New methods and devices for implementing an ARQ mechanism over a multi-hop connection (sender-relay-receiver) are proposed. A communication protocol is described in accordance with which data units are arranged in a sequence and each sent data unit is identifiable by a sequence position identifier. The sender implements a sending peer, the relay a relay peer and the receiver a receiving peer. Feedback messages are exchanged, which using said sequence position identifiers, carry information on a receipt of sent data units. The communication protocol provides for at least a first type and a second type of receipt information, the first type (RACK) of receipt information being indicative of a correct receipt of a data unit at a relay peer of said communication protocol, and the second type (ACK) of receipt information being indicative of a correct receipt of a data unit at a final destination peer of said communication protocol.