# US 2019/0357103 A1 · Communication Method, Access Network Device, And Core Network Device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0357103 A1 - Document ID: US20190357103A1 - Status: Published application - Kind: A1 - Application number: 16/503,354 - Filed: 2019-07-03 - Published: 2019-11-21 - Earliest claimed: 2017-06-16 - Assignees: Huawei Technologies Co., Ltd. - Applicants: Huawei Technologies Co., Ltd. - Inventors: Yinghao JIN; Feng HAN; Hong LI - Web page: https://patentgrep.com/patent/US20190357103A1 ## CPC - H04W 76/11: Allocation or use of connection identifiers - H04W 24/10: Scheduling measurement reports {; Arrangements for measurement reports} - H04W 36/00: Hand-off or reselection arrangements - H04W 36/0079: {in case of hand-off failure or rejection} - H04W 36/13: {Cell handover without a predetermined boundary, e.g. virtual cells} - H04W 36/008357: {Determination of target cell based on access point [AP] properties, e.g. AP service capabilities} - H04W 48/18: Selecting a network or a communication service - H04W 88/00: Devices specially adapted for wireless communication networks, e.g. terminals, base stations or access point devices - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract Embodiments of the present invention disclose a communication method, an access network device, and a core network device. The method includes: sending, by a source access network device, to a core network device a handover message for a handover of one or more sessions of a terminal device from the source access network device to a target access network device, wherein the handover message comprises information about the target access network device and identifier information of the one or more sessions; and sending, by the core network device, a response message of the handover message to the source access network device, wherein the response message of the handover message comprises indication information indicating a reason that a session of the one or more sessions is not accepted, wherein the reason is associated with a slice corresponding to the session. ## Claims ### Claim 1 A method for handover in a wireless communication system, comprising: sending, by a source access network device, to a core network device a handover message for a handover of one or more sessions of a terminal device from the source access network device to a target access network device, wherein the handover message comprises information about the target access network device and identifier information of the one or more sessions; and sending, by the core network device, a response message of the handover message to the source access network device, wherein the response message of the handover message comprises indication information indicating a reason that a session of the one or more sessions is not accepted, wherein the reason is associated with a slice corresponding to the session. ### Claim 2 (depends on 1) The method according to claim 1, wherein the reason indicated by the indication information is one of: the slice corresponding to the session of the one or more sessions is not supported; or a radio resource is unavailable for a slice corresponding to the session. ### Claim 3 (depends on 2) The method according to claim 2, wherein the indication information is a cause value. ### Claim 4 (depends on 2) The method according to claim 2, wherein the handover message is a first handover message, and before sending the response message of the first handover message to the source access network device, the method further comprises: sending, by the core network device, a second handover message to the target access network device; and sending, by the target access network device, a response message of the second handover message to the core network device. ### Claim 5 (depends on 4) The method according to claim 4, wherein the response message of the second handover message is a handover failure message, and the response message of the first handover message is a handover preparation failure message. ### Claim 6 (depends on 5) The method according to claim 5, wherein the handover failure message comprises a cause that the target base station is failed to accept a session identified by a session identifier included in second handover message, and wherein the cause is a radio resource is unavailable for a network slice corresponding to the session. ### Claim 7 (depends on 4) The method according to claim 4, wherein the response message of the second handover message is a handover request acknowledgement message, and the response message of the first handover message is a handover command message. ### Claim 8 (depends on 7) The method according to claim 7, wherein the handover request acknowledgement message comprises a session identifier of a session failed to be setup by the target access network device and a cause corresponding to the session failed to be setup by the target access network device, and wherein the cause is a radio resource is unavailable for a slice corresponding to the session. ### Claim 9 (depends on 1) The method according to claim 1, wherein before sending the first handover message, the method further comprises: receiving, by the source access network device, a measurement report from the terminal device; and determining, by the source access network device, the target access network device according to the measurement report. ### Claim 10 (depends on 1) The method according to claim 1, wherein the one or more sessions of the terminal device comprises a first part and a second part, the first part of the one or more sessions is accepted by the target base station and the second part of the one or more sessions is not accepted by the target base station; wherein the response message of the handover message comprises identifier information associated with the first part, and the indication information indicates that a slice corresponding to the second part is not supported or a resource is unavailable for a slice corresponding to the second part. ### Claim 11 (depends on 10) The method according to claim 10, wherein the response message of the handover message is a handover command; and the method further comprises: sending, by the source access network device, the handover command to the terminal device. ### Claim 12 A wireless communication system for handover, comprising: a source access network device and a core network device; the source access network device is configured to a core network device a handover message for a handover of one or more sessions of a terminal device from the source access network device to a target access network device, wherein the handover message comprises information about the target access network device and identifier information of the one or more sessions; and the core network device is configured to send a response message of the handover message to the source access network device, wherein the response message of the handover message comprises indication information indicating a reason that a session of the one or more sessions is not accepted, wherein the reason is associated with a slice corresponding to the session. ### Claim 13 (depends on 12) The system according to claim 12, wherein the reason indicated by the indication information is one of: the slice corresponding to the session of the one or more sessions is not supported; or a radio resource is unavailable for a slice corresponding to the session. ### Claim 14 (depends on 12) The system according to claim 12, wherein the indication information is a cause value. ### Claim 15 (depends on 12) The system according to claim 12, wherein the handover message is a first handover message, and the system further comprises a target access network device; the core network device is further configured to send a second handover message to the target access network device; and the target access network device is configured to send a response message of the second handover message to the core network device. ### Claim 16 (depends on 15) The system according to claim 15, wherein the response message of the second handover message is a handover failure message, and the response message of the first handover message is a handover preparation failure message. ### Claim 17 (depends on 17) The system according to claim 17, wherein the handover failure message comprises a cause that the target base station is failed to accept a session identified by a session identifier included in second handover message, and wherein the cause is a radio resource is unavailable for a network slice corresponding to the session. ### Claim 18 (depends on 15) The system according to claim 15, wherein the response message of the second handover message is a handover request acknowledgement message, and the response message of the first handover message is a handover command message. ### Claim 19 (depends on 18) The system according to claim 18, wherein the handover request acknowledgement message comprises a session identifier of a session failed to be setup by the target access network device and a cause corresponding to the session failed to be setup by the target access network device, and wherein the cause is a radio resource is unavailable for a slice corresponding to the session. ### Claim 20 (depends on 12) The system according to claim 12, wherein the source access network device is further configured to receive a measurement report from the terminal device; and determine the target access network device according to the measurement report. ### Claim 21 (depends on 12) The system according to claim 12, wherein the one or more sessions of the terminal device comprises a first part and a second part, the first part of the one or more sessions is accepted by the target base station and the second part of the one or more sessions is not accepted by the target base station; wherein the response message of the handover message comprises identifier information associated with the first part, and the indication information indicates that a slice corresponding to the second part is not supported or a resource is unavailable for a slice corresponding to the second part. ### Claim 22 (depends on 21) The system according to claim 21, wherein the response message of the handover message is a handover command; and the source access network device is further configured to send the handover command to the terminal device.