# US 12,764,694 B2 · Techniques to facilitate network slice service continuity for mobile network environments > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,764,694 B2 - Document ID: US12764694B2 - Status: Granted - Kind: B2 - Application number: 18/490,247 - Filed: 2023-10-19 - Published: 2025-04-24 - Granted: 2026-10-13 - Earliest claimed: 2023-10-19 - Assignees: Cisco Technology, Inc. - Applicants: Cisco Technology, Inc. - Inventors: Ravi Shekhar; Dishant Mukesh Parikh; Vimal Srivastava - Web page: https://patentgrep.com/patent/US12764694B2 ## CPC - H04W 60/04: using triggered events - H04W 48/18: Selecting a network or a communication service - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract Provided herein are techniques to facilitate network slice service continuity in a mobile network environment. In one example, a method may include for a registration request involving a user equipment (UE), obtaining, by an Access and Mobility Management Function (AMF), subscription information identifying primary network slices backup network slices to which the UE is subscribed in which each of the primary network slices and the backup network slices are active network slices capable of actively handling sessions for multiple UEs. The method may further include determining whether there is registration capacity for the UE with each of the network slices with which the UE is allowed registration. Based on the determining that there is registration capacity for registration of the UE, the AMF can transmit a registration response to the UE that indicating registration with the first primary network slice and the first backup network slice is accepted. ## Claims ### Claim 1 A method comprising: receiving a registration request from a first user equipment (UE) and obtaining, by an Access and Mobility Management Function (AMF), subscription information for the first UE identifying that a slice continuity service is enabled for the UE for one or more primary network slices and one or more backup network slices to which the first UE is subscribed, wherein each primary network slice of the one or more primary network slices is associated with a corresponding backup network slice of the one or more backup network slices that provide a same network service and each of the one or more primary network slices and the one or more backup network slices are active network slices capable of actively handling sessions for a plurality of user equipment; obtaining, by the AMF from a Network Slice Selection Function (NSSF) following a query to the NSSF by the AMF, registration information for the first UE identifying, based at least in part on a location of the UE and the subscription information, a first primary network slice of the one or more primary network slices and a first backup network slice of the one or more backup network slices with which the first UE is allowed registration; determining, by the AMF based on an indication obtained from a Network Slice Admission Control Function (NSACF) following a query to the NSACF by the AME, whether there is registration capacity for registration of the first UE with the first primary network slice and the first backup network slice, wherein the query subscribes the AMF to receive notifications from the NSACF indicating if a capacity threshold is met for the first primary network slice or the first backup network slice; and based on the determining that there is registration capacity for registration of the first UE with the first primary network slice and the first backup network slice, transmitting a registration response to the first UE that indicates that registration with the first primary network slice and the first backup network slice is accepted. ### Claim 2 (depends on 1) The method of claim 1, wherein the NSACF is to provide an indication to the AMF regarding whether there is registration capacity for registration of the first UE with the first primary network slice and the first backup network slice. ### Claim 3 (depends on 2) The method of claim 2, wherein the query subscribes the AMF to receive notification from the NSACF if the capacity threshold is met for the first primary network slice or the first backup network slice after it is determined, at a time of the query, that there is registration capacity for registration of the first UE with the first primary network slice and the first backup network slice. ### Claim 4 (depends on 3) The method of claim 3, further comprising: after obtaining a first indication from the NSACF indicating that there is registration capacity for the registration of the first UE with the first primary network slice and the first backup network slice, obtaining a notification from the NSACF indicating that the capacity threshold for the first primary network slice is met. ### Claim 5 (depends on 4) The method of claim 4, further comprising: for a registration request involving a second UE, based on determining, by the AMF, that the second UE is allowed registration with the first primary network slice and the first backup network slice, determining, based on the notification obtained from the NSACF that there is not registration capacity for registration of the second UE with the first primary network slice; and performing a query towards the NSACF regarding registration of the second UE with the first backup network slice, wherein the NSACF is to provide an indication to the AMF regarding whether there is registration capacity for registration of the second UE with first backup network slice. ### Claim 6 (depends on 5) The method of claim 5, further comprising: based on the determining that there is registration capacity for registration of the second UE with the first backup network slice, transmitting a registration response message to the second UE that indicates that registration with the first backup network slice is accepted and the first primary network slice is not identified in the registration response. ### Claim 7 (depends on 1) The method of claim 1, wherein the first primary network slice and the first backup network slice are each operated by different mobile network operators. ### Claim 8 (depends on 1) The method of claim 1, wherein the subscription information is obtained from a Unified Data Management (UDM) entity via a query response message that includes an enhanced Network Slice Selection Assistance Information (NSSAI) data type that includes a BackupsingleNssais data element that identifies the one or more backup network slices to which the first UE is subscribed. ### Claim 9 (depends on 1) The method of claim 1, wherein the query to the NSSF by the AMF is a query message that includes an enhanced SliceInfoForRegistration data type that includes a BackupsubscribedNssai information element that identifies the one or more backup network slices to which the first UE is subscribed. ### Claim 10 (depends on 9) The method of claim 9, wherein the registration information is included in a query response message obtained by the AMF from the NSSF that includes an enhanced AuthorizedNetworkSliceInfo data type that includes a BackupallowedNssaiList information element that identifies the one or more backup network slices with which the first UE is allowed registration. ### Claim 11 One or more non-transitory computer readable storage media encoded with instructions that, when executed by a processor, cause the processor to perform operations, comprising: receiving a registration request from a first user equipment (UE) and obtaining, by an Access and Mobility Management Function (AMF), subscription information for the first UE identifying that a slice continuity service is enabled for the UE for one or more primary network slices and one or more backup network slices to which the first UE is subscribed, wherein each primary network slice of the one or more primary network slices is associated with a corresponding backup network slice of the one or more backup network slices that provide a same network service and each of the one or more primary network slices and the one or more backup network slices are active network slices capable of actively handling sessions for a plurality of user equipment; obtaining, by the AMF from a Network Slice Selection Function (NSSF) following a query to the NSSF by the AME, registration information for the first UE identifying, based at least in part on a location of the UE and the subscription information, a first primary network slice of the one or more primary network slices and a first backup network slice of the one or more backup network slices with which the first UE is allowed registration; determining, by the AMF based on an indication obtained from a Network Slice Admission Control Function (NSACF) following a query to the NSACF by the AMF, whether there is registration capacity for registration of the first UE with the first primary network slice and the first backup network slice, wherein the query subscribes the AMF to receive notifications from the NSACF indicating if a capacity threshold is met for the first primary network slice or the first backup network slice; and based on the determining that there is registration capacity for registration of the first UE with the first primary network slice and the first backup network slice, transmitting a registration response to the first UE that indicates that registration with the first primary network slice and the first backup network slice is accepted. ### Claim 12 (depends on 11) The media of claim 11, wherein the NSACF is to provide an indication to the AMF regarding whether there is registration capacity for registration of the first UE with the first primary network slice and the first backup network slice. ### Claim 13 (depends on 12) The media of claim 12, wherein the query subscribes the AMF to receive the notification from the NSACF if the capacity threshold is met for the first primary network slice or the first backup network slice after it is determined, at a time of the query, that there is registration capacity for registration of the first UE with the first primary network slice and the first backup network slice. ### Claim 14 (depends on 13) The media of claim 13, further comprising instructions that, when executed by a processor, cause the processor to perform further operations, comprising: after obtaining a first indication from the NSACF indicating that there is registration capacity for the registration of the first UE with the first primary network slice and the first backup network slice, obtaining a notification from the NSACF indicating that the capacity threshold for the first primary network slice is met. ### Claim 15 (depends on 14) The media of claim 14, further comprising instructions that, when executed by a processor, cause the processor to perform further operations, comprising: for a registration request involving a second UE, based on determining, by the AMF, that the second UE is allowed registration with the first primary network slice and the first backup network slice, determining, based on the notification obtained from the NSACF that there is not registration capacity for registration of the second UE with the first primary network slice; and performing a query towards the NSACF regarding registration of the second UE with the first backup network slice, wherein the NSACF is to provide an indication to the AMF regarding whether there is registration capacity for registration of the second UE with first backup network slice. ### Claim 16 A system comprising: at least one memory element for storing data; and at least one processor for executing instructions associated with the data, wherein executing the instructions causes the system to perform operations, comprising: receiving a registration request from a first user equipment (UE) and obtaining, by an Access and Mobility Management Function (AMF), subscription information for the first UE identifying that a slice continuity service is enabled for the UE for one or more primary network slices and one or more backup network slices to which the first UE is subscribed, wherein each primary network slice of the one or more primary network slices is associated with a corresponding backup network slice of the one or more backup network slices that provide a same network service and each of the one or more primary network slices and the one or more backup network slices are active network slices capable of actively handling sessions for a plurality of user equipment; obtaining, by the AMF from a Network Slice Selection Function (NSSF) following a query to the NSSF by the AME, registration information for the first UE identifying, based at least in part on a location of the UE and the subscription information, a first primary network slice of the one or more primary network slices and a first backup network slice of the one or more backup network slices with which the first UE is allowed registration; determining, by the AMF based on an indication obtained from a Network Slice Admission Control Function (NSACF) following a query to the NSACF by the AMF, whether there is registration capacity for registration of the first UE with the first primary network slice and the first backup network slice, wherein the query subscribes the AMF to receive notifications from the NSACF indicating if a capacity threshold is met for the first primary network slice or the first backup network slice; and based on the determining that there is registration capacity for registration of the first UE with the first primary network slice and the first backup network slice, transmitting a registration response to the first UE that indicates that registration with the first primary network slice and the first backup network slice is accepted. ### Claim 17 (depends on 16) The system of claim 16, wherein the NSACF is to provide an indication to the AMF regarding whether there is registration capacity for registration of the first UE with the first primary network slice and the first backup network slice. ### Claim 18 (depends on 17) The system of claim 17, wherein the query subscribes the AMF to receive the notification from the NSACF if the capacity threshold is met for the first primary network slice or the first backup network slice after it is determined, at a time of the query, that there is registration capacity for registration of the first UE with the first primary network slice and the first backup network slice. ### Claim 19 (depends on 18) The system of claim 18, wherein executing the instructions causes the system to perform further operations, comprising: after obtaining a first indication from the NSACF indicating that there is registration capacity for the registration of the first UE with the first primary network slice and the first backup network slice, obtaining a notification from the NSACF indicating that the capacity threshold for the first primary network slice is met. ### Claim 20 (depends on 19) The system of claim 19, wherein executing the instructions causes the system to perform further operations, comprising: for a registration request involving a second UE, based on determining, by the AMF, that the second UE is allowed registration with the first primary network slice and the first backup network slice, determining, based on the notification obtained from the NSACF that there is not registration capacity for registration of the second UE with the first primary network slice; and performing a query towards the NSACF regarding registration of the second UE with the first backup network slice, wherein the NSACF is to provide an indication to the AMF regarding whether there is registration capacity for registration of the second UE with first backup network slice.