Radio access network node, radio terminal, and method therefor
A secondary node ( 2 ) transmits to a radio terminal ( 3 ), via a master node ( 1 ), a first RRC message indicating an execution condition of a conditional primary cell change of a primary cell of a secondary cell group from a first cell to a second cell. In addition, the secondary node ( 2 ) receives, via the master node ( 1 ), a second RRC message that is transmitted from the radio terminal ( 3 ) in response to a satisfaction of the execution condition. This contributes to, for example, allowing the secondary node to be aware of a satisfaction of an execution condition of a conditional PSCell change where RRC signaling between the secondary node and the radio terminal is performed via the master node.
1. A radio terminal comprising:
at least one memory; and
at least one processor coupled to the at least one memory and configured to:
perform dual connectivity of a master cell group associated with a master node (MN) and a secondary cell group associated with a secondary node (SN);
receive a third Radio Resource Control (RRC) message of an MN Radio Access Technology (RAT) from the master node, the third RRC message containing a first RRC message of an SN RAT from the SN, the first RRC message containing an execution condition of a conditional secondary cell group primary cell (PSCell) change from a first cell to a second cell; and
transmit a fourth RRC message of the MN RAT containing a second RRC message of the SN RAT to the master node, after the execution condition is satisfied.
2. The radio terminal according to claim 1 , wherein the MN RAT and the SN RAT are different RATs.
3. The radio terminal according to claim 1 , wherein the MN RAT and the SN RAT are the same RAT.
4. The radio terminal according to claim 2 , wherein each of the MN RAT and the SN RAT is either NR or LTE.
5. A master node (MN) of dual connectivity for a radio terminal, the master node comprising:
at least one memory; and
at least one processor coupled to the at least one memory and configured to:
receive from a secondary node (SN) of the dual connectivity a first Radio Resource Control (RRC) message of an SN RAT containing an execution condition of a conditional secondary cell group primary cell (PSCell) change from a first cell to a second cell;
transmit to the radio terminal a third RRC message of an MN RAT containing the first RRC message;
receive from the radio terminal a fourth RRC message of the MN RAT containing a second RRC message of the SN RAT, after the execution condition is satisfied; and
send the second RRC message to the SN.
6. The MN according to claim 5 , wherein the MN RAT and the SN RAT are different RATs.
7. The MN according to claim 5 , wherein the MN RAT and the SN RAT are the same RAT.
8. The radio terminal according to claim 6 , wherein each of the MN RAT and the SN RAT is either NR or LTE.
9. A method performed by a radio terminal, the method comprising:
performing dual connectivity of a master cell group associated with a master node (MN) and a secondary cell group associated with a secondary node (SN);
receiving a third Radio Resource Control (RRC) message of an MN Radio Access Technology (RAT) from the master node, the third RRC message containing a first RRC message of an SN RAT from the SN, the first RRC message containing an execution condition of a conditional secondary cell group primary cell (PSCell) change from a first cell to a second cell; and
transmitting a fourth RRC message of the MN RAT containing a second RRC message of the SN RAT to the master node, after the execution condition is satisfied.
10. The method according to claim 9 , wherein the MN RAT and the SN RAT are different RATs.
11. The method according to claim 9 , wherein the MN RAT and the SN RAT are the same RAT.
12. The method according to claim 10 , wherein each of the MN RAT and the SN RAT is either NR or LTE.
13. A method performed by a master node (MN) of dual connectivity for a radio terminal, the master node comprising:
receiving from a secondary node (SN) of the dual connectivity a first Radio Resource Control (RRC) message of an SN RAT containing an execution condition of a conditional secondary cell group primary cell (PSCell) change from a first cell to a second cell;
transmitting to the radio terminal a third RRC message of an MN RAT containing the first RRC message;
receiving from the radio terminal a fourth RRC message of the MN RAT containing a second RRC message of the SN RAT, after the execution condition is satisfied; and
sending the second RRC message to the SN.
14. The method according to claim 13 , wherein the MN RAT and the SN RAT are different RATs.
15. The method according to claim 13 , wherein the MN RAT and the SN RAT are the same RAT.
16. The method according to claim 14 , wherein each of the MN RAT and the SN RAT is either NR or LTE.