Automatic Repeat ReQuest(ARQ When the receiver detects errors in a packet, how does it let the transmitter know to re-send the corresponding packet? Systems which automatically request the retransmission of missing packets or packets with errors are called ARQ systems · Three common schemes Stop Wait Go Back n Selective RepeatAutomatic Repeat ReQuest (ARQ) • When the receiver detects errors in a packet, how does it let the transmitter know to re-send the corresponding packet? • Systems which automatically request the retransmission of missing packets or packets with errors are called ARQ systems. • Three common schemes – Stop & Wait – Go Back N – Selective Repeat