# US 11,115,876 B2 · Service continuity implementation method, device, and service continuity implementation system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,115,876 B2 - Document ID: US11115876B2 - Status: Granted - Kind: B2 - Application number: 16/716,049 - Filed: 2019-12-16 - Published: 2020-04-16 - Granted: 2021-09-07 - Earliest claimed: 2017-06-23 - Assignees: Huawei Technologies Co., Ltd. - Applicants: Huawei Technologies Co., Ltd. - Inventors: Dekui Sun; Han Zhou - Web page: https://patentgrep.com/patent/US11115876B2 ## CPC - H04W 36/0016: {Hand-off preparation specially adapted for end-to-end data sessions} - H04W 36/00695: {using split of the control plane or user plane} - H04W 36/12: Reselecting a serving backbone network switching or routing node - H04W 36/185: {using make before break} - H04W 72/12: Wireless traffic scheduling - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract A service continuity implementation method, a device, and a service continuity implementation system, to ensure service continuity in a handover process, where the method includes: selecting, by a session management function entity, a target user plane function entity to serve a terminal; sending, by the session management function entity, a first message to a control device; receiving, by the session management function entity, indication information of a first application server (AS) from the control device; and sending, by the session management function entity, a first routing rule to the target user plane function entity based on the indication information of the first AS, where the first routing rule specifies that data whose destination address is an address of the first AS is to be sent to the first AS. ## Claims ### Claim 1 A service continuity implementation method, comprising: selecting, by a session management function entity, a target user plane function entity to serve a terminal; sending, by the session management function entity, first path information to the target user plane function entity; sending, by the session management function entity, second path information to a source user plane function entity, wherein the first path information and the second path information are for establishing a forwarding path between the target user plane function entity and the source user plane function entity; sending, by the session management function entity, a first message to a control device; receiving, by the session management function entity, indication information of a first application server (AS) from the control device; and sending, by the session management function entity, a first routing rule to the target user plane function entity based on the indication information of the first AS, wherein the first routing rule specifies that data whose destination address is an address of the first AS is to be sent to the first AS. ### Claim 2 (depends on 1) The service continuity implementation method according to claim 1, after selecting the target user plane function entity to serve the terminal, and before sending the first routing rule to the target user plane function entity, the service continuity implementation method further comprises sending, by the session management function entity, a second routing rule to the target user plane function entity, wherein the second routing rule specifies that data whose destination address is an address of a second AS is to be sent to a source user plane function entity, wherein the second AS is an AS currently serving the terminal, and wherein the source user plane function entity is a user plane function entity communicatively connected to the second AS. ### Claim 3 (depends on 2) The service continuity implementation method according to claim 2, after sending the first routing rule to the target user plane function entity, the service continuity implementation method further comprises sending, by the session management function entity, a second message to the target user plane function entity, wherein the second message requests deletion of the second routing rule. ### Claim 4 (depends on 1) The service continuity implementation method according to claim 1, further comprising: receiving, by the control device, the first message from the session management function entity; and sending, by the control device, the indication information of the first AS to the session management function entity. ### Claim 5 (depends on 1) The service continuity implementation method according to claim 1, further comprising: receiving, by the control device, a seventh message from the session management function entity, wherein the seventh message instructs switching the terminal from a second AS to the first AS, and wherein the second AS is an AS currently serving the terminal; and switching, by the control device, the terminal from the second AS to the first AS based on the seventh message. ### Claim 6 (depends on 1) The service continuity implementation method according to claim 1, wherein the first message comprises of location information of the target user plane function entity, and wherein of the location information of the target user plane function entity is for determining that an AS serving the terminal is the first AS. ### Claim 7 (depends on 1) The service continuity implementation method according to claim 1, wherein the indication information of the first AS comprises location information of the first AS. ### Claim 8 A session management function entity, comprising: at least one processor; and a memory storing computer-executable instructions that, when executed by the at least one processor, instruct the at least one processor to: select a target user plane function entity to serve a terminal; send first path information to the target user plane function entity; send second path information to a source user plane function entity, wherein the first path information and the second path information are for establishing a forwarding path between the target user plane function entity and the source user plane function entity; send a first message to a control device; receive indication information of a first application server (AS) from the control device; and send a first routing rule to the target user plane function entity based on the indication information of the first AS, wherein the first routing rule specifies that data whose destination address is an address of the first AS is to be sent to the first AS. ### Claim 9 (depends on 8) The session management function entity according to claim 8, wherein the computer-executable instructions, when executed, further instruct the at least one processor to send a second routing rule to the target user plane function entity after the at least one processor selects the target user plane function entity to serve the terminal and before the first routing rule is sent to the target user plane function entity, wherein the second routing rule specifies that data whose destination address is an address of a second AS is to be sent to a source user plane function entity, wherein the second AS is an AS currently serving the terminal, and wherein the source user plane function entity is a user plane function entity communicatively connected to the second AS. ### Claim 10 (depends on 9) The session management function entity according to claim 9, wherein the computer-executable instructions, when executed, further instruct the at least one processor to send a second message to the target user plane function entity after sending the first routing rule to the target user plane function entity, wherein the second message requests to delete the second routing rule. ### Claim 11 (depends on 8) The session management function entity according to claim 8, wherein the computer-executable instructions, when executed, further instruct the at least one processor to send a seventh message to the control device after sending the first routing rule to the target user plane function entity, wherein the seventh message requests switching the terminal from a second AS to the first AS, and wherein the second AS is an AS currently serving the terminal. ### Claim 12 (depends on 11) The session management function entity according to claim 11, wherein the computer-executable instructions, when executed, further instruct the at least one processor to receive an eighth message from the control device after sending the seventh message to the control device, wherein the eighth message indicates that the terminal has been switched from the second AS to the first AS. ### Claim 13 A service continuity implementation system, comprising: a session management function entity configured to: select a target user plane function entity to serve a terminal; send first path information to the target user plane function entity; send second path information to a source user plane function entity, wherein the first path information and the second path information are used to establish a forwarding path between the target user plane function entity and the source user plane function entity; and send a first message to a controller; and the controller, wherein the controller configured to send indication information of a first application server (AS), wherein the session management function entity is further configured to: receive the indication information of the first AS; and send a first routing rule to the target user plane function entity based on the indication information of the first AS, wherein the first routing rule specifies that data whose destination address is an address of the first AS is to be sent to the first AS. ### Claim 14 (depends on 13) The service continuity implementation system according to claim 13, wherein the session management function entity is further configured to send a second routing rule to the target user plane function entity, wherein the second routing rule specifies that data whose destination address is an address of a second AS is to be sent to a source user plane function entity, wherein the second AS is an AS currently serving the terminal, and wherein the source user plane function entity is a user plane function entity communicatively connected to the second AS. ### Claim 15 (depends on 14) The service continuity implementation system according to claim 14, wherein the session management function entity is further configured to send a second message to the target user plane function entity, wherein the second message requests to delete the second routing rule. ### Claim 16 (depends on 13) The service continuity implementation system according to claim 13, wherein the session management function entity is further configured to send a seventh message to the controller, wherein the seventh message requests the controller to switch the terminal from a second AS to the first AS, wherein the second AS is an AS currently serving the terminal, and wherein the controller is further configured to: receive the seventh message from the session management function entity; and switch the terminal from the second AS to the first AS. ### Claim 17 (depends on 16) The service continuity implementation system according to claim 16, wherein the controller is further configured to send an eighth message to the session management function entity, wherein the eighth message indicates to the session management function entity that the terminal has been switched from the second AS to the first AS, and wherein the session management function entity is further configured to receive the eighth message from the controller. ### Claim 18 (depends on 8) The session management function entity according to claim 8, wherein the first message comprises location information of the target user plane function entity, and wherein the location information of the target user plane function entity is for determining that an AS serving the terminal is the first AS. ### Claim 19 (depends on 13) The service continuity implementation system according to claim 13, wherein the first message comprises location information of the target user plane function entity, and wherein the location information of the target user plane function entity is for determining that an AS serving the terminal is the first AS.