# US 11,122,414 B2 · Method and apparatus for session management function selection > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,122,414 B2 - Document ID: US11122414B2 - Status: Granted - Kind: B2 - Application number: 16/776,421 - Filed: 2020-01-29 - Published: 2020-05-28 - Granted: 2021-09-14 - Earliest claimed: 2017-03-31 - Assignees: Zte Corporation - Applicants: Zte Corporation - Inventors: Jinguo Zhu - Web page: https://patentgrep.com/patent/US11122414B2 ## CPC - H04W 8/06: Registration at serving network Location Register, VLR or user mobility server - H04W 8/18: Processing of user or subscriber data, e.g. subscribed services, user preferences or user profiles; Transfer of user or subscriber data - H04W 8/10: between location register and external networks - H04W 48/18: Selecting a network or a communication service - H04W 60/00: Affiliation to network, e.g. registration; Terminating affiliation with the network, e.g. de-registration - H04W 60/002: {Registration for requesting network slices} - H04L 12/00: Data switching networks (interconnection of, or transfer of information or other signals between, memories, input/output devices or central processing units G06F13/00) - H04W 36/12: Reselecting a serving backbone network switching or routing node - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract A method and apparatus for selecting session management functions are disclosed. In one embodiment, a method includes: receiving a registration request from a user equipment (UE) device; sending access location information and allowed slice information associated with the UE device to a logical network database; receiving accepted slice information and associated slice information of a home network from the logical network database; and sending a registration accepted message to the UE device, wherein the registration accepted message comprises the accepted slice information. ## Claims ### Claim 1 A method performed by an Access and Mobility Management Function (AMF) of a serving network, comprising: receiving a requested Network Slice Selection Assistance Information (NSSAI) from a wireless communication device visiting the serving network; sending a network slice instance (NSI) selection request message to a first database that maintains function information pertaining to at least one NSI, wherein the NSI-selection request message comprises the requested NSSAI, and an indication that a requested data session is home routed through a home network of the wireless communication device; receiving a NSI-selection response message from the first database, wherein the NSI selection response message comprises, in response to the indication, an address of a network function repository function (NFRF) in the home network; selecting a first session management function associated with a NSI of the serving network; and selecting a second session management function associated with a NSI of the home network. ### Claim 2 (depends on 1) The method of claim 1 further comprising: sending a first session management function selection request message to a second database; receiving a first session management function selection response message, wherein the first session management function is selected based on the first session management function selection response message; enabling a second session management function selection request message to be sent to a third database; and receiving a second session management function selection response message, wherein the second session management function is selected based on the second session management function selection response message. ### Claim 3 (depends on 1) The method of claim 1, wherein the NSI selection response message comprises slice information of the home network. ### Claim 4 An apparatus of a serving network, comprising: at least one processor and a memory coupled to the at least one processor, the at least one processor configured to: receive a requested NSSAI from a wireless communication device visiting the serving network; send a network slice instance (NSI) selection request message to a first database that maintains function information pertaining to at least one NSI, wherein the NSI selection request message comprises the requested NSSAI and an indication that a requested data session is home routed through a home network of the wireless communication device; receive a NSI selection response message from the first database, wherein the NSI selection response message comprises, in response to the indication, an address of a network function repository function (NFRF) in the home network; select a first session management function associated with a NSI of the serving network; and select a second session management function associated with a NSI of the home network. ### Claim 5 (depends on 4) The apparatus of claim 4, wherein the at least one processor is further configured to: send a first session management function selection request message to a seeond database; receive a first session management function selection response message, wherein the first session management function is selected based on the first session management function selection response message; enable a second session management function selection request message to be sent to a third database; and receive a second session management function selection response message, wherein the second session management function is selected based on the second session management function selection response message. ### Claim 6 (depends on 4) The apparatus of claim 4, wherein the NSI selection response message comprises slice information of the home network. ### Claim 7 A non-transitory computer-readable medium having computer-executable instructions stored thereon, the computer-executable instructions, when executed by a processor of a serving network, causing the processor to perform: receiving a requested Network Slice Selection Assistance Information (NSSAI) from a wireless communication device visiting the serving network; sending a network slice instance (NSI) selection request message to a first database that maintains function information pertaining to at least one NSI, wherein the NSI selection request message comprises the requested NSSAI, and an indication that a requested data session is home routed through a home network of the wireless communication device; receiving a NSI selection response message from the first database, wherein the NSI selection response message comprises, in response to the indication, an address of a network function repository function (NFRF) in the home network; selecting a first session management function associated with a NSI of the serving network; and selecting a second session management function associated with a NSI of the home network. ### Claim 8 (depends on 7) The non-transitory computer-readable medium of claim 7, wherein the computer-executable instructions, when executed by a processor, further causing the processor to perform: sending a first session management function selection request message to a second database; receiving a first session management function selection response message, wherein the first session management function is selected based on the first session management function selection response message; enabling a second session management function selection request message to be sent to a third database; and receiving a second session management function selection response message, wherein the second session management function is selected based on the second session management function selection response message. ### Claim 9 (depends on 7) The non-transitory computer-readable medium of claim 7, wherein the NSI selection response message comprises slice information of tag home network.