# US 2019/0174365 A1 · Communication method, apparatus, and system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0174365 A1 - Document ID: US20190174365A1 - Status: Published application - Kind: A1 - Application number: 16/271,457 - Filed: 2019-02-08 - Published: 2019-06-06 - Earliest claimed: 2016-08-12 - Assignees: Huawei Technologies Co., Ltd. - Applicants: Huawei Technologies Co., Ltd. - Inventors: Bingzhao LI; Yan WANG; Wei QUAN; Jian ZHANG; Xiaodong YANG - Web page: https://patentgrep.com/patent/US20190174365A1 ## CPC - H04W 36/0033: {with transfer of context information} - H04W 36/12: Reselecting a serving backbone network switching or routing node - H04W 76/20: Manipulation of established connections - 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 apparatus, and a system. The communication method includes: receiving, by a terminal device, a context identifier sent by a second radio access network device, and sending, to a first radio access network device, a first message that includes the context identifier; receiving, by a core network device, a second message sent by the first radio access network device, and sending, to the second radio access network device, a message that includes the context identifier; and receiving, by the core network device, context information of the terminal device that is sent by the second radio access network device, and sending the context information to the first radio access network device. Therefore, communication between the first radio access network device and the second radio access network device is ensured, and working efficiency is improved. ## Claims ### Claim 1 A radio access network device, comprising: a storage medium including executable instructions; and a processor; wherein the executable instructions, when executed by the processor, cause the apparatus to: receive, from a terminal device, a first message that comprises a context identifier; decode the first message that comprises the context identifier, wherein the context identifier comprises an identifier of a second radio access network device and an identifier of the terminal device that is allocated by the second radio access network device; send a second message to a core network device, wherein the second message comprises the context identifier; and receive context information of the terminal device from the core network device, wherein the context information of the terminal device is associated with the identifier of the terminal device. ### Claim 2 (depends on 1) The radio access network device according to claim 1, wherein the context identifier further comprises public land mobile network (PLMN) information corresponding to the second radio access network device and/or an area identifier corresponding to the second radio access network device. ### Claim 3 (depends on 1) The radio access network device according to claim 1, wherein the first message and the second message further comprise the PLMN information corresponding to the second radio access network device and/or the area identifier corresponding to the second radio access network device. ### Claim 4 (depends on 1) The radio access network device according to claim 1, wherein the first message further comprises indication information, and the indication information indicates that an area identifier corresponding to the radio access network device is different from the area identifier corresponding to the second radio access network device. ### Claim 5 (depends on 1) The radio access network device according to claim 1, wherein the executable instructions, when executed by the processor, further cause the apparatus to: determine, based on the context identifier, whether additional information needs to be obtained, wherein the additional information comprises the PLMN information corresponding to the second radio access network device and/or the area identifier corresponding to the second radio access network device; if it is determined that the additional information needs to be obtained, send an additional-information request message to the terminal device; and receive the additional information from the terminal device, wherein the second message further comprises the additional information. ### Claim 6 (depends on 1) The radio access network device according to claim 1, wherein the second message further comprises an identifier of the radio access network device. ### Claim 7 (depends on 1) The radio access network device according to claim 1, wherein the executable instructions, when executed by the processor, further cause the apparatus to: receive verification information from the terminal device; wherein the second message further comprises the verification information and information about a serving cell in which the radio access network device serves the terminal device. ### Claim 8 A radio access network device, comprising: a storage medium including executable instructions; and a processor; wherein the executable instructions, when executed by the processor, cause the apparatus to: allocate an identifier of a terminal device to the terminal device; send a context identifier to the terminal device, wherein the context identifier comprises an identifier of the radio access network device and the identifier of the terminal device; receive, from a core network device, a message that comprises the context identifier; determine context information of the terminal device based on the message that comprises the context identifier, wherein the context information of the terminal device is associated with the identifier of the terminal device; and send the context information of the terminal device to the core network device. ### Claim 9 (depends on 8) The radio access network device according to claim 8, wherein the context identifier further comprises public land mobile network (PLMN) information corresponding to the radio access network device and/or an area identifier corresponding to the radio access network device. ### Claim 10 (depends on 8) The radio access network device according to claim 8, wherein the message that is received by the receiver from the core network device and that comprises the context identifier further comprises the PLMN information corresponding to the radio access network device and/or the area identifier corresponding to the radio access network device. ### Claim 11 (depends on 8) The radio access network device according to claim 8, wherein the message that is received by the receiver from the core network device and that comprises the context identifier further comprises at least one of an identifier of a first radio access network device, PLMN information corresponding to the first radio access network device, and an area identifier corresponding to the first radio access network device, wherein the first radio access network device is a radio access network device that serves the terminal device. ### Claim 12 A core network device, comprising: a storage medium including executable instructions; and a processor; wherein the executable instructions, when executed by the processor, cause the apparatus to: receive a second message from a first radio access network device; decode the second message, wherein the second message comprises a context identifier of a terminal device, and the context identifier comprises an identifier of a second radio access network device and an identifier of the terminal device that is allocated by the second radio access network device; send a third message to a second core network device or the second radio access network device, wherein the third message comprises the context identifier; receive context information of the terminal device from the second core network device or the second radio access network device, wherein the context information is associated with the identifier of the terminal device; and send the context information to the first radio access network device. ### Claim 13 (depends on 12) The core network device according to claim 12, wherein the context identifier further comprises public land mobile network (PLMN) information corresponding to the second radio access network device and/or an area identifier corresponding to the second radio access network device. ### Claim 14 (depends on 12) The core network device according to claim 12, wherein the second message and the third message further comprise the PLMN information corresponding to the second radio access network device and/or the area identifier corresponding to the second radio access network device. ### Claim 15 (depends on 12) The core network device according to claim 12, wherein the second message and the third message further comprise verification information of the terminal device and information about a serving cell in which the first radio access network device serves the terminal device. ### Claim 16 A core network device, comprising: a storage medium including executable instructions; and a processor; wherein the executable instructions, when executed by the processor, cause the apparatus to: receive a fourth message from a first radio access network device or a first core network device; decode the fourth message, wherein the fourth message comprises a context identifier of a terminal device, and the context identifier comprises an identifier of a second radio access network device and an identifier of the terminal device that is allocated by the second radio access network device; send, to the second radio access network device, a message that comprises the context identifier; receive context information of the terminal device from the second radio access network device, wherein the context information of the terminal device is associated with the identifier of the terminal device; and send the context information to the first radio access network device or the first core network device. ### Claim 17 (depends on 16) The core network device according to claim 16, wherein the context identifier further comprises public land mobile network (PLMN) information corresponding to the second radio access network device and/or an area identifier corresponding to the second radio access network device. ### Claim 18 (depends on 16) The core network device according to claim 16, wherein the fourth message and the message that comprises the context identifier further comprise the PLMN information corresponding to the second radio access network device and/or the area identifier corresponding to the second radio access network device. ### Claim 19 (depends on 16) The core network device according to claim 16, wherein the fourth message further comprises an identifier of the first radio access network device. ### Claim 20 (depends on 16) The core network device according to claim 16, wherein the fourth message further comprises verification information and information about a serving cell in which the first radio access network device serves the terminal device.