Section: 16.10.6.7 Shared processing for MBS broadcast and unicast reception
Content: If the UE in RRC_CONNECTED state is receiving or interested to receive an MBS broadcast service from a non-serving cell as described in TS 38.306[ NR; User Equipment (UE) radio access capabilities ]  [11] , the UE may use MBS Interest Indication message to inform the serving gNB about the parameters used for the non-serving cell broadcast reception as described in TS 38.331[ NR; Radio Resource Control (RRC); Protocol specification ]  [12]. The gNB may enable the sending of the MBS Interest Indication by including an indication in SIB1. The UE may indicate to the serving cell the UE capability for receiving MBS broadcast service from a non-serving cell. It is up to gNB implementation to consider the MBS Interest Indication and the UE capability for receiving MBS broadcast service from a non-serving cell, if indicated, when scheduling the UE. In case the UE only reports the frequency for broadcast service reception from the non-serving cell in MBS Interest Indication due to some parameters (e.g., SCS, bandwidth) not being available, the UE may transmit updated MBS Interest Indication once the parameters are available to the UE. It is up to network implementation on how to enable the UE to acquire these parameters from the non-serving cell. 16.10.6.8 Support of Resource Sharing across multiple Broadcast MBS sessions in RAN Sharing Scenario NGAP supports resource sharing efficient scheme for broadcast delivery in RAN sharing. Such scheme enables the gNB to identify broadcast MBS sessions from different PLMNs providing identical content. The identification is based on information provided by the involved 5GCs in the Associated Session ID as specified in TS 23.247[ Architectural enhancements for 5G multicast-broadcast services ]  [45]. If in the MBS Broadcast Setup Request message an Associated Session ID is received from a 5GC participating in RAN sharing, the gNB uses it to determine whether MBS Session resources can be shared with a broadcast MBS session(s) associated with the same Associated Session ID requested from another 5GC participating in RAN sharing. The identification of MBS Broadcast Sessions providing identical content may also be based on implementation specific configuration as specified in TS 23.247[ Architectural enhancements for 5G multicast-broadcast services ]  [45]. The gNB applying this resource efficiency scheme: - may decide whether NG-U resources are established towards all involved 5GCs or only some of them; - resolves different QoS requirements or different S-NSSAIs received from the participating 5GCs in an implementation specific way. The gNB may also trigger the NGAP Broadcast Session Transport procedure towards one 5GC participating in RAN sharing to set up NG-U resources to maintain NG-U connectivity as specified in TS 23.247[ Architectural enhancements for 5G multicast-broadcast services ]  [45].