Radio communication system, radio station, radio terminal, network apparatus, bearer control method, and computer readable medium

A first radio station configured to operate a first cell, the first radio station comprising:

• a memory storing instructions;
• and
• at least one processor configured to process the instructions to:
• communicate with a radio terminal configured to aggregate the first cell with a second cell operated by a second radio station,
• send, to a core network connected with the first radio station, a request regarding a configuration of a second bearer for transferring user data between the radio terminal and the core network,
• receive, from the core network, a response to the request regarding the configuration of the second bearer,
• send, to the second radio station, a request message for configuring the second bearer, and
• receive, from the second radio station, a response message to the request message, wherein
• the second bearer is used to send the user data through the second radio station,
• the user data for the second bearer is not sent directly between the core network and the first radio station,
• the request regarding the configuration of the second bearer includes an EUTRAN Radio Access Bearer Identity (E-RAB ID) of the second bearer and a General Packet Radio Service Tunneling Protocol (GTP) Tunnel Endpoint ID (TEID) on the second radio station, and
• the request message includes the E-RAB ID and an Uplink (UL) GTP TEID for the second bearer.

A core network configured to manage a bearer configuration for a radio terminal configured to aggregate a first cell operated by a first radio station with a second cell operated by a second radio station, the core network comprising:

• a memory storing instructions;
• and
• at least one processor configured to process the instructions to:
• receive, from the first radio station, a request regarding a configuration of a second bearer for transferring user data between the radio terminal and the core network, and
• send, to the first radio station, a response to the request regarding the configuration of the second bearer, wherein
• the second bearer is used to send the user data through the second radio station,
• the user data for the second bearer is not sent directly between the core network and the first radio station, and
• the request regarding the configuration of the second bearer includes an EUTRAN Radio Access Bearer Identity (E-RAB ID) of the second bearer, which is sent from the first radio station to the second radio station, and a General Packet Radio Service Tunneling Protocol (GTP) Tunnel Endpoint ID (TEID) on the second radio station, which corresponds to an Uplink (UL) GTP TEID for the second bearer sent from the first radio station to the second radio station.

A communication control method in a communication system, comprising:

• sending, by a first radio station which is configured to operate a first cell, to a core network which is configured to communicate with the first radio station, a request regarding a configuration of a second bearer for transferring user data between a radio terminal which is configured to aggregate the first cell with a second cell operated by a second radio station, and the core network;
• sending, by the core network, to the first radio station, a response to the request regarding the configuration of the second bearer,
• sending, by the first radio station, to the second radio station, a request message for configuring the second bearer;
• and
• sending, by the second radio station, to the first radio station, a response message to the request message, wherein
• the second bearer is used to send the user data through the second radio station,
• the user data for the second bearer is not sent directly between the core network and the first radio station,
• the request regarding the configuration of the second bearer includes an EUTRAN Radio Access Bearer Identity (E-RAB ID) of the second bearer and a General Packet Radio Service Tunneling Protocol (GTP) Tunnel Endpoint ID (TED) on the second radio station, and
• the request message includes the E-RAB ID and an Uplink (UL) GTP TEID for the second bearer.

A communication control method in a first radio station that operates a first cell, the communication control method comprising:

• communicating with a radio terminal configured to aggregate the first cell with a second cell operated by a second radio station;
• sending, to a core network connected with the first radio station, a request regarding a configuration of a second bearer for transferring user data between the radio terminal and the core network;
• receiving, from the core network, a response to the request regarding the configuration of the second bearer,
• sending, to the second radio station, a request message for configuring the second bearer;
• and
• receiving, from the second radio station, a response message to the request message, wherein
• the second bearer is used to send the user data through the second radio station,
• the user data for the second bearer is not sent directly between the core network and the first radio station,
• the request regarding the configuration of the second bearer includes an EUTRAN Radio Access Bearer Identity (E-RAB ID) of the second bearer and a General Packet Radio Service Tunneling Protocol (GTP) Tunnel Endpoint ID (TEID) on the second radio station, and
• the request message includes the E-RAB ID and an Uplink (UL) GTP TEID for the second bearer.

A communication control method in a core network that manages a bearer configuration for a radio terminal configured to aggregate a first cell operated by a first radio station with a second cell operated by a second radio station, the communication control method comprising:

• receiving, from the first radio station, a request regarding a configuration of a second bearer for transferring user data between the radio terminal and the core network;
• and
• sending, to the first radio station, a response to the request regarding the configuration of the second bearer, wherein
• the second bearer is used to send the user data through the second radio station,
• the user data for the second bearer is not sent directly between the core network and the first radio station, and
• the request regarding the configuration of the second bearer includes an EUTRAN Radio Access Bearer Identity (E-RAB ID) of the second bearer, which is sent from the first radio station to the second radio station, and a Tunnel Endpoint ID (TEID) on the second radio station, which corresponds to an Uplink (UL) GTP TEID for the second bearer sent from the first radio station to the second radio station.