Glossary

Agora Analytics is a site for developers to track and analyze the usage and quality of calls.

Agora Cloud Backup is a backup cloud storage service used in cloud recording. If the recording service cannot upload the recorded files to the specified third-party cloud storage, then the service automatically and temporarily stores them in the backup cloud.

Agora Console is a site for developers to manage Agora projects and services.

An app ID is a randomly generated string provided by Agora and is the unique identifier of an app.

An app certificate is a randomly generated string provided by Agora for enabling token authentication. It is one of the required arguments for generating a token.

The audience are users who do not have streaming permissions in the channel. The audience can only subscribe to the remote audio and video streams, but cannot publish the audio and video streams. For more information, see user role.

Becoming an audience describes a scenario within an Interactive Live Streaming channel (the channel profile is Live-Broadcast) when a host switches the user role and becomes an audience.

Audio mixing means combining multiple audio streams into one.

An audio profile includes the sample rate, encoding scheme, number of channels, and bitrate for encoded audio data.

The audio route is the pathway audio data takes through audio hardware components during playback.

A callee is a Signaling user who receives a call invitation.

A caller is an Signaling user who sends a call invitation.

Call invitation is a communication protocol based on the peer-to-peer messaging functionality of the Agora Signaling SDK. Call invitation supports starting, ending, accepting, and refusing calls.

A channel is created by a developer calling the methods provided by Agora for transmitting real-time data.

Channel attributes are tags added to Signaling channels, including the property name, property value, the ID of the last Signaling user who updated the attribute, and the time of the last update.

A channel message is a message that a Signaling user sends to all Signaling users in a channel.

The channel profile is a configuration that Agora uses to apply optimized algorithms for different real-time scenarios.

Cloud Proxy is a proxy service that enables users to connect to Agora services through a firewall by using fixed IP addresses.

Cloud Recording is a component provided by Agora for recording and saving voice and video calls and interactive streaming on a third-party cloud storage through RESTful APIs.

Co-hosting describes a scenario with more than one host.

Composite recording mode generates a single mixed audio and video file for all UIDs in a channel.

Custom rendering is the process where developers collect raw data from the SDK and process it according to specific needs.

Custom source is the process where an app captures raw data by itself.

In real-time audio and video communication, delay refers to the time elapsed from when the data is sent to when it is received.

In the dual-stream mode, the Video SDK simultaneously transmits a higher-resolution video stream along with an additional low-resolution, low bitrate video stream.

Freeze refers to choppy audio or video playback caused by a poor network connection or limited device performance during real-time audio and video communication.

In dual-stream mode, the SDK transmits two video streams of differing quality at the same time. See dual stream mode for details.

The host refers to a user who has streaming permissions in the channel.

Becoming a host describes a scenario within an Interactive Live Streaming channel (the channel profile is Live-Broadcast) when an audience switches the user role and becomes a host.

Individual recording mode records audio and video of each UID as separate files.

Inject online media stream refers to injecting an online media stream in an Interactive Live Streaming channel to share the stream with all users in the channel. The Agora Video SDK provides a method for developers to inject an online mixed audio and video stream or an audio only stream to a channel.

Enabled by either Agora’s Video SDK or Voice SDK, Interactive Live Streaming gives you full control over the streaming experience from a standard one-to-many stream to a highly-interactive live event.

In real-time audio and video communication, jitter is the variation in the delay of data packets transmitted continuously on the network.

The last mile refers to the network between the Agora edge server and the end user's device.

A loopback test sends a signal from a communication device and is then returned (looped back) to it. It is often used to determine whether a device is working properly.

In dual-stream mode, the SDK transmits two video streams of differing quality at the same time. The low-quality video stream has a lower resolution and bitrate than the high-quality video stream. See dual stream mode for details.

The mediaplayer kit is a plug-in of the Video SDK to play local and online media resources and publish the media streams to other users in an Interactive Live Streaming channel.

A media stream is an object that contains media data.

Media Push enables you to upload audio and video streams from Agora channels and upload them to a Content Delivery Network (CDN) to reach a larger audience.

Mirroring is an effect that a video image renders.

Offline describes the status of an Signaling user who has successfully logged out of Signaling.

An offline message is a peer-to-peer message that an online Signaling user sends to an offline Signaling user.

Online describes the status of a user who has successfully logged in to the Agora Signaling system or stays disconnected from the Agora Signaling system for more than 30 seconds.

On-Premise Recording is a component provided by Agora for recording and saving voice and video calls and interactive streaming on a Linux server.

Packet loss refers to the data packets transmitted on the network failing to arrive at their intended destination.

A peer-to-peer message is a message that an online Signaling user sends to an online or offline user.

Publishing is the action of sending the user's audio and/or video data to the channel.

Raw data, including raw audio data and raw video data, is the unprocessed data which developers can collect during real-time communication.

Rendering the first video frame is the action of rendering the first video frame on the local device.

Agora SD-RTN™, or Software Defined Real-time Network, is a real-time transmission network built by Agora and is the only network infrastructure specifically designed for real-time communications in the world.

You use the Signaling SDK to implement real-time messaging scenarios that require low latency and high concurrency for a global audience.

Slicing means cutting recorded audio or video into separate files according to specific rules. During an Agora Cloud Recording, the recording service cuts the streams and generates multiple slice files (TS or WebM files) and M3U8 files that serve as a playlist of the slice files.

Sound localization means determining the distance to and direction of a sound through hearing the difference of volume, time, and timbre between users' ears.

In scenarios where multiple users engage in real-time audio and video communication, user experience can be impaired if the network condition is too poor to guarantee both audio and video at the same time.

Stream mixing means combining multiple media streams into one. It may include the mixing of video streams (video mixing) and audio streams (audio mixing).

In the Agora Video SDK, subscribing is the action of receiving media streams published to the channel. In the Agora Signaling SDK, subscribing is the action of monitoring the online status of one or multiple Signaling users.

TCP (Transmission Control Protocol) is a connection-oriented and reliable transport layer communication protocol.

A token, also known as a dynamic key, is used for authentication when an app user joins an channel or logs onto the Agora Signaling.

Transcoding is the process of decoding audio and video data and then re-encoding them into the target conversion output or format.

UDP (User Datagram Protocol) is a connectionless-oriented and unreliable transport layer communication protocol.

User attributes are tags added to Signaling users, including property names and property values.

In the Agora Video SDK, a user ID identifies a user in the channel. In the Agora Signaling SDK, a user ID identifiers a user in Signaling. The user ID in the Agora Video SDK and the Agora Signaling SDK are independent of each other.

The type of user role determines whether the user in the channel has streaming permissions.

Video layout arranges the display of users when multiple users are mixed into one stream, such as in Media Push or a composite recording.

Video mixing means combining multiple video streams into one.

The video profile refers to a set of video attributes, such as resolution, bitrate, and frame rate.

Agora provides the Video SDK to enable real-time audio and video communication.

Agora provides the Voice SDK to enable real-time audio communication.

In web page recording mode, the content and audio of a specified web page are recorded in a single file.