METHOD AND APPARATUS FOR WIRELESS COMMUNICATION

1 . A user equipment (UE) for wireless communication, comprising:

at least one memory; and

at least one processor coupled with the at least one memory and configured to cause the UE to:

communicate with a base station (BS) via a relay node; and

receive, via the relay node from the BS, a radio resource control (RRC) message, wherein the RRC message is one of a first RRC release message, a second RRC release message including a suspend configuration, or an RRC reconfiguration message indicating a remote UE related configuration.

2 . The UE of claim 1 , wherein the at least one processor is configured to cause the UE to:

enter an inactive state in response to receiving the second RRC release message;

initiate a radio access network-based notification area (RNA) update procedure when the UE is in the inactive state;

transmit an RRC resume request in response to initiation of the RNA update procedure; and

receive a notification message or a PC5 release message from the relay node before receiving a response to the RRC resume request.

3 . The UE of claim 2 , wherein:

the notification message indicates a handover of the relay node or a radio link failure (RLF) between the relay node and the BS; and

the at least one processor is configured to, in response to receiving the notification message or the PC5 release message, cause the UE to at least one of set a variable indicating whether there is a pending RNA update procedure or not to true, or start a periodic RNA update timer.

4 . The UE of claim 2 , wherein:

the notification message indicates a connection establishment failure, a handover of the relay node, or a cell reselection at the relay node; and

the at least one processor is configured to, in response to receiving the notification message or the PC5 release message, cause the UE to at least one of set a variable indicating whether there is a pending RNA update procedure or not to true, or start a periodic RNA update timer.

5 . The UE of claim 4 , wherein the notification message or the PC5 release message indicates a time value, which indicates at least one of:

an access barring time at the relay node;

a wait time associated with an access rejection at the relay node;

a value of a timer associated with the handover of the relay node; or

a suggested time for a next transmission to the relay node.

6 . The UE of claim 1 , wherein the at least one processor is configured to cause the UE to:

enter an inactive state in response to receiving the second RRC release message;

initiate a radio access network-based notification area (RNA) update procedure when the UE is in the inactive state;

transmit an RRC resume request in response to initiation of the RNA update procedure; and

detect a radio link failure (RLF) between the UE and the relay node before receiving a response to the RRC resume request.

7 . The UE of claim 6 , wherein the at least one processor is configured to, in response to detecting the RLF, detect a variable indicating whether there is a pending RNA update procedure or not to true, or start a periodic RNA update timer.

8 . The UE of claim 7 , wherein the at least one processor is configured to cause the UE to:

reselect a target relay node or a target cell in response to receiving a notification message or a PC5 release message, or detect the RLF between the UE and the relay node; and

set the variable indicating whether there is a pending RNA update procedure or not to false in response to the RNA update procedure is initiated for a RAN notification area change from a first RAN notification area to a second RAN notification area and a serving cell of the target relay node or the target cell belongs to the first RAN notification area.

9 . The UE of claim 1 , wherein, if the RRC message is the RRC reconfiguration message, the at least one processor is configured to cause the UE to:

receive a notification message from the relay node, wherein the notification message indicates at least one of: a handover of the relay node, a radio link failure (RLF) between the relay node and the BS, a cell reselection at the relay node, or a connection establishment failure at the relay node;

initiate an RRC reestablishment procedure in response to receiving the notification message; and

perform, in response to the initiation of the RRC reestablishment procedure, one of:

starting a selection timer for connection reestablishment;

starting the selection timer for the connection reestablishment in response to determining not to keep a PC5 RRC connection between the UE and the relay node; or

prohibiting the start of the selection timer for the connection reestablishment in response to determining to keep the PC5 RRC connection.

10 . The UE of claim 9 , wherein the at least one processor is configured to cause the UE to:

determine to keep the PC5 RRC connection between the UE and the relay node; and

stop the selection timer for the connection reestablishment in response to determining to keep the PC5 RRC connection.

11 . The UE of claim 9 , wherein the at least one processor is configured to, in response to initiation of the RRC reestablishment procedure or in response to initiation of the RRC reestablishment procedure and a determination of not keeping the PC5 RRC connection, cause the UE to release at least one of the remote UE related configuration, or a dedicated paging delivery configuration for the UE.

12 . The UE of claim 1 , wherein the at least one processor is configured to cause the UE to:

enter an idle state in response to receiving the first RRC release message;

transmit an RRC setup request message for switching from the idle state to a connected state;

start a timer for the RRC setup request message in response to transmission of the RRC setup request message; and

stop the timer for the RRC setup request message in response to at least one of a relay (re)selection at the UE, a cell change due to the relay (re)selection at the UE, or receiving, from the relay node, a notification message or a PC5 release message.

13 . The UE of claim 1 , wherein the at least one processor is configured to cause the UE to suspend or release signaling radio bearers (SRBs) and data radio bearers (DRBs) associated with a link between the UE and the relay node in response to receiving the second RRC release message including the suspend configuration.

14 . A relay node for wireless communication, comprising:

at least one memory; and

at least one processor coupled with the at least one memory and configured to cause the relay node to:

establish a PC5 link between a user equipment (UE) and the relay node, wherein the UE communicates with a base station (BS) via the relay node; and

receive, from the BS, a radio resource control (RRC) reconfiguration message indicating a relay node related configuration associated with the PC5 link between the UE and the relay node.

15 . A method performed by a user equipment (UE), the method comprising:

communicating with a base station (BS) via a relay node; and

receiving, via the relay node from the BS, a radio resource control (RRC) message, wherein the RRC message is one of a first RRC release message, a second RRC release message including a suspend configuration, or an RRC reconfiguration message indicating a remote UE related configuration.

16 . The relay node of claim 14 , wherein the at least one processor is configured to cause the relay node to:

initiate an RRC reestablishment procedure; and

release the relay node related configuration in response to initiation of the RRC reestablishment procedure.

17 . A processor for wireless communication, comprising:

at least one controller coupled with at least one memory and configured to cause the processor to:

communicate with a base station (BS) via a relay node; and

receive, via the relay node from the BS, a radio resource control (RRC) message, wherein the RRC message is one of a first RRC release message, a second RRC release message including a suspend configuration, or an RRC reconfiguration message indicating a remote user equipment (UE) related configuration.

18 . The processor of claim 17 , wherein, if the RRC message is the RRC reconfiguration message, the at least one controller is configured to cause the processor to:

receive a notification message from the relay node, wherein the notification message indicates at least one of a handover of the relay node, a radio link failure (RLF) between the relay node and the BS, a cell reselection at the relay node, or a connection establishment failure at the relay node;

initiate an RRC reestablishment procedure in response to receiving the notification message; and

perform, in response to initiation of the RRC reestablishment procedure, one of:

start a selection timer for connection reestablishment;

start the selection timer for the connection reestablishment in response to determining not to keep a PC5 RRC connection between a UE and the relay node; or

prohibit the start of the selection timer for the connection reestablishment in response to determining to keep the PC5 RRC connection.

19 . The processor of claim 18 , wherein the at least one controller is configured to cause the processor to:

determine to keep the PC5 RRC connection between the UE and the relay node; and

stop the selection timer for the connection reestablishment in response to determining to keep the PC5 RRC connection.

20 . The processor of claim 18 , wherein the at least one controller is configured to, in response to initiation of the RRC reestablishment procedure or in response to initiation of the RRC reestablishment procedure and a determination of not keeping the PC5 RRC connection, cause the processor to release at least one of the remote UE related configuration, or a dedicated paging delivery configuration for a UE.