN manager and allows multiple protocol stacks to share a single NIC.

Network Interface Card

The circuit board or other form of computer hardware which serves as the interface between a computer, or other form of communicating DTE, and the communications network; in ADSL, a common NIC card is an Ethernet NIC card which serves as the interface to the ADSL modem from the computer. See also Adapter.
An expansion board you plug into or install into a computer so the computer can be connected to a network. Most NICs are designed for a particular type of network, protocol, and media, although some can serve multiple networks.

Network Interface Device

A device that terminates copper pair from the serving central office at the user's destination and which is typically located outside that location.

Network Interface Unit

Same as a Network Interface Device (NID).

Network Management System

That system which allows a provider or enduser to manage portions or all of a telecommunications network; in xDSL, network management systems allow providers to control and monitor those services based on the ADSL streams, at both the physical and logical layers of the services.

Network Service Provider

The term for an organization offering and providing value-added network services on a telecommunications network.

Network Termination Equipment

The equipment at the end of the line.

Network Termination Unit

Equipment at the customer premises which terminates a network access interface.

NIC

see Network Interface Card

Node

A node on a network is usually formed by the presence of a router and user access equipment. Often, several leased lines are joined together at a network node.

Nx64

Describes a contiguous bit stream at the Nx64 Kbps rate to an application. Examples are LAN interconnect and point-to-point videoconferencing.