Packet data convergence protocol handling for secondary cell group deactivation
Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may receive, from a base station, a secondary cell group (SCG) deactivation command indicating that an SCG associated with the UE is deactivated. The UE may perform an action associated with a packet data convergence protocol (PDCP) entity and a split radio bearer associated with the SCG based at least in part on receiving the SCG deactivation command. Numerous other aspects are described.
1 . An apparatus for wireless communication at a user equipment (UE), comprising:
memory; and
one or more processors, coupled to the memory, configured to:
receive a secondary cell group (SCG) deactivation command indicating that an SCG associated with the UE is deactivated; and
perform an action associated with a packet data convergence protocol (PDCP) entity and a split radio bearer associated with the SCG based at least in part on receiving the SCG deactivation command, wherein the action includes refraining from reconfiguration of the split radio bearer, ignoring an uplink data split threshold for selecting a cell group to be associated with the split radio bearer before transmitting data associated with the split radio bearer on a master cell group (MCG), and one of:
providing an indication of deactivation of the SCG to the PDCP entity,
providing, from the PDCP entity, one or more PDCP packet data units (PDUs) to an upper layer of the UE,
providing, from the PDCP entity, an indication that particular data associated with the SCG has arrived, or
refraining from providing one or more PDCP PDUs from the PDCP entity to an upper layer of the UE.
2 . The apparatus of claim 1 ,
wherein the action includes providing, from the PDCP entity, the one or more PDCP PDUs to an entity associated with the MCG, and wherein the one or more processors, to perform the action, are configured to:
transmit, via the PDCP entity, data associated with the split radio bearer on the MCG regardless of the uplink data split threshold associated with the split radio bearer.
3 . The apparatus of claim 1 ,
wherein the one or more processors, to perform the action, are configured to:
transmit the one or more PDCP PDUs, that are associated with a first radio link control (RLC) entity that is associated with the SCG, via a second RLC entity that is associated with the MCG.
4 . The apparatus of claim 3 ,
wherein the one or more PDCP PDUs were provided to the first RLC entity via the PDCP entity, and wherein the one or more PDCP PDUs have not been transmitted via the first RLC entity, and wherein the one or more processors, to transmit the one or more PDCP PDUs, are configured to:
transmit, to a base station, the one or more PDCP PDUs, that have not been transmitted via the first RLC entity, via the second RLC entity and the MCG.
5 . The apparatus of claim 3 ,
wherein the one or more PDCP PDUs were provided to the first RLC entity via the PDCP entity, and wherein the one or more PDCP PDUs have been transmitted via the first RLC entity and the SCG and have not been acknowledged by a base station, and wherein the one or more processors, to transmit the one or more PDCP PDUs, are configured to:
transmit, to the base station, the one or more PDCP PDUs that have been transmitted via the first RLC entity but have not been acknowledged by the base station, via the second RLC entity and the MCG.
6 . The apparatus of claim 1 ,
wherein the action includes providing the indication of deactivation of the SCG to the PDCP entity, and wherein the one or more processors, to perform the action, are configured to:
provide, to the PDCP entity and from a medium access control (MAC) entity or from a radio resource control (RRC) entity, the indication of deactivation of the SCG based at least in part on receiving the SCG deactivation command.
7 . The apparatus of claim 1 ,
wherein the action includes refraining from providing the one or more PDCP PDUs from the PDCP entity to the upper layer of the UE, and wherein the one or more processors, to perform the action, are configured to:
refrain, via the PDCP entity, from providing the one or more PDCP PDUs associated with the split radio bearer to a radio link control (RLC) entity associated with the SCG based at least in part on the PDCP entity receiving the indication that the SCG is deactivated.
8 . The apparatus of claim 1 ,
wherein the action includes modifying an amount of time for a timer associated with the PDCP entity, wherein the one or more processors, to perform the action, are configured to:
modify, via the PDCP entity and based at least in part on the SCG being deactivated, the amount of time for the timer, and
wherein the timer is associated with a buffering window for reordering packets associated with the split radio bearer received via the PDCP entity.
9 . The apparatus of claim 8 ,
wherein the one or more processors, to modify the amount of time for the timer, are configured to:
reduce the amount of time associated with the timer.
10 . The apparatus of claim 1 ,
wherein the action includes providing from the PDCP entity, the one or more PDCP PDUs to the upper layer of the UE, and
wherein the one or more processors, to perform the action, are configured to:
provide the one or more PDUs based at least in part on an expiration of a timer associated with a buffering window for reordering packets associated with the split radio bearer received via the PDCP entity.
11 . The apparatus of claim 1 ,
wherein the action includes providing the indication of deactivation of the SCG to the PDCP entity, wherein the one or more processors, to perform the action, are further configured to:
receive, via the PDCP entity, data to be transmitted via a radio bearer associated with the SCG, and
wherein the one or more processors are further configured to:
transmit, to a base station, a buffer status report associated with the radio bearer and the SCG based at least in part on receiving the data to be transmitted via the radio bearer associated with the SCG.
12 . The apparatus of claim 11 ,
wherein the buffer status report is a first buffer status report, and wherein the one or more processors, to transmit the buffer status report associated with the radio bearer and the SCG, are configured to:
transmit, to the base station, a message, via the MCG radio bearer, wherein the message includes the first buffer status report and a second buffer status report associated with the MCG.
13 . The apparatus of claim 11 ,
wherein the one or more processors, to transmit the buffer status report associated with the radio bearer and the SCG, are configured to:
transmit, to the base station, a radio resource control (RRC) message indicating that the data that is associated with the SCG has arrived at the UE.
14 . The apparatus of claim 11 ,
wherein the one or more processors are further configured to:
receive, from the base station, a message to reconfigure the radio bearer to be associated with the MCG or to activate the SCG based at least in part on transmitting the buffer status report associated with the radio bearer and the SCG or based at least in part on transmitting a radio resource control (RRC) message indicating that the data that is associated with the SCG has arrived at the UE.
15 . A method of wireless communication performed by a user equipment (UE), comprising:
receiving a secondary cell group (SCG) deactivation command indicating that an SCG associated with the UE is deactivated; and
performing an action associated with a packet data convergence protocol (PDCP) entity and a split radio bearer associated with the SCG based at least in part on receiving the SCG deactivation command, wherein the action includes refraining from reconfiguration of the split radio bearer, ignoring an uplink data split threshold for selecting a cell group to be associated with the split radio bearer before transmitting data associated with the split radio bearer on a master cell group (MCG), and one of:
providing an indication of deactivation of the SCG to the PDCP entity,
providing, from the PDCP entity, one or more PDCP packet data units (PDUs) to an upper layer of the UE,
providing, from the PDCP entity, an indication that particular data associated with the SCG has arrived, or
refraining from providing one or more PDCP PDUs from the PDCP entity to an upper layer of the UE.
16 . The method of claim 15 ,
wherein the action includes providing, from the PDCP entity, the one or more PDCP PDUs to an entity associated with the MCG, and wherein performing the action comprises:
transmitting, via the PDCP entity, data associated with the split radio bearer on the MCG regardless of the uplink data split threshold associated with the split radio bearer.
17 . The method of claim 15 ,
wherein performing the action comprises:
transmitting the one or more PDCP PDUs, that are associated with a first radio link control (RLC) entity that is associated with the SCG, via a second RLC entity that is associated with the MCG.
18 . The method of claim 17 ,
wherein the one or more PDCP PDUs were provided to the first RLC entity via the PDCP entity, and wherein the one or more PDCP PDUs have not been transmitted via the first RLC entity, and wherein transmitting the one or more PDCP PDUs comprises:
transmitting, to a base station, the one or more PDCP PDUs, that have not been transmitted via the first RLC entity, via the second RLC entity and the MCG.
19 . The method of claim 17 ,
wherein the one or more PDCP PDUs were provided to the first RLC entity via the PDCP entity, and wherein the one or more PDCP PDUs have been transmitted via the first RLC entity and the SCG and have not been acknowledged by a base station, and wherein transmitting the one or more PDCP PDUs comprises:
transmitting, to the base station, the one or more PDCP PDUs that have been transmitted via the first RLC entity but have not been acknowledged by the base station, via the second RLC entity and the MCG.
20 . The method of claim 15 ,
wherein the action includes providing the indication of deactivation of the SCG to the PDCP entity, and wherein performing the action comprises:
providing, to the PDCP entity and from a medium access control (MAC) entity or from a radio resource control (RRC) entity, the indication of deactivation of the SCG based at least in part on receiving the SCG deactivation command.
21 . The method of claim 15 ,
wherein the action includes refraining from providing the one or more PDCP PDUs from the PDCP entity to the upper layer of the UE, and wherein performing the action comprises:
refraining, via the PDCP entity, from providing the one or more PDCP PDUs associated with the split radio bearer to a radio link control (RLC) entity associated with the SCG based at least in part on the PDCP entity receiving the indication that the SCG is deactivated.
22 . The method of claim 15 ,
wherein the action includes modifying an amount of time for a timer associated with the PDCP entity, wherein performing the action comprises:
modifying, via the PDCP entity and based at least in part on the SCG being deactivated, the amount of time for the timer, and
wherein the timer is associated with a buffering window for reordering packets associated with the split radio bearer received via the PDCP entity based at least in part on the SCG being deactivated.
23 . The method of claim 22 ,
wherein modifying the amount of time for the timer comprises:
reducing the amount of time associated with the timer.
24 . The method of claim 15 ,
wherein the action includes providing from the PDCP entity, the one or more PDCP PDUs to the upper layer of the UE, and wherein performing the action comprises:
providing the one or more PDUs based at least in part on an expiration of a timer associated with a buffering window for reordering packets associated with the split radio bearer received via the PDCP entity.
25 . The method of claim 15 ,
wherein the action includes providing the indication of deactivation of the SCG to the PDCP entity, wherein performing the action comprises:
receiving, via the PDCP entity, data to be transmitted via a radio bearer associated with the SCG; and
wherein the method further comprises:
transmitting, to a base station, a buffer status report associated with the radio bearer and the SCG based at least in part on receiving the data to be transmitted via the radio bearer associated with the SCG.
26 . The method of claim 25 ,
wherein the buffer status report is a first buffer status report, and wherein transmitting the buffer status report associated with the radio bearer and the SCG comprises:
transmitting, to the base station, a message, via the MCG radio bearer, wherein the message includes the first buffer status report and a second buffer status report associated with the MCG.
27 . The method of claim 25 ,
wherein transmitting the buffer status report associated with the radio bearer and the SCG comprises:
transmitting, to the base station, a radio resource control (RRC) message indicating that the data that is associated with the SCG has arrived at the UE.
28 . The method of claim 25 , further comprising:
receiving, from the base station, a message to reconfigure the radio bearer to be associated with the MCG or to activate the SCG based at least in part on transmitting the buffer status report associated with the radio bearer and the SCG or based at least in part on transmitting a radio resource control (RRC) message indicating that the data that is associated with the SCG has arrived at the UE.
29 . A non-transitory computer-readable medium storing a set of instructions for wireless communication, the set of instructions comprising:
one or more instructions that, when executed by one or more processors of a user equipment (UE), cause the UE to:
receive a secondary cell group (SCG) deactivation command indicating that an SCG associated with the UE is deactivated; and
perform an action associated with a packet data convergence protocol (PDCP) entity and a split radio bearer associated with the SCG based at least in part on receiving the SCG deactivation command, wherein the action includes refraining from reconfiguration of the split radio bearer, ignoring an uplink data split threshold for selecting a cell group to be associated with the split radio bearer before transmitting data associated with the split radio bearer on a master cell group (MCG), and one of:
providing an indication of deactivation of the SCG to the PDCP entity,
providing, from the PDCP entity, one or more PDCP packet data units (PDUs) to an upper layer of the UE,
providing, from the PDCP entity, an indication that particular data associated with the SCG has arrived, or
refraining from providing one or more PDCP PDUs from the PDCP entity to an upper layer of the UE.
30 . An apparatus for wireless communication, comprising:
means for receiving a secondary cell group (SCG) deactivation command indicating that an SCG associated with the apparatus is deactivated; and
means for performing an action associated with a packet data convergence protocol (PDCP) entity and a split radio bearer associated with the SCG based at least in part on receiving the SCG deactivation command, wherein the action includes refraining from reconfiguration of the split radio bearer, ignoring an uplink data split threshold for selecting a cell group to be associated with the split radio bearer before transmitting data associated with the split radio bearer on a master cell group (MCG), and one of:
providing an indication of deactivation of the SCG to the PDCP entity,
providing, from the PDCP entity, one or more PDCP packet data units (PDUs) to an upper layer of the apparatus,
providing, from the PDCP entity, an indication that particular data associated with the SCG has arrived, or
refraining from providing one or more PDCP PDUs from the PDCP entity to an upper layer of the apparatus.