Radio bearer reconfiguration

1 . An apparatus configured as a central unit, comprising at least one processor, and at least one memory including computer program code, wherein the at least one memory and the computer program code are configured, with the at least one processor, to cause the apparatus to:

receive, from a distributed unit, an indication for assisting in determining a reconfiguration having an effect on at least one radio bearer for providing a multicast communication service or a broadcast communication service to at least one terminal device, the at least one radio bearer comprising at least a point-to-point leg for providing said service,

wherein the indication comprises a request to reconfigure the at least one radio bearer from a split common radio bearer to a single radio bearer and the reconfiguration comprises a release of a point-to-multipoint leg from the at least one radio bearer, or

wherein the indication comprises a request to reconfigure the at least one radio bearer from a single radio bearer to a split common radio bearer and the reconfiguration comprises an addition of a point-to-multipoint leg to the at least one radio bearer; and

transmit, to the at least one terminal device, a message indicative of the reconfiguration.

2 . The apparatus according to claim 1 , wherein the at least one radio bearer comprises the split common radio bearer comprising the point-to-multipoint leg, wherein the reconfiguration comprises a release of the split common radio bearer;

wherein the reconfiguration further comprises setting up at least one dedicated radio bearer comprising a point-to-point leg for providing said service to the at least one terminal device such that one or more dedicated radio bearers are configured per terminal device.

3 . The apparatus according to claim 1 , wherein the at least one radio bearer comprises a plurality of dedicated radio bearers configured such that one or more dedicated radio bearers are configured per terminal device, wherein the reconfiguration comprises a release of the plurality of dedicated radio bearers;

wherein the reconfiguration further comprises setting up a split common radio bearer comprising a point-to-point leg and a point-to-multipoint leg for providing said service to the at least one terminal device.

4 . The apparatus according to claim 1 , wherein the reconfiguration is transmitted to a plurality of terminal devices by using a group radio resource control reconfiguration message, or by using a plurality of individual radio resource control reconfiguration messages.

5 . The apparatus according to claim 1 , wherein a part of the reconfiguration is associated with the distributed unit;

wherein said part of the reconfiguration is received within or together with the indication received from the distributed unit.

6 . The apparatus according to claim 1 , wherein the apparatus is further caused to:

transmit, to the distributed unit, a request for enabling or disabling the distributed unit to transmit the indication to the apparatus.

7 . The apparatus according to claim 1 , wherein the indication received from the distributed unit comprises at least a request for triggering the reconfiguration.

8 . The apparatus according to claim 1 , wherein the indication received from the distributed unit comprises at least layer 1 measurement information associated with a plurality of terminal devices comprising the at least one terminal device.

9 . An apparatus configured as a distributed unit, comprising at least one processor, and at least one memory including computer program code, wherein the at least one memory and the computer program code are configured, with the at least one processor, to cause the apparatus to:

determine that at least one condition regarding providing a multicast communication service or a broadcast communication service to at least one terminal device is fulfilled;

based on the determining, transmit, to a central unit, an indication for assisting the central unit in determining a reconfiguration having an effect on at least one radio bearer, the at least one radio bearer comprising at least a point-to-point leg for providing said service,

wherein the indication comprises a request to reconfigure the at least one radio bearer from a split common radio bearer to a single radio bearer or a request to reconfigure the at least one radio bearer from a single radio bearer to a split common radio bearer; and

transmit, to the at least one terminal device, a set of data associated with the multicast communication service or the broadcast communication service by utilizing the at least one radio bearer.

10 . The apparatus according to claim 9 , wherein the at least one condition indicates whether or not the at least one terminal device is evaluated to benefit from a point-to-multipoint leg.

11 . The apparatus according to claim 9 , wherein the at least one condition is determined to be fulfilled based at least partly by comparing a number of terminal devices with a pre-defined threshold value, wherein the number of terminal devices are evaluated to benefit from a point-to-multipoint leg;

wherein the number of terminal devices benefitting from the point-to-multipoint leg is determined based at least partly on layer 1 measurement information from a plurality of terminal devices comprising at least the number of terminal devices.

12 . The apparatus according to claim 9 , wherein the at least one radio bearer comprises the split common radio bearer comprising the point-to-multipoint leg, wherein the reconfiguration comprises a release of the split common radio bearer;

wherein the reconfiguration further comprises setting up at least one dedicated radio bearer comprising a point-to-point leg for providing said service to the at least one terminal device such that one or more dedicated radio bearers are configured per terminal device.

13 . The apparatus according to claim 9 , wherein the at least one radio bearer comprises a plurality of dedicated radio bearers configured such that one or more dedicated radio bearers are configured per terminal device, wherein the reconfiguration comprises a release of the plurality of dedicated radio bearers;

wherein the reconfiguration further comprises setting up a split common radio bearer comprising a point-to-point leg and a point-to-multipoint leg for providing said service to the at least one terminal device.

14 . The apparatus according to claim 9 , wherein the apparatus is further caused to:

receive, from the central unit, a message comprising a reconfiguration message indicative of the reconfiguration;

transmit, to the at least one terminal device, the reconfiguration message indicative of the reconfiguration.

15 . A method for a central unit, the method comprising:

receiving, from a distributed unit, an indication for assisting in determining a reconfiguration having an effect on at least one radio bearer for providing a multicast communication service or a broadcast communication service to at least one terminal device, the at least one radio bearer comprising at least a point-to-point leg for providing said service,

wherein the indication comprises a request to reconfigure the at least one radio bearer from a split common radio bearer to a single radio bearer and the reconfiguration comprises a release of a point-to-multipoint leg from the at least one radio bearer, or wherein the indication comprises a request to reconfigure the at least one radio bearer from a single radio bearer to a split common radio bearer and the reconfiguration comprises an addition of a point-to-multipoint leg to the at least one radio bearer; and

transmitting, to the at least one terminal device, a message indicative of the reconfiguration.

16 . A method for a distributed unit, the method comprising:

determining that at least one condition regarding providing a multicast communication service or a broadcast communication service to at least one terminal device is fulfilled;

based on the determining, transmitting, to a central unit, an indication for assisting the central unit in determining a reconfiguration having an effect on at least one radio bearer, the at least one radio bearer comprising at least a point-to-point leg for providing said service, wherein the indication comprises a request to reconfigure the at least one radio bearer from a split common radio bearer to a single radio bearer or a request to reconfigure the at least one radio bearer from a single radio bearer to a split common radio bearer; and

transmitting, to the at least one terminal device, a set of data associated with the multicast communication service or the broadcast communication service by utilizing the at least one radio bearer.