Configuring an adaptation layer in a relay node communicates with a central unit of a donor base station through a distributed unit of the donor base station comprises connecting to the donor base station, after establishing the connection, configuring an adaptation layer in a protocol stack for an MT part of the relay node, the adaptation layer providing for routing of incoming packets to one or more further relay nodes or to one or more user equipments, UEs, connected to the relay node and for mapping of those incoming packets to bearers, and, after configuring the adaptation layer for the MT part of the relay node, configuring an adaptation layer for the distributed unit part of the relay node for forwarding packets exchanged between the central unit of the donor base station and the first further relay node downstream of the relay node.