Method and apparatus for IP address mangement in an IAB network

1 . A wireless network node, comprising:

at least one memory; and

at least one processor coupled with the at least one memory and configured to cause the wireless network node to:

receive an internet protocol (IP) address configuration indicating an IP address of a second distributed unit (DU),

wherein the wireless network node comprises a first DU associated with a first base station and the second DU associated with a second base station, and the wireless network node migrates from the first base station to the second base station, and

wherein the IP address configuration is received from one of the first base station and the second base station or an operation administration and maintenance (OAM) according to an IP address allocation scheme; and

initiate an F1 interface setup with the second base station using the IP address of the second DU.

2 . The wireless network node of claim 1 , wherein in the case of a base station based IP address allocation scheme is applied and a mobile termination (MT) of the wireless network node has been handed over from the first base station to the second base station, the IP address configuration is received from the second base station; or

wherein in the case of a base station based IP address allocation scheme is applied and the MT of the wireless network node has not been handed over from the first base station to the second base station, the IP address configuration is received from the first base station.

3 . The wireless network node of claim 1 , wherein the at least one processor is configured to cause the wireless network node to receive an IP address of the second base station from the first base station.

4 . The wireless network node of claim 2 , wherein in the case that the IP address configuration is received from one of the first base station and the second base station, the at least one processor is configured to cause the wireless network node to transmit an IP address request for the IP address of the second DU to the one of the first base station and the second base station;

wherein at least one of the IP address request and the IP address configuration includes an indicator indicating whether the IP address request or the IP address configuration is for the first DU or the second DU.

5 . The wireless network node of claim 1 , wherein in the case that the IP address configuration is received from the OAM, the at least one processor is configured to cause the wireless network node to transmit an IP address report to report the IP address of the second DU to one of the first base station and the second base station; and

wherein the IP address report includes an indicator indicating whether the IP address report is for the first DU or the second DU.

6 . The wireless network node of claim 5 , wherein in the case that a mobile termination (MT) of the wireless network node has been handed over from the first base station to the second base station, the one of the first base station and the second base station is the second base station; or

in the case that the MT of the wireless network node has not been handed over from the first base station to the second base station, the one of the first base station and the second base station is the first base station.

7 . A wireless network node, comprising:

at least one memory; and

at least one processor coupled with the at least one memory and configured to cause the wireless network node to:

fully reuse or partially reuse internet protocol (IP) addresses of a first distributed unit (DU) as IP addresses of a second DU, wherein the wireless network node comprises the first DU associated with a first base station and the second DU associated with a second base station, and the wireless network node migrates from the first base station to the second base station, and

initiate an F1 interface setup with the second base station using at least one of the IP addresses of the second DU.

8 . The wireless network node of claim 7 , wherein in the case of fully reusing the IP addresses of the first DU, the at least one processor is configured to cause the wireless network node to transmit a full reuse indication to one of the first base station and the second base station; or

wherein in the case of partially reusing the IP addresses of the first DU, the at least one processor is configured to cause the wireless network node to transmit the IP addresses used by the second DU to one of the first base station and the second base station.

9 . The wireless network node of claim 8 , wherein in the case that a mobile termination (MT) of the wireless network node has been handed over from the first base station to the second base station, the one of the first base station and the second base station is the second base station; or

in the case that the MT of the wireless network node has not been handed over from the first base station to the second base station, the one of the first base station and the second base station is the first base station.

10 . The wireless network node of claim 8 , wherein transmitting the IP addresses used by the second DU comprises transmitting a respective IP address for each usage of the second DU.

11 . A first base station, comprising:

at least one memory; and

at least one processor coupled with the at least one memory and configured to cause the first base station to:

receive, from a second base station, an internet protocol (IP) address for an F1 interface between a wireless network node and the second base station, wherein the wireless network node migrates from the first base station to the second base station, and the wireless network node comprises a first distributed unit (DU) associated with the first base station and a second DU associated with the second base station;

transmit, to the wireless network node, an IP address configuration indicating the IP address for the F1 interface; and

perform a procedure to migrate a mobile termination (MT) of the wireless network node from the first base station to the second base station.

12 . The first base station of claim 11 , wherein in the case that an F1 interface setup between the wireless network node and the second base station precedes migration of the MT of the wireless network node, the IP address for the F1 interface includes an IP address of the second DU of the wireless network node.

13 . The first base station of claim 11 , wherein the IP address configuration comprises an indicator indicating whether the IP address for the F1 interface is for the first DU or the second DU.

14 . The first base station of claim 11 , wherein the at least one processor is configured to cause the first base station to:

receive an IP address of the second base station from the second base station; and

transmit the IP address of the second base station to the wireless network node for the F1 interface between the wireless network node and the second base station.

15 . The first base station of claim 11 , wherein the at least one processor is configured to cause the first base station to remove an F1 interface between the wireless network node and the first base station in response to a full migration of the wireless network node from the first base station to the second base station, transmit, to the second base station, an indication indicating the removal of the F1 interface between the wireless network node and the first base station for release of an IP address of the first DU of the wireless network node.

16 . A method performed by a wireless network node, the method comprising:

receiving an internet protocol (IP) address configuration indicating an IP address of a second distributed unit (DU),

wherein the wireless network node comprises a first DU associated with a first base station and the second DU associated with a second base station, and the wireless network node migrates from the first base station to the second base station, and

wherein the IP address configuration is received from one of the first base station and the second base station or an operation administration and maintenance (OAM) according to an IP address allocation scheme; and

initiating an F1 interface setup with the second base station using the IP address of the second DU.

17 . The method of claim 16 , wherein in the case of a base station-based IP address allocation scheme is applied and a mobile termination (MT) of the wireless network node has been handed over from the first base station to the second base station, the IP address configuration is received from the second base station; or

wherein in the case of a base station-based IP address allocation scheme is applied and the MT of the wireless network node has not been handed over from the first base station to the second base station, the IP address configuration is received from the first base station.

18 . The method of claim 16 , further comprising receiving an IP address of the second base station from the first base station.

19 . The method of claim 17 , further comprising, in the case that the IP address configuration is received from one of the first base station and the second base station, transmitting an IP address request for the IP address of the second DU to the one of the first base station and the second base station;

wherein at least one of the IP address request and the IP address configuration includes an indicator indicating whether the IP address request or the IP address configuration is for the first DU or the second DU.

20 . The method of claim 16 , further comprising, in the case that the IP address configuration is received from the OAM, transmitting an IP address report to report the IP address of the second DU to one of the first base station and the second base station; and

wherein the IP address report includes an indicator indicating whether the IP address report is for the first DU or the second DU.