Go-Back-N is a type of automatic repeat request (ARQ) protocol used in computer networks for reliable data transmission. It allows a sender to send multiple frames before needing an acknowledgment for the first one, but it can only send frames up to a specified window size. If an error occurs, the sender must go back and retransmit all frames from the erroneous one onward. This protocol is efficient for managing data flow and reducing delays in communication. However, it can lead to inefficiencies if many frames need to be resent, especially in high-error environments, as it requires retransmitting all subsequent frames after a lost or corrupted one.