Networking and communications

Terms related to networking and communications, including definitions about network protocols and words and phrases about data transmission.
  • 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.
  • 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.
  • 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 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.
  • 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.
  • 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 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.
  • 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).
  • 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.
  • 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.
  • 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.
  • 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.
  • 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.
  • 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.
  • 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.
  • Synchronous Optical Network (SONET) - Synchronous Optical Network (SONET) is a North American standard for synchronous data transmission over optical fibers.
  • team collaboration tools - Team collaboration tools -- also known as team collaboration software -- is a term used to define the different types of software and online services available to companies and individuals that enable them to feasibly work together on common projects, regardless of their physical location.
  • telecommunications (telecom) - Telecommunications, also known as telecom, is the exchange of information over significant distances by electronic means and refers to all types of voice, data and video transmission.
  • teleconference - A teleconference is a live audio or audio-visual meeting with two or more participants.
  • telegraph - A telegraph is a communication system that sends information by making and breaking an electrical connection.
  • telematics - Telematics is a term that combines the words telecommunications and informatics to describe the use of communications and IT to transmit, store and receive information from devices to remote objects over a network.
  • telemetry - Telemetry is the automatic measurement and wireless transmission of data from remote sources.
  • Time Division Multiple Access (TDMA) - Time Division Multiple Access (TDMA) is a digital modulation technique used in digital cellular telephone and mobile radio communication.
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  • Transmission Control Protocol (TCP) - Transmission Control Protocol (TCP) is a standard protocol on the internet that ensures the reliable transmission of data between devices on a network.
  • transport layer - The transport layer is Layer 4 of the Open Systems Interconnection (OSI) communications model.
  • trunk (trunking) - A network trunk is a communications line or link designed to carry multiple signals simultaneously to provide network access between two points.
  • unified communications (UC) - Unified communications (UC) is an umbrella term for the integration of multiple enterprise communication tools -- such as voice calling, video conferencing, instant messaging (IM), presence and content sharing -- into a single, streamlined interface, with the goal of improving user experience (UX) and productivity.
  • unified communications and collaboration (UCC) - Unified communications and collaboration (UCC) is the collection of technology and software that combines enterprise communication with real-time and asynchronous cooperation capabilities.
  • uplink and downlink - In satellite telecommunication, a downlink is the link from a satellite down to one or more ground stations or receivers, and an uplink is the link from a ground station up to a satellite.
  • USART (universal synchronous/asynchronous receiver/transmitter) - A USART (universal synchronous/asynchronous receiver/transmitter) is hardware that enables a device to communicate using serial protocols.
  • Variable Length Subnet Mask (VLSM) - Variable Length Subnet Mask (VLSM) is a subnet -- a segmented piece of a larger network -- design strategy where all subnet masks can have varying sizes.
  • video streaming service - A video streaming service is an on-demand online entertainment source for TV shows, movies and other streaming media.
  • virtual switch (vSwitch) - A virtual switch (vSwitch) is a software program that enables one virtual machine (VM) to communicate with another.
  • vishing (voice or VoIP phishing) - Vishing (voice or VoIP phishing) is a type of cyber attack that uses voice and telephony technologies to trick targeted individuals into revealing sensitive data to unauthorized entities.
  • VLAN (virtual LAN) - A virtual LAN (VLAN) is a logical overlay network that groups together a subset of devices that share a physical LAN, isolating the traffic for each group.
  • VMware - VMware is a virtualization and cloud computing software provider based in Palo Alto, Calif.
  • voice over LTE (VoLTE) - Voice over LTE (VoLTE) is a digital packet technology that uses 4G LTE networks to route voice traffic and transmit data.
  • VoIP phone - A VoIP phone is a hardware- or software-based telephone designed to use voice over Internet Protocol (VoIP) technology to send and receive phone calls over an IP network.
  • von Neumann bottleneck - The von Neumann bottleneck is a limitation on throughput caused by the standard personal computer architecture.
  • WAN (wide area network) - A wide area network (WAN) is a geographically distributed private telecommunications network that interconnects multiple local area networks (LANs).
  • WAN optimization (WAN acceleration) - WAN optimization -- also known as WAN acceleration -- is a collection of technologies and techniques used to improve the efficiency of data transfer across a wide area network (WAN) between organizations' centralized data centers and their remote locations.
  • wave number - A wave number, or wavenumber, refers to the spatial frequency of a wave over a specific unit distance.
  • WebSocket - WebSocket is a communications protocol that enables two endpoints -- typically a client and a server -- to establish a persistent, bidirectional, full duplex TCP connection between them.
  • What is a checksum? - A checksum is a value that represents the number of bits in a transmission message.
  • What is a MAC address and how do I find it? - A MAC address (media access control address) is a 12-digit hexadecimal number assigned to each device connected to the network.
  • What is a network node? - A network node is a connection point in a communications network.
  • What is a network packet? - A network packet is a basic unit of data that is transferred over a computer network, typically a packet-switched network, such as the internet.
  • What is a private cloud? Definition and examples - Private cloud is a type of cloud computing that delivers advantages similar to public cloud, including scalability and self-service, but through a proprietary architecture.
  • What is a programmable network (network programmability)? - A programmable network is one in which software that operates independently of network hardware handles the behavior of network devices and flow control.
  • What is a remote desktop and how does it work? - 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.
  • What is a Request for Comments (RFC)? - A Request for Comments (RFC) is a formal document created by the Internet Engineering Task Force (IETF) that outlines technical specifications, organizational notes and standards relevant to internet and networking technologies, including protocols such as routing, addressing and transport technologies.
  • What is a server? - A server is a computer program or device that provides a service to another computer program and its user, also known as the client.
  • What is a service mesh? - A service mesh is a dedicated infrastructure layer that controls service-to-service communication within a distributed application.
  • What is a software-defined data center (SDDC)? - A software-defined data center (SDDC) is a server management concept in which all infrastructure elements -- networking, storage and compute -- are virtualized and delivered as a service.
  • What is a wireless mesh network (mesh WiFi)? - A wireless mesh network (WMN) is a mesh network created through the connection of wireless access point (wireless AP) nodes installed at each network user's location.
  • What is an initialization vector? - An initialization vector (IV) is an arbitrary number that can be used with a secret key for data encryption to foil cyber attacks.
  • What is asynchronous? - In general, asynchronous -- from Greek asyn- ('not with/together') and chronos ('time') -- describes objects or events not coordinated in time.
  • What is Border Gateway Protocol (BGP)? - BGP (Border Gateway Protocol) is the protocol that enables the internet's global routing system.
  • What is Cisco Certified Internetwork Expert (CCIE) certification? - Cisco Certified Internetwork Expert (CCIE) certification is a series of technical certifications for senior networking professionals who design, build, implement, maintain and troubleshoot complex enterprise networking infrastructures.
  • What is Cisco Performance Routing (PfR)? - Cisco Performance Routing (PfR) is a way of sending network packets based on intelligent path control.
  • What is cloud computing? Types, examples and benefits - Cloud computing is a general term for the on-demand delivery of hosted computing and IT services over the internet with pay-as-you-go pricing.
  • What is cloud networking? - Cloud networking is a type of IT infrastructure in which the cloud hosts some or all of an organization's networking resources.
  • What is data center interconnect (DCI)? - Data center interconnect (DCI) technology links two or more data centers so they can share resources.
  • What is DHCP (Dynamic Host Configuration Protocol)? - DHCP (Dynamic Host Configuration Protocol) is a network management protocol used to dynamically assign an Internet Protocol (IP) address to any device on a network so it can communicate.
  • What is east-west traffic? - East-west traffic refers to the transfer of data packets that move from server to server within a network's data center.
  • What is edge computing? Everything you need to know - Edge computing is a distributed information technology (IT) architecture in which client data is processed at the periphery of the network, as close to the originating source as possible.
  • What is EM shielding (electromagnetic shielding)? - EM shielding (electromagnetic shielding) is the practice of surrounding electronics and cables with conductive or magnetic materials to guard against incoming or outgoing emissions of electromagnetic frequencies (EMF).
  • What is FCAPS (fault, configuration, accounting, performance and security)? - FCAPS (fault, configuration, accounting, performance and security) is a network management framework and model created by the International Organization for Standardization (ISO).
  • What is fog computing? - Fog computing is a decentralized computing infrastructure in which data, compute, storage and applications are located somewhere between the data source and the cloud.
  • What is FTP? - File Transfer Protocol (FTP) is a network protocol for transmitting files between computers over TCP/IP connections.
  • What is HTTP and how does it work? Hypertext Transfer Protocol - HTTP (Hypertext Transfer Protocol) is the set of rules for transferring files -- such as text, images, sound, video and other multimedia files -- over the web.
  • What is IMAP (Internet Message Access Protocol)? - IMAP (Internet Message Access Protocol) is a standard retrieval protocol for receiving email.
  • What is Internet Key Exchange (IKE)? - Internet Key Exchange (IKE) is a standard protocol used to set up a secure and authenticated communication channel between two parties via a virtual private network (VPN).