N

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n-1: The immediately preceding release of the operating system.
NAK character: See negative acknowledgment character.
named constant: In RPG, a name representing a specific value that does not change during the running of the program.
named mutex: A mutual exclusion lock that has a text name associated with it for identification and debugging purposes.
name pattern: In CoOperative Development Environment/400, a set of criteria used to display a list of VM files, MVS™ data set names, or IBM® i objects.
namespace: Space reserved by a file system to contain the names of its objects.
naming authority: In OSI, an organization that assigns OSI names and addresses--such as abstract syntax names, application context names, network entity titles, and NSAP addresses--to ensure that they are unique.
NaN: See not-a-number. See also decimal floating-point number.
NAT: See network address translation. See also static network address translation.
NAT conversation: A relationship between any of the following IP addresses and port numbers: (1) private source IP address and source port number (without NAT), (2) public (NAT) source IP address and public (NAT) source port number, (3) destination IP address and port number (an external network).
national language: See language load identification.
national language dependent function (NLDF): Any function of a hardware or software product that must be altered to suit a country, region, or language. Examples include date and time formats, monetary values, keyboards, measurement systems, and character data functions (such as sorting). See also national language support, national language version.
national language support (NLS): The features of a product that accommodate a specific region, its language, script, local conventions, and culture. See also localized, national language dependent function.
national language version (NLV): For the secondary language, the textual data for all licensed programs. See also localized, national language dependent function.; For the primary language, the running code and textual data for each licensed program ordered.
native character set: In COBOL, the default character set associated with the computer specified in the OBJECT-COMPUTER paragraph.
native collating sequence: In COBOL, the default collating sequence associated with the computer specified in the OBJECT-COMPUTER paragraph.
natural language: Human language, as opposed to the artificial languages used in computer programming.
natural language processing: Processing that accepts natural language input and produces natural language output. For example, a natural language information retrieval system accepts ordinary text files as input and may identify keywords for information retrieval.
NAU: See network addressable unit.
NAUN: See nearest active upstream neighbor.
NDM: See normal disconnected mode.
nearest active upstream neighbor (NAUN): In the IBM Token-Ring Network, the station sending data directly to another station in the ring.
negate: To make ineffective or not valid.
negated combined condition: In COBOL, the NOT logical operator immediately followed by a combined condition in parentheses.
negated condition: A condition that is made opposite (either true or false), by the NOT logical operator.
negated simple condition: In COBOL, the NOT logical operator immediately followed by a simple condition.
negative acknowledgment character (NAK character): The binary synchronous communication (BSC) transmission control character that indicates that the device is not ready or that an error occurred.
negative response (NR): In SNA, a response indicating that a request did not arrive successfully or was not processed successfully by the receiver. See also positive response.
negotiated release: In OSI, a service provided by the session layer that enables an application entity that has received a release indication to refuse the release and continue the session connection.
negotiation: A two-phase process by which an initiating key server communicates with a responding key server. If the negotiations are successful, the key servers establish a dynamic virtual private network (VPN) connection that is between the two agreed-on endpoints. This approach, which is directed by the Internet Key Exchange (IKE) protocols, maintains the secrecy of keys.
nest: To incorporate a structure or structures into a structure of the same kind; for example, one call instruction (nested call) within another call instruction (nesting call) or one subroutine (nested subroutine) within another subroutine (nesting subroutine).
nested call: A call to a program incorporated within another call to a program within the same job.
nested command: A command or group of commands whose processing is conditioned on the evaluation of a preceding or associated command. Nesting is a structured form of branching. In CL programs, the nested command is merged into an associated command. If the nested command is a DO command, the entire do group is nested.
nested DO group: A DO group that is contained within another DO group.
nested exception: An exception that occurs while another exception is being handled.
NetBIOS (Network Basic Input/Output System): A standard interface to networks and personal computers that is used on local area networks to provide message, print-server, and file-server functions. Application programs that use NetBIOS do not have to handle the details of LAN data link control (DLC) protocols.
Net.Data®: A program with which a user can create interactive Web applications by using macros to add logic, variables, program calls, and report writing to HTML.
netgroup: A network-wide group of hosts and users. A netgroup can be used to restrict access to shared information on Network File Systems (NFS) and to restrict remote access.
net ID (NETID): See network identifier. In TCP/IP, that part of the IP address that defines a network. The length of the network ID depends on the type of network class (A, B, or C).
NETID (network ID, net ID): See network identifier.
netmask: See network mask.
netname: A shared resource on a server. When a netname is assigned to a resource, the user must refer to it by its netname and specify the server where the resource is located.
NetView®: Pertaining to an IBM licensed program that is used to monitor a network, manage it, and diagnose its problems.
network: In data communication, a configuration in which two or more locations are physically connected for the purpose of exchanging data.
network address: An identifier for a node in a network.
network addressable unit (NAU): In SNA networking, any device on the network that has a network address, including logical units, physical units, and system service control points.
network address translation (NAT): The conversion of a network address that is assigned to a logical unit in one network into an address in an adjacent network. See also static network address translation.; In a firewall, the conversion of secure Internet Protocol (IP) addresses to external registered addresses. This enables communications with external networks but masks the IP addresses that are used inside the firewall.
network administrator: A person who defines the network configuration and other network-related information. This person controls how an enterprise or system uses its network resources.
network architecture: The logical structure and operating principles of a computer network. The operating principles of a network include those of services, functions, and protocols.
network attribute: Control information about the communications environment. System name and default local location name are examples of network attributes. See also system value.
network authentication service: The IBM i implementation of the Kerberos V5 standard protocol that enables the System i® product and several System i services (such as IBM System i5® Access for Windows) to use for authentication a Kerberos ticket as an optional replacement for a user name and password.
Network Basic Input/Output System: See NetBIOS.
network class: The type of TCP/IP network, such as Class A, Class B, or Class C.
network computing: The use of a scalable distributed computing infrastructure that encompasses the key elements of networking technologies. Examples are systems and network management; the Internet and intranets; clients and servers; application programs, databases; transaction processing; and various operating systems and communication protocols.
network driver: A program that allows two or more computers or work stations to interoperate over a communications network. The computers or work stations may be heterogeneous or homogeneous devices. Services provided by a network driver can include file sharing, remote database access, electronic mail, remote print services, time services, security services, data conversion, remote function call, and work station emulation.
network driver for Microsoft Windows: In System i Access, a program that integrates System i Access functions with the standard user interface in the Microsoft Windows program. The Windows network driver allows a Windows user to redirect print files to a System i server (using the virtual print function), manage these redirected printer files (using Windows Print Manager), and use remote System i server files (using the shared folders function).
network entity: In OSI, a component, such as the OSI Communications Subsystem network layer, that provides network services for an open system.
network entity title: In OSI, a title that identifies the network entity on a given node. Because a node can have only one network entity, the network entity title uniquely identifies a given node. Network entity titles are represented in the same format as NSAP addresses.
network entity title nickname: In OSI, a nickname that identifies a network entity title.
network file: In object distribution, a file (either a physical file or a save file) sent by one user to one or more other users. A network file is placed on the recipient's message queue when it arrives at the destination system.
Network File System (NFS): A protocol, developed by Sun Microsystems, Incorporated, that allows a computer to access files over a network as if they were on its local disks.
network group: In Backup, Recovery, and Media Services, a cluster of systems sharing a common media inventory. Available tapes are eligible for use by any system in the network group. Each system in the network group receives updates to the media inventory, regardless of which network member makes the change.
network ID (NETID): See network identifier. In TCP/IP, that part of the IP address that defines a network. The length of the network ID depends on the type of network class (A, B, or C).
network identifier (network ID, net ID, NETID): In TCP/IP, that part of the IP address that defines a network. The length of the network ID depends on the type of network class (A, B, or C).
Network Information Service (NIS): A set of protocols, developed by Sun Microsystems, that are used to provide directory services for network information.
network interface (NWI): The physical interface that allows a user to connect to the integrated services digital network (ISDN).
network interface controller (NIC): Hardware that provides the interface control between system main storage and external high-speed link (HSL) ports.
network interface description: An IBM i communications object that represents the physical interface to the integrated services digital network (ISDN). The network interface description must be configured in addition to the line, controller, and device descriptions. The system-recognized identifier for the object type is *NWID.
network job: In object distribution, a batch input stream sent by one user to one or more users in the network as defined in the system distribution directory.
network job entry (NJE): In object distribution, an entry in the network job table that specifies the system action required for incoming network jobs sent by a particular user or group of users. Each entry is identified by the user ID of the originating user or group.
network job table: In object distribution, a table containing entries that control the system action required for incoming network jobs.
network layer: In OSI architecture, the layer that provides services to establish a path between open systems with a predictable quality of service.
network-layer protocol data unit (NPDU): In OSI, a protocol data unit in the network layer. (I)
network-layer service access point: In OSI, a service access point in the network layer. (I)
network-layer service data unit (NSDU): In OSI, a unit of data transferred between the transport layer and the network layer.
network management: In OSI, systems management that involves processing and exchanging management information over two or more nodes. Network management provides the ability to manage one or more nodes from another node.; The process of planning, organizing, and controlling a communications-oriented system.
network management association: In OSI, an ACSE association between two systems management application entities (SMAEs)--one representing a managing process, the other representing an agent process. After network management associations are established, a manager can send operator commands to its agents and an agent can send event reports to its managers.
network management domain: In OSI, a manager and the agents that it manages. An agent can participate in more than one network management domain. In OSI Communications Subsystem, the agent at a local node is always part of the management domain of the manager at that local node.
network mask (netmask): A number that is the same as an Internet Protocol (IP) address. A network mask identifies which part of an address is to be used for an operation, such as making a TCP/IP connection.
network message: In object distribution, a message sent by one user to one or more users enrolled in the system distribution directory with the Send Network Message (SNDNETMSG) command.
network mode: See network QOS mode.
Network News Transfer Protocol (NNTP): A protocol that is used to post messages in, distribute messages to, and retrieve messages from newsgroups and to transfer articles between news servers.
network node: A node that can define the paths or routes, control route selection, and handle directory services for the APPN function.
network node control point (NNCP): A control point that provides session and routing services to adjacent end nodes.
network node server: A network node that is directly connected to an end node or a low-entry networking end node, and has been assigned to service the end node session requests.
network operator: A person who controls the day to day operation of all or part of a network.
network path: In System i Access, the system, path, or library, and the name of the server network driver, network printer, or data queue that the user is accessing. For example, the network path used to access a printer through the network driver is: //system/library/printer.
network protocol: A communication protocol from the Network Layer of the Open Systems Interconnect (OSI) network architecture, such as the Internet Protocol (IP).
network QOS mode (network mode): In the OSI Communications Subsystem licensed program, a set of X.25 connection-mode quality-of-service (QOS) values that determine the type of connection established between two nodes.
network resource: In OSI, a general term for resources available to the network, such as lines and line sets.
network routing facility (NRF): An IBM i function that runs with the Network Routing Facility licensed program to allow the path for data to go from a display station to a server application.
Network Routing Facility: A licensed program that runs under the control of the Network Control Program and uses a System/370 backbone network. The network routing facility provides primary logical unit support and a path for data between a display station and an application without using the System/370 host system.
network server description (NWSD): An object that contains a description of the characteristics of a file server I/O processor that is attached to the system.
network termination (NT): In ISDN, equipment that provides the function necessary for the operation of the access protocols by the network.
network termination 1 (NT1): In ISDN, an end point for the network's transmission line. Network termination 1 is responsible for the physical layer characteristics (of the OSI reference model), such as ending the line transmission, monitoring performance, and timing.
network termination 2 (NT2): In ISDN, an end point for the network's transmission line. Network termination 2 is responsible for the network layer, the data link layer, and the remaining functions of the physical layer (not included in network termination 1) of the OSI reference model. Examples include communications controllers and public branch exchanges (PBXs).
Network Time Protocol: A clock synchronization protocol commonly used on an internet.
network topology database: The representation of the current topology of the intermediate routing portion of the APPN network. The network topology database contains entries for network nodes and the transmission groups interconnecting them. Each entry describes the current characteristics of the node or transmission group that it represents. The topology database is used to determine the preferred session route between two end nodes for a given class of service.; In Managed System Services, a set of database files that contain topology information and general system information for nodes throughout the network.
network user identification (NUI): In X.25, the network specific information that enables the transmitting data terminal equipment (DTE) to provide billing, security, or management information on a per-call basis to the data circuit-terminating equipment (DCE). The NUI can identify a network user independently of the port being used.
network virtual terminal (NVT): A Telnet service that provides a default common interface to remote terminals. The client application negotiates NVT support and, as a result, the Telnet server maps 5250 functions to virtual terminal characters.
neutral color: In the GDDM function, one of the colors selected to display graphics primitives; for example, white on a display or black on a printer. See also background color.
next operable sentence: In COBOL, the next sentence to which control will be transferred after the running of the current statement is complete.
next record: The record that logically follows the current record of a file.
next system: A node in the SNADS network that is physically connected to the local system, and through which distribution items can be routed.
next system queue: In SNADS, a queue that is used to hold distribution items that are being routed to a next system.
next system table: In SNADS, a table identifying all the systems physically connected to the local system.
NFS: See Network File System.
NIC: See network interface controller.
nickname: In the OSI Communications Subsystem licensed program, a 1- to 8-character name that identifies an object or entity in an OSI network. Nicknames are provided by OSI Communications Subsystem to enable users to use simple names instead of the often long, multipart, sometimes binary-coded identifiers required by OSI protocols.
NIS: See Network Information Service.
NJE: See network job entry.
NLDF: See national language dependent function. See also national language support, national language version.
NLS: See national language support. See also localized, national language dependent function.
NLS-enabled: Pertaining to any product that is internationalized and localized.
NLV: See national language version.
NNCP: See network node control point.
NNTP: See Network News Transfer Protocol.
node: One of the points in a topology view or topology diagram. A node usually corresponds to a machine, but depending on the type of view, might also correspond to a facility, base product, solution element, or solution artifact.; In X.25, a point where packets are received, stored, and forwarded to another location (or data terminal equipment) according to a routing method defined for the network.; In networking, a point capable of sending and receiving data. A node can be a device, such as printer or workstation, a system, or a storage location on a disk. See also port.; A location in a communications network that provides host-processing services.; In hardware, a uniprocessor or symmetric multiprocessor (SMP) computer that is part of a clustered system or a massively parallel processing (MPP) system.
node list: A system object that contains a list of SNA nodes identified by an APPN network ID and control point name. The system-recognized identifier for the object type is *NODL.
node name: The name assigned to a node during network definition.
node-to-node communication: Internal communication between clustered nodes uses the virtual Ethernet as the private network (or interconnect) that carries the heartbeat. The cluster service on each node uses a heartbeat to keep track of the current state of the nodes within the cluster. The cluster service uses the heartbeat to: (1) Determine when a failover to another node should occur, (2) Synchronize the cluster databases on each node, (3) Verify node failures during a cluster configuration change. The private network uses the single network virtual Ethernet model.
node type: The designation of a node according to the protocols it supports or the role it plays in a network. Examples of Advanced Peer-to-Peer Networking (APPN) node types are network node and end node.
nonadjacent destination node: In the OSI Communications Subsystem licensed program, a destination node that is connected to a different subnetwork from the local node. To communicate with a nonadjacent destination node requires the use of a relay node. See also adjacent destination node.
nonce: A random, unique text string that is encrypted along with data and then is used to detect attacks against the system that sends the encrypted data. A nonce is used especially for authentication and ensures that encrypted data is different each time that it is encrypted.
noncontiguous item: In COBOL, a data item in the Working-Storage and Linkage Sections of the Data Division that bears no relationship to other data items.
nonexecutable statement: In DB2® for IBM i, an SQL statement that can be embedded only in an application program.
nonexposed name: In DB2 for IBM i, a table name or view name for which a correlation name is specified.
nongeneric alert: In SNA management services (SNA/MS), alert information that is encoded such that it conveys to the receiver the set of screens that should be displayed for the network operator when the alert is received. The use of nongeneric alerts requires that the receiver recognize and understand each unique problem for which an alert is sent. See also generic alert.
nonhosted partition: A logical partition that is not dependent on a logical partition for I/O resources.
noninteractive transaction: The work done by jobs and tasks, such as batch jobs and system activity, that may have occurred as a result of an interactive transaction. See also interactive transaction.
nonlabeled tape: A tape that has no labels. Tape marks are used to indicate the end of the volume and the end of each data file.
nonlibrary user ASP: An auxiliary storage pool that contains journals, journal receivers, and save files. The libraries for the objects are in the system ASP. See also library user ASP.
nonnumeric item: In COBOL, a data item that is alphanumeric, alphabetic, or Boolean.
nonnumeric literal: In COBOL, a character string bounded by quotation marks, whose value is itself.
nonpaired data: In Business Graphics Utility and the GDDM function, data that is specified such that each X-value has a set of Y-values associated with it. See also paired data.
nonpersistent message: A message that does not survive a restart of the queue manager. See also persistent message.
nonproduct object: In System Manager, an application object that has not been packaged as part of a product.
nonprogrammable workstation (NWS): A workstation that does not have processing capability and does not allow the user to change its functions.
nonrepudiation: Proof that a transaction occurred or that a message was sent or received. The use of digital certificates and public key cryptography to digitally sign transactions, messages, and documents supports nonrepudiation.
nonresponse mode: In IMS™, a mode of terminal operation that allows asynchronous operations between the terminal operator and the application program. See also response mode.
nonrestricted state: The state of a system meaning any or all subsystems are active, regardless of whether there are any active jobs or users at the time.
nonsecure network: A set of nodes that are not controlled by a single administrative party. See also secure network.
nonstandard labeled tape: A tape that has labels but does not follow IBM labeling conventions.
nonswitched line: A connection between computers or devices that does not have to be made by dialing. See also switched line.
no-print border: A small area on the edges of a physical page where data will not print. This no-print border is a limitation of the printer.
no response: In SNA, a value in the form-of-response-requested field of the request header that directs the receiver of the request not to return any response, regardless of whether or not the request is received and processed successfully. See also definite response, exception response.
normal control field: For the sort function, any control field that is specified by an N in column 7 of the field sequence specification.
normal disconnected mode (NDM): A nonoperational mode of an unbalanced data link in which the secondary station is logically disconnected from the data link and, therefore, cannot transmit or receive information.
normal installation: A process in which the IBM i operating system contained on tape is installed in auxiliary storage, replacing the operating system (if any) that is currently in the system. See also abbreviated installation.
normal queue: In SNADS, a queue that contains distribution entries with a service level of data low. See also priority queue.
normal response mode (NRM): An operational mode of an unbalanced data link in which the secondary station starts transmission only as the result of receiving explicit permission, by polling, from the primary station. See also asynchronous balanced mode.
not-a-number (NaN): In binary floating-point and decimal floating-point concepts, a value, not interpreted as a mathematical value, that contains a mask and a sequence of digits. See also decimal floating-point number.
notation: A system of characters, symbols, or abbreviated expressions used to express technical facts or qualities.
notebook: In graphical user interfaces (GUIs), a control that resembles a tabbed notebook, with multiple pages that can be accessed individually in any order.
Notes® server: Application software that runs on a machine that is connected to a network. The Notes server provides the following services to Notes clients and other Notes servers: storage and replication of databases, directory services, mail routing, and security.
not-found indicator: An indicator that is set on when the specified record cannot be found.
notification: An unscheduled, spontaneously generated message, issued by an agent when a significant or critical (data) condition occurs.; Information, labeled as a managed object, that relates to an event that has occurred within the managed object.
notify delivery: The method of delivering messages to a message queue in which the work station user is notified that a message arrived. The signal is a light or an audible alarm.
notify message: A message that describes a condition for which a program requires a reply from the calling program, or for which a reply is automatically sent to the program.
notify object: A message queue, a data area, or a database file that contains information identifying the last successful commitment operation. This information can be used by the programmer to find a restarting point for an application following an abnormal end to the system or routing step processing.
not ready: Pertaining to a status where all images in the image catalog are not available for use by the virtual optical device. The status of the individual image catalog entry images in the image catalog reflects either the last status for the catalog before being made not ready from ready or the future status for catalogs about to be made ready. The image catalog can be made not ready by using the LODIMGCLG command with OPTION(*UNLOAD).
NPDU: See network-layer protocol data unit.
NR: See negative response. See also positive response.
NRF: See network routing facility.
NRM: See normal response mode. See also asynchronous balanced mode.
NSAP address: In OSI, an address that identifies a service access point in the network layer. NSAP addresses must be unique within the OSI network where they are used. NSAP addresses are assigned by naming authorities.
NSAP nickname: In OSI, a nickname that identifies an NSAP address.
NSDU: See network-layer service data unit.
NT: See network termination.
NT1: See network termination 1.
NT2: See network termination 2.
NUI: See network user identification.
NUI service facility: In X.25, a facility sent by the data terminal equipment (DTE) to the network in call setup packets that contain a network-assigned identifier, which can be used for billing, security, or network management purposes. The NUI service facility can also be used to select specific optional facilities to be associated with a virtual call.
NUL: See null character.
NULL: In SQL, the value denoting the absence of data for a particular row and column.
null-capable field: A field whose value can be null.
null character (NUL): The character with the value of X'00' that represents the absence of a displayed or printed character.
null clause: In REXX, a clause consisting of only blanks, comments, or both. A null clause is ignored.
null record: In binary synchronous communications, a record that contains no data, only the data link control characters STX ETX.
null statement: A statement that contains only the delimiter symbol, but no characters.
null string: A character or bit string with a length of zero.
null-terminated host variable: A varying-length host variable in which the end of the data is indicated by the presence of a null terminator.
null terminator: In C, the value that indicates the end of a string. For EBCDIC, ASCII, and Unicode UTF-8 strings, the null terminator is a single-byte value (X'00'). For Unicode UTF-16 and UCS-2 (wide) strings, the null terminator is a double-byte value (X'0000').
null value: A parameter position for which no value is specified.
number: In REXX, a character string consisting of one or more decimal digits optionally preceded by a plus or minus sign, and optionally including a single period that represents a decimal point. A number can also have a power of 10 suffix in conventional exponential notation: an E (uppercase or lowercase) followed optionally by a plus or minus sign then followed by one or more decimal digits defining the power of 10.
numeric character: See digit.
numeric constant: The actual numeric value to be used in processing, instead of the name of a field containing the data. A numeric constant can contain any of the numeric digits 0 through 9, a sign (plus or minus), and a decimal point. See also character constant.
numeric digit: In REXX, a pattern that specifies, by column number, how input data is to be parsed.
numeric edited item: In COBOL, a numeric item whose PICTURE character-string contains valid editing characters.
numeric expression: A numeric constant, a simple numeric variable, a scalar reference to a numeric array, a numeric-valued function reference, or a sequence of the above, separated by numeric operators and parentheses.
numeric field: An area that is reserved for a particular unit of information and that can contain only the digits 0 through 9. See also character field.
numeric item: In COBOL, a data item that must be numeric. If signed, the item can also contain a representation of an operational sign.
numeric operator: A symbol representing an operation to be performed on numeric data, such as + or - to indicate addition or subtraction.
numeric pattern: In REXX, a pattern that specifies, by column number, how input data is to be parsed.
numeric variable: The name of a numeric data item whose value is assigned or changed during program processing.
N-up: The partitioning of a side of a sheet into a fixed number of equal size partitions. For example, 4-up divides each side of a sheet into four equal partitions.
NVT: See network virtual terminal.
n-way: Any valid configuration of processors for a system that is capable of supporting 1 to n processors.
n-way processor architecture: A processor architecture that provides expandability for future system growth by allowing for additional processors. To the user, the additional processors are transparent because they separately manage the work load by sharing the work evenly among the n-way processors.
NWI: See network interface.
NWS: See nonprogrammable workstation.
NWSD: See network server description.