For duplicating PDCP PDUs for a radio bearer, methods, apparatus, and systems are disclosed. One apparatus 300 includes a processor 305 and a transceiver 325 for communicating with a mobile communication network. The processor 305 establishes 705 a radio bearer to communicate with the network, the radio bearer includes a PDCP entity, first and second RLC entities associated with said PDCP entity, first and second logical channels associated with said first and second RLC entities, respectively. The processor 305 receives 710 a control signal from the network, duplicates 715 PDCP data PDUs in the PDCP entity, and submits 720 them to the first and second RLC entities for transmission. The processor 305 indicates 725 to one of the first and second RLC entities to discard duplicated PDCP data PDUs in response to the successful delivery of corresponding PDCP data PDUs by the other RLC entity.