Methods and radio network nodes for handling communication
Embodiments herein relate to, for example, a method performed by a source radio network node ( 140 ), for handling communication in a wireless communications network, wherein the source radio network node is adapted to relay data packets between a first radio network node and a UE in the wireless communications network. The source radio network node ( 140 ) transmits to a target radio network node ( 150,12,15 ) a message relating to a cell selection and/or a handover for the UE, wherein the message comprises a first user plane indication, and wherein the first user plane indication is an indication of setting up a user plane communication or not for the UE.
1. A method performed by source radio network node adapted to relay data packets between a first radio network node and a user equipment (UE) in a wireless communications network, the method comprising:
transmitting, to a target radio network node in the wireless communications network, a message relating to a cell selection and/or a handover for the UE, wherein the message comprises a first user plane indication indicating whether or not user plane communication should be setup for the UE.
2. The method according to claim 1 , wherein the target radio network node comprises a third radio network node, the first radio network node, or an intermediate radio network node.
3. The method according to claim 1 , wherein the message is part of one of the following:
Handover Resource Allocation and Initial Context Setup procedure in S1 application protocol;
Handover Preparation and Handover Resource Allocation procedure in NG application protocol;
at least one of the following procedures in X2 application protocol: Handover Preparation, Secondary NodeB Addition Preparation, Retrieve UE Context, and Secondary gNB Addition Preparation; or
Handover Preparation and Secondary-NG-radio access network node Addition Preparation procedure in Xn application protocol.
4. The method according to claim 1 , wherein the first user plane indication comprises one or more of the following, which indicates that a user plane communication should not be setup for the UE: a value not in a range of values defined by 3GPP; a protocol data unit (PDU) Session ID; an E-UTRAN Radio Access Bearer (E-RAB) ID; a data radio bearer (DRB) ID.
5. The method according to claim 1 , wherein:
the first user plane indication comprises a first user plane setup parameter; and
when first user plane setup parameter indicates that user plane communication should not be setup for the UE, the first user plane setup parameter further indicates that other user plane setup parameters of the message should be ignored irrespective of their values.
6. The method according to claim 1 , wherein:
the message is a HANDOVER REQUEST XnAP message, and
the first user plane indication comprises a protocol data unit (PDU) Session ID value indicating that a PDU Session Resources To Be Setup List should be ignored by the target radio network node.
7. The method according to claim 1 , wherein:
the message is a HANDOVER REQUEST XnAP message, and
the first user plane indication comprises an information element indicating whether or not a protocol data unit (PDU) Session Resources To Be Setup List should be ignored by the target radio network node.
8. The method according to claim 1 , wherein transmitting the message to the target radio network node is responsive to determining one or more of the following based on a cell indication obtained from the UE or from another radio network node: to handover the UE to the target radio network node, and to add a secondary cell for the UE.
9. A method performed by a target radio network node arranged to handle communication in a wireless communications network that comprises a source radio network node arranged to relay data packets between a first radio network node and a user equipment (UE), the method comprising:
receiving from the source radio network node or the first radio network node a message relating to a cell selection or a handover for the UE, wherein the message comprises a first user plane indication indicating whether or not user plane communication should be setup for the UE; and
performing a setup of a connection for the UE based on the first user plane indication.
10. The method according to claim 9 , wherein performing the setup of a connection for the UE based on the first user plane indication comprises refraining from setup of user plane communication for the UE when the first user plane indication indicates that user plane communication should not be setup for the UE.
11. The method according to claim 10 , wherein refraining from setup of user plane communication for the UE comprises ignoring information in the message that relates to user plane resources.
12. The method according to claim 9 , wherein the target radio network node comprises one of the following: an integrated access backhaul (IAB) donor node, or an intermediate radio network node.
13. The method according to claim 9 , wherein the message is part of one of the following:
Handover Resource Allocation and Initial Context Setup procedure in S1 application protocol;
Handover Preparation and Handover Resource Allocation procedure in NG application protocol;
at least one of the following procedures in X2 application protocol: Handover Preparation, Secondary NodeB Addition Preparation, Retrieve UE Context, and Secondary gNB Addition Preparation; or
Handover Preparation and Secondary-NG-radio access network node Addition Preparation procedure in Xn application protocol.
14. The method according to claim 9 , wherein the first user plane indication comprises one or more of the following, which indicates that a user plane communication should not be setup for the UE: a value not in a range of values defined by 3GPP; a protocol data unit (PDU) Session ID; an E-UTRAN Radio Access Bearer (E-RAB) ID; a data radio bearer (DRB) ID.
15. The method according to claim 9 , wherein:
the first user plane indication comprises a first user plane setup parameter; and
when first user plane setup parameter indicates that user plane communication should not be setup for the UE, the first user plane setup parameter further indicates that other user plane setup parameters of the message should be ignored irrespective of their values.
16. The method according to claim 9 , wherein:
the message is a HANDOVER REQUEST XnAP message, and
the first user plane indication comprises a protocol data unit (PDU) Session ID value indicating that a PDU Session Resources To Be Setup List should be ignored by the target radio network node.
17. The method according to claim 9 , wherein:
the message is a HANDOVER REQUEST XnAP message, and
the first user plane indication comprises an information element indicating whether or not a protocol data unit (PDU) Session Resources To Be Setup List should be ignored by the target radio network node.
18. A source radio network node adapted to relay data packets between a first radio network node and a user equipment (UE), in a wireless communications network, wherein the source radio network node comprises:
a transceiver configured to communicate with at least a target radio network node in the wireless communication network; and
processing circuitry operably coupled to the transceiver, wherein the processing circuitry and the transceiver are configured to perform operations corresponding to the method of claim 1 .
19. The RAN mode of claim 18 , wherein the first user plane indication comprises one or more of the following, which indicates that a user plane communication should not be setup for the UE: a value not in a range of values defined by 3GPP; a protocol data unit (PDU) Session ID; an E-UTRAN Radio Access Bearer (E-RAB) ID; a data radio bearer (DRB) ID.
20. A target radio network node arranged to handle communication in a wireless communications network that comprises a source radio network node arranged to relay data packets between a first radio network node and a user equipment (UE), wherein the target radio network node comprises:
a transceiver configured to communicate with at least the source radio network node and the UE; and
processing circuitry operably coupled to the transceiver, wherein the processing circuitry and the transceiver are configured to perform operations corresponding to the method of claim 9 .
21. The RAN mode of claim 20 , wherein:
the processing circuitry and transceiver are configured to perform the setup of a connection for the UE based on the first user plane indication by refraining from setup of user plane communication for the UE when the first user plane indication indicates that user plane communication should not be setup for the UE; and
the processing circuitry and transceiver are configured to refrain from setup of user plane communication for the UE by ignoring information in the message that relates to user plane resources.