Methods and apparatus to set MRB configuration for UE to receive MBS multicast in RRC inactive state
Apparatus and methods are provided for the UE to receive multicast transmission in RRC INACTIVE state. In one embodiment, the UE joins a multicast session, receives a MRB configuration for a multicast service, establishes an MRB for reception of the multicast service in the RRC INACTIVE state, and receives data transmission of the multicast service with the established MRB in the RRC INACTIVE state. In one embodiment, the UE stores the MRB configuration in the buffer when the multicast session has not started when the MRB configuration is received. In one embodiment, the UE receives a notification for the multicast session start in the RRC INACTIVE state and establishes the MRB based on the stored MRB configuration. In one embodiment, the UE, in the INACTIVE state, updates the multicast resource/MTCH information based on one or more predefined conditions.
1 . A method comprising:
joining, by a user equipment (UE), a multicast session in a wireless network;
receiving a multicast radio bearer (MRB) configuration for a multicast service from the wireless network;
establishing a MRB for reception of the multicast service in a radio resource control (RRC) INACTIVE state based on the MRB configuration;
receiving data transmissions of the multicast service from the wireless network with the established MRB in the RRC INACTIVE state, and
obtaining and updating multicast traffic channel (MTCH) information for the multicast service in the RRC INACTIVE state upon detecting one or more preconfigured conditions.
2 . The method of claim 1 , wherein the MRB configuration is received in a radio resource control (RRC) release message.
3 . The method of claim 2 , wherein the MRB configuration is delivered by suspendconfig in the RRC release message.
4 . The method of claim 1 , further comprising storing the MRB configuration by the UE if the multicast session is not started when the MRB configuration is received.
5 . The method of claim 4 , further comprising:
receiving a notification from the wireless network that the multicast session is started, and wherein the establishing of the MRB involves applying the stored MRB configuration upon receiving the notification.
6 . The method of claim 5 , wherein the notification is a group notification carried in a group paging.
7 . The method of claim 1 , wherein the one or more preconfigured conditions comprises UE moving to another cell in a same RAN-based notification area (RNA), UE updates its interest in the multicast session, a periodic MTCH update and detecting changes of the MTCH information for multicast services.
8 . The method of claim 7 , wherein the UE obtains the MTCH information by sending a RRCResumeRequest to the wireless network.
9 . The method of claim 8 , wherein the RRCResumeRequest includes one or more elements comprising an inactive RNTI (I-RNTI) allocated by a serving cell, and an appropriate cause value.
10 . A method comprising:
receiving, by a network entity, a joining request for a multicast session from a user equipment (UE) in a wireless network;
transmitting, by a network entity of a wireless network, a multicast radio bearer (MRB) configuration to the UE for a multicast service preparing for a multicast reception in a radio resource control (RRC) INACTIVE state for the UE;
transmitting multicast data for the multicast service to the UE in the RRC INACTIVE state; and
updating multicast traffic channel (MTCH) information for the multicast service based on one or more preconfigured conditions, wherein the updated MTCH information is transmitted to at least one UE in the RRC INACTIVE state.
11 . The method of claim 10 , wherein the MRB configuration is transmitted in a radio resource control (RRC) release message.
12 . The method of claim 11 , wherein the MRB configuration is delivered by suspendconfig in the RRC release message.
13 . The method of claim 10 , wherein the network entity updates the MTCH information periodically.
14 . The method of claim 10 , further comprising switching path for the UE to a target cell to receive the multicast data in the RRC INACTIVE state.
15 . A user equipment (UE), comprising:
a transceiver that transmits and receives radio frequency (RF) signal in a wireless network;
a multicast management module that joins a multicast session in the wireless network;
a configuration module that receives a multicast radio bearer (MRB) configuration for a multicast service from the wireless network;
an MRB module that establishes a MRB for reception of the multicast service in a radio resource control (RRC) INACTIVE state based on the MRB configuration; and
a multicast control module that receives data transmissions of the multicast service from the wireless network with the established MRB in the RRC INACTIVE state, and obtains and updates multicast traffic channel (MTCH) information for the multicast service in the RRC INACTIVE state upon detecting one or more preconfigured conditions.
16 . The UE of claim 15 , wherein the MRB configuration is received in a radio resource control (RRC) release message.
17 . The UE of claim 16 , wherein the MRB configuration is delivered by suspendconfig in the RRC release message.
18 . The UE of claim 15 , wherein the configuration module further stores the MRB configuration if the multicast session is not started when the MRB configuration is received.
19 . The UE of claim 18 , wherein the multicast control module further receives a notification from the wireless network that the multicast session is started and applies the stored MRB configuration upon receiving the notification.
20 . The UE of claim 15 , further comprises a multicast update module that obtains and updates multicast traffic channel (MTCH) information for the multicast service in the RRC INACTIVE state upon detecting one or more preconfigured conditions, and wherein the one or more preconfigured conditions comprise UE moving to another cell in a same RAN-based notification area (RNA), UE updates its interest in the multicast session, a periodic MTCH update, and detects changes of the multicast services.