Networking and communications

Terms related to networking and communications, including definitions about network protocols and words and phrases about data transmission.
  • network operating system (NOS) - A network operating system (NOS) is a computer operating system (OS) that's designed primarily to support workstations, PCs and, in some instances, older terminals that are connected on a local area network (LAN).
  • network operations center (NOC) - A network operations center (NOC) is a centralized place from which enterprise information technology (IT) administrators -- either internal or third party -- supervise, monitor and maintain a telecommunications network.
  • network packet - A network packet is a basic unit of data that's grouped together and transferred over a computer network, typically a packet-switched network, such as the internet.
  • network performance monitoring (NPM) - Network performance monitoring (NPM) is the process of measuring and monitoring the quality of service of a network.
  • network protocol - A network protocol is a set of established rules that specify how to format, send and receive data so that computer network endpoints, including computers, servers, routers and virtual machines, can communicate despite differences in their underlying infrastructures, designs or standards.
  • network service provider (NSP) - A network service provider (NSP) is a company that owns, operates and sells access to internet backbone infrastructure and services.
  • network switch - A network switch connects devices in a network to each other, enabling them to talk by exchanging data packets.
  • network topology - A network topology is the physical and logical arrangement of nodes and connections in a network.
  • network traffic - Network traffic is the amount of data that moves across a network during any given time.
  • Next Hop Resolution Protocol (NHRP) - Next Hop Resolution Protocol (NHRP) is an automated configuration technology that routes data on a distributed network by discovering the best routing path between endpoints.
  • NFV MANO (network functions virtualization management and orchestration) - NFV MANO (network functions virtualization management and orchestration), also called MANO, is an architectural framework for managing and orchestrating virtualized network functions (VNFs) and other software components.
  • NFVi (network functions virtualization infrastructure) - NFVi (network functions virtualization infrastructure) encompasses all of the networking hardware and software needed to support and connect virtual network functions in carrier networks.
  • nibble - In computing and digital technology, a nibble is four consecutive binary digits or half of an 8-bit byte.
  • nslookup - Nslookup is the name of a program that lets users enter a host name and find out the corresponding IP address or domain name system (DNS) record.
  • NVGRE (Network Virtualization using Generic Routing Encapsulation) - NVGRE (Network Virtualization using Generic Routing Encapsulation) is a network virtualization method that uses encapsulation to create large numbers of virtual LANs (VLANs) for subnets that can extend across dispersed data centers and Layers 2 and 3.
  • OAuth (Open Authorization) - OAuth (Open Authorization) is an open standard authorization framework for token-based authorization on the internet.
  • ONC (Office of the National Coordinator for Health Information Technology) - The Office of the National Coordinator for Health Information Technology, abbreviated ONC, is an entity within the U.
  • ONOS (Open Network Operating System) - Open Network Operating System (ONOS) is an OS designed to help network service providers build carrier-grade software-defined networks architected for high scalability, availability and performance.
  • Open Grid Services Architecture (OGSA) - The Open Grid Services Architecture (OGSA) is a set of standards defining the way in which information is shared among diverse components of large, heterogeneous grid systems.
  • operational support system (OSS) - An operational support system (OSS) is a set of programs that helps a communications service provider monitor, control, analyze and manage a telephone or computer network.
  • orthogonal frequency-division multiplexing (OFDM) - Orthogonal frequency-division multiplexing (OFDM) is a method of data transmission where a single information stream is split among several closely spaced narrowband subchannel frequencies instead of a single wideband channel frequency.
  • OSI model (Open Systems Interconnection) - OSI (Open Systems Interconnection) is a reference model for how applications communicate over a network.
  • packet coalescing - Packet coalescing involves using a computer's network interface card (NIC) to reduce the number of generated receive interrupts the adapter issues.
  • packet filtering - Packet filtering is the process of passing or blocking data packets at a network interface by a firewall based on source and destination addresses, ports or protocols.
  • packet loss - Packet loss is when one or more transmitted data packets fail to arrive at their destination.
  • payload (computing) - In computing, a payload is the carrying capacity of a packet or other transmission data unit.
  • peer-to-peer network (P2P network) - A peer-to-peer (P2P) network is a network in which each computer functions as a client or server for other computers in the network.
  • Peripheral Component Interconnect Express (PCIe, PCI-E) - Peripheral Component Interconnect Express (PCIe or PCI-E) is a serial expansion bus standard for connecting a computer to one or more peripheral devices.
  • persistent connection - A persistent connection, also known as an HTTP persistent connection, refers to a network communication channel that remains open for further HTTP requests and responses instead of closing after a single exchange.
  • physical layer - The physical layer is the first and lowest layer of the Open Systems Interconnection (OSI) communications model.
  • PIO (Programmed Input/Output) - Programmed Input/Output (PIO) is a way of moving data between devices in a computer in which all data must pass through the processor.
  • plane (in networking) - A plane is an integral component of telecommunications architecture and networks.
  • Point-to-Point Protocol (PPP) - Point-to-Point Protocol (PPP) refers to a suite of computer communication protocols that provide a standard way to transport multiprotocol data over point-to-point links.
  • Point-to-Point Protocol over Ethernet (PPPoE) - Point-to-Point Protocol over Ethernet (PPPoE) is a network protocol that facilitates communication between network endpoints.
  • preamble - A preamble is a signal used in network communications to synchronize transmission timing between two or more systems.
  • presentation layer - The presentation layer resides at Layer 6 of the Open Systems Interconnection (OSI) communications model and ensures that communications that pass through it are in the appropriate form for the recipient application.
  • private branch exchange (PBX) - A private branch exchange is a telephone system within an enterprise that switches calls between users on local lines, while enabling all users to share a certain number of external phone lines.
  • private IP address - A private IP address is a range of non-internet facing IP addresses used in an internal network.
  • processing in memory (PIM) - Processing in memory, or PIM (sometimes called processor in memory), refers to the integration of a processor with Random Access Memory (RAM) on a single chip.
  • programmable network (network programmability) - A programmable network is one in which the behavior of network devices and flow control is handled by software that operates independently of network hardware.
  • promiscuous mode - In computer networking, promiscuous mode is a mode of operation, as well as a security, monitoring and administration technique.
  • propagation delay - Propagation delay is the amount of time required for a signal to be received after it has been sent; it is caused by the time it takes for the signal to travel through a medium.
  • QAM (quadrature amplitude modulation) - QAM (quadrature amplitude modulation) is a method of combining two amplitude modulation (AM) signals into a single channel.
  • quality of service (QoS) - Quality of service (QOS) refers to any technology that manages data traffic to reduce packet loss, latency and jitter on a network.
  • radio access network (RAN) - A radio access network (RAN) is a major component of a wireless telecommunications system that connects individual devices to other parts of a network through a radio link.
  • RADIUS (Remote Authentication Dial-In User Service) - RADIUS (Remote Authentication Dial-In User Service) is a client-server protocol and software that enables remote access servers to communicate with a central server to authenticate dial-in users and authorize their access to the requested system or service.
  • real-time location system (RTLS) - A real-time location system (RTLS) is one of a number of technologies used to pinpoint the current geographic position and location of a target.
  • regional Bell operating company (RBOC) - Regional Bell operating company (RBOC) is a term describing one of the U.
  • remote access - Remote access is the ability for an authorized person to access a computer or network from a geographical distance through a network connection.
  • remote desktop - A remote desktop is a program or an operating system feature that allows a user to connect to a computer in another location, see that computer's desktop and interact with it as if it were local.
  • Remote Direct Memory Access (RDMA) - Remote Direct Memory Access (RDMA) is a technology that enables two networked computers to exchange data in main memory without relying on the processor, cache or operating system of either computer.
  • remote sensing - Remote sensing is the use of various technologies to make observations and measurements at a target that is usually at a distance or scale beyond those observable to the naked eye.
  • remote terminal unit (RTU) - A remote terminal unit (RTU) is a microprocessor-based electronic device used in an industrial control system (ICS) to connect hardware to a distributed control system (DCS) or supervisory control and data acquisition (SCADA) system.
  • return on marketing investment (ROMI) - Return on marketing investment (ROMI) is a metric used to measure the overall effectiveness of a marketing campaign to help marketers make better decisions about allocating future investments.
  • RFC 1918 - Request for Comment 1918 (RFC 1918), “Address Allocation for Private Internets,” is the Internet Engineering Task Force (IETF) memorandum on methods of assigning of private IP addresses on TCP/IP networks.
  • Rich Internet Application (RIA) - A rich Internet application (RIA) is a Web application designed to deliver the same features and functions normally associated with deskop applications.
  • ROADM (reconfigurable optical add-drop multiplexer) - An ROADM (reconfigurable optical add-drop multiplexer) is a device that can add, block, pass or redirect modulated infrared (IR) and visible light beams of various wavelengths in a fiber optic network.
  • round robin - A round robin is an arrangement of choosing all elements in a group equally in some rational order, usually from the top to the bottom of a list and then starting again at the top of the list and so on.
  • route summarization (route aggregation) - Route summarization -- also known as route aggregation -- is a method to minimize the number of routing tables in an Internet Protocol (IP) network.
  • Routing Information Protocol (RIP) - Routing Information Protocol (RIP) is a distance vector protocol that uses hop count as its primary metric.
  • routing table - A routing table is a set of rules, often viewed in table format, that's used to determine where data packets traveling over an Internet Protocol (IP) network will be directed.
  • RS-232C - RS-232C is one of the earlier versions of the long-established standard RS-232, which defines a physical interface for relatively low-speed serial data communication between computers and related devices.
  • scalable video coding (SVC) - Scalable video coding (SVC) is an extension of the H.
  • SD-branch - SD-branch is a single, automated, centrally managed software-centric platform that replaces or supplements an existing branch network architecture.
  • SDN controller (software-defined networking controller) - A software-defined networking controller is an application in SDN architecture that manages flow control for improved network management and application performance.
  • segment routing - Segment routing is a computer networking process used by networking and traffic engineering professionals that organizes collections of information, or packets, to follow a linear set of instructions.
  • SerDes (serializer/deserializer) - A SerDes or serializer/deserializer is an integrated circuit (IC or chip) transceiver that converts parallel data to serial data and vice-versa.
  • serial digital interface (SDI) - Serial digital interface (SDI) is a standard for digital video and audio transmission over coaxial or fiber optic cabling.
  • serial peripheral interface (SPI) - A serial peripheral interface (SPI) is an interface commonly used in computers and embedded systems to facilitate short-distance communication between a microcontroller and one or more peripheral integrated circuits (ICs).
  • Server Message Block protocol (SMB protocol) - The Server Message Block protocol (SMB protocol) is a client-server communication protocol used for sharing access to files, printers, serial ports and other resources on a network.
  • service chaining - Service chaining, in an information technology (IT) context, is the addition of software-defined networking (SDN) capabilities in a specific sequence.
  • session border controller (SBC) - A session border controller (SBC) is a dedicated hardware device or software application that governs the manner in which phone calls are initiated, conducted and terminated on a voice over Internet Protocol (VoIP) network.
  • session layer - The session layer is Layer 5 of the OSI communications model.
  • Shared Key Authentication (SKA) - Shared Key Authentication (SKA) is a process by which a computer can gain access to a wireless network that uses the Wired Equivalent Privacy (WEP) protocol.
  • shielded twisted pair (STP) - Shielded twisted pair (STP) is a special kind of copper telephone and local area network (LAN) wiring used in some business installations.
  • short message service center (SMSC) - The short message service center (SMSC) is the portion of a mobile phone network that handles text message operations.
  • signal-to-noise ratio (S/N or SNR) - In analog and digital communications, a signal-to-noise ratio, often written S/N or SNR, is a measure of the strength of the desired signal relative to background noise (undesired signal).
  • Signaling System 7 (SS7) - Signaling System 7 (SS7) is an international telecommunication protocol standard that defines how the network elements in a public switched telephone network (PSTN) exchange information and control signals.
  • simplex - Simplex is a communications mode in which only one signal is transmitted, and it always goes in the same direction.
  • Skinny Client Control Protocol (SCCP) - Skinny Client Control Protocol (SCCP) is a Cisco proprietary standard for terminal control for use with voice over IP (VoIP).
  • sliding window (windowing) - The sliding window (windowing) technique is used by Transmission Control Protocol (TCP) to manage the flow of packets between two computers or network hosts.
  • smart home app (home automation app) - A smart home app, sometimes referred to as a home automation app or a smart home automation app, is an application used to remotely control and manage connected non-computing devices in the home, typically from a smartphone or tablet.
  • smart home hub (home automation hub) - A smart home hub is hardware or software that connects devices on a home automation network and controls communications among them.
  • SMS gateway - An SMS gateway is a website that allows users to send SMS messages from a web browser to people within the cell served by that gateway.
  • SNOMED CT (Systematized Nomenclature of Medicine -- Clinical Terms) - SNOMED CT (Systematized Nomenclature of Medicine -- Clinical Terms) is a standardized, multilingual vocabulary of clinical terminology that is used by physicians and other health care providers for the electronic exchange of health information.
  • social networking - Social networks are websites and apps that allow users and organizations to connect, communicate, share information and form relationships.
  • softphone (soft client telephone) - A softphone (software telephone) is an application program that enables voice over Internet Protocol (VoIP) telephone calls from computing devices.
  • software-defined storage (SDS) - Software-defined storage (SDS) is a software program that manages data storage resources and functionality and has no dependencies on the underlying physical storage hardware.
  • Spine-leaf (spine-leaf architecture) - Spine-leaf, or leaf-spine, is a two-layer network topology composed of spine and leaf switches.
  • split horizon - Split horizon is a method used by distance vector protocols to prevent network routing loops.
  • Squid proxy server - Squid is a Unix-based proxy server that caches Internet content closer to a requestor than its original point of origin.
  • standing wave ratio (SWR) - Standing wave ratio (SWR) is the ratio of the maximum magnitude or amplitude of a standing wave to its minimum magnitude.
  • star network - A star network is a local area network (LAN) topology in which all nodes -- personal computers (PCs), workstations or other devices -- are directly connected to a common central computer that is often referred to as a hub.
  • Starlink - Starlink is a satellite internet constellation system that aims to deliver global internet coverage.
  • Stream Control Transmission Protocol (SCTP) - Stream Control Transmission Protocol (SCTP) is a connection-oriented network protocol for transmitting multiple streams of data simultaneously between two endpoints that have established a connection in a network.
  • streaming network telemetry - Streaming network telemetry is a real-time data collection service in which network devices, such as routers, switches and firewalls, continuously push data related to the network's health to a centralized location.
  • subcarrier - A subcarrier is a secondary modulated signal frequency modulated into the main frequency (the carrier) to provide an additional channel of transmission.
  • Switched Multimegabit Data Service (SMDS) - Switched Multimegabit Data Service (SMDS) is a public, packet-switched service aimed at enterprises that need to exchange large amounts of data with other enterprises over the wide area network on a nonconstant or bursty basis.
  • Synchronous Data Link Control (SDLC) - Synchronous Data Link Control (SDLC) is a transmission protocol used to synchronously transfer code-transparent, serial-by-bit data over a communications channel.
  • Synchronous Digital Hierarchy (SDH) - Synchronous Digital Hierarchy (SDH) is a group of fiber optic transmission rates that transport digital signals with different capacities.