ARQ

ARQ is an acronym for Automatic Repeat-reQuest. It is an Error control method for data transmission in which the receiver detects transmission errors in a message and automatically requests a retransmission from the transmitter.

Usually, when the transmitter receives the ARQ, the transmitter retransmits the message until it is either correctly received or the error persists beyond a predetermined number of retransmissions.

Few types of ARQ protocols are Stop-and-wait ARQ, Go-Back-N ARQ and Selective Repeat ARQ.