US 12,231,878 B2
Method and apparatus for performing handover in wireless communication system
Seungbo Yoo, Yongin-si (KR); Daejoong Kim, Yongin-si (KR); Hoon Chang, Seoul (KR); and Namryul Jeon, Seoul (KR)
Assigned to Samsung Electronics Co., Ltd., Suwon-si (KR)
Filed by Samsung Electronics Co., Ltd., Suwon-si (KR)
Filed on Dec. 7, 2023, as Appl. No. 18/532,398.
Application 18/532,398 is a continuation of application No. 17/712,429, filed on Apr. 4, 2022, granted, now 11,843,941.
Application 17/712,429 is a continuation of application No. 16/313,282, granted, now 11,323,874, issued on May 3, 2022, previously published as PCT/KR2017/007292, filed on Jul. 7, 2017.
Claims priority of application No. 10-2016-0087139 (KR), filed on Jul. 8, 2016.
Prior Publication US 2024/0107298 A1, Mar. 28, 2024
This patent is subject to a terminal disclaimer.
Int. Cl. H04W 12/08 (2021.01); H04W 4/00 (2018.01); H04W 12/041 (2021.01); H04W 12/0433 (2021.01); H04W 24/10 (2009.01); H04W 36/00 (2009.01); H04W 36/04 (2009.01); H04W 74/0833 (2024.01); H04W 76/27 (2018.01); H04W 80/02 (2009.01); H04W 80/08 (2009.01)
CPC H04W 12/041 (2021.01) [H04W 12/0433 (2021.01); H04W 24/10 (2013.01); H04W 36/0011 (2013.01); H04W 36/0038 (2013.01); H04W 36/04 (2013.01); H04W 36/13 (2023.05); H04W 74/0833 (2013.01); H04W 76/27 (2018.02); H04W 80/02 (2013.01); H04W 80/08 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method performed by a terminal in a wireless communication system, the method comprising:
receiving, on a source cell, a radio resource control (RRC) reconfiguration message, wherein the RRC reconfiguration message includes:
first information related to a handover from the source cell to a target cell, and
second information indicating whether to change a security key used for the source cell;
performing a random access procedure with the target cell based on the first information; and
transmitting, on the target cell, an RRC reconfiguration complete message after the random access procedure,
wherein, in case that the second information indicates not to change the security key, the security key is used for the target cell after the handover, and
wherein the handover is performed without a change of a packet data convergence protocol (PDCP).