Unified Communications Definitions

This glossary explains the meaning of key words and phrases that information technology (IT) and business professionals use when discussing unified communications and related software products. You can find additional definitions by visiting WhatIs.com or using the search box below.

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  • #

    4K video resolution

    4K video resolution is high-definition (HD) video that has four times the resolution of 1080p HD video.

  • A

    analog telephone adapter (ATA)

    An analog telephone adapter (ATA) is a device used to connect an analog telephone, fax machine or similar equipment to a computer or network to enable communications over the internet.

  • Avaya

    Avaya is an American technology company that specializes in business communications services, such as unified communications (UC) and contact center (CC).

  • B

    bring your own carrier (BYOC)

    Bring your own carrier (BYOC) is a method of letting businesses choose their own carrier to connect their unified communications provider to the public switched telephone network.

  • C

    call admission control (CAC)

    Call admission control (CAC) is the practice or process of regulating traffic volume in voice communications, particularly in wireless mobile networks and in VoIP (voice over Internet Protocol, also known as Internet telephony)... (Continued)

  • call control

    Call control is a process that is used in telecommunications networks to monitor and maintain connections once they have been established.

  • call deflection

    Call deflection is a feature of voice over IP (VoIP) that automatically redirects a call from the called endpoint to another endpoint (usually a voice mailbox) when the called endpoint is busy.

  • call detail record (CDR)

    A call detail record (CDR) in voice over IP (VoIP) is a file containing information about recent system usage such as the identities of sources (points of origin), the identities of destinations (endpoints), the duration of each call, the amount billed for each call, the total usage time in the billing period, the total free time remaining in the billing period, and the running total charged during the billing period.

  • call signaling

    Call signaling is a process that is used to set up a connection in a telephone network.

  • centrex (central office exchange service)

    Centrex (central office exchange service) is a service from local telephone companies in the United States in which up-to-date phone facilities at the phone company's central (local) office are offered to business users so that they don't need to purchase their own facilities.

  • Cisco Webex

    Cisco Webex is a video conferencing and collaboration product suite.

  • CLEC (competitive local exchange carrier)

    In the United States, a CLEC (competitive local exchange carrier) is a telephone company that competes with the already established local telephone business by providing its own network and switching.

  • cloud PBX (private branch exchange)

    A cloud PBX (private branch exchange) is a business phone system for connecting employees to a telephone network using a managed service running in the cloud.

  • cloud telephony (cloud calling)

    Cloud telephony (cloud calling) is a type of unified communications as a service (UCaaS) that offers voice communication services through a third-party host.

  • codec

    A codec is a hardware- or software-based process that compresses and decompresses large amounts of data.

  • communications platform as a service (CPaaS)

    Communications platform as a service (CPaaS) is a cloud-based delivery model that allows organizations to add real-time communication capabilities, such as voice, video and messaging, to business applications by deploying application program interfaces (APIs).

  • D

    data transfer rate (DTR)

    The data transfer rate (DTR) is the amount of digital data that's moved from one place to another in a given time.

  • dedicated line

    A dedicated line is a telecommunications path between two points that is available 24 hours a day for use by a designated user (individual or company).

  • E

    E911 (Enhanced 911)

    In the United States, E911 (Enhanced 91 is support for wireless phone users who dial 911, the standard number for requesting help in an emergency.

  • eavesdropping

    Eavesdropping is the act of listening to, recording or intercepting private communications.

  • Erlang B

    Erlang B is a modeling formula that is widely used in call center scheduling... (Continued)

  • Erlang C

    Erlang C is a traffic modeling formula, primarily used in call center scheduling to calculate delays and to predict waiting times for callers.

  • Ethernet/IP (Ethernet Industrial Protocol)

    Ethernet/IP (Ethernet Industrial Protocol) is a network communication standard capable of handling large amounts of data at speeds of 10 Mbps or 100 Mbps, and at up to 1500 bytes per packet.

  • G

    greenfield deployment

    A greenfield deployment is the design, installation and configuration of computer infrastructure where none existed before, for example, in a new office.

  • What is a H.323 gatekeeper?

    A gatekeeper is a management tool for H.323 multimedia networks.

  • H

    hairpinning

    In general telecommunication, hairpinning is returning a message from an origin endpoint back in the direction it came from as a way to get it to its destination endpoint.

  • hop off

    Hop off is a term used in telecommunications that refers to a point at which a signal or call leaves a network and moves to another network.

  • I

    incumbent local exchange carrier (ILEC)

    An incumbent local exchange carrier (ILEC) is a type of U.S. telephone company that provided local service when the Telecommunications Act of 1996 was enacted.

  • Indefeasible Right of Use (IRU)

    In telecommunications, the Indefeasible Right of Use (IRU) is a contractual agreement (temporary ownership) of a portion of the capacity of an international cable.

  • instant messaging

    Instant messaging, often shortened to IM or IM'ing, is the exchange of near real-time messages through a standalone application or embedded software.

  • Internet Protocol (IP)

    The Internet Protocol (IP) is the method or protocol by which data is sent from one computer to another on the internet.

  • IP PBX (private branch exchange)

    An IP PBX is a private branch exchange (telephone switching system within an enterprise) that switches calls between VoIP (voice over Internet Protocol or IP) users on local lines while allowing all users to share a certain number of external phone lines.

  • IP telephony (Internet Protocol telephony)

    IP telephony (Internet Protocol telephony) is a general term for technologies, products and services that use the Internet Protocol's packet-switched connections to support voice calling, voicemail, video calling, video conferencing, faxing and instant messaging.

  • What is an inbound call?

    An inbound call is typically initiated by a customer to a call center or contact center.

  • J

    jitter

    Jitter is any deviation in, or displacement of, the signal pulses in a high-frequency digital signal.

  • jitter buffer

    In voice over IP (VoIP), a jitter buffer is a shared data area where voice packets can be collected, stored, and sent to the voice processor in evenly spaced intervals.

  • L

    leased line

    A leased line is a bidirectional telephone line that has been rented for private voice, data exchange or telecommunication use.

  • M

    Microsoft Teams

    Microsoft Teams is cloud-based team collaboration software that offers core capabilities, including business messaging, calling, video meetings and file sharing.

  • P

    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.

  • What is podcasting?

    Podcasting is the preparation and distribution of digital audio files to the computers of subscribed users using Really Simple Syndication (RSS) feeds.

  • Q

    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.

  • R

    real-time application (RTA)

    A real-time application is an application program that functions within a time frame that the user senses as immediate or current.

  • real-time communications (RTC)

    Real-time communications (RTC) is any mode of telecommunications in which all users can exchange information instantly or with negligible latency or transmission delays.

  • regional Bell operating company (RBOC)

    Regional Bell operating company (RBOC) is a term describing one of the U.S. regional telephone companies (or their successors) that were created as a result of the breakup of American Telephone and Telegraph Company (AT&T, known also as the Bell System or "Ma Bell") by a U.S. Federal Court consent decree on December 31, 1983. The seven original regional Bell operating companies were Ameritech, Bell Atlantic, BellSouth, NYNEX, Pacific Bell, Southwestern Bell, and US WEST. Each of these companies owned at least two Bell operating companies (Bell operating company).

  • rich presence technology (RPT)

    Rich presence is an enhanced form of presence awareness in which participants can determine if other users are online and if so, observe to a limited extent what they are doing and how they are doing it... (Continued)

  • What is Real-Time Transport Control Protocol (RTCP)?

    Real-Time Transport Control Protocol (RTCP) is a network communication protocol that works alongside Real-Time Protocol (RTP) to monitor and track data delivery on large multicast networks via RTP's associated transmission metrics.

  • S

    scalable video coding (SVC)

    Scalable video coding (SVC) is an extension of the H.264 (MPEG-4 AVC) video compression standard for video encoding.

  • SDP (Session Description Protocol)

    SDP (Session Description Protocol) is a set of rules that defines how multimedia sessions can be set up to allow all end points to effectively participate in the session. In this context, a session consists of a set of communications end points along with a series of interactions among them... (Continued)

  • Session Initiation Protocol (SIP)

    Session Initiation Protocol (SIP) is a signaling protocol used for initiating, maintaining, modifying and terminating real-time sessions that involve video, voice, messaging and other communications applications and services between two or more endpoints on IP networks.

  • 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).

  • softphone (soft client telephone)

    A softphone (software telephone) is an application program that enables voice over Internet Protocol (VoIP) telephone calls from computing devices. In the enterprise, softphones are sometimes referred to as soft clients.

  • What is SIP trunking (Session Initiation Protocol trunking)?

    Session Initiation Protocol (SIP) trunking is a service a communications service provider offers that uses the protocol to provision voice over IP (VoIP) and multimedia connectivity between an on-premises phone system and the public switched telephone network (PSTN).

  • What is speech technology?

    Speech technology is a type of computing technology that enables an electronic device to recognize, analyze and understand spoken word or audio.

  • T

    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.

  • 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.

  • What is telephony?

    Telephony is technology associated with interactive communication between two or more physically distant parties using the electronic transmission of data.

  • U

    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.

  • What is UCaaS? Unified communications as a service guide

    Unified communications as a service (UCaaS) is a cloud delivery model that offers a variety of communication and collaboration applications and services.

  • V

    video conferencing

    Video conferencing is live, visual connection between two or more remote parties over the internet that simulates a face-to-face meeting.

  • video streaming

    Video streaming is a continuous transmission of video files from a server to a client.

  • virtual phone number

    A virtual phone number is a telephone number is used to route calls to the user's actual phone number or numbers.

  • 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.

  • VoIP caller ID (voice over Internet Protocol caller identification)

    VoIP caller ID (voice over Internet Protocol caller identification) is a caller ID application for VoIP phones that works in the same way as caller ID on a conventional telephone line.

  • 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.

  • Vonage

    Vonage is a communication platform as a service (CPaaS) provider for consumers and businesses that makes it possible for customers to connect and communicate on any device through cloud-hosted voice, video, chat and short message service (SMS).

  • What is a virtual contact center?

    A virtual contact center (VCC) is a type of call center in which an organization's representatives are geographically dispersed, rather than situated at workstations in one location.

  • What is VoIP (voice over Internet Protocol)?

    VoIP (voice over Internet Protocol) is the transmission of voice and multimedia content over an internet connection.

  • W

    WebRTC (Web Real-Time Communications)

    WebRTC (Web Real-Time Communications) is an open source project that enables real-time voice, text and video communications capabilities between web browsers and devices.