Method and UE for performing RID update in UE in wireless communication network

Abstract

The present disclosure relates to a communication method and system for converging a 5th generation (5G) communication system and an Internet of Things (IoT) technology, wherein the 5G communication system is used to support a higher data rate than a 4th generation (4G) system. The present disclosure can be applied to smart services based on 5G communication technology and IoT-related technologies, such as smart homes, smart buildings, smart cities, smart cars, connected cars, healthcare, digital education, smart retail, safety and security services. Embodiments herein provide a method for performing a routing ID (RID) update in a user equipment (UE) in a wireless communication network.

Description

Technical Field

[0001] Embodiments herein relate to wireless communications, and more particularly, to a method and UE (100) for performing a routing ID (RID) update in a user equipment (UE) in a wireless communication network. Background Art

[0002] Since the deployment of 4G communication systems, efforts have been made to develop improved 5G or quasi-5G communication systems in order to meet the demand for increased wireless data services. 5G or quasi-5G communication systems are also referred to as "super 4G networks" or "post-LTE (Long Term Evolution) systems". 5G communication systems are considered to be implemented in higher frequency (millimeter wave) bands (e.g., 60GHz bands) to achieve higher data rates. In order to reduce the propagation loss of radio waves and increase the transmission distance, beamforming, massive multiple-input multiple-output (MIMO), full-dimensional MIMO (FD-MIMO), array antennas, analog beamforming, and large antenna technology are discussed in 5G communication systems. In addition, in 5G communication systems, development of system network improvements is underway based on advanced small cells, cloud radio access networks (RANs), ultra-dense networks, device-to-device (D2D) communications, wireless backhaul, mobile networks, collaborative communications, coordinated multipoints (CoMP), receiving-end interference elimination, and the like. In 5G systems, hybrid frequency shift keying (FSK) and frequency quadrature amplitude modulation (FQAM) and sliding window superposition coding (SWSC) have been developed as advanced coded modulation (ACM), as well as filter bank multi-carrier (FBMC), non-orthogonal multiple access (NOMA) and sparse code multiple access (SCMA) as advanced access technologies.

[0003] The Internet is now evolving towards the Internet of Things (IoT), in which distributed entities (such as objects) exchange and process information without human intervention. The Internet of Everything (IoE) has emerged, which is a combination of IoT technology and big data processing technology through connection with cloud servers. With the demand for IoT implementation of technical elements such as "sensing technology", "wired / wireless communication and network infrastructure", "service interface technology" and "security technology", sensor networks, machine-to-machine (M2M) communication, machine type communication (MTC), etc. have been studied. Such IoT environments can provide smart Internet technology services that create new value for human life by collecting and analyzing data generated among networked objects. IoT can be applied to a variety of fields, including smart homes, smart buildings, smart cities, smart cars or connected cars, smart grids, health care, smart appliances and advanced medical services through the integration and combination between existing information technology (IT) and various industrial applications.

[0004] In line with this, various attempts have been made to apply 5G communication systems to IoT networks. For example, technologies such as sensor networks, MTC, and M2M communications can be implemented through beamforming, MIMO, and array antennas. The application of cloud RAN as the above-mentioned big data processing technology can also be regarded as an example of the fusion between 5G technology and IoT technology. Summary of the invention

[0005] Technical issues

[0006] A main object of the embodiments herein is to provide a method for performing a Routing ID (RID) update in a UE (100) in a wireless communication network.

[0007] Another object of embodiments herein is to receive a downlink non-access stratum (DL NAS) transport message including a second RID from a first unified data management (UDM).

[0008] Another object of the embodiments of the present invention is to perform a routing ID (RID) update in a UE (100) by waiting to enter an idle mode (IDLE mode) on a 3GPP access and triggering a deregistration process on the 3GPP access, and then triggering a registration process on the 3GPP access using a second RID.

[0009] Another object of the embodiments herein is to determine that critical services are active on non-3GPP access and to perform a routing ID (RID) update in the UE (100) by waiting for completion of critical services on the non-3GPP access, locally releasing the N1 NAS signaling connection, and entering 5G MM-IDLE mode on the non-3GPP access, performing a deregistration procedure, and then initiating a registration procedure to perform an initial registration with a newly allocated SUCI.

[0010] Another object of the embodiments herein is to provide a method for handling a UE-initiated UL NAS transmission message failure in a wireless communication network.

[0011] Another object of embodiments herein is to provide a method for managing access during updating of a routing ID by a user equipment (UE) in a wireless communication network.

[0012] Another object of embodiments herein is to receive a downlink non-access stratum (DL NAS) transport message including a RID on a 3GPP access from a first unified data management (UDM).

[0013] Another object of embodiments herein is to register a UE on both 3GPP access and non-3GPP access.

[0014] Another object of embodiments herein is to wait for activation of idle mode on 3GPP access.

[0015] Another object of embodiments herein is to deregister from a first UDM on a 3GPP access and register with a second UDM on a 3GPP access.

[0016] Solution to the problem

[0017] Therefore, embodiments of the present invention provide a method for performing a routing ID (RID) update in a user equipment (UE) (100) in a wireless communication network. The method includes receiving, by the UE (100) from a first unified data management (UDM) (300a), a second routing ID (RID) and an indication of initiating a registration process using the second RID, wherein the UE (100) is currently configured using the first routing ID (RID), and the UE (100) determines that the UE (100) is registered on a third generation partnership project (3GPP) access. In addition, the method includes performing a routing ID (RID) update in the UE (100) by the UE (100) in the following manner: waiting to enter an idle mode on the 3GPP access; triggering a deregistration process for the 3GPP access; and triggering a registration process on the 3GPP access using the second RID.

[0018] In one embodiment, the second routing ID (RID) is received in a downlink non-access stratum (DLNAS) transmission message from the wireless communication network.

[0019] Therefore, embodiments of the present invention provide a method for performing a routing ID (RID) update in a user equipment (UE) (100) in a wireless communication network. The method includes receiving, by the UE (100) from a first unified data management (UDM) (300a), a second routing ID (RID) and an indication of initiating a registration procedure using the second RID, wherein the UE (100) is currently configured using the first routing ID (RID), and determining by the UE (100) that the UE (100) is registered on a non-third generation partnership project (N3GPP) access. In addition, the method includes determining, by the UE (100), whether a critical service is active on a non-3GPP access, and in response to determining that the critical service is active on the non-3GPP access, performing, by the UE (100), a routing ID (RID) update in the UE (100) by one of the following: waiting for completion of the critical service on the non-3GPP access, locally releasing a non-access stratum (NAS) signaling connection on the non-3GPP access, and entering an idle mode, performing a deregistration procedure, and triggering a registration procedure on the non-3GPP access using a second RID. In addition, in response to determining that the critical service is not active on the non-3GPP access, immediately releasing the NAS signaling connection on the non-3GPP access and entering an idle mode, performing a deregistration procedure, and triggering a registration procedure on the non-3GPP access using a second RID.

[0020] Therefore, embodiments of the present invention provide a user equipment (UE) (100) for managing access during a routing ID (RID) update in a wireless communication network. The UE (100) includes a memory (140) and a processor (160) coupled to the memory (140). The processor (160) is configured to receive a second routing ID (RID) and an indication of initiating a registration process using the second RID from a first unified data management (UDM) (300a), wherein the UE (100) is currently configured using the first routing ID (RID), and it is determined that the UE (100) is registered on a third generation partnership project (3GPP) access. In addition, the processor (160) is further configured to perform a routing ID (RID) update in the UE (100) by: waiting to enter an idle mode on a 3GPP access; triggering a deregistration process for the 3GPP access; and triggering a registration process on the 3GPP access using the second RID.

[0021] Therefore, embodiments of the present invention provide a user equipment (UE) (100) for managing access during a routing ID (RID) update in a wireless communication network. The UE (100) includes a memory (140) and a processor (160) coupled to the memory (140). The processor (160) is configured to receive a second routing ID (RID) and an indication of initiating a registration process using the second RID from a first unified data management (UDM) (300a), wherein the UE (100) is currently configured using the first routing ID (RID). In addition, the processor (160) is further configured to determine that the UE (100) is registered on a non-3rd Generation Partnership Project (N3GPP) access and determine whether a critical service is active on the non-3GPP access. In addition, the processor (160) is also configured to perform a routing ID (RID) update in the UE (100) in response to determining that the critical service is active on the non-3GPP access by one of the following ways: waiting for the critical service on the non-3GPP access to be completed, locally releasing a non-access stratum (NAS) signaling connection on the non-3GPP access, and entering an idle mode, performing a deregistration procedure, and triggering a registration procedure using a second RID on the non-3GPP access, and in response to determining that the critical service is not active on the non-3GPP access, immediately releasing the NAS signaling connection on the non-3GPP access and entering an idle mode, performing a deregistration procedure, and triggering a registration procedure using a second RID on the non-3GPP access.

[0022] Therefore, embodiments of the present invention provide a method for handling a failure of an uplink non-access stratum (UL NAS) transmission message initiated by a UE (100) in a wireless communication network. The method includes determining, by the UE (100), a failure in transmitting a UL NAS transmission message, and determining, by the UE (100), whether the failure in transmitting the UL NAS transmission message is accompanied by a TAI change from a lower layer. In addition, the method includes performing, by the UE (100), one of the following: determining, by the UE (100), in response to determining that the failure in transmitting the UL NAS transmission message is accompanied by a TAI change from a lower layer, a method for re-executing an ongoing process for triggering a UL NAS transmission process, and determining, by the UE (100), in response to determining that the failure in transmitting the UL NAS transmission message is not accompanied by a TAI change from a lower layer, a method for handling a failure of an uplink non-access stratum (UL NAS) transmission message initiated by the UE (100).

[0023] Therefore, embodiments of the present invention provide a UE (100) for processing an uplink non-access stratum (UL NAS) transmission message failure initiated by a user equipment (UE) (100) in a wireless communication network. The UE (100) includes a memory (140) and a processor (160) coupled to the memory (140). The processor (160) is configured to determine a transmission failure of a UL NAS transmission message, and determine whether the transmission failure of the UL NAS transmission message is accompanied by a TAI change from a lower layer. In addition, the processor (160) is configured to perform one of the following: in response to determining that the transmission failure of the UL NAS transmission message is accompanied by a TAI change from a lower layer, determine a method for re-executing an ongoing process for triggering a UL NAS transmission process, and in response to determining that the transmission failure of the UL NAS transmission message is not accompanied by a TAI change from a lower layer, determine a method for processing an uplink non-access stratum (UL NAS) transmission message failure initiated by the UE (100).

[0024] These and other aspects of the embodiments herein will be better appreciated and understood when considered in conjunction with the following description and accompanying drawings. However, it should be understood that the following description is given as an illustration rather than a limitation, although preferred embodiments and many specific details thereof are indicated. Many changes and modifications may be made within the scope of the embodiments herein without departing from the spirit of the embodiments herein, and the embodiments herein include all such changes.

[0025] Advantageous Effects of the Invention

[0026] The present disclosure provides a method for performing a routing ID (RID) update in a UE (100) in a wireless communication network.

[0027] The present disclosure also provides a method for receiving a downlink non-access stratum (DL NAS) transmission message including a second RID from a first unified data management (UDM).

[0028] The present disclosure also provides a method for performing a routing ID (RID) update in a UE (100) by waiting to enter an idle mode on a 3GPP access and triggering a deregistration procedure on the 3GPP access, and then triggering a registration procedure on the 3GPP access using a second RID.

[0029] The present disclosure also provides a method for determining that a critical service is active on a non-3GPP access and performing a routing ID (RID) update in a UE (100) by waiting for completion of the critical service on the non-3GPP access, locally releasing the N1 NAS signaling connection, and entering a 5G MM-IDLE mode on the non-3GPP access, performing a deregistration procedure, and then initiating a registration procedure to perform an initial registration using a newly allocated SUCI.

[0030] The present disclosure also provides a method for processing a UL NAS transmission message failure initiated by a UE in a wireless communication network.

[0031] Other aspects, advantages, and salient features of the disclosure will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses various embodiments of the disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] For a more complete understanding of the present disclosure and its advantages, reference is now made to the following description taken in conjunction with the accompanying drawings, in which like reference numerals represent like parts:

[0033] Figure 1 A block diagram of a User Equipment (UE) (100) for performing a Routing ID (RID) update in a UE in a wireless communication network according to an embodiment as disclosed herein is shown;

[0034] Figure 2A A flow chart (200a) showing a method for performing RID update on 3GPP access in a UE (100) in a wireless communication network according to an embodiment as disclosed herein;

[0035] Figure 2B A flow chart (200b) showing a method for performing RID update on N3GPP access in a UE (100) in a wireless communication network according to an embodiment as disclosed herein;

[0036] Figure 2CA flow chart (200c) is shown of a method for handling a UE initiated uplink non-access stratum (UL NAS) transmission message failure in a wireless communication network according to an embodiment as disclosed herein;

[0037] Figure 3A A situation in which a UE (100) in a wireless communication network performs a routing ID update to switch from a first UDM (300a) to a second UDM (300b) according to the prior art is shown;

[0038] Figure 3B A scenario in which a UE (100) in a wireless communication network performs a routing ID update to switch from a first UDM (300a) to a second UDM (300b) according to an embodiment as disclosed herein is shown;

[0039] Figure 4A A situation is shown in which a UE (100) according to the prior art does not send an acknowledgement in a UL NAS transmission message, thereby causing a mismatch in UE configuration between the UE (100) and a wireless communication network;

[0040] Figure 4B Various scenarios are shown in which a UE (100) reruns an ongoing procedure that triggers a UE-initiated NAS transfer procedure according to an embodiment as disclosed herein;

[0041] Figure 5A A situation is shown in which a UE (100) according to the prior art does not re-initiate an aborted UL NAS transmission process after completing a registration update process in a wireless communication network;

[0042] Figure 5B A scenario is shown in which a UE (100) according to an embodiment as disclosed herein re-initiates an aborted UL NAS transmission procedure after completing a registration update procedure in a wireless communication network;

[0043] Fig. 6A A situation is shown in which a UE (100) according to the prior art does not re-initiate an aborted UL NAS transmission process due to processing of a deregistration process triggered by a wireless communication network;

[0044] Figure 6B A scenario is shown in which a UE (100) according to an embodiment as disclosed herein re-initiates an aborted UL NAS transmission procedure and then handles a deregistration procedure triggered by a wireless communication network.

[0045] Fig. 7A A situation is shown in which a UE (100) according to the prior art does not reinitiate an aborted UL NAS transmission procedure due to processing of a deregistration procedure triggered by an upper layer; and

[0046] Figure 7B A scenario is shown in which a UE (100) according to an embodiment as disclosed herein re-initiates an aborted UL NAS transmission procedure and later processes a deregistration procedure triggered by upper layers. DETAILED DESCRIPTION

[0047] Before proceeding to the following detailed description, it may be advantageous to set forth definitions of certain words and phrases used throughout this patent document. The terms "comprise" and "include" and their derivatives are meant to include, but are not limited to; the term "or" is inclusive, meaning and / or; the phrases "associated with" and "associated with" and their derivatives may mean include, included within, interconnected with, include, included within, connected to or connected with, coupled to or coupled with, communicable with, collaborate with, intertwine, juxtapose, proximate to, bound to or bound with, have, have a property of, and the like; and the term "controller" means any device, system, or portion thereof that controls at least one operation, such device may be implemented in hardware, firmware, or software, or some combination of at least two of hardware, firmware, or software. It should be noted that the functionality associated with any particular controller may be centralized or distributed, whether local or remote.

[0048] In addition, the various functions described below can be implemented or supported by one or more computer programs, each of which is formed by a computer-readable program code and embodied in a computer-readable medium. The terms "application" and "program" refer to one or more computer programs, software components, instruction sets, processes, functions, objects, classes, instances, related data or a part thereof suitable for being implemented with a suitable computer-readable program code. The phrase "computer-readable program code" includes any type of computer code, including source code, object code and executable code. The phrase "computer-readable medium" includes any type of medium that can be accessed by a computer, such as a read-only memory (ROM), a random access memory (RAM), a hard drive, a compact disk (CD), a digital video disc (DVD) or any other type of memory. "Non-transitory" computer-readable media excludes wired, wireless, optical or other communication links that transmit temporary electrical signals or other signals. Non-transitory computer-readable media include media in which data can be permanently stored and media in which data can be stored and rewritten later, such as rewritable optical disks or erasable memory devices.

[0049] Definitions for certain words and phrases are provided throughout this patent document, those of ordinary skill in the art should understand that in many, if not most instances, such definitions apply to prior, as well as future uses of such defined words and phrases.

[0050] Discussed below Figures 1 to 7B The various embodiments used to describe the principles of the present disclosure in this patent document are exemplary only and should not be interpreted in any way as limiting the scope of the present disclosure. Those skilled in the art will understand that the principles of the present disclosure can be implemented in any appropriately arranged system or device.

[0051] Generally, there are two types of non-access stratum (NAS) transmission procedures defined in the 3GPP 5G NAS specification (24.501) for transmitting message payloads and associated information between a user equipment (UE) and a wireless communication network. The two types of NAS transmission procedures include UE-initiated NAS transmission (UL NAS transmission) procedures and network-initiated NAS transmission (DL NAS transmission) procedures. The two types of NAS transmission procedures are independent procedures.

[0052] Conventional 3GPP protocols assume that the UE-initiated NAS transfer procedure is retried by upper layers (layers above NAS) in cases such as SMS. However, there are various scenarios, like UE receiving Steering of Roaming (SOR) information requesting confirmation, UE parameter updates (for parameters such as routing ID, slice information, etc.) requesting confirmation via the Unified Data Management (UDM) control plane, etc., where retry may not be attempted if the procedure fails. Failure of the UE-initiated NAS transfer procedure may result in a mismatch in the configuration between the UE and the wireless communication network, or may result in synchronization issues between the UE and the wireless communication network, resulting in abnormal behavior of the UE and the wireless communication network that needs to be resolved.

[0053] The above information is presented as background information only to assist the reader in understanding the present disclosure. Applicants have not made a determination and make no assertion as to whether any of the above information may be applicable as prior art to the present application.

[0054] An object of embodiments herein is to provide a method for performing a routing ID (RID) update in a UE (100) in a wireless communication network.

[0055] Another object of embodiments herein is to receive a downlink non-access stratum (DL NAS) transport message including a second RID from a first unified data management (UDM).

[0056] Another object of the embodiments herein is to perform a Routing ID (RID) update in a UE (100) by waiting to enter idle mode on a 3GPP access and triggering a deregistration procedure on the 3GPP access, and then triggering a registration procedure on the 3GPP access using a second RID.

[0057] Another object of the embodiments herein is to determine that critical services are active on non-3GPP access and to perform a routing ID (RID) update in the UE (100) by waiting for completion of critical services on the non-3GPP access, locally releasing the N1 NAS signaling connection, and entering 5G MM-IDLE mode on the non-3GPP access, performing a deregistration procedure, and then initiating a registration procedure to perform an initial registration with a newly allocated SUCI.

[0058] Another object of the embodiments herein is to provide a method for handling a UE-initiated UL NAS transmission message failure in a wireless communication network.

[0059] Another object of embodiments herein is to provide a method for managing access during updating of a routing ID by a user equipment (UE) in a wireless communication network.

[0060] Another object of embodiments herein is to receive a downlink non-access stratum (DL NAS) transport message including a RID on a 3GPP access from a first unified data management (UDM).

[0061] Another object of embodiments herein is to register a UE on both 3GPP access and non-3GPP access.

[0062] Another object of embodiments herein is to wait for activation of idle mode on 3GPP access.

[0063] Another object of embodiments herein is to deregister from a first UDM on a 3GPP access and register with a second UDM on a 3GPP access.

[0064] Various embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. In the following description, only specific details such as detailed configuration and components are provided to help fully understand these embodiments of the present disclosure. Therefore, it should be apparent to those skilled in the art that various changes and modifications may be made to the embodiments described herein without departing from the scope and spirit of the present disclosure. In addition, descriptions of well-known functions and configurations have been omitted for clarity and brevity.

[0065] Furthermore, the various embodiments described herein are not necessarily mutually exclusive, as some embodiments can be combined with one or more other embodiments to form new embodiments.

[0066] Herein, unless otherwise specified, the term "or" as used herein refers to a non-exclusive or. The examples used herein are merely to facilitate understanding of the manner in which the embodiments of the present invention may be practiced, and further enable those skilled in the art to practice the embodiments of the present invention. Therefore, these examples should not be construed as limiting the scope of the embodiments of the present invention.

[0067] As conventional in the art, each embodiment can be described and illustrated according to the block that performs one or more functions described.These blocks (which may be referred to as units, engines, managers, modules, etc. in this article) are physically implemented by analog and / or digital circuits, such as logic gates, integrated circuits, microprocessors, microcontrollers, memory circuits, passive electronic components, active electronic components, optical components, hard-wired circuits, etc., and can be optionally driven by firmware and / or software.For example, the circuit can be specifically implemented in one or more semiconductor chips, or specifically implemented on substrate supports such as printed circuit boards.The circuit constituting the block can be implemented by dedicated hardware, or by a processor (for example, one or more programmed microprocessors and associated circuits), or by a combination of dedicated hardware for executing some functions of the block and the processor and a processor for executing other functions of the block.Without departing from the scope of the present disclosure, each block of the embodiment can be physically divided into two or more interactive and discrete blocks.Similarly, without departing from the scope of the present disclosure, the blocks of the embodiment can be physically combined into more complex blocks.

[0068] The proposed method is applicable to both accesses, ie, a RID change on a 3GPP access, then the N3GPP access must be updated, or a RID change on a N3GPP access, then the 3GPP access must be updated.

[0069] The proposed method is applicable even in the INACTIVE state, ie whenever the IDLE state is specified, the INACTIVE state can be used instead.

[0070] Therefore, embodiments of the present invention provide a method for performing a routing ID (RID) update in a user equipment (UE) (100) in a wireless communication network. The method includes receiving, by the UE (100) from a first unified data management (UDM) (300a), a second routing ID (RID) and an indication of initiating a registration process using the second RID, wherein the UE (100) is currently configured using the first routing ID (RID), and the UE (100) determines that the UE (100) is registered on a third generation partnership project (3GPP) access. In addition, the method includes performing a routing ID (RID) update in the UE (100) by: waiting to enter an idle mode on the 3GPP access, i.e., the UE (100) will only move to the idle mode after receiving an RRC connection release from the wireless communication network; triggering a deregistration process for the 3GPP access; and triggering a registration process on the 3GPP access using the second RID. In addition, in order to use the second RID, a new subscription concealment identifier (SUCI) must be used, which means that the UE (100) will delete the 5G-GUTI and initiate a registration process for initial registration. The term waiting to enter idle mode on 3GPP access means that the UE (100) waits for the wireless communication network to indicate a message to the UE (100) to enter idle mode. To handle possible abnormal situations, the UE (100) can wait for the wireless communication network to indicate to the UE (100) to move to idle mode until a predetermined time (a timer may be used), after which the UE (100) can locally move to idle mode.

[0071] Typically, when a UL NAS TRANSPORT message transmission failure occurs, the upper layer is responsible for retransmitting the message so that the UL NAS transport message (i.e., process) can be retried. For example, the session management layer can send a session management message, which will be encapsulated in the UL NAS transport message at the 5GMM layer and attempted to be transmitted. If the UL NAS transport message is not successfully transmitted, the session management layer expects to retransmit the message. Therefore, it can be guaranteed that the information that needs to be communicated to the network will not be lost. However, some information is sent from the network to the UE in a NAS message (like a DL NAS transmission), which carries information that the protocol layer needs to consume, and the upper layer does not expect to retry, such as roaming control (SOR) information, UE parameter update data, etc. For such information, the NAS layer should be responsible for attempting to retry appropriately. Another important issue is that while the UE is attempting to send the UL NAS transfer message, the UE may end up initiating some other procedure, for example, while the UL NAS transfer message is being transmitted, the TAI may change, and this may cause the UE to initiate a registration procedure, the state machine in the UE will not remember that some other procedure is ongoing, and therefore the UE will lose this information, i.e., information that is expected to be sent to the network via the UL NAS transfer message will be lost, and may cause failure of those corresponding procedures. To handle this issue, the UE may determine a method for handling a UE-initiated uplink non-access stratum (UL NAS) transfer message failure when it is determined that the transmission failure of the UL NAS transfer message is accompanied by a TAI change from the lower layer. In order to determine a method for handling a failure of a UL NAS transmission message initiated by a UE, the UE determines whether a current TAI is in a TAI list transmitted by a wireless communication network, and performs one of the following: in response to determining that the current TAI is not in the TAI list transmitted by the wireless communication network, aborting transmission of a UL NAS transmission message by the UE (100), remembering (i.e., recognizing) a transmission failure that occurred for the UL NAS transmission message, and initiating a procedure for mobility and periodic registration update, and in response to determining that the current TAI is not in the TAI list transmitted by the wireless communication network, recognizing that the UL NAS transmission message was not successfully transmitted, initiating a registration procedure, retrying to transmit the UL NAS transmission message based on the recognition that the UL NAS transmission message was not successfully transmitted after completing the registration procedure. In addition, the UE can determine a method for re-performing an ongoing UL NAS transmission procedure that triggers the UL NAS transmission procedure when determining that the transmission failure of the UL NAS transmission message is not accompanied by a TAI change from a lower layer.

[0072] Referring now to the drawings and more particularly to Figures 1 to 7B , wherein like reference numerals refer to corresponding features throughout, a preferred embodiment and the prior art are shown for comparison with the preferred embodiment.

[0073] Figure 1 A block diagram of a User Equipment (UE) (100) for performing a Routing ID (RID) update in a UE in a wireless communication network is shown according to embodiments as disclosed herein.

[0074] See also Figure 1 UE (100) may be, for example, a mobile phone, a smart phone, a personal digital assistant (PDA), a tablet computer, a wearable device, etc. In one embodiment, UE (100) may include a communicator (120), a memory (140), and a processor (160).

[0075] In one embodiment, the communicator (120) is configured to receive a downlink non-access stratum (DL NAS) transmission message. The DL NAS includes a second routing ID on a third generation partnership project (3GPP) access from a first UDM (300a). The UE (100) is currently configured using a first routing ID (RID). The second routing ID indicates that the UE (100) initiates a registration with the second UDM (300b). The term routing ID (RID) can be used interchangeably with a routing indicator, which is defined as an identifier assigned by the UE's home network operator, which identifier will be used together with the home network identifier for routing network signaling. The routing indicator is provided in a universal subscriber identity module (USIM) of the UE (100).

[0076] In another embodiment, the communicator (120) is configured to receive a deregistration request message from one of: at least one upper layer above the NAS layer and a wireless communication network. In addition, the communicator (120) is further configured to receive a L2 ACK for successfully transmitting a UL NAS transmission message during a UL NAS transmission process.

[0077] In one embodiment, the memory (140) may include a non-volatile storage element. Examples of such non-volatile storage elements may include a magnetic hard disk, an optical disk, a floppy disk, a flash memory, or various forms of electrically programmable memory (EPROM) or electrically erasable programmable memory (EEPROM). In addition, in some examples, the memory (140) may be considered a non-transitory storage medium. The term "non-transitory" may indicate that the storage medium is not specifically implemented in a carrier or propagating signal. However, the term "non-transitory" should not be interpreted as the memory (140) being non-removable. In some examples, the memory (140) may be configured to store more information than the memory. In some examples, the non-transitory storage medium may store data that may change over time (e.g., in a random access memory (RAM) or a cache).

[0078] In one embodiment, the processor (160) includes a registration management engine (162), a critical services management engine (164), and a non-access stratum (NAS) transport management engine (166).

[0079] The registration management engine (162) is configured to receive a DL NAS transport message including a second RID from the communicator (120). In addition, the registration management engine (162) is configured to determine that the UE (100) is registered on a 3GPP access and is waiting to enter an idle mode (IDLE mode) on the 3GPP access. In addition, upon determining to enter the idle mode, the registration management engine (162) is configured to trigger a deregistration procedure for the 3GPP access and trigger a registration procedure on the 3GPP access using the second RID. The term idle mode corresponds to a 5GMM idle mode or a 5GMM connected mode with an RRC inactivity indication, i.e., no active radio resources are allocated to the UE (100). The deregistration procedure in the specification can use a single message per access or for both accesses together.

[0080] In another embodiment, in response to receiving an indication from the critical service management engine (164) that a critical service on the non-3GPP access is active and has completed, the registration management engine (162) is configured to locally release a non-access stratum (NAS) signaling connection on the non-3GPP access. In addition, the registration management engine (162) is configured to enter an idle mode, perform a deregistration procedure, and trigger a registration procedure on the non-3GPP access using a second RID.

[0081] In response to receiving an indication of inactivity of a critical service on a non-3GPP access from a critical service management engine (164), the registration management engine (162) is configured to immediately release the NAS signaling connection on the non-3GPP access and enter an idle mode. In addition, the registration management engine (162) is configured to perform a deregistration procedure and trigger a registration procedure on the non-3GPP access using a second RID.

[0082] In another embodiment, the registration management engine (162) is configured to process a deregistration request received from one of: at least one upper layer above the NAS layer and a wireless communication network.

[0083] The key service management engine (164) is configured to determine whether the key service is active on the non-3GPP access. In addition, in response to determining that the key service is active on the non-3GPP access, the key service management engine (164) is configured to wait for completion of the key service on the non-3GPP access and indicate the completion of the key service on the non-3GPP access to the registration management engine (162).

[0084] Furthermore, in response to determining that the critical service is not active on the non-3GPP access, the critical service management engine (164) is configured to indicate to the registration management engine (162) that the critical service is not active on the non-3GPP access.

[0085] In one embodiment, the NAS transmission management engine (166) is configured to determine a transmission failure of an uplink non-access stratum (UL NAS) transmission message, and determine whether the transmission failure of the UL NAS transmission message is accompanied by a TAI change from a lower layer.

[0086] In addition, the NAS transmission management engine (166) is configured to determine a method for handling a failure of an uplink non-access stratum (UL NAS) transmission message initiated by the UE when it is determined that the failure of transmission of the UL NAS transmission message is not accompanied by a TAI change from a lower layer. In order to determine the method for handling a failure of an UL NAS transmission message initiated by the UE, the NAS transmission management engine (166) determines whether a current TAI is in a TAI list transmitted by the wireless communication network, and performs one of the following: in response to determining that the current TAI is not in the TAI list transmitted by the wireless communication network, aborting transmission of the UL NAS transmission message by the UE (100) and initiating a procedure for mobility and periodic registration update, and in response to determining that the current TAI is not in the TAI list transmitted by the wireless communication network, identifying that the UL NAS transmission message is not successfully transmitted, initiating a registration procedure, and retrying to transmit the UL NAS transmission message based on the identification that the UL NAS transmission message is not successfully transmitted after completing the registration procedure. Furthermore, the NAS transmission management engine (166) is further configured to determine a method for re-performing an ongoing procedure for triggering a UL NAS transmission procedure when it is determined that a transmission failure of the UL NAS transmission message is accompanied by a TAI change from a lower layer.

[0087] In another embodiment, the processor (160) is configured to receive a second routing ID (RID) and an indication to initiate a registration procedure using the second RID from a first unified data management (UDM) (300a), and determine that the UE (100) is registered on a non-3GPP access and there are no ongoing emergency services (or critical services) on the non-3GPP access. In addition, the processor (160) is configured to locally release the N1 NAS signaling connection and enter a 5GMM idle mode on the non-3GPP access, perform a deregistration procedure, delete the 5G-GUTI when registering the UE (100) to a different PLMN on the 3GPP access or the UE (100) is not registered on the 3GPP access, and then initiate a registration procedure for initial registration.

[0088] In another embodiment, when a DL NAS transport message with a second routing ID is received and if a critical service is ongoing on a 3GPP access or a non-3GPP access, the UE (100) will not perform a second routing ID update procedure and wait for the UE (100) to complete the critical service. Upon completion of the critical service, the UE (100) triggers the proposed method.

[0089] In another embodiment, the UE (100) performs a deregistration procedure for both accesses together (if the UE is registered on the same PLMN on both accesses) and performs an initial registration procedure on each access using the second routing ID, i.e., deleting the currently allocated GUTI, recalculating the SUCI using the second routing ID and using it during the initial registration procedure. In another embodiment, the processor (160) is configured to receive a second routing ID (RID) and an indication to initiate a registration procedure using the second RID from a first unified data management (UDM) (300a), and determine that the UE (100) is registered on a non-3GPP access and has an ongoing emergency service (or critical service) on the non-3GPP access. Furthermore, the processor (160) is configured to wait until the emergency service is completed before locally releasing the N1 NAS signaling connection and entering 5GMM idle mode on non-3GPP access, performing a deregistration procedure, deleting the 5G-GUTI when registering the UE (100) to a different PLMN on a 3GPP access or when the UE (100) is not registered on a 3GPP access, and then initiating a registration procedure for an initial registration.

[0090] In another embodiment, a UE (100) is connected on both a 3GPP access and an N3GPP access and a RID update with a requested registration is received on one access. The conventional defined behavior of the UE (100) is to perform a deregistration and then register on the access where the message was received. The behavior is not defined for alternating accesses, which leads to a mismatch of UE (100) contexts for 3GPP and N3GPP on the wireless network (e.g. 2 UDMs each maintain a UE context for one access), especially when the UE (100) is connected to a single access and mobility management function (AMF) (holding a single pointer to the UDM / AUSF instance) through both accesses. The proposed solution handles the above scenario where both confirmations are sent and synchronization is achieved between the two accesses.

[0091] In another embodiment, the UE (100) receives a new RID and a set REG bit requesting confirmation on a 3GPP access. Conventionally, the UE (100) sends the confirmation using an UL NAS transport message and, when entering idle mode, follows the defined procedure for performing a deregistration followed by a registration (on the access on which the DL NAS transport message was received).

[0092] In addition, the configuration mismatch between the UE (100) (3GPP, N3GPP) and the wireless communication network due to RID update can also be resolved in the following way: the UE (100) performs deregistration for both 3GPP and N3GPP accesses after entering 3GPP idle mode and when there is no data activity in N3GPP (although N3GPPA is not in idle mode).

[0093] In another embodiment, after both the 3GPP access and the N3GPP access enter idle mode, the UE (100) performs deregistration from both the 3GPP access and the N3GPP access so that no data activity is interrupted.

[0094] In yet another embodiment, the UE (100) continues the defined procedure on the 3GPP access and determines when the UE (100) enters idle mode on the N3GPP access. In response to determining that the UE (100) has entered idle mode on the N3GPP access, the UE (100) triggers a deregistration procedure on the N3GPP access using the new GUTI received during the registration procedure on the 3GPP access and then performs an initial registration procedure.

[0095] In yet another embodiment, after entering the 3GPP idle mode, the UE (100) performs deregistration regardless of the N3GPP access state, and then performs registration for both 3GPP access and N3GPP access.

[0096] In another embodiment, when the alternative access enters the idle state, the UE (100) immediately terminates the NAS signaling connection on both the 3GPP access and the N3GPP access or at least terminates the NAS signaling connection on one of the accesses, performs deregistration, and then performs registration for both the 3GPP access and the N3GPP access, that is, decides to terminate one or both access N1 signaling connections to enter the idle mode and initiate an initial registration process, or waits for a specific important ongoing service to be completed, and then terminates one or both 3GPP access and N3GPP access N1 signaling connections to enter the idle mode, and then initiates the initial registration process.

[0097] although Figure 1 The hardware elements of the UE (100) are shown, but it should be understood that other embodiments are not limited thereto. In other embodiments, the UE (100) may include fewer or more elements. In addition, the labels or names of the elements are only for illustrative purposes and do not limit the scope of the present disclosure. One or more components may be combined together to perform the same or substantially similar functions.

[0098] Figure 2AA flow chart (200a) of a method for performing RID update in a UE (100) in a wireless communication network according to embodiments as disclosed herein is shown.

[0099] See also Figure 2A At step 202a, the UE (100) receives from the first UDM (300a) a second RID and an instruction to initiate a registration procedure using the second RID. Figure 1 In the illustrated UE (100), the communicator (120) may be configured to receive from the first UDM (300a) a second RID and an indication to initiate a registration procedure using the second RID.

[0100] At step 204a, the UE (100) determines that the UE (100) is registered on a 3GPP access. Figure 1 In the illustrated UE (100), the processor (160) may be configured to determine that the UE (100) is registered on a 3GPP access.

[0101] At step 206a, the UE (100) performs a RID update in the UE (100) by waiting to enter an idle mode on a 3GPP access. Figure 1 In the illustrated UE (100), the processor (160) may be configured to perform a RID update in the UE (100) by waiting to enter an idle mode on a 3GPP access.

[0102] At step 208a, the UE (100) triggers a deregistration procedure for 3GPP access. Figure 1 In the illustrated UE (100), the processor (160) may be configured to trigger a deregistration procedure regarding 3GPP access.

[0103] At step 210a, the UE (100) triggers a registration procedure on the 3GPP access using the second RID. Figure 1 In the illustrated UE (100), the processor (160) may be configured to trigger a registration procedure using a second RID on a 3GPP access.

[0104] The various actions, behaviors, boxes, steps, etc. in the method can be performed in the order presented, in a different order, or simultaneously. In addition, in some embodiments, some actions, behaviors, boxes, steps, etc. can be omitted, added, modified, skipped, etc. without departing from the scope of the present disclosure.

[0105] Figure 2B A flow chart (200b) is shown illustrating a method for performing RID update over N3GPP access in a UE (100) in a wireless communication network according to embodiments as disclosed herein.

[0106] See also Figure 2B At step 202b, the UE (100) receives the second RID and an instruction to initiate a registration procedure using the second RID from the first UDM (300a). Figure 1 In the illustrated UE (100), the communicator (120) may be configured to receive from the first UDM (300a) a second RID and an indication to initiate a registration procedure using the second RID.

[0107] At step 204b, the UE (100) determines that the UE (100) is registered on the N3GPP access. Figure 1 In the illustrated UE (100), the processor (160) may be configured to determine that the UE (100) is registered on an N3GPP access.

[0108] At step 206b, the UE (100) determines whether critical services are active on the non-3GPP access. Figure 1 In the illustrated UE (100), the processor (160) may be configured to determine whether critical services are active on the non-3GPP access.

[0109] In response to determining that the critical service is active on the non-3GPP access, at step 208b, the UE (100) waits for completion of the critical service on the non-3GPP access. Figure 1 In the illustrated UE (100), the processor (160) may be configured to wait for completion of a critical service on a non-3GPP access.

[0110] At step 210b, the UE (100) locally releases the NAS signaling connection on the non-3GPP access and enters idle mode. Figure 1 In the illustrated UE (100), the processor (160) may be configured to locally release the NAS signaling connection on the non-3GPP access and enter an idle mode.

[0111] At step 212b, the UE (100) performs a deregistration procedure. Figure 1 In the illustrated UE (100), the processor (160) may be configured to perform a deregistration procedure.

[0112] At step 214b, the UE (100) triggers a registration procedure on the non-3GPP access using the second RID. Figure 1 In the illustrated UE (100), the processor (160) may be configured to trigger a registration procedure using a second RID on a non-3GPP access.

[0113] In response to determining that the critical service is not active on the non-3GPP access, at step 216b, the UE (100) immediately releases the NAS signaling connection on the non-3GPP access and enters idle mode. Figure 1 In the illustrated UE (100), the processor (160) may be configured to immediately release the NAS signaling connection on the non-3GPP access and enter an idle mode.

[0114] At step 218b, the UE (100) performs a deregistration procedure. Figure 1 In the illustrated UE (100), the processor (160) may be configured to perform a deregistration procedure.

[0115] At step 220b, the UE (100) triggers a registration procedure on the non-3GPP access using the second RID. Figure 1 In the illustrated UE (100), the processor (160) may be configured to trigger a registration procedure using a second RID on a non-3GPP access.

[0116] The various actions, behaviors, boxes, steps, etc. in the method can be performed in the order presented, in a different order, or simultaneously. In addition, in some embodiments, some actions, behaviors, boxes, steps, etc. can be omitted, added, modified, skipped, etc. without departing from the scope of the present disclosure.

[0117] Figure 2C A flow chart (200c) is shown illustrating a method for handling a UE initiated uplink non-access stratum (UL NAS) transmission message failure in a wireless communication network according to embodiments as disclosed herein.

[0118] See also Figure 2C At step 202c, the UE (100) determines that the transmission of the UL NAS transmission message has failed. Figure 1 In the illustrated UE (100), the processor (160) may be configured to determine a transmission failure of a UL NAS transmission message.

[0119] At step 204c, the UE (100) determines whether the delivery failure of the UL NAS transport message is accompanied by a TAI change from the lower layer. Figure 1 In the illustrated UE (100), the processor (160) may be configured to determine whether a transmission failure of a UL NAS transmission message is accompanied by a TAI change from a lower layer.

[0120] At step 206c, in response to determining that the transmission failure of the UL NAS transmission message is accompanied by a TAI change from the lower layer, the UE (100) determines a method for re-performing the ongoing procedure for triggering the UL NAS transmission procedure. Figure 1 In the illustrated UE (100), the processor (160) may be configured to determine a method for re-performing an ongoing procedure for triggering a UL NAS transmission procedure in response to determining that a transmission failure of a UL NAS transmission message is accompanied by a TAI change from a lower layer.

[0121] At step 208c, in response to determining that the transmission failure of the UL NAS transmission message is not accompanied by a TAI change from a lower layer, the UE (100) determines a method for handling a UE-initiated uplink non-access stratum (UL NAS) transmission message failure. Figure 1 In the illustrated UE (100), the processor (160) may be configured to determine a method for handling a UE-initiated uplink non-access stratum (UL NAS) transmission message failure in response to determining that the transmission failure of the UL NAS transmission message is not accompanied by a TAI change from a lower layer.

[0122] The various actions, behaviors, boxes, steps, etc. in the method can be performed in the order presented, in a different order, or simultaneously. In addition, in some embodiments, some actions, behaviors, boxes, steps, etc. can be omitted, added, modified, skipped, etc. without departing from the scope of the present disclosure.

[0123] Figure 3A The present invention shows a situation in which a UE (100) in a wireless communication network performs a routing ID update to switch from a first UDM (300a) to a second UDM (300b) according to the prior art.

[0124] Typically, in a 5G system, a unified data management (UDM) entity maintains a context of a UE (100), the context including information such as that the UE (100) has registered with an access and mobility management function (AMF) (200), that the UE (100) has received data packets from a session management function (SMF), etc. Since 5GS supports a UE (100) to be registered on both 3GPP access and N3GPP access, the UDM entity stores contexts of the UE on both 3GPP access and N3GPP access.

[0125] See also Figure 3A , at step 1, consider that the UE (100) is locked to the first UDM (300a), and the UE context associated with both 3GPP access and N3GPP access is stored at the first UDM (300a).

[0126] At step 2, the first UDM (300a) shares the RID update to the UE (100) by sending a DL NAS transport message on the 3GPP access with the REG bit set, the transport message including the second RID requesting an ACK. The second RID is a pointer to the second UDM (300b) that the 5GS wants the UE (100) to latch onto.

[0127] At step 3a, the UE (100) sends an UL NAS transfer message to the first UDM (300a) on the 3GPP access in response to receiving the DL NAS transfer message from the first UDM (300a) to trigger a UL NAS transfer process that may be aborted or failed, and at step 3b, the UE (100) deregisters from the first UDM (300a) only on the 3GPP access. Since the UE (100) deregisters only on the 3GPP access, at step 4, the UE context associated with the 3GPP access is deleted at the first UDM (300a).

[0128] At step 5, the UE (100) is still connected to the first UDM (300a) on the N3GPP access and the UE context associated with the N3GPP access is stored at the first UDM (300a). At step 6, due to the new SUCI on 3GPP after the registration process (RID update), the UE (100) registers with the second UDM (300b) and connects to the second UDM (300b) for 3GPP access.

[0129] At step 7, the UE context associated with the 3GPP access is transferred from the first UDM (300a) to the second UDM (300b). Therefore, the second UDM (300b) stores the UE context associated with the 3GPP access.

[0130] When the first UDM (300a) shares the second RID of the second UDM (300b), it is desired that the UE context associated with both 3GPP access and N3GPP access is also transferred from the first UDM (300a) to the second UDM (300b).

[0131] The conventional RID update process does not take into account the services being performed at the UE (100). When the first UDM (300a) initiates the RID update process, the first UDM (300a) does not know which services the UE (100) is currently performing. In addition, the RID update process does not take into account the current registration status of the UE (100), that is, whether the UE (100) is registered on both 3GPP access and non-3GPP access, or only one access is registered, etc. Therefore, the conventional RID update process results in fragmented UE contexts being stored across multiple UDMs, that is, the UE context associated with the 3GPP access is stored at the second UDM (300b), and the UE context associated with the N3GPP access is stored at the first UDM (300a). The fragmented UE context may cause a configuration mismatch between the UE (100) and the 5GS, or cause synchronization problems between the UE (100) and the 5GS, thereby causing abnormal behavior of both the UE (100) and the 5GS.

[0132] Figure 3B A scenario is shown in which a UE (100) in a wireless communication network performs a routing ID update to switch from a first UDM (300a) to a second UDM (300b) according to an embodiment as disclosed herein.

[0133] See also Figure 3B , combined with Figure 3A , Figure 3A Steps 1 to 3a in Figure 3B Steps 1 to 3a in are substantially the same, and thus repeated descriptions are omitted.

[0134] At step 4, the first UDM (300a) deletes both the UE context associated with the 3GPP access and the UE context associated with the non-3GPP access and transfers them to the second UDM (300b).

[0135] At step 5, the UE (100) registers with the second UDM (300b) and connects with the second UDM (300b) for 3GPP access and N3GPP access using new SUCI (RID update) on 3GPP access after the registration process.

[0136] In addition, before deregistering from the N3GPP access, the UE (100) determines whether any critical services are active on the non-3GPP access. In response to determining that the critical services are active on the non-3GPP access, the UE (100) waits for completion of the critical services on the non-3GPP access and then releases a non-access stratum (NAS) signaling connection with a first UDM (300a) on the non-3GPP access. In addition, the UE (100) enables an idle mode on the non-3GPP access, deregisters from the first UDM (300a) on the non-3GPP access, and then registers with a second UDM (300b) on the non-3GPP access. In response to determining that the critical services are not active on the non-3GPP access, the UE (100) releases the NAS signaling connection with the first UDM (300a) on the non-3GPP access and enables an idle mode on the non-3GPP access. Furthermore, the UE (100) deregisters from the first UDM (300a) on the non-3GPP access and registers with the second UDM (300b) on the non-3GPP access.

[0137] Therefore, unlike conventional RID update, the proposed method considers ongoing critical services at the UE (100) before deregistering from the first UDM (300a).

[0138] In addition, the proposed method transfers the UE context associated with the 3GPP access and the UE context associated with the N3GPP access from the first UDM (300a) to the second UDM (300b). Therefore, the proposed method does not provide for fragmented storage of the UE context, which results in context mismatches in the UE (100).

[0139] In another embodiment, after entering 3GPP idle mode and when there is no data activity on N3GPP access (although N3GPPA is not in idle mode), the UE (100) performs deregistration for both 3GPP access and N3GPP access.

[0140] In another embodiment, after both the 3GPP access and the N3GPP access enter the idle state, the UE (100) performs deregistration for both the 3GPP access and the N3GPP access, so that no data activity is interrupted. In another embodiment, after entering the 3GPP idle mode, the UE (100) performs deregistration regardless of the N3GPP access state, and then performs registration for both the 3GPP access and the N3GPP access.

[0141] In another embodiment, when the alternative access enters the idle state, the UE (100) immediately terminates the NAS signaling connection on both the 3GPP access and the N3GPP access or at least terminates the NAS signaling connection on one of the accesses, performs deregistration, and then performs registration for both the 3GPP access and the N3GPP access, that is, decides to terminate one or both access N1 signaling connections to enter the idle mode and initiate an initial registration process, or waits for a specific important ongoing service to be completed, and then terminates one or both access N1 signaling connections to enter the idle mode, and then initiates the initial registration process.

[0142] The proposed method is applicable to both accesses, i.e., if the RID change occurs on 3GPP, the N3GPP must be updated, and if the RID change occurs on N3GPP, the 3GPP access must be updated. The proposed method is applicable even in the inactive state, i.e., whenever the idle state is specified, it can be replaced by the inactive state. The deregistration procedure in the proposed method can be implemented per access or for both accesses using a single message.

[0143] Figure 4A A situation is shown in which a UE (100) according to the prior art does not send an acknowledgement in a UL NAS transmission message, thereby causing a mismatch in UE configuration between the UE (100) and the wireless communication network.

[0144] Generally, there are two types of NAS transmission procedures defined in the 3GPP 5G NAS specification (24.501) for transmitting message payload and associated information between the UE (100) and the wireless network. The two NAS transmission procedures are the UE initiated NAS transmission (UL NAS transmission) procedure and the wireless network initiated NAS transmission (DL NAS transmission) procedure, which are "independent" procedures. The current 3GPP protocol assumes that the UE initiated NAS transmission procedure is retried by the upper layer (layer above the NAS layer) in cases such as SMS. However, there are various cases, such as the UE (100) receiving a SOR message requesting confirmation, and then a UE parameter update (for parameters such as routing ID, slice information, etc.) requesting confirmation via the UDM control plane, etc., where a retry may not be attempted if the process fails.

[0145] See also Figure 4A In conventional methods and systems, the UE (100) does not send an acknowledgement for a UL NAS transmission message, which may cause a mismatch in configuration between the UE (100) and the wireless network or cause a synchronization problem between the UE (100) and the wireless network, thereby causing abnormal behavior of both the UE (100) and the wireless communication network that needs to be resolved. In addition, various exemplary scenarios are described below, which reflect the mismatch in configuration between the UE (100) and the wireless network.

[0146] Consider an example of a UE parameter update procedure, i.e., a first UDM (300a) updates a new RID in a DL NAS transfer message containing a request confirmation indication received via an AMF (200). After verifying the message from the wireless network, the UE (100) updates the new RID, generates a new subscription concealment identifier (SUCI), and initiates a UL NAS transfer message to send a confirmation to the wireless network. However, a failure in the transmission of the UL NAS transfer message will result in a mismatch in configuration between the UE (100) and the wireless network.

[0147] Consider another example of radio link failure (RLF) no service, due to which the UL NAS transmission process is aborted and a recovery process is performed. After the service is restored, the UE (100) never sends an acknowledgment in the UL NAS transmission message because there is no defined method for sending the acknowledgment again because the current state machine does not support the aborted process. Therefore, a mismatch is generated regarding the UE configuration between the UE (100) and the wireless network.

[0148] In yet another exemplary case of a cell change belonging to a different Tracking Area Identifier (TAI) due to a change of cells belonging to a different Registration Area / Tracking Area, the UE (100) aborts the UL NAS transmission procedure and initiates a Mobility Registration Update procedure. After completing the Registration Update procedure, there is no method defined for the UE (100) to re-initiate the aborted procedure, resulting in a mismatch of UE configuration between the UE (100) and the wireless network.

[0149] In another exemplary case of failure in (re)transmission of a UL NAS transfer message, the UE (100) sends a UL NAS transfer message but does not receive an L2 confirmation. The UE (100) considers the process to have failed and continues to use the old RID, although the wireless network maintains the new RID by deleting the old RID because the NAS transfer process is an independent process, or the UE (100) starts using the new RID, but the wireless network considers the process to have failed because the confirmation has not been received and maintains the old RID for the UE (100); thereby causing a mismatch in UE configuration between the UE (100) and the wireless network.

[0150] In all of the above exemplary cases, the RID ambiguity between the UE (100) and the wireless network results in unexpected behavior and mismatches in configuration between the UE (100) and the wireless network, thereby affecting subsequent processes like authentication.

[0151] Figure 4BVarious scenarios are shown in which a UE (100) replays an ongoing procedure that triggers a UE-initiated NAS transfer procedure according to embodiments as disclosed herein.

[0152] In the proposed method, the UE (100) is configured to handle attempts for UE initiated NAS procedures (UL NAS transport messages) depending on whether upper layer (layers above NAS) retry is possible (ie based on UE implementation). Furthermore, the method is also applicable to exemplary cases, such as a failure in transmission of a UE-initiated NAS transmission message with a TAI change or a case where no TAI change indication is received from lower layers, and therefore a (re)transmission attempt may not occur (i.e., without the proposed change, the UE (100) will not retry transmission of the UL NAS transmission message in the described situation. An abnormal case in the UE (100) is a failure in transmission of a UL NAS transmission message with a TAI change from lower layers. If the current TAI is not in the TAI list, the UE-initiated NAS transmission procedure may be aborted and a registration procedure for mobility and periodic registration update may be initiated. After the successful mobility and periodic registration update procedure, the UL NAS transmission message may be sent if still needed. If the current TAI is still part of the TAI list, the UE (100) decides based on the UE implementation to re-run the method of the ongoing procedure that triggered the UE-initiated NAS transmission procedure. Another example of an abnormal case in the UE (100) is a failure in transmission of a UL NAS transmission message with a TAI change from lower layers. A method for indicating a delivery failure indicated by a NAS transfer message, wherein the UE (100) decides based on UE implementation to re-run the ongoing procedure that triggered the UE-initiated NAS transfer procedure.

[0153] In abnormal situations, where the upper layers cannot control the re-initiation of the UL NAS transmission procedures (SoR, UDM parameter update procedures, etc.), various UE-specific implementation methods are proposed to handle the ambiguity caused by the UL NAS transmission procedures.

[0154] In a first UE-specific implementation method, when the UE (100) has to trigger or transmit an UL NAS transfer message, the UE (100) needs to define and maintain a state or sub-state based on the implementation, (e.g., UL_NAS_TRANS_ATTEMPTING), which indicates that the UE-initiated NAS transfer process is triggered and waits for a confirmation (L2ACK) of successful transmission or any response to the message based on the situation that triggered the process. In addition, after receiving the confirmation of the successful transmission of the message, the UE (100) is configured to change the sub-state back to the initial state (e.g., UL_NAS_TRANS_INIT), which indicates that the UL NAS transfer message is not pending or the process is successful and thus returns to the initial state. If there is no L2 confirmation for the UL NAS transfer message from the wireless network, the process is deemed to have failed and retries to maintain the current state until the maximum number of attempts (controlled by an attempt counter) is exhausted. If the maximum number of retransmission attempts fails, the process is deemed to have failed and the process is aborted according to current standards and the state is changed back to the initial state (e.g., UL_NAS_TRANS_INIT).

[0155] For example, considering that a periodic registration timer expires during an ongoing UL NAS transmission procedure, the UE-initiated NAS transmission procedure is then aborted and a registration update procedure is performed. In addition, the UE (100) maintains the internal state / sub-state of the aborted UL NAS transmission procedure and retries the procedure after the registration update is successful.

[0156] See also Figure 4B , a similar situation is provided where the UE (100) triggers the transmission of an UL NAS transfer message. At steps 3 and 4, when the UE (100) attempts to send an UL NAS transfer message (confirmation), the UL NAS transfer procedure fails. At step 5, the UE (100) triggers a periodic registration, due to which the state changes from the 5GMM_REGISTERED state to the 5GMM-REGISTERED_INITIATED state. In addition, at step 6, the periodic registration update is completed, but the current state transition from 5GMM-REGISTERED_INITIATED to 5GMM_REGISTERED does not support the sending of an UL NAS transfer message before the update. Therefore, once the update is completed, at step 7, the UE (100) retransmits the UL NAS transfer message (confirmation).

[0157] In any similar situation, the status / sub-status check may be performed after the 3GPP defined procedures have been completed.

[0158] A second UE-specific implementation method for handling a UE-initiated NAS transmission procedure includes maintaining a global variable at the UE (100). When the UE (100) initiates the procedure, the global variable is set to 1 (e.g., ul_nas_trans_triggered=0 / 1, 0 indicates no procedure, 1 indicates that the procedure is triggered), and the global variable is not changed until a confirmation of successful transmission or any response to the message is received according to the situation in which the UE-initiated NAS transmission procedure is triggered. In addition, after receiving the confirmation of successful transmission of the message, the UE (100) sets the global variable to 0, thereby indicating that no procedure is triggered or the procedure is successful and returns to an initial state. In addition, the UE (100) handles the different possible situations mentioned according to the first UE-specific implementation method and the second UE-specific implementation method by retaining the value set in the global variable and changing the value of the global variable to 0 or the initial state only when the process is declared successful or failed.

[0159] A third UE-specific implementation method for handling a UE-initiated NAS transfer procedure includes maintaining NV / EFS items at the UE (100). The third UE-specific implementation method is similar to the second UE-specific implementation method, except that instead of maintaining a global variable, the UE (100) maintains one of an NV item, an EFS item, or an item related to performing the same actions proposed in various UE-specific implementation methods for handling abnormal situations of a UE-initiated NAS transfer procedure.

[0160] The proposed method is also applicable when the UE (100) is turned off or restarted for any reason during the transmission of the UL NAS transfer message. Considering that the UE (100) is turned off or the restart option is selected, an NV item indicating the abort of the ongoing UE-initiated NAS transfer process is stored together with the payload. When the UE (100) is powered on and registered with the wireless network immediately and / or after T time (optionally based on the implementation), the UE (100) attempts to retransmit the aborted UL NAS transfer process. If the timer T expires before the UE (100) is able to register with the network, the NV / EFS item is discarded and the payload optionally performs no further actions related to it. In addition, if the retransmission fails and the maximum number of attempts is exhausted, the process is declared as failed and the process is aborted according to current standards, and any stored NV / EFS items and payload will be discarded.

[0161] Figure 5A A situation is shown in which a UE (100) according to the prior art does not re-initiate an aborted UL NAS transmission procedure after completing a registration update procedure in a wireless network.

[0162] See also Figure 5A, at step 1, it is considered that the UE (100) is registered with a registration represented by Tracking Area Identity 1 (TAI 1), and the UDM (300) sends a DL NAS transfer message requesting confirmation. At step 2, in response to the DL NAS transfer message sent by the UDM (300), the UE (100) transmits a UL NAS transfer message to the UDM (300). However, at step 3, due to the mobility of the UE (100), the TAI changes from TAI 1 to TAI 2. Due to the TAI change, the UE (100) aborts the ongoing UL NAS transfer message and performs a registration update procedure by sending a registration update message, as shown in step 4. However, since there is a process that causes synchronization problems, there is an existing method defined to re-initiate the aborted UL NAS transfer process during a state machine change.

[0163] Figure 5B A scenario is shown in which a UE (100) according to an embodiment as disclosed herein re-initiates an aborted UL NAS transmission procedure after completing a registration update procedure in a wireless network.

[0164] See also Figure 5B , at step 1, the UE (100) registered in TAI 1 receives a DL NAS transfer message requesting confirmation from the UDM (300). At step 2, in response to the DL NAS transfer message sent by the UDM (300), the UE (100) transmits a UL NAS transfer message to the UDM (300). However, at step 3, due to the mobility of the UE (100), the TAI changes from TAI 1 to TAI 2. Due to the TAI change, the UE (100) aborts the ongoing UL NAS transfer message and performs a registration update procedure by sending a registration update message, as shown in step 4. At step 5, after completing the registration update procedure from the TAI 2 location, the UE (100) re-initiates the aborted UL NAS transfer procedure by sending a UL NAS transfer message to the UDM (300).

[0165] Fig. 6A A situation is shown in which a UE (100) according to the prior art does not re-initiate an aborted UL NAS transmission procedure due to processing of a deregistration procedure triggered by a wireless network.

[0166] See also Fig. 6A Considering that the UDM (300) of the wireless network sends a DL NAS transfer message requesting confirmation to the UE (100). At step 2a, the UE (100) sends the DL NAS transfer message to a universal integrated circuit card (UICC) present in the UE (100) to update the UICC with the RID. At step 2b, in response, a UICC refresh command is received.

[0167] At step 3, the UE (100) initiates a UL NAS transfer message and fails. However, since the wireless network sends a deregistration request to the UE (100), retrying to transmit the UL NAS transfer message is not possible. At step 4, the UE (100) receives a deregistration request message from the UDM (300). Due to the deregistration request message, the UL NAS transfer procedure is aborted and the deregistration procedure is processed. During the update of UE parameters via the UDM control plane procedure, the routing ID (RID) can be updated with the requested confirmation using the NAS transfer procedure defined by 3GPP.

[0168] However, there is a situation where the UL NAS transmission process is aborted or fails, and another situation where a conflict with deregistration may occur. In the case of a conflict with deregistration, the UE (100) triggers a UL NAS transmission message and fails. At the same time, the UDM (300) of the wireless network sends a deregistration request message, or triggers deregistration from an upper layer, thereby causing a conflict between the two processes. The UL NAS transmission process is aborted (and any further retry of the UL NAS transmission process is stopped), and the deregistration process is first processed according to the current standard protocol. However, due to the abort of the UL NAS transmission process, a mismatch in configuration between the UE (100) and the wireless network is caused, or a synchronization problem is caused between the UE (100) and the wireless network, resulting in abnormal behavior of both the UE (100) and the wireless network.

[0169] Figure 6B A scenario is shown in which a UE (100) according to an embodiment as disclosed herein re-initiates an aborted UL NAS transmission procedure and then handles a deregistration procedure triggered by the wireless network.

[0170] See also Figure 6B , combined with Fig. 6A , raises the issue caused by the conflict between the deregistration procedure triggered by the wireless network and the retry of the aborted UL NAS transmission procedure. In addition, Figure 6B Steps 1 to 2b in Fig. 6A Steps 1 to 2b in are substantially the same, and thus repeated descriptions are omitted.

[0171] In the proposed method, at step 3, the UE (100) does not send a confirmation message to the wireless network until the UICC sends a refresh command. In addition, the UE (100) initiates a UL NAS transmission message, but fails and prepares to retry. However, at the same time as step 4, the wireless network sends a deregistration request message to the UE (100). Although the UE (100) receives the deregistration request, the UE (100) completes the UL NAS transmission procedure, which is confirmed when the L2 ACK message for the successful (re)transmission of the UL NAS transmission message sent in step 5 is received. In addition, at step 6, the UE (100) processes the deregistration procedure. Therefore, unlike conventional methods and systems, in the proposed method, when there is a conflict between the UE's UL NAS transmission message (for example, due to a failure during the first attempt) and the deregistration request message from the wireless network, the UE (100) continues the ongoing UL NAS transmission procedure and then processes the deregistration request from the wireless network. If the UICC does not send a refresh command at step 2b, the ME may store the UL NAS transport message or send a UL NAS transport message after receiving a refresh message until the UE (100) is powered off or discard the UL NAS transport message to restore the previous configuration after the UE (100) is powered off.

[0172] Fig. 7A A situation is shown in which a UE (100) according to the prior art does not re-initiate an aborted UL NAS transmission procedure due to processing of a deregistration procedure triggered by an upper layer.

[0173] See also Fig. 7A , at step 1, the UDM (300) of the wireless network considers that the DL NAS transfer message requesting confirmation is sent to the UE (100). At step 2a, the UE (100) sends the DL NAS transfer message to a universal integrated circuit card (UICC) present in the UE (100) to update the UICC with the RID. At step 2b, in response, the UE (100) receives the UICC refresh command, and the UE (100) wants to send the UL NAS transfer message. However, at the same time, at step 3, the upper layer initiates the deregistration request message. Since the upper layer initiates the deregistration procedure, the UE (100) does not initiate the UL NAS transfer procedure, and the deregistration procedure is processed.

[0174] Figure 7B A scenario is shown in which a UE (100) according to an embodiment as disclosed herein re-initiates an aborted UL NAS transmission procedure and later processes a deregistration procedure triggered by upper layers.

[0175] See also Figure 7B , combined with Fig. 7A, raises the problem caused by the conflict between the deregistration procedure triggered by the upper layer and the UL NAS transmission procedure. In addition, Figure 7B Steps 1 to 3 in Fig. 7A Steps 1 to 3 in the method are substantially the same, so repeated description is omitted. In the proposed method, the UE (100) does not send a confirmation message to the wireless network until the UICC sends a refresh command.

[0176] At step 3, when the UE (100) receives the deregistration request, the UE (100) also receives a UICC refresh command, and the UE (100) will initiate a UL NAS transmission message based on the refresh command. At step 4, the UE (100) sends the UL NAS transmission message to the wireless network and delays the processing of the deregistration request message sent by the upper layer. In addition, at step 5, the UE (100) receives an L2 ACK regarding the successful transmission of the UL NAS transmission message. After receiving the L2 ACK, the UE (100) processes the deregistration request received from the upper layer. Different from conventional methods and systems, in the proposed method, when there is a conflict between the UL NAS transmission message and the deregistration request message from the upper layer, the UE (100) continues the ongoing UL NAS transmission process and delays the processing of the deregistration request from the upper layer until the UL NAS transmission process is completed. After the UL NAS transmission process is completed, the UE (100) sends the deregistration message to the wireless network. Therefore, the proposed method solves the conflict problem between the deregistration process triggered by the upper layer and the ongoing UL NAS transmission process.

[0177] The embodiments disclosed herein may be implemented by at least one software program running on at least one hardware device and performing network management functions to control the elements. Figures 1 to 7B The elements shown include blocks that may be at least one of hardware devices or a combination of hardware devices and software modules.

[0178] Although the present disclosure has been described with various embodiments, various changes and modifications may be suggested to one skilled in the art. It is intended that the present disclosure encompass such changes and modifications as fall within the scope of the appended claims.

Claims

1. A method for performing a routing ID (RID) update in a user equipment UE in a wireless communication network, the method comprising: receiving from a first unified data management (UDM) a second routing ID (RID) and an indication to initiate a registration procedure using the second RID, wherein the UE is currently configured using the first routing ID (RID); Determining that the UE is registered on a non-3rd Generation Partnership Project (non-3GPP) access; Determining that critical services are active on non-3GPP access; and A routing ID (RID) update is performed in the UE in the following manner: Waiting for completion of critical services on the non-3GPP access, locally releasing a non-access stratum (NAS) signaling connection on the non-3GPP access and entering an idle mode on the non-3GPP access, Perform the logout process, and A registration procedure is triggered using the second RID on the non-3GPP access.

2. The method of claim 1, further comprising: determining that the critical service is inactive on the non-3GPP access; locally releasing the NAS signaling connection on the non-3GPP access and entering an idle mode on the non-3GPP access; Execute the deregistration process; as well as The registration procedure is triggered using the second RID on the non-3GPP access.

3. The method of claim 1, wherein the second routing ID (RID) is received in a downlink non-access stratum (DL NAS) transmission message from the wireless communication network. The method of claim 1 , wherein the critical service is an emergency service.

5. A UE for performing a routing ID (RID) update in a user equipment UE in a wireless communication network, the UE comprising: Memory; a processor coupled to the memory and configured to: receiving from a first unified data management (UDM) a second routing ID (RID) and an indication to initiate a registration procedure using the second RID, wherein the UE is currently configured using the first routing ID (RID), determining that the UE is registered on a non-3rd Generation Partnership Project (non-3GPP) access, Determine that critical services are active on non-3GPP access, and A routing ID (RID) update is performed in the UE in the following manner: Waiting for completion of critical services on the non-3GPP access, locally releasing a non-access stratum (NAS) signaling connection on the non-3GPP access and entering an idle mode on the non-3GPP access, Perform the logout process, and A registration procedure is triggered using the second RID on the non-3GPP access.

6. The UE of claim 5, wherein the processor is further configured to: determining that the critical service is inactive on the non-3GPP access; locally releasing the NAS signaling connection on the non-3GPP access and entering an idle mode on the non-3GPP access; Execute the deregistration process; and The registration procedure is triggered using the second RID on the non-3GPP access.

7. The UE of claim 5, wherein the second RID is received in a downlink non-access stratum (DL NAS) transmission message from the wireless communication network.

8. The UE of claim 5, wherein the critical service is an emergency service.

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