# US 12,764,026 B2 · Systems and methods for network function discovery in a segmented network > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,764,026 B2 - Document ID: US12764026B2 - Status: Granted - Kind: B2 - Application number: 19/019,637 - Filed: 2025-01-14 - Published: 2025-05-15 - Granted: 2026-10-13 - Earliest claimed: 2023-03-20 - Assignees: Verizon Patent and Licensing Inc. - Applicants: Verizon Patent and Licensing Inc. - Inventors: Shanthala Kuravangi-Thammaiah; Emerando M. Delos Reyes; Sudhakar Reddy Patil - Web page: https://patentgrep.com/patent/US12764026B2 ## CPC - H04L 41/122: of virtualised topologies, e.g. software-defined networks [SDN] or network function virtualisation [NFV] - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract A method may include subscribing, by a first network repository function (NRF) located in a first segment of a network, to event information associated with a unified data management (UDM) function or a unified data repository (UDR) located in a second segment of the network. The method may also include receiving, by the first NRF and from a second NRF included in the second segment UDM or UDR information associated with the UDM or UDR located in the second segment of the network. The method may further include receiving, at the first NRF, a UDM or UDR discovery request from a network function (NF), wherein the UDM or UDR discovery request is associated with subscriber information stored in a UDM or UDR located in the second segment of the network, and responding, by the first NRF, to the discovery request. ## Claims ### Claim 1 A method, comprising: subscribing, by a first network repository function (NRF) located in a first segment of a first core network, to event information associated with at least one of a unified data management (UDM) function or a unified data repository (UDR) located in a second segment of the first core network, wherein the first core network is managed by a single telecommunications service provider and the first and second segments of the first core network are managed by the single telecommunications service provider; receiving, by the first NRF located in the first segment of the first core network and from a second NRF located in the second segment of the first core network, at least one of UDM or UDR information associated with the at least one of the UDM function or UDR located in the second segment of the first core network; receiving, by the second NRF, a status change indication associated with at least one of the UDM function or UDR located in the second segment of the first core network; and forwarding, by the second NRF and to the first NRF, a notification message identifying the status change. ### Claim 2 (depends on 1) The method of claim 1, wherein the status change indication corresponds to a least one of a suspended status or an out-of-service status for the at least one of the UDM function or the UDR located in the second segment of the first core network. ### Claim 3 (depends on 1) The method of claim 1, wherein the subscribing comprises: determining, by the first NRF, that the first core network is a segmented network; and transmitting, by the first NRF and to the second NRF and in response to determining that the first core network is a segmented network, a subscribe message, wherein the subscribe message identifies at least one of the UDM function or UDR. ### Claim 4 (depends on 1) The method of claim 1, further comprising: receiving, at the first NRF, at least one of a UDM function or UDR discovery request from a network function (NF), wherein the UDM function or UDR discovery request is associated with subscriber information stored in the UDM function or UDR located in the second segment of the first core network; and responding, by the first NRF, to the discovery request. ### Claim 5 (depends on 4) The method of claim 4, wherein the responding comprises: transmitting, by the first NRF, information associated with a subscriber without accessing the second NRF. ### Claim 6 (depends on 1) The method of claim 1, wherein the subscribing comprises: transmitting, by the first NRF and to the second NRF, a subscribe message, wherein the subscribe message identifies at least one of the UDM function or UDR; and receiving, by the first NRF and from the second NRF, at least one of UDM or UDR information associated with the at least one of the UDM function or UDR located in the second segment of the first core network. ### Claim 7 (depends on 6) The method of claim 6, wherein the at least one of UDM or UDR information comprises at least one of registration or status information. ### Claim 8 (depends on 1) The method of claim 1, further comprising: receiving, at the first NRF, at least one of a UDM function or UDR discovery request from a network function (NF), wherein the UDM function or UDR discovery request is associated with subscriber information stored in the UDM function or UDR located in the second segment of the first core network, and wherein the NF comprises at least one of an access and mobility management function, a session management function, a policy control function or a network exposure function, and wherein the discovery request includes a subscriber permanent identifier. ### Claim 9 (depends on 1) The method of claim 1, further comprising: subscribing, by NRFs located in other segments of the first core network, to UDM function or UDR event information; and propagating, by each of the NRFs located in the other segments of the first core network, the UDM function and UDR event information to other ones of the NRFs. ### Claim 10 (depends on 1) The method of claim 1, further comprising: transmitting, by a first network function, a discovery request including a subscriber permanent identifier (SUPI) to the first NRF, wherein the first NRF is an NRF that is located physically closest to the first network function as compared to other NRFs, and the SUPI is associated with subscriber information stored in the second segment of the first core network. ### Claim 11 A system, comprising: a first network repository function (NRF) located in a first segment of a first core network, wherein the first NRF includes at least a first processor; a second NRF located in a second segment of the first core network, wherein the second NRF includes at least a second processor, and wherein the first core network is managed by a single telecommunications service provider and the first and second segments of the first core network are managed by the single telecommunications service provider; and at least one of a unified data management (UDM) function or a unified data repository (UDR) located in each of the first segment and second segment of the first core network, wherein the first NRF is configured to: subscribe to event information associated with at least one of a unified data management (UDM) function or a unified data repository (UDR) located in a second segment of the first core network, and receive, from the second NRF, at least one of UDM or UDR information associated with the at least one of the UDM function or UDR located in the second segment of the first core network, and wherein the second NRF is configured to: receive a status change indication associated with at least one of the UDM function or UDR located in the second segment of the first core network, and forward, to the first NRF, a notification message identifying the status change. ### Claim 12 (depends on 11) The system of claim 11, wherein the status change indication corresponds to a least one of a suspended status or an out-of-service status for the at least one of the UDM function or the UDR located in the second segment of the first core network. ### Claim 13 (depends on 11) The system of claim 11, wherein when subscribing, the first NRF is configured to: determine that the first core network is a segmented network, and transmit, to the second NRF, and in response to determining that the first core network is a segmented network, a subscribe message, wherein the subscribe message identifies at least one of the UDM function or UDR. ### Claim 14 (depends on 11) The system of claim 11, wherein the first NRF is further configured to: receive at least one of a UDM function or UDR discovery request from a network function (NF), wherein the UDM function or UDR discovery request is associated with subscriber information stored in the UDM function or UDR located in the second segment of the first core network, and respond to the discovery request without accessing the second NRF. ### Claim 15 (depends on 11) The system of claim 11, wherein when receiving at least one of UDM function or UDR information, the first NRF is configured to: receive, from the second NRF at least one of UDM or UDR registration or status information. ### Claim 16 (depends on 11) The system of claim 11, further comprising: a first network function configured to: transmit a discovery request including a subscriber permanent identifier (SUPI) to the first NRF, wherein the first NRF is an NRF that is located physically closest to the first network function as compared to other NRFs, and the SUPI is associated with subscriber information stored in the second segment of the first core network. ### Claim 17 A non-transitory computer-readable medium having stored thereon sequences of instructions which, when executed by at least one processor associated with a network repository function (NRF) located in a first segment of a first core network, cause the at least one processor to: subscribe to event information associated with a first network function (NF) located in a second segment of the first core network; receive, from a second NRF located in the second segment of the first core network, at least one of unified data management (UDM) function or unified data repository (UDR) information associated with the at least one of a UDM function or a UDR located in the second segment of the first core network, wherein the first core network is managed by a single telecommunications service provider and the first and second segments of the first core network are managed by the single telecommunications service provider; and receive, from the second NRF, a status change message associated with at least one of the UDM function or UDR located in the second segment of the first core network. ### Claim 18 (depends on 17) The non-transitory computer-readable medium of claim 17, wherein the status change message indicates at least one of a suspended status or an out-of-service status for the at least one of the UDM function or UDR located in the second segment of the first core network. ### Claim 19 (depends on 17) The non-transitory computer-readable medium of claim 17, wherein the instructions further cause the processor to: determine that the first core network is a segmented network; and transmit, to the second NRF, and in response to determining that the first core network is a segmented network, a subscribe message, wherein the subscribe message identifies at least one of the UDM function or UDR. ### Claim 20 (depends on 17) The non-transitory computer-readable medium of claim 17, wherein the instructions further cause the at least one processor to: receive a registration message from at least one of the UDM function or UDR located in the first segment of the first core network; and forward, to the second NRF, a notification message identifying the UDM function or UDR located in the first segment of the first core network.