N

NAC

See network access control (NAC).

NAT

Network Address Translation. See IP proxy.

National Computing Security Center (NCSC)

The agency that developed the Trusted Computer System Evaluation Criteria (TCSEC) and the Trusted Network Interpretation Environmental Guideline (TNIEG).

National Institute of Standards and Technology (NIST)

An agency (formerly known as the National Bureau of Standards [NBS]) that has been involved in developing and supporting standards for the U.S. government for over 100 years. NIST has become involved in cryptography standards, systems, and technology in a variety of areas. It's primarily concerned with governmental systems, where it exercises a great deal of influence.

National Security Agency (NSA)

The U.S. government agency responsible for protecting U.S. communications and producing foreign intelligence information. It was established by presidential directive in 1952 as a separately organized agency within the Department of Defense (DoD).

NCP

See Network Control Protocol (NCP).

NCSC

See National Computing Security Center (NCSC).

NDPS

See Novell Distributed Print Services (NDPS).

NDS

See NetWare Directory Services (NDS).

need-to-know

A method of information dissemination based on passing information only to those who need to know it.

NetBIOS Extended User Interface (NetBEUI)

A protocol used to transport Network Basic Input Output System (NetBIOS) traffic in a LAN.

NetWare Core Protocol (NCP)

The upper-layer NetWare protocol that functions on top of IPX and provides NetWare resource access to workstations. See also Internetwork Packet Exchange (IPX).

NetWare Directory Services (NDS)

A directory management service used to manage all of the resources in a network. In later versions, the acronym was changed to Novell Directory Services, and the service is now known as eDirectory. NDS provides a database of all of the network objects or resources.

NetWare Link State Protocol (NLSP)

A protocol that gathers routing information based on the link-state routing method. Its precursor is the Routing Information Protocol (RIP). NLSP is a more efficient routing protocol than RIP.

NetWare Loadable Module (NLM)

A component used to provide a NetWare server with additional services and functionality. Unneeded services can be unloaded, thereby conserving memory.

network

A group of devices connected by some means for the purpose of sharing information or resources.

network access control (NAC)

The set of standards defined by the network for clients attempting to access it. Usually, NAC requires that clients be virus free and adhere to specified policies before allowing them on the network.

Network Address Translation (NAT)

See IP proxy.

network attached storage

Storage, such as hard drives, attached to a network for the purpose of storing data for clients on the network. Network attached storage is commonly used for backing up data.

network-based IPS (N-IPS)

An intrusion prevention system that is network based. To prevent the intrusion, it must first detect it (thus making it a superset of IDS), and then act accordingly.

Network Basic Input Output System (NetBIOS)

The native protocol of Windows PCs. It provides a 15-character naming convention for resources on the network. NetBIOS is a broadcast-oriented network protocol in that all traffic is available to all devices in a LAN. The protocol can be transported over NetBIOS Extended User Interface (NetBEUI), TCP/IP, or Internetwork Packet Exchange/Sequenced Packet Exchange (IPX/SPX).

Network Control Protocol (NCP)

The protocol Point-to-Point Protocol (PPP) employs for encapsulating network traffic.

Network File System (NFS)

A protocol that enables users to access files on remote computers as if the files were local.

network interface card (NIC)

A physical device that connects computers and other network equipment to the transmission medium.

Network Interface layer

The lowest level of the TCP/IP suite; it is responsible for placing and removing packets on the physical network.

Network layer

The third layer of the OSI model, it is responsible for logical addressing and translating logical names into physical addresses. This layer also controls the routing of data from source to destination as well as the building and dismantling of packets. See also Open Systems Interconnection (OSI) model.

Network Operations Center (NOC)

A single, centralized area for network monitoring and administrative control of systems.

network operating system (NOS)

The software enabling networking; NOS can be on a LAN or WAN.

network sniffer

A device that has access to the signaling on the network cable.

network-based IDS (N-IDS)

An approach to an intrusion detection system (IDS), it attaches the system to a point in the network where it can monitor and report on all network traffic.

network-based IPS (N-IPS)

See host-based IPS (H-IPS).

New Technology LAN Manager (NTLM)

The protocol that Microsoft Windows–based operating systems use for authentication with remote access protocols.

NFS

See Network File System (NFS).

NIC

See network interface card (NIC).

nonessential service

A service that isn't necessary to keep the server operating at the expected level in its expected role.

Noninterference model

A model intended to ensure that higher-level security functions don't interfere with lower-level functions.

nonrepudiation

Verifying (by whatever means) that data was seen by an intended party. It makes sure they received the data and can't repudiate (dispute) that it arrived.

notification

The act of being alerted to an event.

notification policies

A set of rules about what triggers notification.

Novell Distributed Print Services (NDPS)

A Novell-designed printing system that uses NetWare Directory Services (NDS), known as eDirectory in NetWare 6, to install and manage printers. NDPS supports automatic network printer installation, automatic distribution of client printer drivers, and centralized printer management without the use of print queues.

NSA

See National Security Agency (NSA).