Update user equipment parameters

Abstract

The present disclosure relates to updating user equipment parameters. A user equipment (UE) may perform a UE parameter update (UPU) procedure or a roaming guidance (SoR) procedure based on information received from a home public land mobile network (HPLMN). The UE receives an update container including updated parameters of the UE and a counter value associated with the update container from a network component, compares the counter value with a stored value, and performs an action related to the update container based at least on the comparison of the counter value with the stored value.

Description

Background Art

[0001] 5G New Radio (NR) wireless communications support the updating of user equipment (UE) parameters by the Home PLMN (HPLMN). The HPLMN updates parameters based on the network provider's policy. For example, according to current 3GPP standards, parameters such as updated default configured Network Slice Selection Assistance Information (NSSAI), updated Route ID data, and / or Steering of Roaming (SoR) lists can be updated on the UE by the HPLMN. However, there are scenarios where UE parameters may not be updated correctly. Summary of the Invention

[0002] Some example embodiments relate to a user equipment (UE) having a transceiver and one or more processors communicatively coupled to the transceiver. The one or more processors are configured to perform operations. The operations include: receiving an update container including updated parameters of the UE and a counter value associated with the update container from a network component; comparing the counter value with a stored value; and performing an action related to the update container based at least on the comparison of the counter value with the stored value.

[0003] Other example embodiments relate to a baseband processor configured to perform operations including: receiving, from a network component, an update container including updated parameters for a user equipment (UE) and a counter value associated with the update container; comparing the counter value with a stored value; and performing an action related to the update container based at least on the comparison of the counter value with the stored value.

[0004] Another exemplary embodiment relates to a network component that implements a unified data management (UDM) function of a core network. The network component includes one or more processors configured to perform operations. The operations include: determining that an old routing indicator being used by a user equipment (UE) should be updated to a new routing indicator, wherein the old routing indicator is associated with an old unified data management (UDM) instance and an old authentication server function (AUSF) instance, and the new routing indicator is associated with a new UDM instance and a new AUSF instance; protecting the new routing indicator, wherein protecting the new routing indicator includes determining a UE parameter update (UPU) counter based on an AUSF key; granting access rights to UE subscription information to the new UDM instance and the new AUSF instance by the old UDM instance and the old AUSF instance; sending a transmission including the new routing indicator and an acknowledgment (ACK) request indicator to an access and mobility management function (AMF) of the core network; and forwarding the transmission to the UE. BRIEF DESCRIPTION OF THE DRAWINGS

[0005] Figure 1 Exemplary network arrangements are shown according to various exemplary embodiments.

[0006] Figure 2 An exemplary UE according to various exemplary embodiments is shown.

[0007] Figure 3 is a signaling diagram illustrating a UE parameter update (UPU) procedure according to various exemplary embodiments.

[0008] Figure 4 is a signaling diagram illustrating a UPU procedure according to various exemplary embodiments.

[0009] Figure 5 is a signaling diagram illustrating a routing indicator update procedure according to various exemplary embodiments.

[0010] Figure 6 is a signaling diagram illustrating a Guide to Roaming (SoR) list update procedure according to various exemplary embodiments.

[0011] Figure 7 is a signaling diagram illustrating a SoR list update procedure according to various exemplary embodiments. DETAILED DESCRIPTION

[0012] The exemplary embodiments may be further understood with reference to the following description and associated drawings, wherein similar elements have the same reference numerals. The exemplary embodiments describe a method for updating parameters of user equipment (UE) in a 5G New Radio (NR) network.

[0013] The exemplary embodiments are described with reference to a network including a 5G New Radio NR radio access technology (RAT). However, the exemplary embodiments can be implemented in other types of networks using the principles described herein.

[0014] The exemplary embodiments are also described with reference to a UE. However, the use of a UE is for illustrative purposes only. The exemplary embodiments can be utilized with any electronic component that can establish a connection to a network and is configured with hardware, software, and / or firmware for exchanging information and data with the network. Therefore, the term UE as used herein is intended to represent any electronic component.

[0015] As mentioned above, the Home Public Land Mobile Network (HPLMN) may need to update parameters of the UE. Current 3GPP standards provide a method for performing a UE parameter update (UPU) by the HPLMN to update parameters such as, for example, updated default configured Network Slice Selection Assistance Information (NSSAI), updated Route ID data and / or Steering of Roaming (SoR) lists. However, the current standards do not address the issue of the network being unable to reach the UE or the UE being unable to send an acknowledgement (ACK) back to the network due to, for example, a Radio Link Failure (RLF) event. Another undesirable scenario that may also occur and is not addressed by the current standards is when the UE encounters a Tracking Area (TA) change to a TA outside the registration area during the UPU procedure, which would require initiation of a Registration Request procedure.

[0016] If the routing indicator change is not handled correctly by the Unified Data Management (UDM) of the UE and the network, the UE may use the old routing indicator in the Subscription Hidden Identifier (SUCI) sent to the Access and Mobility Management Function (AMF) of the network. Since the network considers the new routing indicator (provided in the UPU procedure) as a valid routing indicator, service to the UE may be denied because the AMF may not be able to select the correct Authentication Server Function (AUSF) and UDM instance (e.g., private key or home network private key) required to fetch the UE subscription information related to the authentication process, subscribed slice information, or other important parameters related to the UE's subscription information. If the default configured NSSAI is not updated correctly in the UE, the UE may continue to use the old default configured NSSAI and will not receive service on the newly configured single NSSAI.

[0017] According to some exemplary embodiments, the UPU procedure may include utilizing a timer to track the completion of the UPU acquisition if the UDM requests an ACK from the UE. In these exemplary embodiments, the UDM will retransmit the UPU container including the updated routing indicator and / or the updated default NSSAI.

[0018] According to other exemplary embodiments, if the AMF cannot reach the UE, the UPU procedure may request the AMF to notify the UDM of the communication failure. In these exemplary embodiments, the UDM requests the AMF to notify the UDM of any subsequent UE connection state changes so that the UDM can re-initiate the UPU procedure.

[0019] According to another exemplary embodiment, the UPU procedure for routing indicator change may alternatively grant access to UE subscription information to both the new and old UDM and AUSF instances. If the AMF subsequently contacts the new UDM instance for UE context information, the UE subscription information is deleted from the old UDM and AUSF instances. However, if the AMF contacts the old UDM instance for UE context information, the old UDM resends the UPU container, which includes the routing indicator change.

[0020] Another issue that the current 3GPP standard cannot address when the SoR list update procedure fails is that the UE may not be updated with the preferred PLMN and access technology list provided by the home network. As a result, the UE may experience less than desirable conditions when roaming, and the network provider may incur additional costs.

[0021] According to some exemplary embodiments, the SoR list update process may include tracking the completion of the SoR list update acquisition using a timer if the UDM requests an ACK from the UE. In these exemplary embodiments, the UDM will retransmit the SoR container including the updated PLMN list.

[0022] According to some exemplary embodiments, if the AMF cannot reach the UE, the SoR List Update procedure may request the AMF to notify the UDM of the communication failure. In these exemplary embodiments, the UDM requests the AMF to notify the UDM of any subsequent UE connection state changes so that the UDM can re-initiate the SoR List Update procedure.

[0023] Figure 1 An exemplary network arrangement 100 according to various exemplary embodiments is shown. The exemplary network arrangement 100 includes a UE 110. It should be noted that any number of UEs may be used in the network arrangement 100. Those skilled in the art will appreciate that the UE 110 may alternatively be any type of electronic component configured to communicate via a network, such as a mobile phone, tablet computer, desktop computer, smartphone, phablet, embedded device, wearable device, Internet of Things (IoT) device, etc. It should also be appreciated that an actual network arrangement may include any number of UEs used by any number of users. Therefore, for illustrative purposes, only an example with a single UE 110 is provided.

[0024] UE 110 can be configured to communicate with one or more networks. In the example of network configuration 100, the networks with which UE 110 can wirelessly communicate are 5G New Radio (NR) radio access network (5G NR-RAN) 120, LTE radio access network (LTE-RAN) 122, and wireless local area network (WLAN) 124. However, it should be understood that UE 110 can also communicate with other types of networks, and UE 110 can also communicate with networks via wired connections. Thus, UE 110 can include a 5G NR chipset for communicating with 5G NR-RAN 120, an LTE chipset for communicating with LTE-RAN 122, and an ISM chipset for communicating with WLAN 124.

[0025] 5G NR-RAN 120 and LTE-RAN 122 may be part of a cellular network that may be deployed by a cellular provider (e.g., Verizon, AT&T, T-Mobile, etc.). These networks 120, 122 may include, for example, cells or base stations (NodeB, eNodeB, HeNB, eNBS, gNB, gNodeB, macrocell base stations, microcell base stations, small cell base stations, femtocell base stations, etc.) configured to send and receive traffic from UEs equipped with appropriate cellular chipsets. WLAN 124 may include any type of wireless local area network (WiFi, hotspot, IEEE 802.11x network, etc.).

[0026] UE 110 may connect to 5G NR-RAN 120 via gNB 120A and / or gNB 120B. During operation, UE 110 may be within range of multiple gNBs. Thus, simultaneously or alternatively, UE 110 may connect to 5G NR-RAN 120 via gNBs 120A and 120B. Furthermore, UE 110 may communicate with eNB 122A of LTE-RAN 122 to transmit and receive control information for downlink and / or uplink synchronization of the connection with respect to 5G NR-RAN 120.

[0027] Those skilled in the art will appreciate that any relevant procedures may be performed for UE 110 to connect to 5G NR-RAN 120. For example, as described above, 5G NR-RAN 120 may be associated with a particular cellular provider, where UE 110 and / or its user has agreement and credential information (e.g., stored on a SIM card). Upon detecting the presence of 5G NR-RAN 120, UE 110 may transmit corresponding credential information in order to associate with 5G NR-RAN 120. More specifically, UE 110 may associate with a particular base station (e.g., gNB 120A of 5G NR-RAN 120).

[0028] In addition to networks 120, 122, and 124, network arrangement 100 also includes a cellular core network 130, the Internet 140, an IP Multimedia Subsystem (IMS) 150, and a network service backbone 160. Cellular core network 130 also manages traffic flowing between the cellular network and the Internet 140. Cellular core network 130 can be viewed as an interconnected collection of components that manage the operation and traffic of the cellular network. In this example, the components include access and mobility management function (AMF) 131, authentication server function (AUSF) 132, and unified data management (UDM) 133. However, a practical cellular core network may include various other components that perform any of a variety of different functions.

[0029] The AMF 131 performs operations related to mobility management, such as, but not limited to, paging, non-access stratum (NAS) management, and registration procedure management between the UE 110 and the cellular core network 130. Reference to a single AMF 131 is for illustrative purposes only, and an actual network arrangement may include any appropriate number of AMFs.

[0030] AUSF 132 is responsible for UE authentication. The AUSF determines whether the UE is authorized to use services provided by the home / serving network. AUSF 132 retrieves information from UDM 133, on which it performs UE authentication. When sending a UPU container or SoR container to the UE, AUSF 132 also provides integrity protection services to UDM 133. This is used so that both the UE and the network can confirm that the message has not been tampered with by the serving network.

[0031] When sending a UPU container, AUSF 132 sends UPU-MAC-IAUSF and CounterUPU. If UDM 133 sends an ACK indication to AUSF 132, UPU-XMAC-IUE is sent. When sending a SoR container, AUSF 132 sends SoR-MAC-IAUSF and CounterSOR. If UDM 133 sends an ACK indication to AUSF 132, SOR-XMAC-IUE is sent. Each of these operations is described in more detail below. In summary, AUSF 132 sends parameters to UDM 133 for integrity protection of UPU data or SoR data sent by UDM 133 to the UE.

[0032] UDM 133 may process subscription-related information to support handling of communication sessions and may store subscription data for UE 110. For example, subscription data may be transferred between UDM 133 and AMF 131. The UDM may include a front end (FE) responsible for handling credentials, location management, subscription management, and the like. Several different front ends may provide services to the same user in different transactions. The UDM-FE accesses subscription information stored in a unified data repository (not shown) and performs authentication credential processing, user identification processing, access authorization, registration / mobility management, and subscription management.

[0033] The IMS 150 can be generally described as an architecture for delivering multimedia services to the UE 110 using the IP protocol. The IMS 150 can communicate with the cellular core network 130 and the Internet 140 to provide multimedia services to the UE 110. The network service backbone 160 communicates directly or indirectly with the Internet 140 and the cellular core network 130. The network service backbone 160 can be generally described as a set of components (e.g., servers, network storage arrangements, etc.) that implement a set of services that can be used to extend the functionality of the UE 110 to communicate with various networks.

[0034] Figure 2 An exemplary UE 110 is shown according to various exemplary embodiments. Figure 1 10 is described with reference to the network arrangement 100 of FIG. For the purposes of this discussion, the UE 110 may be considered a reduced capability (RedCap) UE. However, it should be noted that the UE 110 may represent any electronic device and may include a processor 205, a memory arrangement 210, a display device 215, an input / output (I / O) device 220, a transceiver 225, and other components 230. The other components 230 may include, for example, an audio input device, an audio output device, a battery providing a limited power source, a data acquisition device, ports for electrically connecting the UE 110 to other electronic devices, one or more antenna panels, and the like. For example, the UE 110 may be coupled to industrial equipment via one or more ports.

[0035] The processor 205 may be configured to execute multiple engines of the UE 110. For example, the engines may include an update management engine 235. As will be described in more detail below, the update management engine 235 may perform various operations related to the update process, such as, for example, processing a UPU or SoR container received from the network, and applying updates in the container or updating a Universal Subscriber Identity Module (USIM) Elementary File (EF).

[0036] The engine described above as an application (e.g., a program) executed by the processor 205 is merely exemplary. The functionality associated with the engine may also be represented as a separate, integrated component of the UE 110, or may be a modular component coupled to the UE 110, such as an integrated circuit with or without firmware. For example, an integrated circuit may include input circuits for receiving signals and processing circuits for processing signals and other information. The engine may also be embodied as one application or multiple separate applications. In addition, in some UEs, the functionality described for the processor 205 is shared between two or more processors, such as a baseband processor and an application processor. The exemplary embodiments may be implemented in any of these or other configurations of the UE.

[0037] The memory arrangement 210 may be a hardware component configured to store data related to operations performed by the UE 110. The display device 215 may be a hardware component configured to display data to a user, and the I / O device 220 may be a hardware component that enables user input. The display device 215 and the I / O device 220 may be separate components or may be integrated together (such as a touch screen). The transceiver 225 may be a hardware component configured to establish a connection with the 5G NR-RAN 120, the LTE-RAN 122, the WLAN 124, etc. Thus, the transceiver 225 may operate on multiple different frequencies or channels (e.g., a continuous set of frequencies).

[0038] Figure 3 FIG3 is a signaling diagram 300 illustrating an update process according to various exemplary embodiments. At 305, UDM 133 determines that one or more parameters of UE 110 should be updated. In some embodiments, the one or more parameters may be an updated routing indicator and / or an updated default configured NSSAI. The routing indicator indicates to UE 110 that the UE should switch to a new UDM instance and a new AMF instance. At 310, the UDM sends UPU data (e.g., the updated routing indicator and / or the updated default configured NSSAI) to AUSF 132 along with a subscription permanent identifier (SUPI) and an indication of whether an acknowledgment (ACK) is requested from UE 110. For the purposes of this description, it will be assumed that UDM 133 requests an ACK. However, it should be noted that in some embodiments, an ACK is not required. At 315, AUSF 132 transmits a response to UDM 133 containing UPU-MAC-I_AUSF, UPU-XMAC-I_UE, and Counter_UPU.

[0039] At 320, UDM 133 starts a timer to track the receipt of the UPU ACK. If the timer expires before UDM 133 receives the ACK, UDM 133 retries the UPU procedure. In some embodiments, if UDM 133 detects a change of AMF while the UPU procedure is in progress (e.g., UE 110 initiates a registration request at a new AMF), UDM 133 may initiate the UPU procedure after AMF 131 notifies UDM 133 of the updated location of UE 110. However, if the AMF contacts the new UDM instance, the UPU procedure is considered complete because UE 110 has successfully migrated to the new UDM instance.

[0040] At 325, UDM 133 notifies AMF 131 of the parameter change via Nudm_SDM_Nofication. This includes the updated parameters and an indication of whether UE 110 should send an ACK. If AMF 131 cannot communicate with UE 110, then at 330, AMF 131 discards the Nudm_SDM_Nofication. If, at 335, UDM 133 determines that the timer has expired or that UE 110 has camped on a new AMF, then at 340, UDM 133 initiates a retransmission of the UPU container (Nudm_SDM_Nofication). If, at 345, UDM 133 determines that the number of retransmissions is equal to a predetermined maximum number of retransmissions and an ACK has not been received from UE 110, then UDM 133 considers the routing indicator update and / or the default configured NSSAI update pending. In this case, the network considers the old routing indicator as active until AMF 131 contacts UDM 133 again. In case of the default configured NSSAI, UDM 133 will wait for AMF 131 to update the location of UE 110.

[0041] However, if the AMF 131 is able to communicate with the UE 110, then at 350, the AMF 131 sends a DL NAS TRANSPORT message containing the UPU container to the UE 110. It should be noted that if the AMF 131 is able to communicate with the UE 110, this message may be sent after 325 (original transmission of the UPU container) or 340 (retransmission of the UPU container).

[0042] At 355, UE 110 compares the received Counter_UPU with a stored value in UE 110. If the values ​​are the same and an ACK is requested, UE 110 sends an ACK to the network at 360 after integrity protecting the ACK according to 3GPP specifications and including the UPU-MAC-IUE in the UL NAS TRANSPORT. No further processing of the UPU container occurs. If the values ​​are the same and an ACK is not requested, UE 110 does not further process the UPU container without sending an ACK.

[0043] If the received Counter_UPU is different from the one held at UE 110 and is a higher value, UE 110 processes the UPU container according to the 3GPP specifications. For example, UE 110 calculates the UPU-MAC-IAUSF and compares it with the UPU-MAC-IAUSF received from the network. If they are the same, UE 110 proceeds to process the UPU container at 360 and, if necessary, sends an ACK.

[0044] At 365, the AMF 131 transmits a Nudm_SDM_Info message containing the UPU-MAC-I_UE to the UDM 133. At 370, the UDM 133 compares the UPU-MAC-I_UE received from the AMF 131 at 365 with the UPU-XMAC-I_UE received from the AUSF 132 at 315. If the UPU-MAC-I_UE and the UPU-XMAC-I_UE are the same, the UDM 133 considers the UPU procedure to be successfully completed.

[0045] If, after verifying the UPU-MAC-I_AUSF at 355, the UE 110 is unable to transmit an ACK due to, for example, RLF, then the UDM 133 does not know whether the UE 110 received the UPU container and / or successfully processed the UPU. In some embodiments, the UDM 133 initiates a retransmission of the UPU container (Nudm_SDM_Nofication), as described above at 335. However, if the maximum number of retransmissions has been reached and the UPU procedure is triggered only for a routing indicator change, the UDM 133 maintains the UE subscription context in both the old UDM instance (133) and the new UDM instance. The purpose of this functionality is that, from the perspective of the UDM 133, the failure to receive an ACK could mean that the UE 110 never received the UPU container or that the UE 110 received the UPU container and successfully processed it but was unable to send an ACK. Therefore, it is advantageous to maintain the UE subscription context in both the old and new UDM instances in the event that an ACK is not received. If the maximum number of retransmissions has been reached and the UPU includes a default slice configuration change, then no changes are made in the UDM instance and the specific UDM instance tracks whether the UPU container has been received by UE 110. However, if UE 110 receives and processes the UPU container, and UE 110 subsequently receives a retransmission of the UPU container with the same Counter_UPU, UE 110 may send an ACK, as described above, without processing the retransmitted UPU container.

[0046] In some embodiments, if between retransmissions (340) or after determining that UE 110 is unreachable, AMF 131 contacts the old UDM instance to fetch the UE subscription context, then UDM 133 may re-initiate the routing indicator change procedure after completing the registration procedure. In some embodiments, if between retransmissions (340) or after determining that UE 110 is unreachable, AMF 131 contacts the new UDM instance to fetch the UE subscription context, then the new UDM may trigger the deletion of the UE subscription context from the old UDM (133) and consider the UPU update procedure successfully completed. In some embodiments, if UDM 133 is notified by AMF 131 of the change in location of UE 110 (Nudm_UECM_Registration) and the registration procedure is successful, then the UDM 133 instance stops any retransmissions of the UPU container (340) and generates a new UPU container using the new AUSF key (K_AUSF) and the new Counter_UPU.

[0047] Figure 4FIG4 is a signaling diagram 400 illustrating a UPU procedure according to various exemplary embodiments. Since 405-415 are identical to 305-315, and 460-480 are identical to 350-370, the descriptions of 405-415 and 460-480 will be omitted for brevity. At 420, UDM 133 starts a timer to track the delivery of the UPU container to UE 110. Similar to 325 discussed above, at 425, UDM 133 notifies AMF 131 of the parameter change using Nudm_SDM_Notification.

[0048] In some embodiments, if AMF 131 cannot communicate with UE 110, then at 430, AMF 131 may attempt to initiate a network-triggered service request procedure by paging UE 110. However, if UE 110 is unreachable, then at 435, AMF 131 notifies UDM 133 that the transmission of the UPU container has failed. In this case, at 440, UDM 133 may register with AMF 131 to be notified of any UE connection state changes, so that if UE 110 reconnects to the network, UDM 133 will be notified and will re-initiate the UPU procedure. Alternatively, if UE 110 triggers registration on a new AMF, UDM 133 triggers the transmission of the UPU container to UE 110 using the same Counter_UPU after the REGREQUEST procedure is completed.

[0049] If UDM 133 does not receive a failure notification from AMF 131, and if, at 445, UDM 133 determines that the timer has expired or UE 110 has camped on a new AMF, then at 450, UDM 133 initiates a retransmission of the UPU container (Nudm_SDM_Nofication). If, at 455, UDM 133 determines that the number of retransmissions is equal to the predetermined maximum number of retransmissions and an ACK has still not been received from UE 110, then UDM 133 waits for a trigger from AMF 131 to update the UE location, which will subsequently trigger the UPU procedure. For the routing indicator change case, until such a trigger is received from AMF 131, UDM 133 will grant access to the UE subscription context to both the old and new UDM instances. For the default configured slicing case, the serving UDM instance keeps the procedure pending until AMF 131 fetches the UE subscription context or AMF 131 updates the UE 110 location to UDM 133.

[0050] For the routing indicator change case, if the AMF 131 cannot communicate with the UE 110 due to, for example, RLF and the UPU container is not transferred to the UE 110, then in some embodiments, both the old and new UDM and AUSF instances have access to the subscription context of the UE 110 and the UPU procedure is considered pending. For the default configured slicing case, the serving UDM instance keeps the procedure pending until the AMF 131 fetches the UE subscription context or the AMF 131 updates the UE 110 location to the UDM 133.

[0051] If, after verifying the UPU-MAC-I_AUSF at 465, UE 110 is unable to transmit an ACK due to, for example, RLF, then UDM 133 does not know whether UE 110 received the UPU container and / or successfully processed the UPU. In some embodiments, for a routing indicator change, UE 110 may send a new routing indicator with SUCI to AMF 131, which in turn selects a new AUSF instance and a new UDM instance for the UE's subscription context. Consequently, the new UDM instance requests the old UDM instance to remove access rights to the UE's subscription context. For the default configured NSSAI, UDM 133 considers the UPU procedure pending. If the new routing indicator indicates default access, then access rights to the UE's subscription context do not need to be maintained in both the old and new UDM instances.

[0052] In some embodiments, if the UE 110 registers with a new AMF and, as part of the registration process, the new AMF contacts the UDM 133 for information about the UE, the UDM may trigger any pending UPU procedures. In some embodiments, if the UDM 133 receives a trigger to update the location of the UE 110 (Nudm_UECM_Registration), the UDM 133 stops any pending retransmissions of the UPU container and re-initiates the UPU procedure by requesting AUSF 132 protection of the UPU data using a newly generated K_AUSF (using -Nausf_UPUProtection and a reinitialized CounterUPU value).

[0053] Figure 55 is a signaling diagram 500 illustrating a routing indicator update procedure according to various exemplary embodiments. At 505, the UDM 133 determines that a routing indicator update should be performed at the UE 110. Since 510-515 are the same as 310-315, and 530-550 are the same as 350-370, the descriptions of 505-515 and 530-550 will be omitted here for the sake of brevity. At 520, accessibility to the UE's subscription context is provided to the new UDM instance and the new AUSF instance, such that both the old and new UDM and AUSF instances maintain accessibility to the UE's subscription context. Similar to 325 discussed above, at 525, the UDM 133 notifies the AMF 131 of the change to the routing indicator via Nudm_SDM_Nofication.

[0054] If the serving AMF contacts the old UDM instance for authentication, then at 555a, the UDM 133 determines to repeat 510-550 using the new security context (e.g., new K_AUSF) and Counter_UPU. However, if the serving AMF contacts the new UDM instance, then at 555b, the new UDM instance requests to delete the UE subscription context from the old UDM instance and the old AUSF instance.

[0055] If, after verifying the UPU-MAC-I_AUSF at 465, the UE 110 fails to transmit an ACK due to, for example, RLF, the UDM 133 does not know whether the UE 110 received the UPU container and / or successfully processed the UPU. In some embodiments, for a routing indicator change, the UE 110 may send a new routing indicator with the SUCI to the AMF, which in turn selects a new AUSF instance and a new UDM instance to take the UE's subscription context. Therefore, the new UDM instance requests the old UDM instance to remove access to the UE's subscription context.

[0056] Figure 6FIG6 is a signaling diagram 600 illustrating a Steering of Roaming (SoR) list update procedure according to various exemplary embodiments. At 605, UDM 133 determines that a SoR list update is necessary. In some embodiments, the SoR list update updates the list of operator-controlled PLMNs with access technologies stored on UE 110. At 610, UDM 133 transmits the SoR data to AUSF 132 along with the SUPI and an indication of whether an acknowledgment (ACK) is requested from UE 110. For the purposes of this description, it will be assumed that UDM 133 requests an ACK. However, it should be noted that in some embodiments, an ACK is not required. At 615, AUSF 132 sends a response to UDM 133 containing SoR-MAC-I_AUSF, SoR-XMAC-I_UE, and Counter_SoR.

[0057] At 620, UDM 133 starts a timer to track the receipt of the SoR ACK. If the timer expires before UDM 133 receives the ACK, UDM 133 retries the SoR update procedure. In some embodiments, if UDM 133 detects a change of AMF while the SoR update procedure is in progress (e.g., UE 110 initiates a registration request at a new AMF), UDM 133 may initiate the SoR update procedure as part of the registration request procedure, after AMF 131 fetches the UE subscription information from UDM 133, after the registration request procedure is completed, or after AMF 131 notifies UDM 133 of the updated location of UE 110.

[0058] At 625, UDM 133 notifies AMF 131 of the parameter change via Nudm_SDM_Nofication. This includes the updated SoR list and an indication of whether the UE needs to send an ACK. If AMF 131 cannot communicate with UE 110, then at 630, AMF 131 discards the Nudm_SDM_Nofication. If, at 635, UDM 133 determines that the timer has expired or that UE 110 has camped on a new AMF, then at 640, UDM 133 initiates a retransmission of the SoR container (Nudm_SDM_Nofication). If, at 645, UDM 133 determines that the number of retransmissions is equal to a predetermined maximum number of retransmissions and an ACK has not yet been received from UE 110, then UDM 133 considers the SoR update procedure pending until the serving AMF contacts UDM 133 to update the location of UE 110.

[0059] However, if AMF 131 is able to communicate with UE 110, then at 650, AMF 131 sends a DL NAS TRANSPORT message containing the UPU container to UE 110. Note that if AMF 131 is able to communicate with UE 110, this message may be sent after 625 (original transmission of the SoR container) or 640 (retransmission of the SoR container). At 655, UE 110 verifies the SoR-MAC-I-AUSF according to 3GPP specifications by comparing the Counter_SoR with the previously received Counter_SoR to confirm that the SoR container is from the HPLMN. If the received Counter_SoR value is the same as the stored value on UE 110 and an ACK is requested, UE 110 sends an ACK to the network at 660 after integrity protecting the ACK according to 3GPP specifications and including the SoR-MAC-IUE in the UL NAS TRANSPORT. UE 110 will not further process the SoR container. If the received Counter_SoR value is the same as the stored value on UE 110, and an ACK is not requested, UE 110 does not process the SoR container further and does not send an ACK.

[0060] If the received Counter_SoR is different from the one maintained at UE 110 and is a higher value, UE 110 processes the SoR container according to the 3GPP specifications. For example, UE 110 calculates SoR-MAC-IAUSF and compares it with the value received from the network. If they are the same, UE 110 proceeds with processing the SoR container and sends an ACK (if requested) at 660.

[0061] At 665, the AMF 131 sends a Nudm_SDM_Info message containing the SoR-MAC-I_UE to the UDM 133. At 670, the UDM 133 compares the SoR-MAC-I_UE received from the AMF 131 at 665 with the SoR-XMAC-I_UE received from the AUSF 132 at 615. If the SoR-MAC-I_UE and the SoR-XMAC-I_UE are the same, the UDM 133 considers the SoR procedure completed successfully.

[0062] If, after verifying the SoR-MAC-I_AUSF at 655, the UE 110 is unable to transmit an ACK due to, for example, RLF, then the UDM 133 does not know whether the UE 110 received the SoR container and / or successfully processed the SoR update. In some embodiments, the UDM 133 initiates a retransmission of the SoR container (Nudm_SDM_Nofication), as described above at 635. However, if the UE 110 receives and processes the SoR container, and the UE 110 subsequently receives a retransmission of the SoR container with the same Counter_SoR, the UE 110 may send an ACK, as described above, without processing the retransmitted SoR container.

[0063] In some embodiments, if the serving AMF contacts UDM 133 to update the location of UE 110 between retransmissions (640) or after determining that UE 110 is unreachable, UDM 133 may re-initiate the pending SoR procedure during or after the registration procedure is completed. In some embodiments, the SoR container may be included in the Registration Accept message sent to UE 110. In some embodiments, if UDM 133 is notified of the location change of UE 110 by the serving AMF (Nudm_UECM_Registration) and the registration procedure is successful, the UDM 133 instance stops any pending retransmissions of the SoR container (640) and requests AUSF 132 to re-provision integrity protection parameters (e.g., MAC-I and Counter_SoR) based on the newly generated K_AUSF and the reinitialized Counter_SoR value.

[0064] Figure 7 FIG7 is a signaling diagram 700 illustrating a SoR list update procedure according to various exemplary embodiments. Since 705-715 are identical to 605-615, and 760-780 are identical to 650-670, the descriptions of 705-715 and 760-780 will be omitted for brevity. At 720, UDM 133 starts a timer to track the delivery of the SoR container to UE 110. Similar to 625 discussed above, at 625, UDM 133 notifies AMF 131 of the change to the SoR list via Nudm_SDM_Notification.

[0065] In some embodiments, if AMF 131 cannot communicate with UE 110, then at 730, AMF 131 may attempt to initiate a network-triggered service request procedure by paging UE 110. However, if UE 110 is unreachable, then at 735, AMF 131 notifies UDM 133 that the transfer of the SoR container has failed. In this case, at 740, UDM 133 may register with AMF 131 to be notified of any UE connection state changes, so that if UE 110 reconnects to the network, UDM 133 will be notified and will re-initiate the SoR procedure. Alternatively, if UE 110 triggers registration on a new AMF, UDM 133 restarts the SoR procedure using the same Counter_SoR during or after the registration procedure is completed.

[0066] If UDM 133 does not receive a failure notification from AMF 131, and if, at 745, UDM 133 determines that the timer has expired or UE 110 has camped on a new AMF, then UDM 133 initiates a retransmission of the SoR container (Nudm_SDM_Nofication) at 750. If, at 755, UDM 133 determines that the number of retransmissions is equal to the predetermined maximum number of retransmissions and still has not received an ACK from UE 110, then UDM 133 waits for a trigger from AMF 131 to update the UE 110 location or fetch the UE 110 subscription information, which will then trigger the SoR procedure.

[0067] If, after verifying UPU-MAC-I_AUSF at 765, UE 110 fails to transmit an ACK due to, for example, RLF, then UDM 133 does not know whether UE 110 received the SoR container and / or successfully processed the SoR update. In some embodiments, UDM 133 considers the SoR update procedure pending.

[0068] In some embodiments, if UE 110 registers with a new AMF and, as part of the registration process, the new AMF contacts UDM 133 for information about the UE, the UDM may trigger any pending SoR procedures. In some embodiments, if UDM 133 receives a trigger (Nudm_UECM_Registration) to update the location of UE 110, UDM 133 stops any pending retransmissions of the SoR container and requests AUSF 132 to re-provision integrity protection parameters (e.g., MAC-I and Counter_SoR) based on a newly generated K_AUSF and a reinitialized Counter_SoR value.

[0069] Those skilled in the art will appreciate that the exemplary embodiments described above can be implemented with any suitable software configuration or hardware configuration or combination thereof. Exemplary hardware platforms for implementing the exemplary embodiments may include, for example, Intel x86-based platforms with compatible operating systems, ARM-based microprocessors, Windows OS, Mac platforms and MAC OS, mobile devices with operating systems such as iOS, Android, etc. In other examples, the exemplary embodiments of the above methods may be embodied as a program comprising lines of code stored on a non-transitory computer-readable storage medium, which, when compiled, can be executed on a processor or microprocessor.

[0070] Although this patent application describes various combinations of various aspects each having different features, those skilled in the art will understand that any feature of one aspect may be combined with features of other aspects in any manner not publicly denied or that is not functionally or logically inconsistent with the operation or function of the device of the disclosed aspects of the present invention.

[0071] It is understood that the use of personally identifiable information should be subject to privacy policies and practices that are generally recognized to meet or exceed industry or government requirements for maintaining user privacy. Specifically, personally identifiable information data should be managed and processed to minimize the risk of unintentional or unauthorized access or use, and the nature of authorized use should be clearly stated to users.

[0072] It will be apparent to those skilled in the art that various modifications may be made to the present disclosure without departing from the spirit or scope of the present disclosure. Therefore, the present disclosure is intended to cover modifications and variations of the present disclosure provided that these modifications and variations are within the scope of the appended claims and their equivalents.

Claims

1. A network element implementing a unified data management (UDM) function of a core network, comprising: One or more processors configured to perform operations including: Initiating a user equipment (UE) parameter update for a routing indicator update, the routing indicator update comprising updating an old routing indicator being used by the UE to a new routing indicator, wherein the old routing indicator is associated with an old unified data management (UDM) instance and an old authentication server function (AUSF) instance, and the new routing indicator is associated with a new UDM instance and a new AUSF instance; sending a transmission including a notification of the UE parameter update to an access and mobility management function (AMF) of the core network; receiving an indication from the AMF that the UE is unreachable; as well as In response to an indication from the AMF that the UE is unreachable, setting the status of the routing indicator update to pending.

2. The network component of claim 1, wherein the operations further comprise: protecting the new routing indicator, wherein protecting the new routing indicator comprises determining a UE parameter update (UPU) counter based on an AUSF key; The old UDM instance and the old AUSF instance grant the new UDM instance and the new AUSF instance access to the UE subscription information, When the AMF contacts the new UDM instance to obtain the UE subscription information or update the location of the UE, it requests to delete the UE subscription information on the old UDM instance and the old AUSF instance, or to obtain access rights to the UE subscription information from the old UDM instance and the old AUSF instance.

3. The network component of claim 2, wherein the AMF's contact with the new UDM indicates to the core network that a routing indicator change procedure has been successfully completed.

4. The network component of claim 2, wherein the operations further comprise: If the AMF contacts the old UDM instance to obtain the UE subscription information or update the location of the UE, the routing indicator change procedure is repeated.

5. The network component of claim 4, wherein the old UDM instance repeats the routing indicator change procedure using the same UPU parameter counter in the transmission.

6. The network component of claim 4, wherein the old UDM instance repeats the routing indicator change procedure using a new UPU counter.

7. An apparatus for implementing a unified data management (UDM) function of a core network, comprising: One or more processors configured to perform operations comprising: Initiating a user equipment (UE) parameter update for a routing indicator update, the routing indicator update comprising updating an old routing indicator being used by the UE to a new routing indicator, wherein the old routing indicator is associated with an old unified data management (UDM) instance and an old authentication server function (AUSF) instance, and the new routing indicator is associated with a new UDM instance and a new AUSF instance; sending a transmission including a notification of the UE parameter update to an access and mobility management function (AMF) of the core network; receiving an indication from the AMF that the UE is unreachable; and In response to an indication from the AMF that the UE is unreachable, setting the status of the routing indicator update to pending.

8. The apparatus of claim 7, wherein the operations further comprise: protecting the new routing indicator, wherein protecting the new routing indicator comprises determining a UE parameter update (UPU) counter based on an AUSF key; The old UDM instance and the old AUSF instance grant the new UDM instance and the new AUSF instance access to the UE subscription information, When the AMF contacts the new UDM instance to obtain the UE subscription information or update the location of the UE, it requests to delete the UE subscription information on the old UDM instance and the old AUSF instance, or to obtain access rights to the UE subscription information from the old UDM instance and the old AUSF instance.

9. The apparatus of claim 8, wherein the contact of the AMF with the new UDM indicates to the core network that a routing indicator change procedure has been successfully completed.

10. The apparatus of claim 8, wherein the operations further comprise: If the AMF contacts the old UDM instance to obtain the UE subscription information or update the location of the UE, the routing indicator change procedure is repeated.

11. The apparatus of claim 10, wherein the old UDM instance repeats the routing indicator change procedure using the same UPU parameter counter in the transmission.

12. The apparatus of claim 10, wherein the old UDM instance repeats the routing indicator change procedure using a new UPU counter.

13. A computer-readable storage medium comprising a set of instructions that, when executed by a processor of a unified data management (UDM) function of a core network, causes the processor to perform operations comprising: Initiating a user equipment (UE) parameter update for a routing indicator update, the routing indicator update comprising updating an old routing indicator being used by the UE to a new routing indicator, wherein the old routing indicator is associated with an old unified data management (UDM) instance and an old authentication server function (AUSF) instance, and the new routing indicator is associated with a new UDM instance and a new AUSF instance; sending a transmission including a notification of the UE parameter update to an access and mobility management function (AMF) of the core network; receiving an indication from the AMF that the UE is unreachable; as well as In response to an indication from the AMF that the UE is unreachable, setting the status of the routing indicator update to pending.

14. The computer-readable storage medium of claim 13, wherein the operations further comprise: protecting the new routing indicator, wherein protecting the new routing indicator comprises determining a UE parameter update (UPU) counter based on an AUSF key; The old UDM instance and the old AUSF instance grant the new UDM instance and the new AUSF instance access to the UE subscription information, When the AMF contacts the new UDM instance to obtain the UE subscription information or update the location of the UE, it requests to delete the UE subscription information on the old UDM instance and the old AUSF instance, or to obtain access rights to the UE subscription information from the old UDM instance and the old AUSF instance.

15. The computer-readable storage medium of claim 14, wherein the contact of the AMF with the new UDM indicates to the core network that a routing indicator change procedure has been successfully completed.

16. The computer-readable storage medium of claim 14, wherein the operations further comprise: If the AMF contacts the old UDM instance to obtain the UE subscription information or update the location of the UE, the routing indicator change procedure is repeated.

17. The computer-readable storage medium of claim 16, wherein the old UDM instance repeats the routing indicator change procedure using the same UPU parameter counter in the transmission.

18. The computer-readable storage medium of claim 16, wherein the old UDM instance repeats the routing indicator change procedure using a new UPU counter.

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