Method and device for communication between network entities in cloud LAN environment

A distributed unit (DU) in a wireless communication system, the DU comprising;

• a transceiver configured to transmit and receive a signal;
• and
• a controller configured to:
• transmit, to a central unit (CU), a fronthaul interface setup request message including first information for setting up a fronthaul interface with the CU,
• receive, from the CU, a fronthaul interface setup response message including second information for setting up the fronthaul interface with the DU, in response to the fronthaul interface setup request message,
• set up the fronthaul interface with the CU based on the first information and the second information,
• receive, from the CU, a user equipment (UE) context modification request message to modify an established UE context,
• perform a modification of the established UE context based on the UE context modification request message,
• transmit, to the CU, a UE context modification response message in response to the UE context modification request message, and
• perform communication with the CU through a set-up fronthaul interface and communication with a UE associate with the modified UE context.

A method performed by a central unit (CU) in a wireless communication system, the method comprising:

• receiving, from a distributed unit (DU), a fronthaul interface setup request message including first information for setting up a fronthaul interface with the CU;
• transmitting, to the DU, a fronthaul interface setup response message including second information for setting up the fronthaul interface with the DU, in response to the fronthaul interface setup request message;
• setting up the fronthaul interface with the DU based on the first information and the second information;
• transmitting, to the DU, a user equipment (UE) context modification request message to modify an established UE context;
• receiving, from the DU, a UE context modification response message in response to the UE context modification request message;
• and
• performing communication with the CU through a set-up -fronthaul interface and communication with a UE associate with the modified UE context via the DU.

A central unit (CU) in a wireless communication system, the CU comprising:

• a transceiver configured to transmit and receive a signal;
• and
• a controller configured to:
• receive, from a distributed unit (DU), a fronthaul interface setup request message including first information for setting up a fronthaul interface with the CU,
• transmit, to the DU, a fronthaul interface setup response message including second information for setting up the fronthaul interface with the DU, in response to the fronthaul interface setup request message,
• set up the fronthaul interface with the DU based on the first information and the second information,
• transmit, to the DU, a user equipment (UE) context modification request message to modify an established UE context,
• receive, from the DU, a UE context modification response message in response to the UE context modification request message, and
• perform communication with the CU through a set-up fronthaul interface and communication with a UE associate with the modified UE context via the DU.