| CPC H04W 76/19 (2018.02) [H04L 1/18 (2013.01); H04W 16/24 (2013.01); H04W 76/15 (2018.02); H04W 76/30 (2018.02); H04W 80/02 (2013.01)] | 12 Claims |

|
1. A method performed by a terminal in a wireless communication system, the method comprising:
receiving a radio resource control (RRC) message to change or release a secondary cell group (SCG);
performing a re-establishment for a radio link control (RLC) entity of the terminal based on the RRC message; and
performing a packet data convergence protocol (PDCP) data recovery based on the RRC message,
wherein performing the PDCP data recovery comprises, in case that a PDCP status report is not received:
determining, by a lower layer, whether a successful delivery of PDCP data has been confirmed; and
retransmitting a PDCP protocol data unit (PDU) previously submitted to the re-established RLC entity, for which a successful delivery has not been confirmed by the lower layer,
wherein a PDCP PDU previously submitted, for which a successful delivery has been confirmed by the lower layer, is not retransmitted to the re-established RLC entity.
|