store-and-forward operation

Abstract

Example embodiments of the present disclosure relate to store-and-forward operations in non-terrestrial networks (NTNs). In one aspect, a first non-terrestrial network (NTN) device stores a first registration request based on receiving the first registration request from a terminal device and not having connectivity with a terrestrial network (TN) device. The first NTN device transmits an identifier assigned to the terminal device to the terminal device. In this way, registration procedures, authentication procedures, security, and UE subscription data can be supported during store-and-forward scenarios.

Description

Technical Field

[0001] The exemplary embodiments of this disclosure generally relate to the field of communications, and more particularly to apparatus, methods, devices, and computer-readable storage media for store-and-forward operations in, for example, non-terrestrial networks (NTNs). Background Technology

[0002] A communication network can be viewed as a facility that enables communication between two or more communication devices or provides communication devices with access to a data network. Mobile or wireless communication networks are an example of a communication network. Services can be provided to communication devices by an application server.

[0003] Such communication networks operate according to standards provided by organizations such as 3GPP (3rd Generation Partnership Project) or ETSI (European Telecommunications Standards Institute). An example of such a standard is the so-called 5G (fifth generation) standard provided by 3GPP. Summary of the Invention Typically, the exemplary embodiments of this disclosure provide a solution for store-and-forward operations, for example, in a non-terrestrial network (NTN), and particularly a solution for handling registration in NTN store-and-forward.

[0004] In a first aspect, a first non-terrestrial network (NTN) device is provided. The first NTN device includes at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the first NTN device to at least: store a first registration request based on receiving a first registration request from a terminal device and not having connectivity with a terrestrial network (TN) device; and transmit an identifier assigned to the terminal device to the terminal device.

[0005] In a second aspect, a terrestrial network (TN) device is provided. The TN device includes at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the TN device to at least: receive an identifier assigned to a terminal device and a first registration request from a first NTN device; and initiate authentication for the terminal device using the identifier assigned to the terminal device.

[0006] In a third aspect, a terminal device is provided. The terminal device includes at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the terminal network device to at least: transmit a first registration request to a first NTN device; and receive from the first NTN device an identifier assigned to the terminal device in response to the first registration request.

[0007] In a fourth aspect, a method is provided. The method includes: storing the first registration request based on receiving a first registration request from a terminal device and not having connectivity with a terrestrial network (TN) device; and transmitting an identifier assigned to the terminal device to the terminal device.

[0008] In a fifth aspect, a method is provided. The method includes: receiving an identifier assigned to a terminal device and a first registration request from a first NTN device; and initiating authentication for the terminal device using the identifier assigned to the terminal device.

[0009] In a sixth aspect, a method is provided. The method includes: transmitting a first registration request to a first NTN device; and receiving from the first NTN device an identifier assigned to a terminal device in response to the first registration request.

[0010] In a seventh aspect, an apparatus is provided. The apparatus includes components for: storing the first registration request based on receiving a first registration request from a terminal device and not having connectivity with a terrestrial network (TN) device; and transmitting an identifier assigned to the terminal device to the terminal device.

[0011] In an eighth aspect, an apparatus is provided. The apparatus includes components for: receiving an identifier assigned to a terminal device and a first registration request from a first NTN device; and using the identifier assigned to the terminal device to initiate authentication for the terminal device.

[0012] In a ninth aspect, an apparatus is provided. The apparatus includes: components for transmitting a first registration request to a first NTN device; and components for receiving from the first NTN device an identifier assigned to a terminal device in response to the first registration request.

[0013] In a tenth aspect, a non-transitory computer-readable medium is provided, comprising program instructions for causing a device to execute at least the method according to any one of the third to fourth aspects described above.

[0014] In the eleventh aspect, a computer program including instructions is provided that, when executed by a device, causes the device to perform at least the method according to any one of the fourth to sixth aspects described above.

[0015] In a twelfth aspect, a first network device is provided. The first network device includes a storage circuit configured to store a first registration request based on receiving a first registration request from a terminal device and not having connectivity with a terrestrial network (TN) device; and a transmission circuit configured to transmit an identifier assigned to the terminal device to the terminal device.

[0016] In a thirteenth aspect, a second network device is provided. The network device includes: a receiving circuit configured to receive an identifier assigned to a terminal device and a first registration request from a first NTN device; and an initiation circuit configured to initiate authentication of the terminal device using the identifier assigned to the terminal device.

[0017] In a fourteenth aspect, a terminal device is provided. The terminal device includes: a transmission circuit configured to transmit a first registration request to a first NTN device; and a receiving circuit configured to receive from the first NTN device an identifier assigned to the terminal device in response to the first registration request.

[0018] It should be understood that the summary portion is not intended to identify key or essential features of the embodiments of this disclosure, nor is it intended to limit the scope of this disclosure. Other features of this disclosure will become readily apparent from the following description. Attached Figure Description

[0019] Some exemplary embodiments will now be described with reference to the accompanying drawings, in which: Figure 1A Examples of network environments in which exemplary embodiments of this disclosure may be implemented are shown; Figure 1B Several operating modes associated with embodiments of this disclosure are shown; Figure 1C An example of a non-terrestrial network including non-terrestrial network nodes (e.g., satellites) and terrestrial network nodes is shown during three different time periods; Figure 1D An example of a non-terrestrial network including non-terrestrial network nodes (e.g., satellites) and terrestrial network nodes is shown during three different time periods; Figure 2 The process flow of a method according to some embodiments of the present disclosure is shown; Figure 3 Detailed examples of interaction between user equipment and satellites according to some exemplary embodiments of the present disclosure are shown; Figure 4 Detailed examples of processing flows according to some exemplary embodiments of this disclosure are shown; Figure 5 A flowchart illustrating a method performed by an apparatus according to some exemplary embodiments of the present disclosure; Figure 6 A flowchart illustrating a method performed by an apparatus according to some exemplary embodiments of the present disclosure; Figure 7 A flowchart illustrating a method performed by an apparatus according to some exemplary embodiments of the present disclosure; Figure 8A simplified block diagram of a device suitable for implementing some example embodiments of this disclosure is shown; and Figure 9 A block diagram illustrating an example of a computer-readable medium according to some exemplary embodiments of the present disclosure is shown.

[0020] In all the accompanying drawings, the same or similar reference numerals denote the same or similar elements. Detailed Implementation

[0021] The principles of this disclosure will now be described with reference to some exemplary embodiments. It should be understood that these embodiments are described for illustrative purposes only and to assist those skilled in the art in understanding and implementing this disclosure, and do not imply any limitation on the scope of this disclosure. The disclosure described herein can be implemented in various ways other than those described below.

[0022] In the following description and claims, unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains.

[0023] References to "an embodiment," "embodiment," "example embodiment," etc., in this disclosure indicate that the described embodiment may include a particular feature, structure, or characteristic, but not every embodiment must include that particular feature, structure, or characteristic. Furthermore, such phrases do not necessarily refer to the same embodiment. Additionally, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is believed that implementing such a feature, structure, or characteristic in conjunction with other embodiments, whether explicitly described or not, is within the knowledge of those skilled in the art.

[0024] It should be understood that although the terms “first” and “second”, etc., may be used herein to describe various elements, these elements should not be limited by these terms. These terms are used only to distinguish one element from another. For example, without departing from the scope of the exemplary embodiments, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element. As used herein, the term “and / or” includes any and all combinations of one or more of the listed terms.

[0025] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments. As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that, when used herein, the terms “comprises,” “comprising,” “has,” “having,” “includes,” and / or “including” specify the presence of these features, elements, and / or components, etc., but do not exclude the presence or addition of one or more other features, elements, components, and / or combinations thereof. As used herein, “at least one of the following: ” and “at least one of ” and similar wording (where the list of two or more elements is connected by “and” or “or”) means at least any one of the elements, or at least any two or more of the elements, or at least all of the elements.

[0026] As used in this application, the term "circuit" may refer to one or more of the following: (a) Hardware circuits only (e.g., analog and / or digital circuits) and (b) A combination of hardware circuitry and software, such as (if applicable): (i) A combination of analog and / or digital hardware circuitry and software (e.g., firmware); and (ii) Any part of a hardware processor having software (including (multiple) digital signal processors), software, and memory, which work together to enable a device such as a mobile phone or server to perform various functions, and (c) Hardware circuitry and / or processors, such as microprocessors or a portion thereof, which require software (e.g., firmware) to operate, but which may be absent when no software is required to operate.

[0027] This definition of "circuit" applies to all uses of the term in this application (including in any claim). As another example, as used herein, the term "circuit" also encompasses only hardware circuitry or a processor (or multiple processors) or a portion thereof and its accompanying software and / or firmware implementation. The term "circuit" also encompasses, for example and if applicable to a particular claim element, baseband integrated circuits or processor integrated circuits for mobile devices or similar integrated circuits in servers, cellular network devices, or other computing or network devices.

[0028] As used herein, the term "cellular network" refers to a network operating according to any suitable radio access technology defined by standards such as Long Term Evolution (LTE), LTE-A Advanced, New Radio, Wideband Code Division Multiple Access (WCDMA), High-Speed ​​Packet Access (HSPA), and Narrowband Internet of Things (NB-IoT). Furthermore, communication between terminal devices and network devices within the cellular network can be performed according to any suitable communication protocol, including but not limited to fourth-generation (4G), 4.5G, future fifth-generation (5G) communication protocols, and / or any other currently known or future-developed protocols. Embodiments of this disclosure can be applied to a variety of cellular networks. Given the rapid development of communications, there will naturally be communication technologies and systems that embody future types of this disclosure. The scope of this disclosure should not be construed as limited to the aforementioned systems.

[0029] As used herein, the term "network device" refers to any device in a cellular network through which terminal devices access data networks and receive services offered by other network devices in the cellular network. In some examples, a network device may include or implement the network functions of a fifth-generation communication system (5GS) (e.g., the core network) of the cellular network. In some examples, a network device may be located at the RAN of the 5GS. Depending on the terminology and technologies applied, a network device may be part of a satellite, base station (BS), or access point (AP), such as a B-node (NodeB or NB), an evolved B-node (eNodeB or eNB), an NR NB (also known as a gNB), a remote radio unit (RRU), a radio head unit (RH), a remote radio head (RRH), a relay, a low-power node (such as a femtonode), a piconode, etc. A gNB may include a centralized unit (CU) and one or more distributed units (DUs). Femtonodes and piconodes are small base stations with small coverage areas.

[0030] The term "terminal equipment" refers to equipment in a cellular network communication system, such as a fifth-generation communication system (5GS) capable of wireless (e.g., radio) communication with the NR-RAN of 5GS. As an example and not a limitation, terminal equipment may also be referred to as wireless communication equipment, user equipment (UE), subscriber station (SS), portable subscriber station, mobile station (MS), or access terminal (AT). Examples of terminal devices include, but are not limited to, mobile phones, cellular phones, smartphones, Voice over IP (VoIP) phones, wireless local loop phones, tablets, wearable terminal devices, personal digital assistants (PDAs), portable computers, desktop computers, image capture terminal devices (such as digital cameras), gaming terminal devices, music storage and playback devices, in-vehicle wireless terminal devices, wireless endpoints, mobile stations, laptop embedded devices (LEEs), laptop-mounted devices (LMEs), USB dongles, smart devices, wireless customer premises equipment (CPEs), Internet of Things (IoT) devices, watches or other wearable devices, head-mounted displays (HMDs), vehicles, drones, medical devices and applications (e.g., remote surgery), industrial devices and applications (e.g., robots and / or other wireless devices operating in the context of industrial and / or automated processing chains), consumer electronics devices, devices operating on commercial and / or industrial wireless networks, etc. In the following description, the terms "terminal device," "communication device," "terminal," "user equipment," and "UE" are used interchangeably.

[0031] Store and forward (S&F) operations provide latency-tolerant communication services to user equipment (UEs) that are under satellite coverage and have intermittent / temporary satellite connections (e.g., when the satellite is not connected to the terrestrial network via a feeder link or via an inter-satellite link (ISL)). In other words, it may not be desirable for the satellite to simultaneously have access to both a serving link (to the UE's Uu interface) and a feeder link (directly or indirectly via an ISL link) to the terrestrial network.

[0032] Store-and-forward (S&F) services are widely used in latency-tolerant and outage-tolerant networking. In the 3GPP context, one service that can be considered an S&F service is SMS. For SMS, an end-to-end connection is not required between endpoints (e.g., one endpoint could be a UE, and the other could be an application server); instead, an end-to-end connection exists only between the endpoints and the Short Message Service Center (SMSC), which acts as an intermediate node responsible for storage and relay. Support for S&F satellite operations is suitable for delivering latency-tolerant / non-real-time IoT satellite services using NGSO satellites. Another example of such a service is CIoT control plane data transmission, where 3GPP networks are used to exchange latency-tolerant data between CIoT UEs arriving via satellite access and applications located on the ground.

[0033] Several issues need to be addressed to support S&F satellite operations for such services. These include: identifying the minimum necessary set of core network elements / network functions that should be placed on satellites for the intended service; determining how to trigger and execute S&F satellite operations; identifying the necessary enhancements to relevant UE and network procedures to support S&F satellite operations; determining whether to notify the UE when applying S&F satellite operations; determining how to support the registration process during S&F scenarios; determining how to enable the authentication process for S&F scenarios; determining how to enable NAS security at the UE and core network; and determining how to ensure UE subscription data retrieval and UE context creation in the RAN.

[0034] In view of the above, exemplary embodiments of this disclosure provide a solution for store-and-forward operations in a non-terrestrial network (NTN), particularly a solution for handling registration in NTN store-and-forward. In exemplary embodiments of this disclosure, a first non-terrestrial network (NTN) device can store a first registration request based on receiving a first registration request from a terminal device and not having connectivity with a terrestrial network (TN) device. The first NTN device can also transmit an identifier assigned to the terminal device. In this way, the registration process, authentication process, security, and UE subscription data can be supported during the store-and-forward scenario.

[0035] Figure 1A An example of a network environment 100a in which exemplary embodiments of the present disclosure may be implemented is shown. Environment 100a may be part of a communication network and includes multiple terminal devices and network devices, such as a first NTN device 110, a TN device 120, and a terminal device 130. As an example, the first NTN device 110 may be implemented as a satellite (eNB), an AMF-NT (Above-Terrain Function-Near-Terrain), or a RAN-NT (Above-Terrain Radio Access Network). The TN device 120 may be implemented as a ground station, a base station (BS), an AMF-T (Above-Terrain Function-Near-Terrain), and the terminal device 130 may be implemented as a user equipment (UE) or an access terminal (AT). The terminal device 130 may communicate with and transmit various data to the first NTN device 110 and the TN device 120 via network environment 100a.

[0036] To transmit data and / or control information, terminal device 130 may perform communication with the first NTN device 110 and TN device 120. The link from the first NTN device 110 and TN device 120 to terminal device 130 is referred to as a downlink (DL), while the link from terminal device 130 to the first NTN device 110 and TN device 120 is referred to as an uplink (UL).

[0037] Despite Figure 1AThe first NTN device 110, TN device 120, and terminal device 130 are described in the communication environment 100a, but the embodiments of this disclosure can be equivalently applied to any other suitable communication devices communicating with each other. That is, the embodiments of this disclosure are not limited to... Figure 1A An exemplary scenario. In this regard, it should be noted that, although in Figure 1A The terminal device is schematically depicted as a mobile phone and the network device is schematically depicted as a satellite; however, it should be understood that these depictions are exemplary in nature and do not imply any limitation. In other embodiments, the first NTN device 110 and TN device 120 can be any other communication device, such as any other wireless communication device.

[0038] It should be understood that, such as Figure 1A The specific numbers of various communication devices and communication links shown are for illustrative purposes only and do not imply any limitation. Communication environment 100a may include any suitable number of communication devices and any suitable number of communication links for implementing embodiments of this disclosure. Furthermore, it should be understood that various wireless and wired communications (if desired) may exist between all communication devices.

[0039] Figure 1B Examples of "Normal / Default Operation" and "S&F Satellite Operation" modes 100b associated with this disclosure are shown. In "Normal or Default Satellite Operation" mode 100b-1, the signaling and data service exchange between terminal device 130 or UE and TN device or remote terrestrial network 120 via the first NTN device or satellite 110 requires both the service link and feeder link to be active simultaneously, ensuring a continuous end-to-end connection path exists between terminal device 130, the first NTN device 110, and the TN device 120 when terminal device 130 interacts with the satellite via the service link. TN device 120 can then transmit data received from terminal device 130 to external networks and IoT service endpoints 140, such as IoT application servers.

[0040] In “S&F Satellite Operation” mode 100b-2, end-to-end switching of signaling / data services is processed as a combination of two time-discontinuous steps. In step 105, signaling / data exchange occurs between terminal device 130 and first NTN device 110 without first NTN device 110 being simultaneously connected to TN device 120 (i.e., first NTN device 110 can operate the service link without an active feeder link connection). In step 107, connectivity between first NTN device 110 and the terrestrial network is established, enabling communication between first NTN device 110 and TN device 120. Therefore, first NTN device 110 moves from connecting to terminal device 130 in step 105 to connecting to TN device 120 in step 107. TN device 120 can then transmit the data received from terminal device 130 to external networks and IoT service endpoints 140, such as IoT application servers.

[0041] Figure 1C An example of a non-terrestrial network including non-terrestrial network nodes (e.g., satellites) and terrestrial network nodes is shown during three different time periods. The non-terrestrial network nodes (e.g., satellites) include non-terrestrial core network entity 112c and RAN node 105c (shown as RAN 105c), etc. The terrestrial network nodes are deployed on the ground and include terrestrial core network entities 113c, SMF 132c, UPF 134c, PCF 142c, SMSF 136c, DN 138c, and UDM 140c.

[0042] exist Figure 1C In the example shown, there are two non-terrestrial network nodes (e.g., two satellites), shown at different times T1, T2, and T3. The first non-terrestrial network node (e.g., the first satellite shown in black and solid lines) includes a first non-terrestrial core network entity (AMF-NT-1) 112c and a first RAN node 105c (shown as RAN 105c). The non-terrestrial network node (e.g., the second satellite shown in white) includes a second non-terrestrial core network entity (AMF-NT-2) 114c and a second RAN node 110c (shown as RAN 110c).

[0043] exist Figure 1CIn the example, the first non-terrestrial network node (e.g., the first satellite) has ground station connectivity when located in Rennes (e.g., when ground station 120c is within the coverage area of ​​the first non-terrestrial network node, it is connected to ground station 120c located in Rennes), and has ground station connectivity when located in Orléans (e.g., when ground station 424 is within the coverage area of ​​the first non-terrestrial network node, it is connected to ground station 124c located in Orléans), but has no ground station connectivity when crossing (e.g., passing through) Le Mans. The second non-terrestrial network node (e.g., the second satellite) has ground station connectivity when located in Rennes (e.g., when ground station 120c is within the coverage area of ​​the second non-terrestrial network node, it is connected to ground station 120c located in Rennes), and has ground station connectivity when located in Orléans (e.g., when ground station 124c is within the coverage area of ​​the second non-terrestrial network node, it is connected to ground station 124c located in Orléans), but has no ground station connectivity when crossing (e.g., passing through) Le Mans. For illustration, T1 is between 10.00 and 10.20, and T2 is between 10.40 and 11.00.

[0044] At time T1, a first non-terrestrial network node (e.g., a first satellite) comprising a first non-terrestrial core network entity (AMF-NT-1) 112c and a first RAN node 105c is providing coverage (e.g., located above) Le Mans, and a second non-terrestrial network node (e.g., a second satellite) comprising a second non-terrestrial core network entity (AMF-NT-2) 114c and a RAN node 110c is providing coverage to Rennes (e.g., located above Rennes and having a ground station connection). At time T2, the first non-terrestrial network node (e.g., the first satellite shown in black) will provide coverage to Orléans (e.g., will be located above and have a ground station connection), and the second non-terrestrial network node (e.g., the second satellite) will cover Le Mans. At time T3, the second non-terrestrial network node (e.g., the second satellite) will have a ground station connection to Orléans (e.g., will establish a connection with ground station 124c located in Orléans) and will synchronize with the terrestrial core network entity (AMF-T) 113c of the terrestrial network node.

[0045] Figure 1D An example of a non-terrestrial network including non-terrestrial network nodes (e.g., satellites) and terrestrial network nodes is shown during three different time periods. The non-terrestrial network nodes (e.g., satellites) include non-terrestrial core network entity 112d and RAN node 105d (shown as RAN 105d), etc. The terrestrial network nodes are deployed on the ground and include terrestrial core network entities 113d, SGW 132d, PGW 134d, PCRF 142c, SCEF 136c, DN 138c, and HSS 140d.

[0046] exist Figure 1D In the example shown, there are two non-terrestrial network nodes (e.g., two satellites), shown at different times T1, T2, and T3. The first non-terrestrial network node (e.g., the first satellite shown in black and solid lines) includes a first non-terrestrial core network entity (MME-NT-1) 112d and a first RAN node 105d (shown as RAN 105d). The non-terrestrial network node (e.g., the second satellite shown in white) includes a second non-terrestrial core network entity (MME-NT-2) 114c and a second RAN node 110d (shown as RAN 110d).

[0047] exist Figure 1D In the example, the first non-terrestrial network node (e.g., the first satellite) has a ground station connection when it is located in Rennes (e.g., when ground station 120d is within the coverage area of ​​the first non-terrestrial network node, it is connected to ground station 120d located in Rennes), and has a ground station connection when it is located in Orléans (e.g., when ground station 424 is within the coverage area of ​​the first non-terrestrial network node, it is connected to ground station 124d located in Orléans), but has no ground station connection when it passes through (e.g., through) Le Mans. The second non-terrestrial network node (e.g., the second satellite) has a ground station connection when it is located in Rennes (e.g., when ground station 120d is within the coverage area of ​​the second non-terrestrial network node, it is connected to ground station 120d located in Rennes), and has a ground station connection when it is located in Orléans (e.g., when ground station 124d is within the coverage area of ​​the second non-terrestrial network node, it is connected to ground station 124d located in Orléans), but has no ground station connection when it passes through (e.g., through) Le Mans. For illustration, T1 is between 10.00 and 10.20, and T2 is between 10.40 and 11.00.

[0048] At time T1, a first non-terrestrial network node (e.g., a first satellite) comprising a first non-terrestrial core network entity (MME-NT-1) 112d and a first RAN node 105d covers (e.g., is located above) Le Mans, and a second non-terrestrial network node (e.g., a second satellite) comprising a second non-terrestrial core network entity (MME-NT-2) 114d and a RAN node 110d provides coverage to Rennes (e.g., is located above Rennes and has a ground station connection). At time T2, the first non-terrestrial network node (e.g., the first satellite shown in black) will provide coverage to Orléans (e.g., will be located above and have a ground station connection), and the second non-terrestrial network node (e.g., the second satellite) will cover Le Mans. At time T3, the second non-terrestrial network node (e.g., the second satellite) will have a ground station connection to Orléans (e.g., will establish a connection with ground station 124d located in Orléans) and will synchronize with the terrestrial core network entity (AMF-T) 113d of the terrestrial network node.

[0049] Figure 2 A process flow diagram of a method according to some embodiments of the present disclosure is shown. For the purposes of discussion, process flow 200 will be described with reference to FIG1. ​​It should be understood that although process flow 200 has been described with reference to FIG1, process flow 200 can also be applied to other similar communication scenarios.

[0050] In process flow 200, terminal device 130 (e.g., UE) may transmit (205) a first registration request 202 to a first non-terrestrial network (NTN) device 110. Based on receiving (210) the first registration request 202 from the terminal device and not having connectivity with terrestrial network (TN) device 120, the first NTN device 110 may store (215) the first registration request. The first NTN device may also transmit (220) an identifier 204 assigned to the terminal device.

[0051] In some embodiments, the first NTN device may transmit the validity period of the identifier assigned to the terminal device to the terminal device 130. In some other examples, the first NTN device may assign an identifier to the terminal device based on the identifier of the first NTN device.

[0052] In some embodiments, when connected to TN device 120, the first NTN device may transmit (240) a first registration request and an identifier assigned to terminal device 130 to TN device 120. In embodiments, the first NTN device may also transmit the current location of terminal device 130 to TN device 120. This current location may have been determined by a radio access node located on a satellite connected to terminal device 130, or received from terminal device 130 in the registration request or via a radio access node located on a satellite connected to terminal device 130. Upon receiving (245) the identifier assigned to the terminal device and the first registration request 206 from the first NTN device, along with possible location information about terminal device 130, TN device 120 may initiate (235) authentication / identification for terminal device 130 and store the identifier assigned to the terminal device and the location information about terminal device 130 received from the first NTN device.

[0053] In some embodiments, the first NTN device 110 may transmit the location information of the terminal device, along with a first registration request and an identifier assigned to the terminal device, to the TN device 120.

[0054] In some other embodiments, as part of the authentication / identification of terminal device 130, TN device 120 may need to send a NAS request to terminal device 130. To this end, TN device 120 selects an instance of first NTN device 110 that will first be able to receive the NAS request from TN device 120 and transmit the NAS request to terminal device 130, and provides the NAS request, the identifier assigned to the terminal device, and location information possibly associated with terminal device 130 to the selected instance of first NTN device 110. Therefore, multiple instances of first NTN device 110 can receive a NAS request targeted at a terminal device, an identifier assigned to the terminal device, and location information possibly associated with terminal device 130 from TN device 120. In some other embodiments, the selected first NTN device 110 may be a different NTN device and corresponds to an instance of an NTN device different from one that has already sent a registration request to TN device 120. In some examples, the NAS request may correspond to an authentication request. In some other examples, the NAS request may correspond to a security mode command or a registration response. In some examples, location information associated with terminal device 130 sent from TN device 120 to first NTN device 110 can be derived from location information received from first NTN device 110.

[0055] In some examples, the first NTN device 110 can connect to the terminal device using the terminal device's identifier and transmit a NAS request targeting the terminal device to the terminal device 130. The first NTN device 110 can then receive a NAS response from the terminal device 130.

[0056] In some examples, the first NTN device 110 can connect to the terminal device 130 by paging the terminal device 130 using the identifier of the terminal device 130 received from the TN device 120 and possible location information associated with the terminal device 130; in some other examples, the first NTN device 110 can connect to the terminal device 130 by paging the terminal device 130 using the identifier of the terminal device received from the TN device 120 and the location of the terminal device 130.

[0057] In some exemplary embodiments, when there is no connectivity with a TN device, the first NTN device 110 may store NAS responses. When there is connectivity with a TN device 120, the first NTN device 110 may transmit NAS responses to the TN device 120. In some embodiments, the first NTN device 110 may include a third NTN device, and the third NTN device may receive NAS messages from the TN device 120, such as authentication requests, security mode commands for terminal devices, and identifiers assigned to the terminal devices, as well as possible location information corresponding to those devices. In some other examples, the first NTN device 110 may be a non-terrestrial access and mobility management function (AMF-NT), and the TN device 120 may be a terrestrial AMF. In some other examples, the first NTN device 110 may be a non-terrestrial mobility management entity (MME), and the TN device 120 may be a terrestrial MME.

[0058] In some embodiments, the TN device 120 may initiate authentication for a terminal device by: selecting a third network device based on a subscription permanent identifier (SUPI or IMSI) or a subscription hidden identifier (SUCI); receiving authentication data from the third network device; and storing the authentication data in correspondence with the identifier assigned to the terminal device.

[0059] In some embodiments, TN device 120 may receive location information of the terminal device from first NTN device 110, along with a first registration request and an identifier assigned to the terminal device. In some other embodiments, TN device 120 may transmit a NAS request targeting the terminal device and an identifier assigned to the terminal device 130 to a second NTN device. In some embodiments, TN device 120 may transmit a NAS request targeting the terminal device, an identifier assigned to the terminal device, and location information associated with the device to the second NTN device. In some embodiments, TN device 120 may receive a NAS response from the second NTN device. In some embodiments, terminal device 130 may receive the validity period of the identifier assigned to the terminal device from the first NTN device.

[0060] In some embodiments, terminal device 130 can connect to the second NTN device using the terminal device's identifier. In some embodiments, terminal device 130 can receive a NAS request targeted at the terminal device from the second NTN device. In some embodiments, terminal device 130 can transmit a NAS response to the second NTN device.

[0061] Figure 3 Detailed examples of interaction 300 between a user equipment (UE), a satellite (eNB), and a ground station or gNB according to some example embodiments of this disclosure are shown. It should be noted that... Figure 3 This can be considered another example of process flow 200. For example, UE305 can be an example device of terminal equipment 130, and terrestrial AMF (AMT-T) 320 can be an example device of TN equipment 120. It should be understood that these devices are described for illustrative purposes only and do not imply any limitation on the scope of this disclosure. The process will be described in detail below.

[0062] like Figure 3 As shown, when an unregistered UE 305 connects to RAN 310-2 on a store-and-forward satellite to initiate mobility management (MM) procedures (such as registration), it can receive a temporary identifier (GUTI) even if it has not yet registered. UE 305 knows via radio broadcast that the radio link corresponding to the S&F satellite will not interpret a radio link failure (shutdown) as an error (a failed registration attempt), and it can start a long timer and wait to be paged using the temporary identifier (GUTI).

[0063] When the AMF agent 310-1 on the S&F satellite transmits a NAS message (such as a registration request) from UE 305 to the primary AMF-T 320 (on the ground), it also provides the GUTI and UE location. In some embodiments, the ground-based AMF-T 320 has received or determined the next NAS message to be sent to the UE (e.g., an authentication challenge from AUSF), and it can determine the most suitable S&F satellite to subsequently contact UE 305. For example, the AMF-T 320 may determine the most suitable S&F satellite as having the shortest time, and the shortest time may be equal to the sum of the time to obtain a feeder link to that S&F satellite and the time that the S&F satellite has a service link to UE 305. In some other embodiments, the AMF-T 320 may transmit the next NAS message (e.g., an authentication challenge) to be sent to the UE 305, along with the current GUTI associated with the UE and the UE location (where to page the UE to send the NAS message), to the agent AMF 315-1 on the S&F satellite. In this disclosure, the agent AMF refers to AMF-NT. The UE location may also be used by the agent AMF 315-1 on the S&F satellite to determine when to page the UE (because the S&F satellite can serve many locations different from the location where the UE is to be paged during its orbit around the Earth).

[0064] Once it is determined that the UE's location can be reached, the agent AMF 315-1 on the satellite can page UE 305 using the GUTI received from the primary AMF 320. UE 305 can respond to the paging request using a service request (which is not protected by NAS security if NAS security has not yet been established) and receive DL NAS messages.

[0065] Specifically, according to embodiments of this disclosure, at point 302, UE 305 may transmit an access network (AN) message to the satellite radio access network (RAN) 310-2. The AN message may include AN parameters, a registration request (registration type, Subscription Hidden Identifier (SUCI), or 5G-GUTI or PEI). In a non-terrestrial (NG)-RAN scenario, the AN parameters may include, for example, a 5G-S-Temporary Mobile Subscriber Identity (TMSI) or a Globally Unique AMF Identifier (GUAMI), the selected Public Land Mobile Network (PLMN) ID, Network Slice Selection Assistance Information (NSSAI) information, and a reason for establishment.

[0066] The registration type can indicate whether UE 305 wants to perform initial registration, mobility registration update, periodic registration update, emergency registration, disaster roaming initial registration, or disaster roaming mobility registration update. When UE 305 is using E-UTRA, UE 305 can indicate its support for CIoT5GS optimizations related to AMF selection in the RRC connection establishment signaling associated with the registration request.

[0067] If UE 305 is sending a registration request message as an initial NAS message and UE 305 has a valid 5GNAS security context and UE 305 needs to send a non-plaintext IE, then the NAS message container will be included. If UE 305 does not need to send a non-plaintext IE, then UE 305 should send a registration request message without including the NAS message container.

[0068] In some examples, if UE 305 does not have a valid 5G NAS security context, UE 305 should send the registration request message without including the NAS message container. UE 305 should include the entire registration request message (i.e., including both plaintext and non-plaintext IEs) in a NAS message container sent as part of a secure mode completion message.

[0069] In some embodiments, when UE 305 is performing initial registration using native 5G-GUTI (i.e., the UE is in RM-DEREGISTERED state), UE 305 will indicate the relevant GUAMI information in the AN parameters. When UE is performing initial registration using its SUCI, UE should not indicate any GUAMI information in the AN parameters.

[0070] In some examples, (R)AN 310-2 can then transmit an N2 message, including N2 parameters and a registration request, to AMF-NT-1 310-1. For NR satellite access, AMF-NT-1 310-1 can verify the location of UE 305 and determine whether the PLMN targeted by UE 305 is allowed to operate at the UE's location. If AMF-NT-1 310-1 does not have connectivity to the ground (e.g., to AMF-T 320) when it receives the registration request, then AMF-NT-1 310-1 stores the registration request message.

[0071] At 304, AMF-NT-1 310-1 can transmit a new NAS message: Initial Context Establishment Request to UE 305 via (R)AN-1 310-2. In some examples, AMF-NT-1 310-1 can send a DL NAS transmission with a temporary UE identifier (temporary GUTI) to UE 305. In the context of this disclosure, it is assumed that all AMF-NTs in all satellites of the constellation will have unique AMF IDs that are distinct from each other. In one embodiment, a non-conflicting GUTI allocation is created using (GUTI = PLMN ID + AMF Region ID + AMF Set ID + AMF ID + TMSI). In some embodiments, UE 305 remembers / stores the temporary identifier (temporary GUTI) for subsequent transactions (e.g., for performing actions during the registration process). AMF-NT-1 310-1 can also provide UE 305 with the validity period of the temporary identifier.

[0072] At 306, when / if / afterwards, the satellite containing RAN-1 310-2 and AMF-NT-1 310-1 moves away from UE305 and connects to the ground station, AMF-NT-1 310-1 shall share the stored registration request message along with the temporary GUTI and UE location to the ground station's AMF-T 320.

[0073] At 308, the AMF-T 320 can decide to initiate UE authentication by calling AUSF 325. In some embodiments, the AMF-T 320 can select AUSF based on SUPI or SUCI. For example, if the AMF-T 320 can be configured to support emergency registration for unauthenticated SUPI and UE 305 indicates the registration type as emergency registration, the AMF-T 320 can skip authentication or the AMF-T 320 can accept that authentication may fail and continue the registration process.

[0074] If authentication is required, the AMF-T 320 can request authentication from the AUSF 325. At 312-1, upon / after receiving a request from the AMF-T 320, the AUSF 325 can perform authentication for the UE 305. At 312-2, the AUSF 325 can select the UDM 330 and obtain authentication data from it.

[0075] At 314, when AMF-T 325 returns the authentication data to AMF-T 320, AMF-T 320 can associate and store it with the temporary GUTI received from AMF-NT 310-1 on the satellite. AMF-T 320 can then determine the next possible satellite that can reach the UE's location.

[0076] At point 316, the AMF-T 320 can transmit the Namf_N1N2Message (containing an authentication request NAS message and a temporary GUTI) to the AMF-NT-2 315-1 on the next possible satellite. The AMF-T 320 can also provide the last known location of UE 305. At point 318, UE 305 returns after seeing a new cell (RAN-2 315-2), or the AMF-NT-2 315-1 uses the temporary GUTI and UE location to page UE 305. The UE location can also be used by the AMF-NT-2 315-1 on the S&F satellite to determine when to page the UE (because the S&F satellite can serve many locations different from the location where UE 305 is to be paged) during its orbit around the Earth. When UE 305 connects to RAN-2 315-2 or after connecting to RAN-2 315-2, RAN-2 315-2 can send an initial UE message (containing a service request). At 322, AMF-NT-2 315-1 can send an authentication request message to the UE received at 318.

[0077] At 324, UE 305 can send an authentication response message (including HXRES*) to AMF-NT-2 315-1. If AMF-NT-2 315-1 does not have ground connectivity when receiving the authentication response message, it will store the authentication response message. At 326, if AMF-T 320 receives a failure response from AMF-NT-2 315-1, AMF-T 320 will retry with other AMF-NTs.

[0078] At 328, when the AMF-NT-2 315-1 is in contact with the ground station (and moving away from the UE), it can forward the authentication response to the AMF-T 320. At 332, the AMF-T 320 can authenticate by sending an authentication request (HXRES*=XRES*) to the AUSF 325. At 334, the AUSF 325 can send an authentication response with KSEAF to the AMF-T 320.

[0079] At 336, since the NAS security context is absent, the AMF-T 320 can perform a NAS security initiation by sending a Namf_N1N2Message (containing a security mode command for the UE) and a temporary GUTI to the AMF-NT-3 335-1. The AMF-NT-3 335-1 can store this information until it reaches the coverage area of ​​the UE 305. In some embodiments, the AMF-T 320 can find a suitable AMF-NT-3 335-1 based on the criteria described at 316. The AMF-T 320 can provide the AMF-NT-3 335-1 with the last known location of the UE 305.

[0080] At 338, UE 305 returns after seeing the new cell (RAN-3 335-2), or AMF-NT-3 335-1 uses a temporary GUTI and UE location to page UE 305. The UE location can also be used by AMF-NT-2 315-1 on the S&F satellite to determine when to page the UE (because the S&F satellite can serve many locations different from the location of the UE 305 to be paged) during its orbit around the Earth. At 342, AMF-NT-3 335-1 can attempt to reach UE 305 via paging using a temporary GUTI, or UE 305 can attempt to establish an RRC connection using a service request with a temporary GUTI. AMF-NT-3 335-1 can then send a NAS security mode command to UE 305. At 344, UE 305 can enable security and acknowledge it to AMF-NT-3 335-1.

[0081] At point 346, when AMF-NT-3 335-1 receives a security mode command acknowledgment from UE 305, it can store it until ground station connectivity is re-established. Upon re-establishment of ground station connectivity, AMF-NT-3 335-1 sends the stored security mode command acknowledgment to AMF-T 320. At point 348, AMF-T 320 can determine whether to allow UE 305 to be served in the S&F scenario based on subscription information obtained from the UDM.

[0082] At 352, the AMF-T 320 can then select a suitable candidate satellite to serve the UE. The selection criteria can be as described at 316. The AMF-T 320 can send a registration acceptance message to the AMF-NT-4 350-1 via the N1N2Message transmission. The AMF-NT-4 350-1 can store the registration acceptance message. The AMF-T 320 can also provide the last known location of the UE 305.

[0083] At 354, when / after AMF-NT-4 350-1 arrives in the UE's service area, UE 305 returns after seeing the new cell (RAN-4 350-2), or AMF-NT-4 350-1 uses a temporary GUTI and UE location to page UE 305. The UE location can also be used by AMF-NT-2 315-1 on the S&F satellite to determine when to page the UE (because the S&F satellite can serve many locations different from the location where UE 305 is to be paged) during its orbit around the Earth. At 356, AMF-NT-4 350-1 can send a registration acceptance to RAN-4 350-2 and share the TMSI and AS security key. At 358, UE 305 can respond to AMF-NT-4 350-1 with registration complete. If / when there is no ground station connection, AMF-NT-4 350-1 will store the registration complete. At 360, the AMF-NT-4 350-1 can forward the registration completion until it reaches ground connection with the AMF-T 320 again.

[0084] In one embodiment, UE 305 may support storing a temporary GUTI (in response to a registration request transmission) and using the temporary GUTI to perform registration actions (e.g., in response to paging or sending any initial NAS request). The AMF-NT may be able to create different temporary GUTIs and have a different AMF pointer ID for each AMF-NT configured on the satellite. In one embodiment, the AMF-NT does not retain any security material (both AS and NAS). For each NAS message, integrity protection and encryption are performed at the AMF-T to keep the AMF-NT as lightweight as possible. It is assumed that the UE stores the temporary NAS context until the expiration time of the temporary GUTI (i.e., until the temporary GUTI expires).

[0085] Figure 4 Detailed examples of interaction 400 between a user equipment (UE), a satellite, and a ground station according to some example embodiments of this disclosure are shown. It should be noted that... Figure 4 This can be considered another example of process flow 200. For example, UE 405 can be an example device of terminal device 130, satellites 410 and 415 can be example devices of first NTN device 110, and terrestrial mobility management entity (MME-T) 420 can be an example device of TN device 120. It should be understood that these arrangements are described for illustrative purposes only and do not imply any limitation on the scope of this disclosure. The process can be implemented in the evolved packet core (EPC) network and will be described in detail below.

[0086] At 402, UE 402, camped in the E-UTRAN cell, can read the relevant system information broadcast. If UE 402 can continue to attach, it initiates the attachment process by transmitting an attachment request (IMSI or old GUTI, old GUTI type, last accessed TAI (if available)) to eNodeB 410.

[0087] The RAN-1 410-2 of the eNodeB 410 can forward the attach request message in the S1-MME control message (initial UE message). The MME-NT-1 410-1 can verify the location of UE 405 and determine whether the PLMN targeted by UE 305 is allowed to operate at the UE location.

[0088] At 404, if / when MME-NT-1 410-1 has not contacted the ground station when it receives the message in 402, MME-NT-1 410-1 may store the attach request message and generate a temporary GUTI, and send a NAS plaintext message to UE 405 requesting that the temporary GUTI be saved for subsequent NAS transactions. MME-NT-1 410-1 may also provide the validity period of the temporary GUTI. In some embodiments, UE 405 may send an acknowledgment of it.

[0089] At 406, when the MME-NT-1 410-1 regains ground connectivity, it can forward the attachment request, IMSI, and the temporary GUTI created for the request at 404 to the MME-T 420. At 408-1 and 408-2, if the UE's UE context does not exist at the MME-T 420, if the attachment request (sent in 402) is not integrity protected, or if the integrity check fails, authentication and NAS security settings are performed to activate integrity protection and NAS encryption. The MME-T 420 can obtain the authentication vector (AV) from the Home Subscriber Server (HSS) 430.

[0090] At 412-1, after obtaining the authentication key from HSS 430, MME-T 420 can attempt to find the next available satellite that can reach the UE. For this, it selects an instance of MME-NT-2 415-1, which will first be able to receive NAS requests from MME-T 420 and forward the NAS request (authentication NAS payload) to UE 405, providing the NAS request (authentication NAS payload), a temporary identifier assigned to the terminal device, and the last known location of UE 405 to the selected MME-NT-2 415-1 instance. When found, it will create an authentication NAS payload and forward it to MME-NT-2 (the next available satellite to reach the UE). MME-T 420 can also provide the last known location of UE 405.

[0091] At 412-2, when MME-NT-2 415-1 arrives at the UE area, it will page UE 405 using either the IMSI or a temporary GUTI, or both. For this purpose, the UE location received from MME-T 420 can be used by MME-NT-4 440-1 on the S&F satellite to determine when to page UE 405 (because the S&F satellite can serve many locations different from the location where UE 405 is to be paged) during its orbit around the Earth. UE 405 can also access RAN-2 415-2 when a new cell is seen. At 412-3, in both cases, when UE 405 establishes an RRC connection, MME-NT-2 415-1 can forward a stored authentication request message to UE 405. At 414, UE 405 can respond to MME-NT-2 415-1 with an authentication response, and MME-NT-2 415-1 can store it until it regains terrestrial connectivity.

[0092] At 416, if the MME-T 420 receives a failure response from the MME-NT-2 415-1, the MME-T 420 will retry with other MME-NTs. At 418, when the MME-NT-2 415-1 regains connectivity with the ground station, it can forward the stored authentication response from the UE, along with the temporary GUTI and the current UE location, to the MME-T 420. At 422, the MME-T 420 can verify the response.

[0093] At 424, if UE 405 is successfully authenticated by MME-T 420, MME-T 420 can initiate safe mode by selecting the next available satellite that can serve the UE. For this, it selects an instance of MME-NT-3 415-1, which will first be able to receive the NAS request from MME-T 420 and transmit the NAS request (safe mode command) to UE 405, and provide the NAS request (safe mode command), a temporary identifier assigned to the terminal device, and the last known location of UE 405 to the selected MME-NT-3 415-1 instance. MME-NT-3 435-1 can store the safe mode command until it reaches the UE's service area. At 426, MME-NT-3 435-1 can transmit an S10 acknowledgment to MME-T 420.

[0094] At 428-1, when MME-NT-3 435-1 arrives at the UE's service area, it can page the UE using a temporary GUTI or IMSI, or both. At 428-2, when UE 405 becomes connected, MME-NT-3 435-1 forwards the stored security mode command message to UE 405. At 432, once UE 405 applies security mode, it can acknowledge the security mode command to MME-NT-3 435-1. MME-NT-3 435-1 can store it until it regains terrestrial connectivity. At 434, when MME-NT-3 435-1 regains terrestrial connectivity, it relays the stored security mode acknowledgment message, along with the temporary identifier assigned to the terminal equipment and the last known location of UE 405, to MME-T 420.

[0095] At 436, after receiving the security mode confirmation from MME-NT-3 435-1, MME-T 420 can select Serving Gateway (SGW) 425 and assign an EPS bearer identifier to the default bearer associated with UE 405. It then sends a Session Creation Request (IMSI, MSISDN, MME TEID for Control Plane, PDN GW address, PDN address, APN) message to the selected Serving GW 425.

[0096] At 438, the serving GW 425 can create a new entry in its EPS bearer table and send a session creation request (IMSI, MSISDN, APN, user plane serving GW address, user plane serving GW TEID, control plane serving GW TEID) message to the PDN GW indicated by the previously received PDN GW address. (In this disclosure, SGW+PGW is referred to as SAE GW).

[0097] At position 442, when a session creation is received from the SAE-GW, the MME-T 420 can store the information until it finds the next available satellite to serve the UE. Once found, the MME-T 420 can send attachment acceptance and session creation response information, such as the user plane address and TEID, to the MME-NT-4 440-1. The MME-T 420 can also provide the last known location of the UE 405.

[0098] At locations 444-1 and 444-2, the MME-NT-4 440-1 can store the message until it re-enters the UE's service area. For this purpose, the UE location received from the MME-T 420 can also be used by the MME-NT-4 440-1 on the S&F satellite to determine when to page the UE (because the S&F satellite can serve many locations different from the location of the UE 405 to be paged during its orbit around the Earth). When it reaches the UE's service area, it can page UE 405 using a temporary GUTI, IMSI, or both. UE 405 can also connect automatically when it sees a new cell on a new satellite. In either case, when UE 405 enters the connected state, the MME-NT-4 440-1 can forward the message to RAN 440-2 and UE 405. RAN 440-2 will create its PDN resources based on the user plane IP and TEID information. UE 405 can receive the attachment acceptance, the new GUTI, and the PDN information.

[0099] At point 446, UE 405 can acknowledge the attachment completion by sending an attachment completion message to MME-NT-4 440-1. MME-NT-4 440-1 can store this message until it regains terrestrial connectivity. At point 448, when MME-NT-4 440-1 regains terrestrial connectivity, it can forward the stored attachment completion message to MME-T 420. Upon receiving the attachment completion message, MME-T 420 can configure the PDN connection by sending a modify bearer request to SAE-GW 425, including the RAN tunnel ID and IP information.

[0100] In the context of this disclosure, it is assumed that the UE can support storing temporary GUTIs and using them in response to paging or when sending any initial NAS request. The MME-NT is capable of creating different temporary GUTIs and has a different MME ID for each MME in the satellite. The MME-NT does not retain any security material (both AS and NAS). Integrity protection and encryption are performed at the MME-T for each NAS message. This is to keep the MME-NT as lightweight as possible.

[0101] Figure 5A flowchart of a method 500 performed by an apparatus according to some example embodiments of the present disclosure is shown. Reference will be made for discussion purposes. Figure 1A Method 500 is described from the perspective of the first NTN device 110.

[0102] At block 502, the first NTN device 110 may store / buffer the first registration request based on / in response to / if / when receiving the first registration request from the terminal device and not having connectivity with a terrestrial network (TN) device. For example, the first NTN device may determine that it has received the first registration request from the terminal device and is not connected to a TN device, and store / buffer the first registration request based on / in response to this determination. At block 504, the first NTN device may transmit an identifier assigned to the terminal device to the terminal device. Note that the transmission of the identifier may also be based on / in response to determining that it has received the first registration request from the terminal device and is not connected to a TN device.

[0103] In some embodiments, the first NTN device may transmit the validity period of the identifier assigned to the terminal device to the terminal device. In some embodiments, the first NTN device may assign the identifier to the terminal device based on the identifier of the first NTN device.

[0104] In some embodiments, the first NTN device may receive the location information of the terminal device from the terminal device or from a radio network entity (e.g., BS) serving the terminal device.

[0105] In some embodiments, when / if / based on / in response to having connectivity with or being connected to a TN device, the first NTN device may transmit a first registration request and an identifier assigned to the terminal device to the TN device. For example, the first NTN device may determine that it has connectivity with or is connected to a TN device, and based on / in response to this determination, transmit a stored / buffered first registration request and an identifier assigned to the terminal device to the TN device. In some embodiments, the first NTN device may transmit the location information of the terminal device, along with the first registration request and the identifier assigned to the terminal device (based on / in response to determining that it has connectivity with or is connected to a TN device), to the TN device.

[0106] In some embodiments, the first NTN device may receive a NAS request targeted at a terminal device and an identifier assigned to the terminal device from the TN device. In some embodiments, the first NTN device receiving the NAS request from the TN device may be different from the first NTN device that transmits the registration request and the identifier assigned to the terminal device (e.g., AMF-NT-1 and AMF-NT-2).

[0107] In some embodiments, the first NTN device can connect to the terminal device using the terminal device's identifier; transmit a NAS request targeting the terminal device to the terminal device; and receive a NAS response from the terminal device.

[0108] In some embodiments, the first NTN device can connect to the terminal device by paging the terminal device using the terminal device's identifier. In some embodiments, the first NTN device can connect to the terminal device by paging the terminal device using the terminal device's identifier and the terminal device's location.

[0109] In some embodiments, when there is no connectivity with a TN device, the first NTN device may store NAS responses; and in some embodiments, when there is connectivity with a TN device, the first NTN device may transmit NAS responses to the TN device. In some embodiments, the NTN device corresponds to an instance of an NTN device different from those described above.

[0110] In some embodiments, the first NTN device may receive an authentication request, a security mode command for the terminal device, and an identifier assigned to the terminal device from the TN device. In some embodiments, the first NTN device may be an AMF-NT; and in some embodiments, the TN device is a terrestrial AMF.

[0111] In some embodiments, the first NTN device is a non-terrestrial mobility management entity (MME); and in some embodiments, the TN device is a terrestrial MME.

[0112] Figure 6 A flowchart of a method 600 performed by an apparatus according to some example embodiments of the present disclosure is shown. Reference will be made to this flowchart for discussion purposes. Figure 1A Method 600 is described from the perspective of TN equipment 120.

[0113] At box 602, TN device 120 may receive an identifier assigned to a terminal device and a first registration request (for that terminal device / for that terminal device) from a first non-terrestrial network (NTN) device. At box 604, TN device 120 may use the identifier assigned to the terminal device to initiate authentication for the terminal device.

[0114] In some embodiments, the TN device 120 may initiate authentication for a terminal device by: selecting a third network device based on a subscription permanent identifier (SUPI or IMSI) or a subscription hidden identifier (SUCI); receiving authentication data from the third network device; and storing the authentication data in correspondence with the identifier assigned to the terminal device. In some embodiments, the TN device 120 may receive the location information of the terminal device from a first NTN device along with a first registration request and the identifier assigned to the terminal device.

[0115] In some embodiments, TN device 120 may transmit a NAS request targeting a terminal device and an identifier assigned to the terminal device to a second NTN device. In some other embodiments, TN device 120 may transmit a NAS request targeting a terminal device, an identifier assigned to the terminal device, and location information associated with the device to the second NTN device. In some embodiments, TN device 120 may receive a NAS response from the second NTN device. In some other examples, the first NTN device and the second NTN device may be non-terrestrial access and mobility management functions (AMF-NT), and the TN device may be a terrestrial AMF. In some other examples, the first NTN device may be a non-terrestrial mobility management entity (MME), and the TN device may be a terrestrial MME.

[0116] It should be noted that TN device 120 can identify the next NTN device (or the device on which the NTN device is configured) capable of contacting the terminal device as the second NTN device. In some embodiments, the first NTN device and the second NTN device may be configured on the same NTN device. For example, the first NTN device and the second NTN device may be configured on the same satellite. In some embodiments, the first NTN device and the second NTN device are different NTN devices (e.g., AMF-NT-1 and AMF-NT-2) (e.g., MME-NT-1 and MME-NT-2).

[0117] Figure 7 A flowchart of a method 700 performed by an apparatus according to some example embodiments of the present disclosure is shown. Reference will be made to this flowchart for discussion purposes. Figure 1A Method 700 is described from the perspective of terminal device 130.

[0118] At block 702, terminal device 130 may transmit a first registration request to a first non-terrestrial network (NTN) device. At block 704, terminal device 130 may receive an identifier assigned to terminal device 130 in response to the first NTN device in response to the first registration request.

[0119] In some embodiments, the terminal device may receive the validity period of the identifier assigned to the terminal device from the first NTN device.

[0120] In one embodiment, terminal device 130 performs subsequent registration procedures / actions using an identifier received in response to a first registration request. For example, terminal device 130 may use an identifier assigned to the terminal device to connect to a second NTN device. Alternatively or otherwise, terminal device 130 may be paged by the second NTN device using the identifier assigned to the terminal device to perform subsequent registration procedures / actions.

[0121] In some embodiments, the terminal device can connect to the second NTN device using its own identifier (e.g., the second NTN device can page the terminal device using an identifier assigned to the terminal device in response to a first registration request). The terminal device can receive NAS requests targeted at the terminal device from the second NTN device. The terminal device can transmit NAS responses to the second NTN device.

[0122] In some embodiments, the first NTN device and the second NTN device may be configured on the same NTN device. For example, the first NTN device and the second NTN device may be configured on the same satellite. In some embodiments, the first NTN device and the second NTN device are different NTN devices (e.g., AMF-NT-1 and AMF-NT-2).

[0123] In some embodiments, the means capable of performing any of the methods 500 may be part of the first NTN device 110 and may include components for performing the corresponding operations of method 500. The components may be implemented in any suitable form. For example, the components may be implemented in a circuit or software module.

[0124] In some embodiments, the apparatus includes components for storing a first registration request based on receiving a first registration request from a terminal device and not having connectivity with a terrestrial network (TN) device. In some embodiments, the apparatus includes components for transmitting an identifier assigned to the terminal device to the terminal device.

[0125] In some embodiments, the apparatus includes components for transmitting the validity period of an identifier assigned to the terminal device to the terminal device. In some embodiments, the apparatus includes components for assigning an identifier to the terminal device based on an identifier of a first NTN device.

[0126] In some embodiments, the apparatus includes components for transmitting a first registration request and an identifier assigned to a terminal device to the TN device when connectivity with the TN device is available. In some embodiments, the apparatus includes components for transmitting location information of the terminal device along with the first registration request and the identifier assigned to the terminal device to the TN device.

[0127] In some embodiments, the apparatus includes components for receiving a Non-Access Stratum (NAS) request targeting a terminal device and an identifier assigned to the terminal device from a TN device.

[0128] In some embodiments, the apparatus includes components for connecting to a terminal device using an identifier of the terminal device; transmitting a NAS request targeting the terminal device to the terminal device; and receiving a NAS response from the terminal device.

[0129] In some embodiments, the apparatus includes components for connecting to a terminal device by paging the terminal device using the terminal device's identifier. In some embodiments, the apparatus includes components for connecting to a terminal device by paging the terminal device using the terminal device's identifier and the terminal device's location.

[0130] In some embodiments, the apparatus includes components for storing NAS responses when there is no connectivity with a TN device; and in some embodiments, when there is connectivity with a TN device, the first NTN device can transmit the NAS response to the TN device. In some embodiments, the apparatus includes components for the NTN device to correspond to an NTN device instance different from the one described above.

[0131] In some embodiments, the apparatus includes components for a first NTN device to be a non-terrestrial access and mobility management function (AMF-NT); and in some embodiments, the apparatus includes components for a TN device to be a terrestrial AMF.

[0132] In some embodiments, the apparatus includes components for the first NTN device to be a non-terrestrial mobility management entity (MME); and in some embodiments, the TN device is a terrestrial MME.

[0133] In some embodiments, the apparatus further includes components for performing other steps in some embodiments of method 500. In some embodiments, the apparatus includes at least one processor and at least one memory including computer program code, the at least one memory and the computer program code being configured to cause the apparatus to execute together with the at least one processor.

[0134] In some embodiments, the means capable of performing any of the methods 600 may be part of the TN device 120 and may include components for performing the corresponding operations of method 600. The components may be implemented in any suitable form. For example, the components may be implemented in a circuit or software module.

[0135] In some embodiments, the apparatus includes components for receiving an identifier assigned to a terminal device and a first registration request from a first non-terrestrial network (NTN) device. In some embodiments, the apparatus includes components for initiating authentication for the terminal device using the identifier assigned to the terminal device.

[0136] In some embodiments, the apparatus includes components for initiating authentication for a terminal device by selecting a third network device based on a subscription permanent identifier (SUPI or IMSI) or a subscription hidden identifier (SUCI); components for receiving authentication data from the third network device; and components for storing the authentication data in correspondence with the identifier assigned to the terminal device.

[0137] In some embodiments, the apparatus includes components for receiving location information of a terminal device along with a first registration request and an identifier assigned to the terminal device from a first NTN device.

[0138] In some embodiments, the apparatus includes components for transmitting a NAS request targeting a terminal device and an identifier assigned to the terminal device to a second NTN device. In some embodiments, the apparatus includes components for transmitting a NAS request targeting a terminal device, an identifier assigned to the terminal device, and location information associated with the device to the second NTN device. In some embodiments, the apparatus includes components for receiving a NAS response from the second NTN device.

[0139] In some embodiments, the apparatus includes components for a first NTN device being a non-terrestrial access and mobility management function (AMF-NT) and a TN device being a terrestrial AMF. In some embodiments, the apparatus includes components for a first NTN device being a non-terrestrial mobility management entity (MME) and a TN device being a terrestrial MME.

[0140] In some embodiments, the apparatus further includes components for performing other steps in some embodiments of method 600. In some embodiments, the apparatus includes at least one processor and at least one memory including computer program code, the at least one memory and the computer program code being configured to cause the apparatus to execute together with the at least one processor.

[0141] In some embodiments, the means capable of performing any of the methods 700 may be part of the terminal device 130 and may include components for performing the corresponding operations of method 700. The components may be implemented in any suitable form. For example, the components may be implemented in a circuit or software module.

[0142] In some embodiments, the apparatus further includes components for transmitting a first registration request to a first non-terrestrial network (NTN) device. In some embodiments, the apparatus further includes components for receiving an identifier assigned to a terminal device in response to the first NTN device.

[0143] In some embodiments, the apparatus further includes components for receiving, from a first NTN device, the validity period of an identifier assigned to a terminal device. In some embodiments, the apparatus further includes: components for connecting to a second NTN device using the identifier of the terminal device; components for receiving, from the second NTN device, a NAS request targeting the terminal device; and components for transmitting a NAS response to the second NTN device.

[0144] In some embodiments, the apparatus further includes components for performing other steps in some embodiments of method 700. In some embodiments, the apparatus includes at least one processor and at least one memory including computer program code, the at least one memory and the computer program code being configured to cause the apparatus to execute together with the at least one processor.

[0145] Figure 8 A simplified block diagram of a device 800 suitable for implementing some example embodiments of the present disclosure is shown. The device 800 can be provided to implement communication devices, such as terminal device 130 and network devices 110, 120 as shown in FIG1. ​​As shown, the device 800 includes one or more processors 810, one or more memories 820 coupled to the processors 810, and one or more communication modules 840 coupled to the processors 810.

[0146] Communication module 840 is used for bidirectional communication. Communication module 840 has at least one antenna to facilitate communication. The communication interface can represent any interface required for communication with other network elements.

[0147] As a non-limiting example, processor 810 can be any type suitable for a local technology network and can include one or more of the following: general-purpose computer, special-purpose computer, microprocessor, digital signal processor (DSP), and processor based on a multi-core processor architecture. Device 800 can have multiple processors, such as application-specific integrated circuit chips that are time-dependent on a clock synchronized with a main processor.

[0148] Memory 820 may include one or more non-volatile memories and one or more volatile memories. Examples of non-volatile memories include, but are not limited to, read-only memory (ROM) 824, electrically programmable read-only memory (EPROM), flash memory, hard disk, optical disc (CD), digital video disc (DVD), and other magnetic and / or optical storage. Examples of volatile memories include, but are not limited to, random access memory (RAM) 822 and other volatile memories that cannot retain data during power loss.

[0149] Computer program 830 includes computer-executable instructions that are executed by the associated processor 810. Program 830 may be stored in ROM 824. Processor 810 may perform any suitable actions and processes by loading program 830 into RAM 822.

[0150] The embodiments of this disclosure can be implemented via program 830, enabling device 800 to perform as described in the reference. Figures 2 to 6 Any process discussed in this disclosure. Embodiments of this disclosure may also be implemented by hardware or by a combination of software and hardware.

[0151] In some example embodiments, program 830 may be tangibly contained in a computer-readable medium, which may be included in device 800 (such as memory 820) or other storage device accessible by device 800. Device 800 may load program 830 from the computer-readable medium into RAM 822 for execution. The computer-readable medium may include any type of tangible non-volatile memory, such as ROM, EPROM, flash memory, hard disk, CD, DVD, etc.

[0152] Figure 9 A block diagram of an example of a computer-readable medium 900 according to some exemplary embodiments of the present disclosure is shown. A program 930 is stored on the computer-readable medium 900. Note that although in Figure 9 The computer-readable medium 900 is depicted in the form of a CD or DVD, but the computer-readable medium 900 may be any other form suitable for carrying or storing the program 930.

[0153] Generally, the various embodiments of this disclosure can be implemented in hardware or dedicated circuitry, software, logic, or any combination thereof. Some aspects can be implemented in hardware, while others can be implemented in firmware or software that can be executed by a controller, microprocessor, or other computing device. Although various aspects of the embodiments of this disclosure are illustrated and described as block diagrams, flowcharts, or using some other graphical representation, it should be understood that, as non-limiting examples, the blocks, apparatuses, systems, techniques, or methods described herein can be implemented in hardware, software, firmware, dedicated circuitry or logic, general-purpose hardware or controllers or other computing devices, or some combination thereof.

[0154] This disclosure also provides at least one computer program product tangibly stored on a non-transitory computer-readable storage medium. The computer program product includes computer-executable instructions that execute in a device on a target real or virtual processor, such as those included in a program module, to perform the above-referenced... Figure 5 Alternatively, the method described in 6, 500 or 600, may be used. Typically, a program module includes routines, programs, libraries, objects, classes, components, data structures, etc., that perform specific tasks or implement specific abstract data types. In various embodiments, the functionality of a program module can be combined or split among program modules as needed. The machine-executable instructions used in a program module can be executed locally or in a distributed device. In a distributed device, the program module can reside in both local and remote storage media.

[0155] Program code used to perform the methods of this disclosure may be written in any combination of one or more programming languages. This program code may be provided to a processor or controller of a general-purpose computer, special-purpose computer, or other programmable data processing apparatus, such that when executed by the processor or controller, the program code causes the functions / operations specified in the flowcharts and / or block diagrams to be implemented. The program code may be executed entirely on a machine, partially on a machine, as a stand-alone software package, partially on a machine and partially on a remote machine, or entirely on a remote machine or server.

[0156] In the context of this disclosure, computer program code or related data may be carried by any suitable carrier to enable a device, apparatus, or processor to perform the various processes and operations described above. Examples of carriers include signals, computer-readable media, etc.

[0157] Computer-readable media can be computer-readable signal media or computer-readable storage media. Computer-readable media can include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatuses, or devices, or any suitable combination thereof. More specific examples of computer-readable storage media will include electrical connections having one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable optical disc read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof. As used herein, the term “non-transient” is a limitation on the medium itself (i.e., tangible, not signaling), not a limitation on the persistence of data storage (e.g., RAM and ROM).

[0158] Furthermore, although the operations are described in a specific order, this should not be construed as requiring that these operations be performed in the specific order shown or sequentially, or that all the operations shown be performed to achieve the desired result. In some cases, multitasking and parallel processing may be advantageous. Similarly, while several specific embodiment details are contained in the foregoing discussion, these details should not be construed as limiting the scope of this disclosure, but rather as descriptions of features that may be specific to particular embodiments. Certain features described in the context of individual embodiments may also be implemented in combination in a single embodiment. Conversely, various features described in the context of a single embodiment may also be implemented individually or in any suitable sub-combination in multiple embodiments.

[0159] Although this disclosure has been described in language specific to structural features and / or methodological actions, it should be understood that the disclosure as defined in the appended claims is not necessarily limited to the specific features or actions described above. Rather, the specific features and actions described above are disclosed as exemplary forms for implementing the claims.

Claims

1. A first non-terrestrial network (NTN) device, comprising: At least one processor; as well as At least one memory storing instructions that, when executed by the at least one processor, cause the first NTN device to at least: Based on receiving a first registration request from a terminal device and not having connectivity with a terrestrial network (TN) device, the first registration request is stored; as well as Transmit the identifier assigned to the terminal device to the terminal device.

2. The first NTN device according to claim 1, wherein the first NTN device is further configured to: The validity period of the identifier assigned to the terminal device is transmitted to the terminal device.

3. The first NTN device according to claim 1, wherein the first NTN device is further configured to: The identifier is assigned to the terminal device based on the identifier of the first NTN device.

4. The first NTN device according to any one of claims 1-3, wherein the first NTN device is further configured to: When the connectivity with the TN device is established, the first registration request and the identifier assigned to the terminal device are transmitted to the TN device.

5. The first NTN device according to any one of claims 1-4, wherein the first NTN device is further configured to: The location information of the terminal device, along with the first registration request and the identifier assigned to the terminal device, are transmitted to the TN device.

6. The first NTN device according to any one of claims 1-5, wherein the first NTN device is further configured to: The TN device receives a Non-Access Stratum (NAS) request targeting the terminal device and the identifier assigned to the terminal device.

7. The first NTN device according to claim 5, wherein the first NTN device is further configured to: Connect to the terminal device by using the identifier of the terminal device; Transmit the NAS request targeting the terminal device to the terminal device; as well as Receive NAS response from the terminal device.

8. The first NTN device according to claim 7, wherein the first NTN device is further configured to: Connect to the terminal device by paging the terminal device using the identifier of the terminal device.

9. The first NTN device according to claim 7, wherein the first NTN device is further configured to: The terminal device is connected by paging the terminal device using the identifier and the location of the terminal device.

10. The first NTN device according to claim 7, wherein the first NTN device is further configured to: When there is no connectivity to the TN device, store the NAS response; and When the connectivity with the TN device is established, the NAS response is transmitted to the TN device.

11. The first NTN device according to any one of claims 1-10, wherein the first NTN device is a non-terrestrial access and mobility management function (AMF-NT); and The TN device is a ground-based AMF.

12. The first NTN device according to any one of claims 1-10, wherein the first NTN device is a non-terrestrial mobility management entity (MME); and The TN equipment is a ground-based MME.

13. A terrestrial network (TN) device, comprising: At least one processor; as well as At least one memory storing instructions that, when executed by the at least one processor, cause the TN device to at least: Receive the identifier and first registration request assigned to the terminal device from the first non-terrestrial network (NTN) device; as well as The identifier assigned to the terminal device is used to initiate authentication for the terminal device.

14. The TN device of claim 13, wherein the TN device is further configured to initiate the authentication for the terminal device by: Select a third network device based on a subscription permanent identifier (SUPI or IMSI) or a subscription hidden identifier (SUCI); Receive authentication data from the third network device; as well as The authentication data is stored in correspondence with the identifier assigned to the terminal device.

15. The TN device according to claim 13 or 14, wherein the TN device is further configured to: The location information of the terminal device is received from the first NTN device along with the first registration request and the identifier assigned to the terminal device.

16. The TN device according to any one of claims 13-15, wherein the TN device is further configured to: The NAS request targeting the terminal device and the identifier assigned to the terminal device are transmitted to the second NTN device.

17. The TN device according to any one of claims 13-16, wherein the TN device is further configured such that: The NAS request targeting the terminal device and the identifier assigned to the terminal device, along with the location information associated with the device, are transmitted to the second NTN device.

18. The TN device of claim 16, wherein the TN device is further configured to: Receive NAS response from the second NTN device.

19. The TN equipment according to any one of claims 13-18, wherein the first NTN equipment is a non-terrestrial access and mobility management function (AMF-NT); and The TN device is a ground-based AMF.

20. The TN device according to any one of claims 13-18, wherein the first NTN device is a non-terrestrial mobility management entity (MME); and The TN equipment is a ground-based MME.

21. A terminal device, comprising: At least one processor; as well as At least one memory storing instructions that, when executed by the at least one processor, cause the terminal to at least: Transmit the first registration request to the first non-terrestrial network (NTN) device; as well as Receive from the first NTN device the identifier assigned to the terminal device in response to the first registration request.

22. The terminal device according to claim 21, wherein the terminal device is further configured to: Receive the validity period of the identifier assigned to the terminal device from the first NTN device.

23. The terminal device according to claim 21 or 22, wherein the terminal device is further configured to: Connect to the second NTN device by using the identifier of the terminal device; Receive a NAS request targeting the terminal device from the second NTN device; and Transmit the NAS response to the second NTN device.

24. A method comprising: Based on receiving a first registration request from a terminal device and not having connectivity with a terrestrial network (TN) device, the first registration request is stored; as well as Transmit the identifier assigned to the terminal device to the terminal device.

25. A method comprising: Receive the identifier assigned to the terminal device and the first registration request from the first NTN device; as well as The identifier assigned to the terminal device is used to initiate authentication for the terminal device.

26. A method comprising: Transmit the first registration request to the first NTN device; as well as Receive from the first NTN device the identifier assigned to the terminal device in response to the first registration request.

Images