Method and apparatus for enhancing network slice selection auxiliary information storage management in mobile communications

Abstract

Various solutions are described for network slice selection assistance information (NSSAI) storage management enhancement in mobile communications. The apparatus may receive a rejected or pending NSSAI from the first network over the first access. The device may perform a registration procedure with the second network over the first access. The device may determine whether it is registered with the first network via the second access. Where the device is not registered to the first network through the second access, the device may delete the rejected or pending NSSAI.

Description

[0001] Cross-reference to related applications

[0002] This invention is a part of a non-provisional application claiming priority to U.S. Patent Application No. 63 / 587,173, filed October 2, 2023, the contents of which are incorporated herein by reference in their entirety. Technical Field

[0003] This invention relates generally to mobile communications, and more specifically to enhancements in the storage management of network slice selection assistance information (NSSAI) in mobile communications. Background Technology

[0004] Unless otherwise stated in this invention, the methods described in this section are not prior art to the claims listed below, and are included in this section but are not acknowledged as prior art.

[0005] A public land mobile network (PLMN) is a network established and operated by a regulatory authority or recognized operating agency (ROA) with the specific purpose of providing terrestrial mobile communication services to the public. A PLMN can contain multiple radio access networks (RANs), which utilize different radio access technologies (RATs) to access mobile services. The RAN is part of the mobile communication system and is used to implement the radio access technologies. Conceptually, the RAN sits between mobile devices and their core network (CN) and provides connectivity. According to the 3G Partnership Programme (GPP),... rd In the Generation Partnership Project (3GPP) standard, mobile phones and other mobile devices have different names, such as user equipment (UE), terminal equipment (TE), mobile station (MS), or mobile termination (MT). Different RATs include second generation (2G). nd 2G) Global System for Mobile Communications (GSM), 3G (3G) rdGeneration 3G (Universal Mobile Telecommunications System, UMTS), 4G (Long Term Evolution, 4G) th generation, LTE), fifth generation (5G) th 3GPP access RATs such as 5G New Radio (NR) and other non-3GPP access RATs, such as Wireless Fidelity (Wi-Fi).

[0006] Compared to a PLMN, a non-public network (NPN) is a network intended for non-public use. An NPN can be a stand-alone NPN (SNPN), operated by the NPN operator and independent of the network functions provided by the PLMN; or a public network integrated NPN (PNI-NPN), deployed with PLMN support. The Credentials Holder (CH) can authenticate and authorize the SNPN independently of the CH. A combination of the PLMN ID and the Network Identifier (NID) is used to identify the SNPN. UEs can enable SNPNs.

[0007] In 3GPP Release 18, UEs can configure special NSSAI information, such as rejected NSSAIs and / or pending NSSAIs, and can store this special NSSAI information for subsequent operations (such as network slice selection). For example, if a network slice is in a rejected / pending NSSAI state, the UE should not select that network slice to provide mobile service. However, in the current 3GPP Release 18 standard, the NSSAI storage rules for deleting rejected / pending NSSAIs when a UE enters, selects, or registers to a new PLMN / SNPN are not yet clear. Furthermore, the NSSAI storage rules for deleting rejected / pending NSSAIs lack handling for SNPNs. Therefore, UEs may incorrectly retain or delete rejected / pending NSSAIs, leading to operational errors. Consequently, mobile service may be hindered or delayed due to these erroneous operations, thus impairing the user experience.

[0008] Therefore, appropriate solutions are needed to address these issues. Summary of the Invention

[0009] The following overview is illustrative only and is not intended to be limiting in any way. That is, it is provided to introduce the concepts, highlights, benefits, and advantages of the novel and non-obvious techniques described in this invention. Selective embodiments are further described in the detailed description below. Therefore, the following overview is not intended to identify the essential features of the claimed subject matter, nor is it intended to determine the scope of the claimed subject matter.

[0010] One object of this invention is to provide solutions, concepts, designs, systems, methods, and apparatus related to enhanced NSSAI storage management in mobile communications. It is believed that by implementing one or more of the solutions described in this invention, the aforementioned problems can be avoided or mitigated.

[0011] In one aspect, a method may include: a device receiving a rejected or pending NSSAI from a first network via a first access. The method may further include: the device performing a registration process with a second network via the first access. The method may further include: the device determining whether it has registered with the first network via the second access. If the device has not registered with the first network via the second access, the method may further include: the device deleting the rejected or pending NSSAI.

[0012] In one aspect, an apparatus may include a transceiver that wirelessly communicates with a first network or a second network during operation. The apparatus may further include a processor communicatively coupled to the transceiver. During operation, the processor may perform the following operations: receive rejected or pending NSSAIs from the first network via the transceiver through a first access. The processor may also perform the following operations: perform a registration process with the second network via the transceiver through the first access. The processor may further perform the following operations: determine whether the device has registered with the first network through the second access. If the device has not registered with the first network through the second access, the processor may further perform the following operations: delete the rejected or pending NSSAIs.

[0013] It is worth noting that although the description provided in this invention may be based on certain wireless access technologies, networks, and network topologies, such as LTE, LTE-Advanced, LTE-Advanced Pro, 5G, NR, Internet of Things (IoT) and Narrowband Internet of Things (NB-IoT), Industrial Internet of Things (IIoT), Beyond 5G (B5G), and 6G, the proposed concepts, schemes, and any variations / derivatives thereof can be applied to other types of wireless access technologies, networks, and network topologies. Therefore, the scope of this invention is not limited to the examples described herein. Attached Figure Description

[0014] The accompanying drawings are included to provide a further understanding of the invention and are incorporated in and constitute a part of this invention. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. It should be noted that the drawings are not necessarily drawn to scale, as in actual implementations some components may be shown out of proportion to clearly illustrate the concepts of the invention.

[0015] Figure 1 is an example scenario diagram of a communication environment illustrating various solutions and schemes implemented according to the present invention.

[0016] Figure 2 is a scenario diagram illustrating an enhanced NSSAI storage management example according to an embodiment of the present invention.

[0017] Figure 3 is a block diagram of an example communication system according to an embodiment of the present invention.

[0018] Figure 4 is an example process diagram according to an embodiment of the present invention. Detailed Implementation

[0019] This invention discloses detailed embodiments and implementations of the claimed subject matter. However, it should be understood that the disclosed embodiments and implementations are merely illustrative of the claimed subject matter, which can be embodied in various forms. The invention can be embodied in many different forms and should not be construed as limited to the exemplary embodiments and implementations set forth herein. Rather, these exemplary embodiments and implementations are provided so that the description of the invention will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. In the following description, details of well-known features and techniques may be omitted to avoid unnecessarily obscuring the presented embodiments and implementations.

[0020] Overview

[0021] Embodiments of this invention relate to various technologies, methods, schemes, and / or solutions related to enhanced NSSAI storage management in mobile communications. According to this invention, many possible solutions can be implemented individually or in combination. That is, although these possible solutions will be described separately below, two or more of them can be implemented in some combination.

[0022] In this invention, the network sends rejected NSSAIs to inform the UE of one or more single-NSSAIs (S-NSSAIs) included in the NSSAIs requested in the Registration Request message but rejected by the network. A rejected NSSAI can include a set of rejected S-NSSAIs, each of which can contain an S-NSSAI and an associated reason value. For example, reason value 0 indicates "S-NSSAI is unavailable in the current PLMN or SNPN", reason value 1 indicates "S-NSSAI is unavailable in the current registered area", reason value 2 indicates "S-NSSAI is unavailable due to network slice-specific authentication and authorization failure or revocation", and so on. Furthermore, the network sends pending NSSAIs to inform the UE of one or more pending S-NSSAIs because the network slice-specific authentication and authorization process has not yet been completed. The NSSAI to be processed can include a set of S-NSSAIs to be processed, and each S-NSSAI to be processed can include an S-NSSAI and an optional mapping S-NSSAI.

[0023] Figure 1 illustrates an example scenario 100 of a communication environment in which various solutions and schemes of the present invention can be implemented. Scenario 100 includes a UE 110 communicating wirelessly with a wireless network 120 (e.g., a 5G system (5GS)) and / or a wireless network 130 (e.g., a 5GS or an evolved packet system (EPS)) via 3GPP access 122 / 132 and / or non-3GPP access 140. 3GPP access 122 and 3GPP access 132 may be provided by the RAN of wireless networks 120 / 130 (e.g., including at least one Next Generation Node-B (gNB) or at least one evolved Node-B (eNB)), while non-3GPP access 140 may be provided by a Wi-Fi access point (AP) connected to the Internet. Wireless networks 120 and 130 may belong to different PLMNs / SNPNs. For example, interoperability between a non-3GPP access point 140 and network 120 (e.g., 5GS) can be achieved through the Y2 interface, which connects the non-3GPP access point 140 to a core network node, such as a non-3GPP interworking function (N3IWF). Similarly, interoperability between a non-3GPP access point 140 and network 130 (e.g., EPS) can be achieved through the SWn interface, which connects the non-3GPP access point 140 to a core network node, such as an evolved packet data gateway (ePDG). For example, interoperability between network 120 (e.g., 5GS) and network 130 (e.g., EPS) can be supported through the N26 interface and / or the S5 interface. The N26 interface connects to core network nodes, such as the 4G mobility management entity (MME) and the 5G access and mobility management function (AMF), to coordinate the UE's mobility management; the S5 interface connects to core network nodes, such as the 4G serving gateway (SGW) and the 5G packet gateway (PGW), to coordinate the UE's data connectivity.Although not shown in the figure, both wireless networks 120 and 130 can be further connected to the Internet Protocol (IP) Multimedia Subsystem (IMS), which is responsible for providing IP multimedia services, including voice call services (e.g., Voice over IP (VoIP), Voice over LTE (VoLTE), and Voice over NR (VoNR)) and emergency services (e.g., circuit-switched (CS) emergency calls, emergency bearer services, etc.). In this communication environment, as described below, UE 110 can implement various schemes related to NSSAI storage management enhancements in mobile communications according to the present invention. It is worth noting that although various proposed schemes may be described individually or separately below, in actual implementation, some or all of the proposed schemes may be used in combination or otherwise implemented. Of course, each proposed scheme may also be implemented individually or separately or otherwise.

[0024] In the current 3GPP Release 18 standard, the NSSAI storage rule for deleting rejected / pending NSSAIs uses the term "current PLMN / SNPN" after the UE enters, selects, or registers with a new PLMN / SNPN. Specifically, the NSSAI storage rule stipulates that when a UE successfully registers with a new PLMN / SNPN, or enters the 5GMM-DEREGISTERED state after failing to register with a new PLMN, or performs an inter-system handover from N1 mode to S1 mode and the UE successfully completes the tracking area update process, if the UE has not registered with the current PLMN / SNPN through other access methods, the rejected NSSAI of the current PLMN / SNPN should be deleted. Furthermore, the NSSAI storage rules stipulate that when a UE successfully registers to a new PLMN or new SNPN not in the equivalent PLMN list, or enters the 5GMM-DEREGISTERED state after failing to register to a new PLMN or SNPN, or successfully initiates an attach or tracking area update procedure in S1 mode while the UE is in single registration mode, if the UE has not registered to the current PLMN / SNPN through other access methods, the pending NSSAI of the current PLMN and its equivalent PLMN or current SNPN in the registration area should be deleted. However, once a new PLMN / SNPN is selected / entered / registered, that new PLMN / SNPN becomes the current PLMN / SNPN, so using "new PLMN / SNPN" and "current PLMN / SNPN" in the same paragraph can be misleading. Additionally, the NSSAI storage rules lack processing for SNPNs in some cases. Therefore, the UE may incorrectly retain or delete rejected / pending NSSAIs, leading to operational errors. Consequently, mobile services may be hindered or delayed due to these erroneous operations, thus impairing the user experience.

[0025] In view of the above, this invention proposes a series of schemes related to enhancing NSSAI storage management in mobile communications. According to the schemes of this invention, by replacing "current PLMN / SNPN" with "PLMN / SNPN providing the rejected / pending NSSAI and its equivalent PLMN / SNPN", and adding processing for missing SNPNs, the NSSAI storage rules for deleting rejected / pending NSSAIs are enhanced. More specifically, when a UE receives a rejected / pending NSSAI from a first network (e.g., PLMN or SNPN) through an access point (e.g., 3GPP access and non-3GPP access), the rejected / pending NSSAI is stored in the non-volatile memory of the UE's mobile equipment (ME) (e.g., the ME and the universal subscriber identity module (USIM) together constitute the UE). Then, when a UE enters / selects / registers to a new network (e.g., a second network, such as a PLMN or SNPN) through the same access and fails to register to the first network (i.e., the network providing the rejected / pending NSSAI) or its equivalent network through another access (e.g., another 3GPP access and non-3GPP access), the UE can delete the rejected / pending NSSAI. Therefore, by applying the solution of this invention, rejected / pending NSSAIs can be properly managed, thereby ensuring the normal operation of mobile communications.

[0026] Figure 2An example scenario 200 of enhanced NSSAI storage management according to an implementation of the present invention is illustrated. In step 201, UE 210 receives a non-access stratum (NAS) message including rejected / pending NSSAIs from first network 220 via first access 240 (e.g., one of 3GPP access or non-3GPP access). In one example, the NAS message including rejected NSSAIs can be a registration acceptance message, a registration rejection message, a deregistration request message, or a configuration update command message. In another example, the NAS message including pending NSSAIs can be a registration acceptance message. In step 202, UE 210 stores the rejected / pending NSSAIs in the non-volatile memory of ME. In step 203, UE 210 performs a registration process with second network 230 via the first access. For example, the registration process may include a registration process in N1 mode, or a system switch from N1 mode to S1 mode, or an attachment or tracking area update process in S1 mode.

[0027] Subsequently, in step 204, UE 210 determines that a specific condition is met and UE 210 has not registered to the first network 220 via a second access (e.g., another of a 3GPP access and a non-3GPP access). For example, if a rejected NSSAI is received in step 201, the specific condition may include one of the following: (i) UE 210 successfully registers to a new PLMN / SNPN; (ii) UE 210 enters the 5GMM-DEREGISTERED state after failing to register to a new PLMN / SNPN; and (iii) UE 210 performs an inter-system handover from N1 mode to S1 mode, and UE 210 successfully completes the tracking area update process. In another example, if a pending NSSAI is received in step 201, the specific conditions may include one of the following: (i) UE 210 successfully registers to a new PLMN or a new SNPN not in the equivalent PLMN list; (ii) UE 210 enters the 5GMM-DEREGRISTERED state after failing to register to a new PLMN or a new SNPN not in the equivalent PLMN list; and (iii) UE 210 successfully initiates an attach or tracking area update procedure in S1 mode, and UE 210 operates in single registration mode. In step 205, UE 210 removes the rejected / pending NSSAI from the first network 220 (and its equivalent network (e.g., PLMN / SNPN)).

[0028] Exemplary Implementation

[0029] Figure 3 illustrates an example communication system 300 including an example communication device 310 and an example network device 320 according to an embodiment of the present invention. Both the communication device 310 and the network device 320 can perform various functions to implement the schemes, technologies, processes, and methods related to NSSAI storage management enhancement in mobile communications described in this invention, including the scenarios / schemes described above and the process 400 described below.

[0030] The communication device 310 may be part of an electronic device, which may be a UE (User Equipment), such as a portable or mobile device, wearable device, wireless communication device, or computing device. For example, the communication device 310 may be implemented in a smartphone, smartwatch, personal digital assistant, electronic control unit (ECU) in a vehicle, digital camera, or computing device (e.g., tablet, laptop). The communication device 310 may also be part of a machine-type device, which may be an IoT, NB-IoT, IIoT, BL, or CE UE, such as a fixed or non-mobile device, home appliance, roadside unit (RSU), wired communication device, or computing device. For example, the communication device 310 may be applied to a smart thermostat, smart refrigerator, smart door lock, wireless speaker, or home control center. Alternatively, the communication device 310 may be implemented as one or more integrated circuit (IC) chips, such as, but not limited to, one or more single-core processors, one or more multi-core processors, one or more reduced-instruction-set computing (RISC) processors, or one or more complex-instruction-set computing (CISC) processors. The communication device 310 may include at least some of the components shown in FIG3, such as processor 312. The communication device 310 may also include one or more other components unrelated to the proposed embodiments of the present invention (e.g., internal power supply, display device, and / or user interface device); therefore, for the sake of brevity, such components of the communication device 310 are not shown in FIG3 and will not be described below.

[0031] Network device 320 may be part of an electronic device, which may be a network node of a wireless network (e.g., a 4G / 5G / B5G / 6G network), such as a non-3GPP access node (e.g., a Wi-Fi AP) or a 3GPP access node (e.g., an eNB, gNB, TRP, small cell, router, or gateway), and connects communication device 310 to the core network of the wireless network (e.g., an EPC or 5GC). For example, network device 320 may be implemented as one or more integrated circuit chips, such as, but not limited to, one or more single-core processors, one or more multi-core processors, or one or more RISC or CISC processors. Network device 320 may include... Figure 3At least some components are shown, such as processor 322. Network device 320 may also include one or more other components unrelated to the present invention (e.g., internal power supply, display device, and / or user interface device); therefore, for brevity, these components of network device 320 are... Figure 3 It is not shown in the text and will not be described in the following text.

[0032] On the one hand, both processor 312 and processor 322 can be implemented as one or more single-core processors, one or more multi-core processors, or one or more CISC processors. That is, although the present invention uses the singular term "processor" to refer to processor 312 and processor 322, according to the present invention, in some implementations, processor 312 and processor 322 can both contain multiple processors, while in other implementations, each processor can contain a single processor. On the other hand, both processor 312 and processor 322 can be implemented in hardware (and optional firmware), whose electronic components include, but are not limited to, one or more transistors, one or more diodes, one or more capacitors, one or more resistors, one or more inductors, one or more memristors, and / or one or more varactor diodes, which are configured and arranged according to the present invention to achieve a specific purpose. In other words, at least in some embodiments, processor 312 and processor 322 are both dedicated machines designed, arranged, and configured specifically for performing specific tasks, including enhancing NSSAI storage management in mobile communications in user equipment (e.g., represented by communication device 310) according to various embodiments of the present invention.

[0033] In some embodiments, the communication device 310 may further include a transceiver 316 coupled to the processor 312, which is capable of wirelessly transmitting and receiving data. In some embodiments, the transceiver 316 may wirelessly communicate with different types of UEs and / or different RATs' wireless networks, such as 2G GSM, 3G UMTS, 4G LTE, 5G NR, and / or 6G. In some embodiments, the transceiver 316 may be equipped with multiple antenna ports (not shown), for example, four antenna ports. That is, the transceiver 316 may be equipped with multiple transmit antennas and multiple receive antennas for multiple-input multiple-output (MIMO) wireless communication. In some embodiments, the network device 320 may further include a transceiver 326 coupled to the processor 322. The transceiver 326 may include a transceiver capable of wirelessly transmitting and receiving data. In some embodiments, the transceiver 326 may wirelessly communicate with different types of UEs on different RATs. In some embodiments, the transceiver 326 may be equipped with multiple antenna ports (not shown), for example, four antenna ports. In other words, transceiver 326 can be equipped with multiple transmit antennas and multiple receive antennas for MIMO wireless communication.

[0034] In some embodiments, the communication device 310 may further include a memory 314 coupled to the processor 312, which can be accessed by the processor 312 and stores data therein (e.g., rejected / pending NSSAI). In some embodiments, the network device 320 may further include a memory 324 coupled to the processor 322, which can be accessed by the processor 322 and stores data therein. Both memory 314 and memory 324 may include a random-access memory (RAM), such as dynamic random-access memory (DRAM), static random-access memory (SRAM), thyristor random-access memory (T-RAM), and / or zero-capacitor random-access memory (Z-RAM). Alternatively, both memory 314 and memory 324 may include a read-only memory (ROM), such as a mask ROM (mROM), a programmable ROM (PROM), an erasable programmable ROM (EPROM), and / or an electrically erasable programmable ROM (EEPROM). Alternatively, both memory 314 and memory 324 may include a non-volatile random-access memory (NVRAM), such as flash memory, solid-state memory, ferroelectric RAM (FeRAM), magnetoresistive RAM (MRAM), and / or phase-change memory.

[0035] Both communication device 310 and network device 320 can function as communication entities and can communicate with each other using various proposed schemes according to the present invention. For ease of explanation and without limitation, the function of communication device 310 as a UE will be described below in conjunction with process 400.

[0036] Exemplary process

[0037] Figure 4 illustrates an example process 400 according to an embodiment of the present invention. Process 400 may be an example implementation of the above-described scenario / scheme, whether partially or fully implemented, involving enhancements to NSSAI storage management in mobile communications. Process 400 may represent one aspect of the functional implementation of communication device 310. Process 400 may include one or more operations, actions, or functions, as shown by one or more modules 410 to 440 in the figure. Although the individual modules of process 400 are shown as discrete modules, these modules may be split into more modules, merged into fewer modules, or removed, depending on the desired implementation. Furthermore, the individual modules of process 400 may be executed in the order shown in Figure 4, or in a different order. Process 400 may be implemented by communication device 310 or any suitable UE or machine type device. For ease of illustration and without limitation, process 400 will be described below using communication device 310 as an example of UE. Process 400 may begin with block 410.

[0038] In block 410, process 400 may include the processor 312 of communication device 310 receiving rejected or pending NSSAIs from the first network via transceiver 316 through the first access. Process 400 may proceed from block 410 to block 420.

[0039] In block 420, process 400 may include processor 312 executing a registration process to the second network via transceiver 316 through the first access. Process 400 may proceed from block 420 to block 430.

[0040] In block 430, process 400 may include processor 312 determining whether communication device 310 is registered to the first network via a second access. Process 400 may proceed from 430 to 440.

[0041] In block 440, if communication device 310 fails to register with the first network via a second access, process 400 may include processor 312 deleting the rejected or pending NSSAI.

[0042] In some embodiments, when the communication device 310 registers to the first network via a second access, process 400 may further include processor 312 determining not to delete the rejected or pending NSSAI.

[0043] In some embodiments, process 400 may further include processor 312 determining whether communication device 310 has registered to an equivalent network of the first network via the second access, and deleting rejected or pending NSSAI if communication device 310 has not registered to the equivalent network via the second access.

[0044] In some embodiments, if a rejected NSSAI is received, the communication device 310 will successfully register to the second network after the registration process is completed.

[0045] In some embodiments, upon receiving a rejected NSSAI, after the registration process fails, process 400 may further include processor 312 entering a deregistration state (e.g., 5GMM-DEREGISTERED state).

[0046] In some embodiments, upon receiving a rejected NSSAI, the registration process may include a system-to-system switch from an advanced system to a legacy system (i.e., from N1 mode to S1 mode), and the communication device 310 successfully completes the tracking area update process.

[0047] In some embodiments, upon receiving an pending NSSAI, the communication device 310 successfully registers to a second network not in the equivalent network list after the registration process is completed.

[0048] In some implementations, upon receiving an pending NSSAI, after the registration process with a second network not in the equivalent network list fails, process 400 may also include processor 312 entering a deregistration state (e.g., 5GMM-DEREGISTERED state).

[0049] In some embodiments, upon receiving an pending NSSAI, the registration process may include an attachment or tracking area update process and the communication device 310 operates in single registration mode.

[0050] In some embodiments, both the first network and the second network may include a PLMN or an SNPN.

[0051] In some embodiments, the first access may include one of 3GPP access and non-3GPP access, and the second access may include one of 3GPP access and non-3GPP access.

[0052] Supplementary Explanation

[0053] The subject matter described in this invention sometimes illustrates different components contained within or connected to other components. It should be understood that the depicted architecture is merely an example, and many other architectures that achieve the same functionality can actually be implemented. Conceptually, any arrangement of components achieving the same function is effectively “associated” to achieve the desired function. Therefore, regardless of the architecture or intermediate components, any two components of this invention combined to achieve a specific function can be considered “associated” with each other to achieve the desired function. Similarly, any two such associated components can also be considered “operationally connected” or “operationally coupled” to achieve the desired function, and any two components that can be suchly associated can also be considered “operationally coupled” to achieve the desired function. Specific examples of operationally coupled components include, but are not limited to: physically mating and / or physically interacting components and / or wirelessly interacting components and / or logically interacting and / or logically interactable components.

[0054] Furthermore, regarding the extensive use of any plural and / or singular terms in this invention, those skilled in the art can, depending on the context and / or application, convert from plural to singular and / or from singular to plural. For clarity, various singular / plural interchanges can be explicitly described in this invention.

[0055] Furthermore, those skilled in the art will understand that, generally, the terminology used in this invention, and especially in the appended claims (e.g., the text of the appended claims), generally means "open" terms (e.g., the term "comprising" should be interpreted as "including but not limited to," the term "having" should be interpreted as "having at least," the term "including" should be interpreted as "including but not limited to," etc.). Those skilled in the art will also understand that if a particular number of claims is intentionally enumerated, this intention will be explicitly listed in the claims, and if such enumeration is absent, this intention will not exist. For example, to aid understanding, the appended claims may include the use of the introductory phrases "at least one" and "one or more" that enumerate the claims. However, the use of such phrases should not be interpreted as implying that the introduction of the indefinite article "a" or "an" by a claim list limits any particular claim containing such an introduced claim list to an embodiment containing only one such list, even when the same claim includes the introductory phrase "one or more" or "at least one" and an indefinite article (such as "a" or "an"). (For example, "a" and / or "an" should be interpreted as meaning "at least one" or "one or more"); the same applies to the use of definite articles used to introduce claim lists. Furthermore, even when a specific number of introduced claim lists is explicitly listed, those skilled in the art will recognize that such a list should be interpreted as meaning at least the number listed (e.g., in the absence of other modifiers, an unmodified list of "two lists" means at least two lists, or two or more lists). Furthermore, in cases where the convention of "at least one of A, B, and C" is used, this interpretation generally means, as those skilled in the art will understand, that "a system having at least one of A, B, and C" includes, but is not limited to, systems having A alone, having B alone, having C alone, having A and B together, having A and C together, having B and C together, and / or having A, B, and C together. In cases where the convention of "at least one of A, B, or C" is used, this interpretation generally means, as those skilled in the art will understand, that "a system having at least one of A, B, or C" includes, but is not limited to, systems having A alone, having B alone, having C alone, having A and B together, having A and C together, having B and C together, and / or having A, B, and C together. Those skilled in the art will also understand that any transitional words and / or phrases that actually present two or more alternatives, whether in the specification, claims, or drawings, should be understood to contemplate the possibility of including one, any, or both of these items. For example, the phrase “A or B” would be understood to include the possibility of “A” or “B” or “A and B”.

[0056] Based on the foregoing, it will be understood that various embodiments of the invention have been described for illustrative purposes, and various modifications can be made without departing from the scope and spirit of the invention. Therefore, the various embodiments disclosed herein are not intended to be limiting, and the true scope and spirit are indicated by the appended claims.

Claims

1. A method comprising: The device’s processor receives network slice selection assistance information (NSSAI) that is rejected or pending from the first network via the first access. The processor performs the registration process with the second network through the first access point; The processor determines whether to register to the first network via the second access method; as well as If the device fails to register with the first network via the second access, the processor deletes the rejected or pending NSSAI.

2. The method of claim 1, further comprising: If the device registers with the first network via the second access, the processor determines not to delete the rejected or pending NSSAI.

3. The method of claim 1, further comprising: The processor determines whether the device has registered to the equivalent network of the first network through the second access; as well as If the device fails to register with the equivalent network via the second access, the processor deletes the rejected or pending NSSAI.

4. The method of claim 1, wherein, Upon receiving the rejected NSSAI, the device successfully registered to the second network after the registration process.

5. The method of claim 1, further comprising: Upon receiving the rejected NSSAI, the processor enters a deregistration state after the registration process fails.

6. The method of claim 1, wherein, Upon receiving the rejected NSSAI, the registration process includes a system switch from an advanced system to a legacy system, and the device successfully completes the tracking area update process.

7. The method of claim 1, wherein, Upon receiving the pending NSSAI, the device successfully registers to the second network, which is not in the equivalent network list, after the registration process.

8. The method of claim 1, further comprising: Upon receiving the pending NSSAI, the processor enters a deregistration state after the registration process with the second network, which is not in the equivalent network list, fails.

9. The method of claim 1, wherein, Upon receiving the pending NSSAI, the registration process includes an attachment or tracking area update process, and the device operates in single registration mode.

10. The method of claim 1, wherein, Both the first network and the second network include a Public Land Mobile Network (PLMN) or a Standalone Non-Public Network (SNPN). The first access includes one of 3GPP access and non-3GPP access, and the second access includes one of 3GPP access and non-3GPP access.

11. An apparatus comprising: A transceiver that communicates wirelessly with a first or second network during operation; as well as A processor, communicatively coupled to a transceiver, enables the processor to perform the following operations during operation: The transceiver receives rejected or pending network slice selection assistance information (NSSAI) from the first network via the first access. The registration process is performed with the second network via the transceiver and the first access point; Determine whether the device has registered with the first network through the second access; as well as If the device fails to register with the first network via the second access, the rejected or pending NSSAI is deleted.

12. The apparatus of claim 11, wherein, During operation, the processor also performs the following operations: If the device registers with the first network via the second access, it is determined not to delete the rejected or pending NSSAI.

13. The apparatus of claim 11, wherein, During operation, the processor also performs the following operations: Determine whether the device has registered to the equivalent network of the first network via the second access method; and If the device has not registered to the equivalent network via the second access method, delete the rejected or pending NSSAI.

14. The apparatus of claim 11, wherein, Upon receiving the rejected NSSAI, the device successfully registers to the second network after the registration process.

15. The apparatus of claim 11, wherein, During operation, the processor also performs the following operations: Upon receiving the rejected NSSAI, the registration process fails and the user enters a deregistration state.

16. The apparatus of claim 11, wherein, Upon receiving the rejected NSSAI, the registration process includes a system switch from an advanced system to a legacy system, and the device successfully completes the tracking area update process.

17. The apparatus of claim 11, wherein, Upon receiving the pending NSSAI, the device successfully registers to the second network, which is not in the equivalent network list, after the registration process.

18. The apparatus of claim 11, wherein, During operation, the processor also performs the following operations: Upon receiving the pending NSSAI, the system enters a deregistration state after the registration process with the second network, which is not in the equivalent network list, fails.

19. The apparatus of claim 11, wherein, Upon receiving the pending NSSAI, the registration process includes an append or tracking region update process, and the device operates in single registration mode.

20. The apparatus of claim 11, wherein, Both the first network and the second network include a Public Land Mobile Network (PLMN) or a Standalone Non-Public Network (SNPN). The first access includes one of 3GPP access and non-3GPP access, and the second access includes one of 3GPP access and non-3GPP access.

Images