SNIA Online Dictionary

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NAA	[Network], [Standards] Acronym for Network Address Authority.
Name Server	[Network], [Fibre Channel] [Fibre Channel] A distributed service provided by the Fibre Channel Fabric to register and discover the attributes of Fibre Channel N_Ports. Once registered, the attributes may be viewed by requesting N-ports. [Network] Another name for the DNS server.
namespace	[General], [NVMe], [Management], [File System] [General] A domain of identifiers. [File System] The set of valid names recognized by a file system. [Management] In CIM and WBEM, a collection of object definitions and instances that are logically consistent. [NVMe] Formatted non-volatile storage that may be accessed by a host. For example, an NVMe namespace may contain logical blocks for storing data or key-value pairs for storing data.
Name_Identifier	[Fibre Channel] An identifier used to identify entities in Fibre Channel. Example Name_Identifiers are Port_Name and Node_Name.
NAND	[General], [Hardware] [General] The boolean logic operation ‘not and’. [Hardware] A type of non-volatile memory commonly used in flash memory.
NAS	[Network], [Storage System] Acronym for Network Attached Storage.
National Institute of Standards and Technology	[Data Security], [Standards] A non-regulatory federal agency within the U.S. Commerce Department's Technology Administration. National Institute of Standards and Technology’s (NIST) mission is to develop and promote measurement, standards, and technology to enhance productivity, facilitate trade, and improve the quality of life.
native data format	[Legal] The original, non-derived format and structure of data, together with its associated metadata. Where data is unstructured, native file format means the original format of a file. While structured data or unstructured data may be read by other programs, native data format means data whose state and integrity are unchanged since generation by its instantiating application.
Native Fabric	[Fibre Channel] In Inter-Fabric Routing, the local Fibre Channel Fabric where the Native Nx_Port resides.
Native Nx_Port	[Fibre Channel] A role of an Nx_Port in an IFR environment. A Native Nx_Port is physically attached to the local fabric.
NDMP	[Management], [Network] Acronym for Network Data Management Protocol.
NDU	[Hardware], [Computer System] Acronym for non-disruptive upgrade.
near-online data	[Data Management] Data that is accessible within some moderate length of time, usually some number of seconds. See active data, offline data.
near-online storage	[Storage], [Energy] [Storage] Storage that is accessible within some moderate length of time, usually some number of seconds. [Energy] Storage systems with first data access times > 80 ms and less than several seconds, as specified in the SNIA Emerald™ Power Efficiency Measurement Specification.
network	[Network] An interconnect that enables communication among a collection of attached nodes. A network consists of optical or electrical transmission media, infrastructure in the form of hubs and/or switches, and protocols that make message sequences meaningful. In comparison to I/O interconnects, networks are typically characterized by large numbers of nodes that act as peers, large inter-node separation, and flexible configurability. See channel, I/O interconnect, local area network, storage area network.
network adapter	[Network] An adapter that connects an intelligent device to a network, also called a network interface card, or NIC. See Ethernet adapter, NIC.
Network Address Authority	[Network], [Fibre Channel] 1. [Network] A management authority that allocates addresses used to create unique names. 2. [Fibre Channel] A 4-bit field used to identify the controlling authority for guaranteeing uniqueness of World Wide Names (WWNs). In a Fibre Channel environment, several Naming Authorities can be active at the same time, therefore Fibre Channel prepends the NAA field to World Wide Names to guarantee global uniqueness. An NAA =1, for example, indicates IEEE 48-bit Identifiers.
Network Attached Storage	[Storage System] A storage device that connects to a network and provides file access services to clients. Network Attached Storage (NAS) devices generally consist of an engine that implements file services and one or more storage devices. File services are provided to clients using file access protocols such as NFS and SMB. See storage area network.
network backup	[Data Recovery] A backup methodology that copies data over a network to a backup server.
Network Data Management Protocol	[Data Recovery] A communications protocol that allows data storage devices, robotic library devices, and backup applications to intercommunicate for the purpose of performing backups. Network Data Management Protocol (NDMP) is an open standard protocol for network-based backup of NAS devices. It allows a network backup application to control the retrieval of data from, and backup of, a server. The control and data transfer components of backup and restore are separated. NDMP is intended to support tape drives and can be extended to address other devices and media. The SNIA offers an NDMP v4 reference implementation.
Network File System	[File System], [Standards] A family of network protocols defined by the IETF to access a file system.
Network Interface Card	[Network] An I/O adapter that connects a node to a network. A network interface card (NIC) is commonly a plug-in circuit board, however, the term is also used to denote an ASIC or set of ASICs on a computer system board that perform the network I/O adapter function. The term NIC is universally used in Ethernet context. In Fibre Channel contexts, the terms host bus adapter, HBA and adapter are used in preference to NIC. See host bus adapter, I/O adapter.
nexus	[SCSI] A temporary relationship, consisting of at least a target identifier and initiator identifier, between two SCSI devices.
NFS	[File System], [Standards] Abbreviation for Network File System.
NIC	[Network] Acronym for Network Interface Card.
NIST	[Data Security] Acronym for National Institute of Standards and Technology.
NL_Port	[Fibre Channel] An Nx_Port that is communicating via an Arbitrated Loop.
node	[Network] An addressable entity connected to an I/O interconnect or network. The term node is used to refer to computers, storage devices, and network interconnection devices such as switches, routers and gateways. The component of a node that connects to the bus or network is a port.
Node_Name	[Fibre Channel] A Name-Identifier that is associated with a Fibre Channel node.
non-blocking	[Network], [Computer System] [Computer System] A property of an operation such that the operation does not stop and wait for other operations to occur. [Computer System] A property of an operation such that the operation does not cause delay in other operations. [Network] A property of a switch such that one data path through the switch does not delay the flow of traffic on another data path through that switch.
non-disruptive serviceability	[Hardware], [Computer System] Support for continued availability of data during FRU service operations. Some examples of non-disruptive serviceability are code patches, software/firmware upgrades, configuration changes, data migrations, and system expansion done during production time. Non-disruptive service operations may result in performance impacts to data availability but do not result in a loss of access.
non-disruptive upgrade	[Hardware], [Computer System] A type of non-disruptive serviceability that upgrades the entity without impacting availability of that entity during the upgrade process.
non-erasable content	[Data Management] Content that should not be deleted except in accordance with a retention policy.
non-linear mapping	[Storage System] Any form of tabular mapping in which there is not a fixed size correspondence between mapped address spaces. Non-linear mapping is required in disk arrays that compress data, since the space required to store a given range of virtual blocks depends on the degree to which the contents of those blocks can be compressed, and therefore changes as block contents change. See algorithmic mapping, dynamic mapping, tabular mapping.
non-transparent failover	[Computer System] A failover, visible to external components of a system, of one component of that system to another component of that system. An example is a controller failover in a redundant disk subsystem if the surviving controller exports the other's virtual disks at different addresses or on a different host I/O interconnect. See transparent failover.
non-uniform memory access	[Hardware] A computer architecture with memory shared by multiple processors, but with different processors having different access times to memory.
Non-Uniform Memory Architecture	[Computer System] A computer architecture that enables memory to be shared by multiple processors, but with different processors having different access speeds to different parts of the memory.
non-volatile	[Storage System] The property that data is preserved in the absence of electrical power.
non-volatile cache	[Storage System] A cache that retains data through power cycles.
non-Volatile Dual Inline Memory Module	[Hardware] A dual inline memory module (DIMM) that operates as standard RAM while also having persistence across power cycles.
non-volatile memory	[Computer System] Synonym for non-volatile random access memory.
non-volatile random access memory	[Computer System] Computer system random access memory that preserves data over power failures. Non-volatile random access memory (NVRAM) is typically implemented through the use of UPS, batteries, or implementation technology such as flash memory.
non-volatility	[Storage System] The property of an electronic device that data is preserved even when electrical power is removed.
nonrepudiation	[Data Security] Ability to prove the occurrence of a claimed event or action and its originating entities [ISO/IEC 27000].
NPIV	[Fibre Channel] Acronym for N_Port_ID Virtualization.
NQN	[NVMe] Shorthand for NVMe Qualified Name.
NUMA	[Computer System] Abbreviation for non-uniform memory access.
NVDIMM	[Hardware] Acronym for non-volatile dual inline memory module.
NVDIMM-F	[Hardware] A non-volatile dual in-line memory module that is accessed using a block access protocol.
NVDIMM-N	[Hardware] A dual in-line memory module that operates as non-volatile DRAM.
NVDIMM-P	[Hardware] A dual in-line memory module that operates as non-volatile DRAM (NVDIMM-N) and also as a non-volatile block-accessed device (NVDIMM-F).
NVM	[Computer System] Shorthand for non-volatile memory.
NVM Express Management Interface	[NVMe], [Management] A protocol for managing an NVMe subsystem that is carried over a management bus such as MCTP.
NVM Express™	[Storage System], [Standards] 1. [Standards] An organization responsible for developing the family of NVM Express specifications and marketing NVM Express technologies. The NVM Express Work Group was incorporated as NVM Express in 2014. 2. [Storage System] NVM Express (NVMe™) is an open collection of standards and information created to fully expose the benefits of non-volatile memory in all types of computing environments from mobile to data center. The family of NVMe specifications defines how host software communicates with non-volatile memory.
NVM subsystem	[NVMe] A device that implements the NVMe protocol.
NVMe	[NVMe] An acronym for NVM Express™.
NVMe command	[NVMe] A command issued by an NVMe host to an NVMe controller.
NVMe Completion Queue	[NVMe] ] A circular buffer used to return status for completed NVMe commands.
NVMe host	[NVMe] An entity that submits NVMe commands to an NVMe controller through an SQ for processing and receives NVMe command completions from that controller through a CQ.
NVMe host port	[Fibre Channel] VN_Port that acts as an interface between an NVMe host and an NVMe/FC Fabric.
NVMe over fabrics	[NVMe] A protocol that supports message-based NVMe operations over a network fabric. Example network fabrics include Ethernet, Fibre Channel, and InfiniBand.
NVMe over Fibre Channel	[Fibre Channel] A protocol defined by the INCITS Fibre Channel (T11) Technical Committee FC-NVMe standard.
NVMe Qualified Name	[NVMe] Name that uniquely describe an NVMe host or NVM subsystem.
NVMe Submission Queue	[NVMe] A circular buffer used to submit NVMe commands for processing.
NVMe subsystem	[NVMe] A component that processes NVMe commands.
NVMe-MI™	[NVMe], [Management] An acronym for NVM Express Management Interface.
NVMe-oF™	[NVMe] An acronym for NVMe over Fabrics.
NVMe/FC	[Fibre Channel] An acronym for NVM Express over Fibre Channel.
NVMe_DATA IUs	[Fibre Channel] The FC-NVMe Information Unit for data frame(s) transfers.
NVMe_Port	Nx_Port that supports the FC-NVMe standard.
NVRAM	[Computer System] Acronym for non-volatile random access memory.
NVRAM cache	[Storage System] A quantity of NVRAM used as a cache. NVRAM cache is particularly useful in RAID array subsystems, filers, database servers, and other intelligent devices that must keep track of the state of multi-step I/O operations even if power fails during the execution of the steps. It also allows arrays to reply to writes before they are committed to disk, as the NVRAM becomes the non-volatile store for the writes.
NVRAM card	[Computer System] A printed circuit module containing NVRAM.
Nx_Port	[Fibre Channel] An end point for Fibre Channel frame communication, having a distinct address identifier and Name_Identifier, providing an independent set of Fibre Channel functions.
N_Port	[Fibre Channel] A port that connects via a point-to-point link to either a single N_Port or a single F_Port.
N_Port Login	[Fibre Channel] The port-to-port login process by which Fibre Channel end devices establish sessions.
N_Port_ID	[Fibre Channel] A unique 24 bit address used for frame routing that is assigned to an N_Port or NL_Port.
N_Port_ID Virtualization	[Fibre Channel] The ability of an F_Port or a PN_Port to support more than one VN_Port on a single point-to-point link.
N_Port_Name	[Fibre Channel] A Name-Identifier associated with an N_Port.