ARQ

Automatic repeat request is an error-control method for data transmission. If the sender does not receive an acknowledgment before the timeout, it re-transmits the packet until the sender receives an acknowledgment or exceeds a predefined number of retransmissions.

AAC

Abbreviation of Advanced Audio Coding. A standardized, lossy compression and encoding scheme for digital audio. Designed to be the successor of the MP3 format, AAC generally achieves better sound quality than MP3 at similar bitrates.

AAC-LD

Abbreviation of AAC Low Delay. An audio compression standard designed to combine the advantages of perceptual audio coding with the low delay necessary for two-way communication. It is closely derived from the MPEG-2 Advanced Audio Coding (AAC) standard.

AAC Low Delay

Abbreviated as AAC-LD. An audio compression standard designed to combine the advantages of perceptual audio coding with the low delay necessary for two-way communication. It is closely derived from the MPEG-2 Advanced Audio Coding (AAC) standard.

ABR

Abbreviation of Adaptive Bitrate. Adaptive bitrate streaming is when the system detects fluctuations in the end-users bandwidth and automatically changes the bitrate so the video can continue without buffering.

ABR Cascade

The set of outputs that make up adaptive bitrate groups.

Absolute Domain Name

Absolute domain name, sometimes also referred to as a fully-qualified domain name. A domain name that specifies its exact location in the tree hierarchy of the Domain Name System (DNS).

Active Backup

Only one NIC slave in the bond is active at a time. A different slave becomes active only when the active slave fails. This mode provides fault tolerance.

Active Load Balancing

(ALB). The receive load balancing is achieved by Archive Resolution Protocol (ARP) negotiation. The bonding driver intercepts the ARP replies sent by the server on their way out and overwrites the source hardware address with the unique hardware address of one of the slaves in the bond such that different clients use different hardware addresses for the server.

Adaptive Bitrate

Abbreviated as ABR. Adaptive bitrate streaming is when the system detects fluctuations in the end-users bandwidth and automatically changes the bitrate so the video can continue without buffering.

Advanced Audio Coding

Abbreviated as AAC. A standardized, lossy compression and encoding scheme for digital audio. Designed to be the successor of the MP3 format, Advanced Audio Coding generally achieves better sound quality than MP3 at similar bitrates.

Advanced Encryption Standard

Abbreviated as AES. A specification for the encryption of electronic data established by the U.S. National Institute of Standards.

Advanced Video Coding

Abbreviated as AVC. A standard for video compression, used for the recording, compression, and distribution of high definition video.

AES

Abbreviation of Advanced Encryption Standard. A specification for the encryption of electronic data established by the U.S. National Institute of Standards.

ALB

Active Load Balancing. The receive load balancing is achieved by Archive Resolution Protocol (ARP) negotiation. The bonding driver intercepts the ARP replies sent by the server on their way out and overwrites the source hardware address with the unique hardware address of one of the slaves in the bond such that different clients use different hardware addresses for the server.

Analog

A continuous signal that contains time-varying quantities. Unlike a digital signal which has a discrete value at each sampling point, an analog signal has constant fluctuations. 

Aspect Ratio

The proportion of width to height.

Audio Bitrate

The number of bits used per unit of time to represent an audio stream. Measured in kilobits per second (kbps).

Audio Gain

Measure of the ability of a circuit (often an amplifier) to increase the power or amplitude of a signal from the input to the output, by adding energy to the signal converted from some power supply. Measured in decibels (dB).

Auto-Negotiation

Auto-Negotiation is used to detect the presence of a connection to another device. These "connection present" pulses are sent by Ethernet devices when they are not sending or receiving any frames.

AVC

Abbreviation of Advanced Video Coding. Also known as H.264. A standard for video compression used for the recording, compression, and distribution of high definition video.