Methods, apparatuses and computer programs

Abstract

A method, apparatus, and computer program are provided for causing an apparatus to perform: receiving, from an access and mobility management function of a visited core network via a first access network node of a first network, an identification of at least one radio access technology not supported by a home core network; and using the received identification for selecting an access network node for connecting to at least one of: the visited core network or the home core network.

Description

Technical Field

[0001] This application relates to an operation for inducing an identification associated with signaling notification of at least one radio access technology not supported by the core network. Background Technology

[0002] A communication system can be viewed as a facility that enables a communication session between two or more entities (such as user terminals, base stations, and / or other nodes) by providing a carrier wave between the various entities involved in the communication session. A communication system can be provided, for example, through a communication network and one or more compatible communication devices. A communication session can include, for example, data communication for carrying communications such as voice, video, email, SMS, multimedia, and / or content data. Non-limiting examples of the services provided include two-way or multi-way calling, data communication or multimedia services, and access to data network systems such as the Internet.

[0003] Communication systems and associated equipment typically operate according to a given standard or specification that defines what the various entities associated with the system are allowed to do and how this should be implemented. The communication protocols and / or parameters that should be used for connectivity are also usually defined. An example of a communication system is UTRAN (Universal Mobile Telecommunications Services Terrestrial Radio Access Network, e.g., 3G Radio). Other examples of communication systems are the Long Term Evolution (LTE) of Universal Mobile Telecommunications System (UMTS) radio access technology and so-called 5G or New Radio (NR) networks. NR is being standardized by the 3rd Generation Partnership Project (3GPP). Summary of the Invention

[0004] According to a first aspect, an apparatus for a user equipment is provided, the apparatus comprising components for performing: receiving, via a first access network node of a first network, an identifier of at least one radio access technology not supported by a home core network from an access and mobility management function of a visited core network; and using the received identifier to select an access network node for connecting to at least one of: a visited core network or a home core network.

[0005] According to a second aspect, an apparatus for a user equipment is provided, the apparatus comprising: at least one processor; and at least one memory including code that, when executed by the at least one processor, causes the apparatus to perform: receiving, via a first access network node of a first network, an identifier of at least one radio access technology not supported by a home core network from an access and mobility management function of a visited core network; and using the received identifier to select an access network node for connection to at least one of: a visited core network or a home network.

[0006] According to a third aspect, a method for an apparatus for a user equipment is provided, the method comprising: receiving, via a first access network node of a first network, an identifier of at least one radio access technology not supported by a home core network from an access and mobility management function of a visited core network; and using the received identifier to select an access network node for connecting to at least one of: a visited core network or a home core network.

[0007] According to a fourth aspect, an apparatus for a user equipment is provided, the apparatus comprising: a receiving circuitry system for receiving, via a first access network node of a first network, an identifier of at least one radio access technology not supported by a home core network from an access and mobility management function of a visited core network; and a using circuitry system for using the received identifier to select an access network node for connection to at least one of: a visited core network or a home network.

[0008] The following can be applied to any (e.g., all) of the first to fourth aspects mentioned above.

[0009] The receiving identifier may include: a message receiving identifier received via registration.

[0010] Using the received identifier to select an access network node for connection to the core network may include: determining that the first network is not using at least one of the identified radio access technologies to provide connectivity services to the visited core access network; and maintaining the connection to the visited core network via the first access network node.

[0011] Using the received identifier to select an access network node for connection to the core network may include: determining that a first network is using at least one radio access technology identified to provide connectivity services to the visited core access network; and switching from the first access network node to the visited core access network via a second access network node, wherein the first access network node and the second access network node are different access network nodes.

[0012] The device can also be configured to: select a second access network node for receiving core network access based on a determination that the second access network node is operating according to a radio access technology not identified in the identifier received from the access and mobility management functions.

[0013] The handover may include: releasing the radio resource connection with the first access network node; and establishing a radio resource connection with the second access network node.

[0014] The device can also be made to: receive an instruction from a third access network node to connect to the core network via the third access network node; and determine, based on the received identifier and the determined radio access technology provided by the third access network node, whether to connect to the core network via the third network node.

[0015] According to a fifth aspect, an apparatus is provided for a unified data management function for a home core network function, the apparatus including components for performing the following: sending an identifier of at least one radio access technology not supported by the home core network to a user equipment via an access and mobility management function of the visited core network.

[0016] According to a sixth aspect, an apparatus is provided for a unified data management function for a home core network function, the apparatus comprising: at least one processor; and at least one memory including code that, when executed by the at least one processor, causes the apparatus to perform: sending an identifier of at least one radio access technology not supported by the home core network to a user equipment via an access and mobility management function of the visited core network.

[0017] According to a seventh aspect, a method is provided for an apparatus for a unified data management function for a home core network function, the method comprising: sending to a user equipment an identifier of at least one radio access technology not supported by the home core network via an access and mobility management function of the visited core network.

[0018] According to the eighth aspect, an apparatus for a unified data management function for a home core network function is provided, the apparatus comprising: a transmitting circuit system for transmitting, via access and mobility management functions of a visited core network, an identifier of at least one radio access technology not supported by the home core network to a user equipment.

[0019] The following can be applied to any (e.g., all) of the above aspects five through eight.

[0020] Sending the identifier may include sending the identifier via signaling that is protected for confidentiality and integrity by the access network node.

[0021] The sending identifier may include: a sending identifier via non-access stratum signaling.

[0022] According to a ninth aspect, an apparatus is provided for access and mobility functions of a visited core network, the apparatus comprising components for performing: receiving from a unified data management system of the home core network an identifier of at least one radio access technology not supported by the home core network; and transmitting the received identifier to a user equipment via a first access network node.

[0023] According to a tenth aspect, an apparatus for access and mobility functions of a visited core network is provided, the apparatus comprising: at least one processor; and at least one memory including code that, when executed by the at least one processor, causes the apparatus to perform: receiving an identifier of at least one radio access technology not supported by the home core network from a unified data management system of the home core network; and transmitting the received identifier to a user equipment via a first access network node.

[0024] According to the eleventh aspect, a method is provided for an apparatus for access and mobility functions for a visited core network, the method comprising: receiving from a unified data management system of a home core network an identifier of at least one radio access technology not supported by the home core network; and transmitting the received identifier to a user equipment via a first access network node.

[0025] According to the twelfth aspect, an apparatus for access and mobility functions of a visited core network is provided, the apparatus comprising: a receiving circuit system for receiving from a unified data management system of the home core network an identifier of at least one radio access technology not supported by the home core network; and a transmitting circuit system for transmitting the received identifier to a user equipment via a first access network node.

[0026] The following can be applied to any (e.g., all) of the first to twelfth aspects mentioned above.

[0027] The received identifier can be included in the registration response message.

[0028] The received identifier may be included in the signaling for the roaming service operation and / or in the signaling for the user parameter update service operation.

[0029] The identified wireless access technology may include at least one of the following: 2G, 3G, 4G and / or 5G.

[0030] The identifier of at least one radio access technology not supported by the home core network can identify at least one radio access technology with a security mechanism that does not comply with the security mechanism of the home core network.

[0031] According to a thirteenth aspect, an apparatus for a user equipment is provided, the apparatus comprising components for performing: receiving, via a first access network node of a first network, an identifier of at least one radio access technology not supported by the core network from a core network function of a core network; and using the received identifier to select an access network node for connecting to the core network.

[0032] According to the fourteenth aspect, an apparatus for a user equipment is provided, the apparatus comprising: at least one processor; and at least one memory including code that, when executed by the at least one processor, causes the apparatus to perform: receiving, via a first access network node of a first network, an identifier of at least one radio access technology not supported by the core network from a core network function of a core network; and using the received identifier to select an access network node for connecting to the core network.

[0033] According to the fifteenth aspect, a method for an apparatus for a user equipment is provided, the method comprising: receiving, via a first access network node of a first network, an identifier of at least one radio access technology not supported by the core network from a core network function of a core network; and using the received identifier to select an access network node for connecting to the core network.

[0034] According to a sixteenth aspect, an apparatus for a user equipment is provided, the apparatus comprising: a receiving circuitry system for receiving, via a first access network node of a first network, an identifier of at least one radio access technology not supported by the core network from a core network function of a core network; and a using circuitry system for using the received identifier to select an access network node for connecting to the core network.

[0035] The following can be applied to any (e.g., all) of the above-mentioned aspects thirteen through sixteen.

[0036] The receiving identifier may include a signaling receiving identifier protected by the first access network node for confidentiality and integrity.

[0037] The receive identifier may include: a receive identifier via non-access stratum signaling.

[0038] Using the received information to select an access network node for connection to the core network may include: determining at least one radio access technology identified by the first network that provides connectivity services to the core access network; and maintaining the connection to the core network via the first access network node.

[0039] Using the received identifier to select an access network node for connecting to the core network may include: determining that a first network is using at least one radio access technology identified to provide connectivity services to the core access network; and switching from the first access network node to a second access network node for connecting to the core network, wherein the first access network node and the second access network node are different access network nodes.

[0040] The device can also be configured to perform: selecting a second access network node for connection to the core network based on a determination that the second access network node is operating according to a radio access technology not identified in the identifier received from the core network function.

[0041] The handover may include: releasing the radio resource connection with the first access network node; and establishing a radio resource connection with the second access network node.

[0042] The device can also be made to: receive an instruction from a third access network node to connect to the core network via the third access network node; and determine, based on the received identifier and the determined radio access technology provided by the third access network node, whether to connect to the core network via the third access network node.

[0043] The device can also be made to: determine a switch from the current access network node to another access network node for connection to the core network; and select another network node using the received identifier.

[0044] According to the seventeenth aspect, an apparatus for core network functions is provided, the apparatus including components for performing the following: transmitting, via a first access network node, an identifier of at least one radio access technology not supported by the core network to a user equipment.

[0045] According to the eighteenth aspect, an apparatus for core network functions is provided, the apparatus comprising: at least one processor; and at least one memory including code that, when executed by the at least one processor, causes the apparatus to perform: sending an identifier of at least one radio access technology not supported by the core network to a user equipment via a first access network node.

[0046] According to the nineteenth aspect, a method for an apparatus for core network functions is provided, the method comprising: sending an identifier of at least one radio access technology not supported by the core network to a user equipment via a first access network node.

[0047] According to the twentieth aspect, an apparatus for core network functions is provided, the apparatus comprising: a transmitting circuit system for transmitting, via a first access network node, an identifier of at least one radio access technology not supported by the core network to a user equipment.

[0048] The following can be applied to any (e.g., all) of the seventeenth to twentieth aspects mentioned above.

[0049] The transmission identifier may include a signaling transmission identifier protected by the first access network node for confidentiality and integrity.

[0050] The sending identifier may include: a sending identifier via non-access stratum signaling.

[0051] The following can be applied to any (e.g., all) of the above-mentioned aspects thirteen through twentieth.

[0052] The identifier can be included in the registration response message.

[0053] The identifier may be included in the signaling for the initiation of the roaming service operation and / or in the signaling for the user parameter update service operation.

[0054] The identified wireless access technology may include at least one of the following: 2G, 3G, 4G and / or 5G.

[0055] The identifier of at least one radio access technology not supported by the core network can identify at least one radio access technology with a security mechanism that does not comply with the security mechanism of the core network.

[0056] Core network functions may include at least one of the following: home public land mobile network or visited public land mobile network.

[0057] According to one aspect, a non-transitory computer-readable medium is provided, comprising program instructions that, when executed by a means, cause the means to perform at least the method according to any of the foregoing aspects.

[0058] In the foregoing, many different embodiments have been described. It should be understood that further embodiments may be provided by combination of any two or more of the embodiments described above. Attached Figure Description

[0059] The embodiments will now be described by way of example only with reference to the accompanying drawings, in which:

[0060] Figures 1A to 1B Representations of a network system according to some example embodiments are shown;

[0061] Figure 2 A representation of a control device according to some example embodiments is shown;

[0062] Figure 3 A representation of an apparatus according to some example embodiments is shown;

[0063] Figures 4 to 5 The example signaling is illustrated;

[0064] Figure 6 The illustration shows example information fields; and

[0065] Figures 7 to 11 Example operations that can be performed by the apparatus described herein are illustrated. Detailed Implementation

[0066] The following describes operations that can be performed to help maintain a minimum level of security for a user equipment (UE) communicating via a cell and network operating according to a radio access technology (e.g., 2G, 3G, 4G, 5G, 6G, etc.) provided by an access network node.

[0067] More specifically, 3GPP Rel-15 introduces an assumption that the Public Land Mobile Network (PLMN) 5G Radio Access Technology (RAT) will not coexist with the 2G RAT, and that the 5G PLMN RAT will be integrated with the 3G RAT for limited use cases (e.g., the 5G PLMN can support the 3G RAT for, for example, voice calls, such as single radio voice calls).

[0068] However, the assumption that 2G RAT and / or some 3G RAT will not coexist with 5G is not always true in reality, as 2G RAT and / or 3G RAT do indeed coexist with 5G PLMN in many networks. The coexistence of 2G RAT and / or 3G RAT is not explicitly prohibited in the 3GPP standard, which has led to changes in the area where cells of different RAT types are connected to the same core network operated by the network operator.

[0069] While coexistence is possible, some network operators have taken steps to “disable” access network nodes from these older RATs (e.g., 2G, 3G), allowing 5G PLMN operators to provide services using newer radio access technologies. In other words, some network operators have introduced restrictions and / or bans to prohibit the use of older RATs to provide connectivity services to the network. This can help network operators maintain a minimum level of security for signaling information between user equipment and the network via access network nodes.

[0070] Given this disabling, allowing UEs supporting 2G or 3G RAT networks to continue selecting such networks for connecting to the 5G core is no longer applicable. Furthermore, due to the weaker security mechanisms in these previous-generation technologies, UEs would be vulnerable to many known 2G and 3G-related attacks if tricked into selecting such networks.

[0071] To address at least one of the aforementioned problems, a mechanism is described below for enabling core network functions to identify at least one radio access technology (RAT) not supported by the core network to user equipment connected to the core network via access network nodes. For example, a network operator may have defined at least one RAT as not meeting the minimum security level to be applied by the core network.

[0072] User equipment can be provided with at least one RAT(s) identifier using signaling protected by access network nodes for confidentiality (e.g., unreadable and / or encrypted) and / or integrity (e.g., unmodifiable). This can be performed, for example, using non-access stratum signaling. The examples provided below illustrate such non-access stratum signaling using procedures such as bootstrapping and user parameter update service operations. However, it should be understood that the techniques described herein are not limited to signaling for these two service operations.

[0073] User Equipment (UE) can use the identifier of at least one RAT to determine whether it should switch from the access network node it is currently using to connect to the core network to another access network node. In other words, UE can determine whether the access network node is using a RAT corresponding to the identified at least one RAT. When the access network node is using a RAT corresponding to the identified at least one RAT, UE can disconnect from the access node (e.g., release the Radio Resource Control (RRC) connection with that access node). UE can also select another access network node based on the identified at least one RAT, such that the other access network node does not deploy at least one RAT. When the access network node is not using a RAT corresponding to the identified at least one RAT, UE can maintain the connection to the core network via the access network node (e.g., maintain the RRC connection).

[0074] In both cases (e.g., maintaining a Radio Resource Control (RRC) connection and releasing a RRC connection), the user equipment may also maintain (e.g., store) at least one RAT(s) identifier(s) and use the maintained identifier(s)(s) to perform cell selection during a later mobility process.

[0075] Some examples of how this can be implemented are provided below in the reference to 5G terminology.

[0076] In addition, although the aforementioned disabling scenarios are discussed in terms of disabling 2G and 3G RAT networks used to provide connectivity services to 5GC, the same principle applies to any "older" RAT networks disabled by newer PLMN operators. For example, when a newer PLMN operator includes a 6G network operator, the disabled "older" RAT network may include at least one of the following: a 2G RAT network, a 3G RAT network, a 4G RAT network, or a 5G network. As another example, when a newer PLMN operator includes a 7G network operator, the disabled "older" RAT network may include at least one of the following: a 2G RAT network, a 3G RAT network, a 4G RAT network, a 5G network, or a 6G network.

[0077] It should also be understood that although this scenario is discussed in terms of 3GPP networks, the disabled “older” RAT networks may include at least one of non-3GPP RAT networks or 3GPP RAT networks.

[0078] Before explaining the exemplary embodiments in detail, certain general principles of wireless communication systems, their access systems, and mobile communication devices are referenced. Figure 1A , 1B To briefly explain points 2 and 3, we can aid in understanding the technology upon which the examples are based.

[0079] Figure 1A This diagram illustrates a schematic representation of a 5G system (5GS) configured to communicate with a terminal (e.g., a user equipment (UE)). The 5GS may be a 5G radio access network (5GRAN) or a next-generation radio access network (NG-RAN), a 5G core network (5GC), one or more application functions (AF), and one or more data networks (DN).

[0080] 5G-RAN may include one or more gNodeBs (GNBs) or one or more gNodeB (GNB) distributed element functions connected to one or more gNodeB (GNB) centralized element functions. This is referenced below. Figure 1B To explain in more detail.

[0081] 5GC can include the following entities: Network Slice Selection Function (NSSF); Network Exposure Function; Network Repository Function (NRF); Policy Control Function (PCF); Unified Data Management (UDM); Application Function (AF); Authentication Server Function (AUSF); Access and Mobility Management Function (AMF); and Session Management Function (SMF). Figure 1 also illustrates the various interfaces (N1, N2, etc.) that can be implemented between the components of the system.

[0082] Figure 1B The illustration shows an example communication environment in which exemplary embodiments of the present disclosure can be implemented.

[0083] Figure 1B An example communication environment 100 in which example embodiments of the present disclosure may be implemented is shown.

[0084] In communication environment 100, multiple communication devices (including user equipment 110 and 115 (also referred to herein as "terminals" or "terminal devices") and network device 120 (also referred to herein as "access network nodes") can communicate with each other. Network device 120 can serve a coverage area, referred to as cell 125. User equipment 110 can access the communication network via cell 125. In some example embodiments, both user equipment 110 and network device 120 can be configured to implement beamforming technology and communicate with each other via multiple beams.

[0085] Communication in communication environment 100 can be implemented according to any suitable communication protocol(s), including but not limited to cellular communication protocols such as first-generation (1G), second-generation (2G), third-generation (3G), fourth-generation (4G), fifth-generation (5G), and sixth-generation (6G), wireless local area network communication protocols (IEEE 802.11, etc.), and / or any other protocol currently known or to be developed in the future. Furthermore, communication can utilize any suitable wireless communication technology, including but not limited to: Code Division Multiple Access (CDMA), Frequency Division Multiple Access (FDMA), Time Division Multiple Access (TDMA), Frequency Division Duplex (FDD), Time Division Duplex (TDD), Multiple-Input Multiple-Output (MIMO), Orthogonal Frequency Division Multiplexing (OFDM), Discrete Fourier Transform Extended OFDM (DFT-s-OFDM), and / or any other technology currently known or to be developed in the future.

[0086] The term "terminal device" refers to any terminal device capable of wireless communication. By way of example and not limitation, a terminal device may also be referred to as a communication device, user equipment (UE), subscriber station (SS), portable subscriber station, mobile device, mobile station (MS), or access terminal (AT). Terminal devices may 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), machine-type communication (MTC) devices, 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. Terminal devices may also correspond to the mobile termination (MT) portion of an IAB node (e.g., a relay node). In the following description, the terms “terminal equipment”, “communication equipment”, “terminal”, “user equipment”, and “UE” are used interchangeably.

[0087] As used herein, the terms "network device" and "access network node" are used interchangeably and refer to a node in a communication network through which terminal devices access the network and receive services. Depending on the terminology and technology applied, a network device can refer to a base station (BS) or access point (AP), such as a Node B (NodeB or NB), an evolved Node B (eNodeB or eNB), an NR NB (also known as a gNB), a Remote Radio Unit (RRU), a Radio Header (RH), a Remote Radio Header (RRH), a relay, an Integrated Access and Backhaul (IAB) node, a low-power node (such as a femtonode or piconode), a non-terrestrial network (NTN) or non-terrestrial network device (such as satellite network device, low Earth orbit (LEO) satellites, and geostationary orbit (GEO) satellites), an airborne network device, etc. In some example embodiments, the Radio Access Network (RAN) split architecture includes a centralized unit (CU) and a distributed unit (DU) at the IAB donor node. An IAB node consists of a mobile termination (IAB-MT) portion and a DU portion. The mobile termination portion is represented by the UE facing the parent node, while the DU portion is represented by the base station facing the next-hop IAB node.

[0088] In some example embodiments, the link from network device 120 to user equipment 110 or 115 is referred to as DL, while the link from user equipment 110 or 115 to network device 120 is referred to as UL. Throughout this document, the link is also referred to as a “channel.” In DL, network device 120 is a Tx device (or transmitter), and user equipment 110 or 115 is an Rx device (or receiver). In UL, user equipment 110 or 115 is a Tx device (or transmitter), and network device 120 is an Rx device (or receiver). The link between user equipment 110 and another user equipment (not shown) is referred to as a sidelink (SL). In SL, one user equipment is a Tx device (or transmitter), and the other user equipment is an Rx device (or receiver).

[0089] Figure 2 The diagram illustrates how to enable network device 120 (such as...) Figure 1A and / or Figure 1B Network devices described in the document) and / or network functions (such as Figure 1A and / or Figure 1B Examples of control devices 200 that perform the operation of the network functions described herein. The control device may include at least one random access memory (RAM) 211a, at least one read-only memory (ROM) 211b, at least one processor 212, 213, and an input / output interface 214. At least one processor 212, 213 may be coupled to RAM 211a and ROM 211b. The at least one processor 212, 213 may be configured to execute appropriate software code 215. The software code 215 may, for example, allow the execution of one or more steps to perform one or more of the aspects described herein. The software code 215 may be stored in ROM 211b. Control device 200 may be interconnected with another control device 200 that controls another function of the network device. In some embodiments, each function in the network device includes control device 200. In some exemplary embodiments, device 200 may be implemented at network device 120, or may be network device 120.

[0090] Figure 3 An example of terminal 300 is illustrated, such as Figure 1A and / or Figure 1B User equipment 110 and 115 are shown above. Terminal 300 can be provided by any device capable of transmitting and receiving wireless signals, such as the user equipment described herein. Terminal 300 can provide, for example, data communication for carrying communications. The communication can be one or more of the following: voice, email, SMS, multimedia, data, machine data, etc.

[0091] Terminal 300 can receive signals via air or wireless interface 307 through appropriate means for receiving, and can transmit signals via appropriate means for transmitting wireless signals. Figure 3 In the diagram, the transceiver device is schematically represented by block 306. The transceiver device 306 may be provided, for example, via a wireless component and an associated antenna arrangement. The antenna arrangement may be located inside or outside the mobile device.

[0092] Terminal 300 may be provided with at least one processor 301, at least one ROM 302a, at least one RAM 302b, and other possible components 303 for performing its designed tasks with software and hardware assistance, including controlling access to systems (such as those described above in conjunction with Figure 1 and...). Figure 2 The network device provides access to a network access system and other communication devices, and facilitates communication with them. At least one processor 301 is coupled to RAM 302b and ROM 302a. At least one processor 301 can be configured to execute appropriate software code 308. For example, software code 308 may allow execution of one or more of the present aspects. Software code 308 may be stored in ROM 302a.

[0093] Processors, storage, and other related control devices may be provided on a suitable circuit board and / or in a chipset. This feature is indicated by reference numeral 304. The device may optionally have a user interface, such as a keyboard 305, a touchscreen or touchpad, or a combination thereof. Optionally, depending on the type of device, one or more of a display, speakers, and microphones may be provided.

[0094] In some exemplary embodiments, terminal 300 may be an apparatus including at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause user equipment 110, 115 to perform the examples or embodiments described in this document.

[0095] As described above, the following proposal suggests that a core network entity (e.g., a core network function) provides the UE with an identifier of at least one RAT that is disabled by the network operator of that core network entity, in order to address at least one of the aforementioned problems. The UE can use this identifier to select whether to hand over from the current RAT access network node to another RAT access network node. The UE can also use this identifier to select another RAT access network node when such a handover is required, and / or more generally, when the UE is made to perform mobility operations from the current RAT access network node.

[0096] For the sake of brevity, the access network node that will be configured to provide connection services to the UE via a disabled RAT will be referred to as a "fake" access network node, and the access network node that will be configured to provide connection services to the UE via a non-disabled RAT will be referred to as a "good" access network node.

[0097] The identifier of at least one RAT that is disabled by the network operator of the core network entity can be provided to the UE via a good access network node and / or via a fake access network node.

[0098] For example, the identifier of at least one RAT disabled by the network operator of the core network entity can be provided to the UE via a good access network node. In this case, the UE can determine that it is currently connected to the core network via the good access network node and simply store the identifier of the at least one RAT disabled by the network operator for future mobility operations (e.g., handover and / or multicarrier operations).

[0099] In other words, the UE can determine that it is currently connected to the core network via a good access network node and maintain the UE's Radio Resource Control (RRC) connection to the core network via that good access network node (e.g., the UE does not disconnect from the good access network node based on the received identifier of at least one RAT that is disabled by the network operator). The UE can later use the received identifier of at least one RAT that is disabled by the network operator during mobility operations to select at least one cell for connecting to the core network.

[0100] As described above, the identifier of at least one RAT disabled by the network operator of the core network entity can be provided to the UE via a dummy access network node. In this case, the UE can determine that it is currently connected to the core network via the dummy access network node and initiate (e.g., trigger) a mobility operation to be performed to access the core network via another access network node. The UE can use the identifier of at least one RAT disabled by the network operator to select another access network node. The UE can also store the identifier of at least one RAT disabled by the network operator for another (future) mobility operation (e.g., handover and / or multicarrier operation).

[0101] In other words, the UE can determine that it is currently connected to the core network via a dummy access network node based on the received identifier of at least one RAT that is disabled by the network operator, and disconnect from that dummy access network node (e.g., release the radio resource connection with that dummy access network node). After this disconnection, the UE can use the received identifier of at least one RAT that is disabled by the network operator to select at least one cell for connecting to the core network. The UE can also store the identifier of at least one RAT that is disabled by the network operator for another (future) mobility operation (e.g., handover and / or multicarrier operation).

[0102] In both example options, the UE can store the identifier of at least one RAT disabled by the network operator for future mobility operations (e.g., for selecting a cell as part of future mobility operations). The UE can store multiple identifiers in a priority list, which is used to ensure that the UE is not attached to a disabled RAT.

[0103] The method by which the identifier of at least one RAT disabled by the network operator can be signaled to the UE can be performed using at least one of the size, format, and / or structure of (multiple) Master Information Blocks (MIBs) or (multiple) System Information Blocks (SIBs) received by the UE. When a "fake" access network node is using a 2G or 3G RAT, the MIBs and SIBs received by the UE from the fake access network node will not match the 4G and / or 5G format, structure, and size expected to be received by the UE. Therefore, the UE can determine whether the access node from which it currently maintains a radio resource control connection (e.g., the access node from which the UE is currently receiving connection services) is a fake access network node or a good access network node.

[0104] In addition, system information blocks (such as SIB4 and / or SIB5) can provide the UE with neighboring cell information, such as the corresponding RAT(s) types supported by neighboring cells. The UE can also use such information included in such system information blocks to determine whether the access network node is a fake access network node (and therefore should not be selected by the UE for handover from the current access network node) or a good access network node (and therefore can be selected by the UE for handover from the current access network node).

[0105] Because SIBs are insecure, the information included within them can be modified by fake access network nodes. Therefore, relying solely on SIB / MIB information may not be sufficient for a UE to identify fake access network nodes. To ensure that fake access network nodes do not use tampered SIB / MIB information to attach the UE to a disabled RAT, the UE can assign a higher weight to the received disabled RAT information compared to the information received from the SIB / MIB. Even when the UE receives conflicting information from different sources, it can still decide to search for RATs that are not disabled.

[0106] To enhance the security of such network configurations, core network functions can enable the identifier of at least one RAT disabled by the network operator to be provided to the UE in signaling that cannot be decoded by the access network node (e.g., the identifier of at least one RAT disabled by the network operator can be signaled using non-access stratum signaling).

[0107] For example, such signaling can be useful in situations where the UE is currently connected to an untrusted access network node and / or is considered to pose a security risk because the access network node is unable to successfully modify the identifier of at least one RAT that is disabled by the network operator in order to insert and / or remove at least one RAT from at least one RAT that is disabled by the network operator.

[0108] In other words, when a UE attempts to attach to the serving network, the serving network uses the first secure NAS message sent from the AMF to the UE to provide information about disabled RATs included in the response to the attachment request, ensuring that no fake access network node can modify this information. Therefore, the NAS security context established between the UE and the core network to which the UE is attaching helps ensure that this information is not tampered with even when a fake access network node is acting as a man-in-the-middle.

[0109] As another example, when the UE is in idle mode and receives a Radio Resource Control Redirect (RRC_Redirect) message, the UE checks the list of disabled RATs to ensure that the redirection is not directed at an access network node operating according to a RAT on the list of disabled RATs. If the access node receiving the RRC_Redirect message is indeed operating according to a RAT on the list of disabled RATs, the UE can ignore or reject the redirection message.

[0110] The potential features of the above methods will refer to Figures 4 to 11 Let's illustrate with an example.

[0111] First example method reference Figure 4 To illustrate.

[0112] Figure 4 The diagram illustrates signaling that can be executed between UE 401, "dummy" access network node 402, "real" access network node 403, and core network function 404. Access network nodes 402 and 403 may include, for example, any node in the access network that provides connectivity services to the core network to the UE. Access network nodes may include, for example, gNBs, femtonodes, etc. "Dummy" access network node 402 may include an access network node operating using outdated communication protocols (e.g., 2G and / or 3G and / or 4G) with weaker security procedures compared to the "good" access network node 403 (e.g., which operates using 5G and / or 6G and / or above).

[0113] Sections 4001 to 4004 involve the UE selecting an access network node to provide connectivity services to the core network.

[0114] During period 4001, UE 401 is powered.

[0115] During period 4002, the UE performs a cell detection and / or selection method. This cell detection and / or selection method can detect multiple cells (e.g., multiple coverage areas provided by at least one access network node), including cells provided by dummy access network node 402. These multiple cells can be detected by receiving information broadcast by at least one of these cells.

[0116] During period 4003, UE 401 determines to connect to the core network via dummy access network node 402. Following this determination in 4003, during period 4004, UE 401 performs a random access channel procedure to initiate a connection for connection service with dummy access network node 402. It should be understood that although UE 401 may have alternatively discovered and / or determined to connect via good access network node 403 during periods 4003 and 4004, a greater security issue arises when dummy access network node 402 is selected to provide connection service; therefore, this example is being considered.

[0117] After successful RACH procedures were performed between 4001 and 4004, procedures between 4005 and 4008 were performed.

[0118] During period 4005, the dummy access network node 402 signals to UE 401. This signaling may include a Radio Resource Control (RRC) connection establishment signaling message. In other words, this signaling may include the RRC connection establishment configuration used by UE 401 to connect with the dummy access network node 402.

[0119] During signaling 4006, UE 401 signals to dummy access network node 402. This signaling may include an indication from signaling 4005 that the RRC connection establishment configuration has been met. In other words, this signaling may include an RRC connection establishment completion signaling message. This signaling may include a Non-Access Stratum (NAS) registration request.

[0120] During signaling 4007, dummy access network node 402 signals core network function 404. This signaling may include the NAS registration request from signaling 4006.

[0121] During 4008, UE 401, dummy access network node 402, and core network function 403 exchange signaling to complete the NAS registration and authentication and NAS security context establishment process between UE 401 and core network function 403. It is assumed that UE primary authentication and NAS security context establishment are successfully completed during 4008 using the core network's Access and Mobility Management (AMF) functions.

[0122] During 4009, core network function 404 signals to UE 401. This signaling includes an indication that the NAS registration process of 4008 has been completed. This signaling may also include information about disabled Radio Access Technologies (RATs), such as indications that the security mechanisms of those RATs do not meet the minimum standards set by the core network operator. Because this information about disabled RATs is sent via a secure NAS connection, it cannot be tampered with or read by a fake access network node unless UE 401 can identify tampering (e.g., when a cyclic redundancy check performed by UE 401 fails later). In other words, information about disabled RATs can be signaled using signaling that presents the information about disabled RATs as confidentiality and integrity protection.

[0123] It should be understood that although the fake access network node 402 can still discard and / or tamper with the signaling of 4009, such interference with the signaling of 4009 will disrupt the NAS completion message to the point that UE 401 will be able to determine that NAS has not been successfully completed, and will therefore be prompted to perform a new cell reselection procedure. Such tampering may be considered a temporary denial of service. When the UE cannot receive information about a disabled RAT during 4009 (e.g., because it has been tampered with), the UE can use signaling similar to that from 4003 to 4009 to connect to another access network node to receive the disabled RAT information from that other access network node.

[0124] During 4010, UE 401 uses the information about disabled RATs included in the signaling included in 4009 to update the UE's cell search and reselection criteria, so that access network nodes that are disabled RATs according to the information are not selected by UE 401 to provide connectivity services to core network nodes.

[0125] During 4011, UE 401 determines whether the RAT of the cell to which UE 401 is currently connected corresponds to the disabled RAT indicated in the information in 4009.

[0126] When determination 4011 causes the RAT of the cell to which UE 401 is currently connected to to not correspond to the determination of the disabled RAT indicated in information 4009, UE 401 continues to receive core network connection services via the dummy access network node.

[0127] When the determination in 4011 causes the determination that the RAT of the cell to which UE 401 is currently connected corresponds to the disabled RAT indicated in the information in 4009, the method proceeds to 4012.

[0128] During period 4012, UE 401 signals to dummy network node 402. This signaling may include signaling to cause the RRC connection established during periods 4005 to 4006 to be released. For example, the signaling for period 4012 may include an RRC connection release message.

[0129] The signaling of 4012 can include an indication of why the RRC connection was released. For example, the signaling of 4012 can include why the RRC connection was released due to an error, and / or a security issue, and / or some unknown reason. UE401 can also remove the cell to which UE401 is currently connected from the UE's cell priority list.

[0130] During 4013, UE 401 performs cell search and / or cell selection procedures (such as 4002 to 4003), except in cases where cell selection is performed to avoid using those cells for which RAT operations are indicated to be disabled. This can be performed using the updated cell priority list from 4012.

[0131] After a new cell (e.g., a cell provided by good access network node 403) has been selected during period 4013, UE 401 performs the random access channel access procedure using good access network node 403 during period 4014.

[0132] During 4015, UE 401 establishes a NAS security context with core network function 404 via good access network node 403.

[0133] During 4016, UE 401 establishes an access layer security context with the cell provided by the good access network node 403.

[0134] UE 401 can then move to RRC idle mode during 4017.

[0135] At some point during UE operation, dummy access network node 402 can signal UE 401 to perform an RRC redirect (e.g., during 4018). This RRC redirect signaling can be configured to request UE 401 to signal core network function 404 via dummy access network node 402.

[0136] UE 401 can be configured to disregard such RRC redirection messages when UE 401 determines that the RRC redirection message was signaled by a cell using a disabled RAT. The absence of compliance is indicated by 4019. In some examples, UE 401 can respond to signaling 4018 (not shown) with an error message.

[0137] exist Figure 4In the example, because the disabled RAT information is sent above the NAS registration completion message, any UE will receive information about the disabled RAT every time it connects to the core network. Whether the disabled RAT information is included in the NAS signaling (and / or what type of disabled RAT information is included in the NAS signaling) may vary depending on the tracking area.

[0138] For example, network operators can configure this information about disabled RATs in the core network. The configured information can be based on the region where a particular RAT is disabled. This configuration can be in the UDM and / or AMF. The configuration in the UDM may not cover all tracking region-specific disabled information.

[0139] Cell (re)selection information can also be used during handover to ensure that the UE does not connect to a BTS that provides services for a RAT that has been disabled by the operator in the area.

[0140] The above Figure 4 The example illustrates that NAS signaling can be used to provide RAT-disabled information to user equipment. A range of different procedures can be used for this. Two of these procedures could be, for example, the Bootstrap Roaming (SoR) service operation and the User Parameter Update (UPU) service operation.

[0141] SoR service operation example reference Figure 5 To illustrate, and using the terminology corresponding to the service operations described in Clause 4 of 3GPP TS 23.502.

[0142] In more detail, Figure 5 The illustration depicts a method for signaling disabled RAT information from the Home Public Land Mobile Network (HPLMN) to the visited PLMN (VPLMN). Figure 5 In the example, the disabled RAT information (indicating at least one RAT that has been disabled by the HPLMN) uses information about bootstrapping to signal this. The signaling for the disabled RAT information and bootstrapping information can be executed using signaling that cannot be read and / or modified by the access network node that connects the UE to the VPLMN. For example, the signaling for the disabled RAT information and bootstrapping information uses control plane-based signaling.

[0143] Figure 5 The diagram illustrates the signaling that can be executed between UE 501, Visited Public Land Mobile Network (VPLMN) AMF 502, Home Public Land Mobile Network (HPLMN) AUSF 503, and HPLMN UDM 504.

[0144] During period 5001, UE501 signals VPLMN AMF 502 to notify of the registration request.

[0145] 5002 to 5006 relate to the registration process defined in Clause 4.2.2.2.2 of 3GPP TS 23.502.

[0146] During 5002, UE 501, VPLMN AMF 502, HPLMN AUSF 503, and HPLMN UDM 504 exchange signaling to perform the master authentication process.

[0147] During 5003, UE 501 and VPLMN AMF 502 exchange signaling for the NAS Security Mode Command (SMC) procedure.

[0148] During period 5004, VPLMN AMF 502 signals HPLM UDM 504. This signaling may include a registration request for registering the UE's connection access with HPLM UDM 504 via VPLMN AMF 502. This signaling operation may include a Nudm_UECM_Registration message.

[0149] During period 5005, HPLM NDM 504 signals VPLMN AMF 502. This signaling may include a response to signaling 5004 to confirm that the connection access of 5004 has been registered with the UDM. This signaling action may include a Nudm_UECM_Registration_Response message.

[0150] During period 5006, VPLMN AMF 502 signals HPLMMN UDM 504. This signaling can request access and mobility subscription information corresponding to the UE's subscription. This signaling may include a Nudm_SDM_Get service operation message.

[0151] During 5007, HPLM NUMBER UDM 504 determines to send a SoR (Soaring Roaming) message to VPLMN AMF 502.

[0152] During 5007, the HPLMN determined a list of preferred PLMN access technology combinations and optional additional SoR information. For example, the HPLMN… (e.g., Guided Roaming Connection Mode Control Information (SOR-CMCI) and a “Store SOR-CMCI in ME” indicator), or a list of security packets as described in TS 23.122. Additional SoR information (e.g., SOR-CMCI and “Store SOR-CMCI in ME” indicator) can only be added if the AMF supports a transparent SoR container.

[0153] It should be understood that the HPLMN UDM can determine that the UE is configured not to receive bootstrapping roaming information during initial registration, and can also determine that no changes are needed to the lists of "operator-controlled PLMN selectors with access technologies" and "disabled RAT information" stored in the UE. In this case (e.g., based on such determination), the HPLMN UDM may not include bootstrapping roaming information in the Nudm_SDM_Get response mentioned below, and therefore the following steps are not performed. The following operations can therefore be related to the situation where the HPLMN UDM determines that the UE is configured to expect bootstrapping roaming information.

[0154] 5008 to 5009 concern the protection of boot information sent from HPLMN UDM 504 to UE 501. To this end, the HPLMN UDM requests the HPLMN AUSF to provide security services to the HPLMN UDM to prevent the boot information from being read by the VPLMN. In other words, 5008 to 5009 concern protecting the boot information list from tampering or removal by the VPLMN.

[0155] During 5008, HPLMN UDM 504 signals HPLMN AUSF 503. HPLMN AUSF 503 may be selected by HPLMN UDM 504 based on a determination performed by HPLMN UDM 504 that HPLMN AUSF 503 currently stores the authentication key for UE 501. This signaling may include a request to obtain security information (such as an encryption key) for encrypted communication to signal terminal boot information. This signaling may be performed as part two of the Nausf_SoRProtection service operation. The signaling of 5008 may include the subscriber identifier of UE 501 (e.g., Subscription Permanent Identifier (SUPI)). The signaling of 5008 may include a list of boot information.

[0156] The signaling of 5008 may include an indication that UE 501 will be requested to provide an acknowledgment signal for the boot information provided to UE 501 from HPLMN UDM 504. In other words, HPLMN UDM can be configured to determine that the UE will acknowledge successful reception of the boot information list. If boot roaming information is received, HPLMN UDM accordingly sets an “ACK” indication (marked as the expected “SoR-XMAC-IUE” indication in 3GPP) in the Nausf_SoRProtection service operation message to signal that HPLMN UDM is requesting security protection for the boot information list from VPLMN.

[0157] During signaling 5009, HPLMN AUSF 503 signals HPLMN UDM 504. This signaling may include a response to signaling 5008. This signaling may include a Nausf_SoRProtection response service operation. This signaling may include a CounterSOR, which uses the authentication key (K) used in the authentication process between UE 501 and the network. AUSF CounterSOR is maintained for its entire lifespan. AUSF It is initialized when stored and used to derive SoR-MAC-I at the UE. UE This is used for SoR signaling acknowledgment (as further described below). This signaling may include a SoR-XMAC-IUE value that has been encrypted using the SoR-MAC-IAUSF method.

[0158] During 5010, HPLM NUMBER UDM 504 signals VPLMN 502. This signaling may include a response included in the signaling of 5009. For example, this signaling may include at least one of SoR-MAC-IAUSF or counterSoR. This signaling may include an indication that acknowledgment of SoR-MAC-IAUSF has been requested from UE 501. The signaling of 5010 may include a bootstrap list. The bootstrap list may include identifiers of disabled RATs. The signaling of 5010 may include the Nudm_SDM_GET_Response service operation.

[0159] In other words, the signaling in 5010 can include a SoR transparent container, which contains "disabled RAT information" from access and mobility subscription data, SoR-MAC-IAUSF, and CounterSoR. When the UDM requests confirmation of this signaling in 5010, the UDM temporarily stores the expected SoR-XMAC-IUE corresponding to SoR-MAC-IAUSF. For example, the SoR transparent container (currently defined in TS 23.502) Figure 9In .11.3.51.2A, it may include a “PLMN ID and Access Technology List” field. This “PLMN ID and Access Technology List” field can be modified relative to the current form of such a field to include information identifying at least one disabled RAT. Such a modified PLMN ID and Access Technology List field is... Figure 6 The image is shown in the middle.

[0160] As an alternative to identifying disabled RATs in the signaling of 5010, the signaling may include individual information elements, such as a list or security packet (if provided) of preferred PLMNs and access technology pairs in access and mobility subscription data, SoR-MAC-IAUSF, and CounterSoR.

[0161] During 5011, VPLMN AMF 502 signals to UE 501. This signaling may include a registration acceptance message. This signaling may include a Guided Roaming (SoR) header. This signaling may include a guide list that includes "Disabled RAT Information" from the access and mobility subscription data, SoR-MAC-IAUSF, and CounterSoR.

[0162] In other words, when the SoR transparent container is received from the UDM during 5010, the VPLMN AMF includes the received SoR transparent container in the registration acceptance message sent by the VPLMN AMF to the UE 501. When a list of preferred PLMN and access technology pair combinations is received from the UDM instead of an identifier of a disabled RAT, the VPLMN AMF can construct a SOR protection based on the ACK indication and the list of preferred PLMN / access technology combinations, using the "disabled RAT information" or security packet received from the UDM (if provided), and include it in the SOR transparent container. The vPLMN should also include SoR-MAC-IAUSF and CounterSoR (both also received from the UDM) in the constructed SoR transparent container and deliver the constructed SoR transparent container to the UE in the registration acceptance message.

[0163] The purpose of the SOR transparent container information element in the registration acceptance message is to provide a list of preferred PLMN / access technology combinations (or an HPLMN indication stating "no change is required to the 'operator-controlled PLMN selector and access technology' list stored in the UE and therefore no preferred PLMN / access technology combination list is provided"), or security packets (see Annex C of 3GPP TS23.122), and optional indications of confirmation requests, SOR-CMCI, requests for the received SOR-CMCI to be stored in the ME, and SOR-SNPN-SI (or an indication of the subscribed SNPN or HPLMN stating "no change is required to the SOR-SNPN-SI stored in the UE and therefore no SOR-SNPN-SI is provided"). The purpose of the SOR transparent container information element in the registration completion message is to indicate to the UE that confirmation of successful reception of the SOR transparent container information element in the registration acceptance message has been requested, and to indicate mobile device support for the SOR-CMCI and mobile device support for the SOR-SNPN-SI.

[0164] When used during NAS transmission, the content of the SOR transparent container information element is included in the payload container information element of the downlink NAS transmission message and is used to provide a list of preferred PLMN / access technology combinations, as well as optional indications of acknowledgment requests, SOR-CMCI, requests that the received SOR-CMCI be stored in the ME, and SOR-SNPN-SI. The content of the SOR transparent container information element in the payload container IE of the UL NAS transmission message is used to indicate to the UE the acknowledgment of successful reception of the SOR transparent container IE in the DL NAS transmission message, and to indicate to the ME support for SOR-CMCI and SOR-SNPN-SI.

[0165] During period 5012, after receiving a registration acceptance message with a SoR transparent container from the AMF during period 5011, the UE calculates the "SoR-MAC-IAUSF" value on the SoR transparent container, which includes CounterSoR and the SoR header, in the same manner as AUSF (as specified in Annex A.17 of TS 33.501), and verifies whether the calculated SoR-MAC-IAUSF matches the SoR-MAC-IAUSF value received in the registration acceptance message. Based on the SoR-MAC-IAUSF verification result, the UE's behavior is specified in TS23.122. The received "Disabled RAT Information" is stored at the UE (e.g., at the Universal Subscriber Identification Module (USIM) and / or the Mobile Equipment (ME).

[0166] In this example, the UDM has requested confirmation from the UE, and the UE has verified that the SoR transparent container received during period 5012 has been provided by the HPLMN. Then, during period 5013, UE 501 sends a registration completion message to the HPLMN AMF 502. More specifically, UE 501 generates a SoR-MAC-IUE (as specified in Annex A.18) and includes the generated SoR-MAC-IUE in the SoR transparent container sent to the HPLMN AMF 502.

[0167] During period 5014, VPLMN AMF 502 signals HPLM UDM 503. This signaling may include a Nudm_SDM_Info request message to the UDM. When a transparent container including a SoR-MAC-IUE is received in the registration completion message and VPLMN AMF 502 supports SoR transparent containers, VPLMN AMF 502 includes the received SoR transparent container from 5013 in the SoR transparent container in the Nudm_SDM_Info request message. When VPLMN AMF 502 does not support SoR transparent containers, VPLMN AMF 502 includes the received SoR-MAC-IUE in the received SoR transparent container in the Nudm_SDM_Info request message.

[0168] During 5015, HPLMN UDM 504 compares the SoR-MAC-IUE received in the signaling of 5014 with the expected SoR-XMAC-IUE temporarily stored by the UDM during 5010.

[0169] As mentioned above, the SoR service operation is merely an example of how disabled RAT information can be signaled to the UE using protected signaling. Another example of signaling disabled RAT information is to update the service operation using user parameters, such as those defined in 3GPP TS 33.501 Part 6.15 (where the SoR service operation is also described in TS 33.501 Part 6.14).

[0170] At least some of the examples above are referenced below. Figures 7 to 11 This is to illustrate the point. Therefore, it should be understood that the above provides a non-limiting example of how the features described below can be implemented in the example system. It should also be understood that the above examples provide context for understanding how some of the features described below can be implemented in the example system.

[0171] Figures 7 to 8 A first example of devices that can communicate with each other is shown.

[0172] Figure 7 This illustrates operations that can be performed by a device for a user equipment. The user equipment can be referenced as described above. Figure 3 As stated above.

[0173] During phase 701, the device receives, via a first access network node of the first network, the identifier of at least one radio access technology not supported by the core network from the core network function of the core network. The core network function may include... Figure 8 The core network functions.

[0174] During 702, the device uses the received identifier to select an access network node for connecting to the core network.

[0175] As described above, the apparatus can use various methods for determining the current radio access technology for an access network node (e.g., a first access node or another network node). These methods may include, for example, receiving a system information block and / or a master information block broadcast by the access network node, the system information block and / or the master information block indicating the RAT parameters of the broadcasting access network node; and / or receiving information from the access network node indicating (e.g., identifying) the RAT parameters of at least one adjacent access network node. The apparatus can use the received RAT parameters to determine the corresponding RAT deployed for the access network node.

[0176] The selection of access network nodes in 702 can include: selecting a first access network node or another network node.

[0177] For example, when the first access network node is a "good" access network node, selecting an access node during 702 may correspond to determining to continue using the first (e.g., "good") access network node.

[0178] In other words, using the received identifier to select an access network node for connection to the core network may include: determining that the first network is not providing connectivity services to the core access network using at least one of the identified radio access technologies; and maintaining the connection to the core network via the first access network node.

[0179] Furthermore, when the first access network node is a "fake" access network node, selecting an access node during 702 may correspond to releasing the current RRC connection with the first access node and selecting another access network node for connection to the core network (e.g., using the received identifier to select another access network node by excluding access network nodes that deploy at least one of the at least one radio access technologies not supported by the core network).

[0180] In other words, using the received identifier to select an access network node for connecting to the core network may include: determining that a first network is providing connectivity services to the core access network using at least one identified radio access technology; and switching from the first access network node to a second access network node (e.g., performing a mobility operation, such as a handover) for connecting to the core network, wherein the first access network node and the second access network node are different access network nodes. The apparatus may select the second access network node for connecting to the core network based on the determination that the second access network node is operating according to a radio access technology not identified in the received identifier from the core network function. Furthermore, the handover may include: releasing a radio resource connection with the first access network node; and establishing a radio resource connection with the second access network node.

[0181] For both examples, the UE can perform a new selection operation based on the disabled RAT information received during 701 signaling notification (e.g., using the UE's updated priority list as described above).

[0182] In other words, the device can determine whether to switch from the current access network node to another access network node for connection to the core network; and use the received identifier to select another network node.

[0183] In all of the examples above, receiving the identifier may include receiving the identifier via signaling that is protected by confidentiality (e.g., encrypted or unreadable) and integrity (e.g., unmodifiable) by the first access network node.

[0184] In all the examples above, receiving the identifier can include receiving the identifier via non-access stratum signaling. Non-access stratum signaling can include SoR service operations and / or user parameter update service operations.

[0185] As described above, the UE can also receive a redirection request from a third access network node, which is used to cause the UE to signal to the core network through the third access network node instead of the current access network node. When the UE determines that the third access network node is operating using a radio access technology corresponding to one of the identified radio access technologies under 701, the UE can ignore the redirection request. When the UE determines that the third access network node is not operating using a radio access technology corresponding to the identified radio access technology, the UE can disable the redirection (e.g., be caused to signal to the core network through the third access network node instead of the current access network node).

[0186] In other words, the UE can receive an indication from the third access network node to connect to the core network through the third access network node; and determine whether to connect to the core network through the third network node based on the received identifier and the determined radio access technology provided by the third access network node.

[0187] Figure 8 The illustration depicts operations that can be performed by means of devices used for core network functions. These core network functions may include, for example, access and mobility management functions and / or unified data management functions, and / or other core network functions. Core network functions may correspond to... Figure 7 The core network function. The function of the core network function device can be combined with... Figure 2 The aforementioned device causes this.

[0188] During 801, the device sends an identifier of at least one radio access technology not supported by the core network to the user equipment via a first access network node. The user equipment can correspond to... Figure 7 User equipment.

[0189] Sending the identifier may include sending the identifier via signaling that is protected for confidentiality and integrity by the first access network node.

[0190] Sending an identifier may include sending the identifier via non-access stratum signaling.

[0191] exist Figure 7 and Figure 8 In any of the examples (e.g., all and / or one of them), the identifier can be included in the registration response message.

[0192] exist Figure 7 and Figure 8 In any of the examples (e.g., all and / or one of them), the identifier may be included in the signaling for the roaming service operation and / or in the signaling for the user parameter update service operation.

[0193] exist Figure 7 and Figure 8 In any of the examples (e.g., all and / or one of them), the identified wireless access technology may include at least one of the following: 2G, 3G, 4G and / or 5G.

[0194] exist Figure 7 and Figure 8 In any of the examples (e.g., all and / or one of them), the identifier of at least one radio access technology not supported by the core network can identify at least one radio access technology with a security mechanism that does not comply with the core network's security mechanisms. The network operator may have already configured an identifier for at least one radio access technology that identifies the at least one radio access technology.

[0195] exist Figure 7 and Figure 8 In any of the examples (e.g., all and / or one of them), core network functions may include at least one of the following core network functions: home public land mobile network or visited public land mobile network.

[0196] Figures 9 to 11 The illustration shows a second example of an interactive device.

[0197] Figure 9 The diagram illustrates operations that can be performed by a device used with a user equipment. The user equipment can be referenced as described above. Figure 3 As stated above.

[0198] During 901, the device receives, via a first access network node of the first network, an identifier of at least one radio access technology not supported by the home core network from the access and mobility management function of the visited core network. The access and mobility management function may correspond to the following... Figure 11 The aforementioned access and mobility management functions.

[0199] During 902, the device uses the received identifier to select an access network node for connection to at least one of the following: the visited core network or the home core network.

[0200] As described above, the apparatus can use various methods for determining the current radio access technology for an access network node (e.g., a first access node or another network node). For example, these methods may include: receiving a system information block and / or a master information block broadcast by the access network node, the system information block and / or the master information block indicating the RAT parameters of the broadcasting access network node; and / or receiving information from the access network node indicating (e.g., identifying) the RAT parameters of at least one adjacent access network node. The apparatus can use the received RAT parameters to determine the corresponding RAT deployed for the access network node.

[0201] The receiving identifier may include: a message receiving identifier received via registration.

[0202] Selecting an access network node in 902 can include selecting either a first access network node or another network node.

[0203] For example, when the first access network node is a "good" access network node, selecting an access node during 702 may correspond to determining to continue using the first (e.g., "good") access network node.

[0204] In other words, using the received identifier to select an access network node for connection to the core network may include: determining that the first network is not providing connectivity services to the visited core access network using at least one identified radio access technology; and maintaining the connection to the visited core network via the first access network node.

[0205] Furthermore, when the first access network node is a "fake" access network node, selecting an access node during 702 may correspond to releasing the current RRC connection with the first access node and selecting another access network node for connection to the core network (e.g., using the received identifier to select another access network node by excluding those access network nodes that have deployed at least one of the at least one radio access technologies not supported by the core network).

[0206] In other words, using the received identifier to select an access network node for connecting to the core network may include: determining that a first network is providing connectivity services to the visited core access network using at least one identified radio access technology; and switching from the first access network node to a second access network node (e.g., performing a mobility operation, such as a handover) for connecting to the visited core network, wherein the first access network node and the second access network node are different access network nodes. The apparatus may select the second access network node for connecting to the visited core network based on the determination that the second access network node is operating according to a radio access technology not identified in the received identifier from the core network function. Furthermore, the handover may include: releasing a radio resource connection with the first access network node; and establishing a radio resource connection with the second access network node.

[0207] For both examples, the UE can perform a new selection operation based on the disabled RAT information received during 701 signaling notification (e.g., using the UE's updated priority list as described above).

[0208] In other words, the device can determine whether to switch from the current access network node to another access network node for connection to the core network; and use the received identifier to select another network node.

[0209] In all of the examples above, receiving the identifier may include receiving the identifier via signaling that is protected by confidentiality (e.g., encrypted or unreadable) and integrity (e.g., unmodifiable) by the first access network node.

[0210] In all the examples above, receiving the identifier can include receiving the identifier via non-access stratum signaling. Non-access stratum signaling can include SoR service operations and / or user parameter update service operations.

[0211] As described above, the UE can also receive a redirection request from a third access network node, which is used to cause the UE to signal to the core network through the third access network node instead of the current access network node. When the UE determines that the third access network node is operating using a radio access technology corresponding to one of the identified radio access technologies under 701, the UE can ignore the redirection request. When the UE determines that the third access network node is not operating using a radio access technology corresponding to the identified radio access technology, the UE can disable the redirection (e.g., be caused to signal to the core network through the third access network node instead of the current access network node).

[0212] In other words, the UE can receive an indication from the third access network node to connect to the core network through the third access network node; and based on the received identifier and the determined radio access technology provided by the third access network node, determine whether to connect to the visited core network (or another core network) through the third access network node.

[0213] Figure 10 The illustration depicts operations performed by a device used for unified data management functions within the home core network. The unified data management function can be described in conjunction with the following... Figure 11 The aforementioned unified data management function. The function of the UDM device can be combined with... Figure 2 The aforementioned device causes this.

[0214] During period 1001, the device sends an identifier of at least one radio access technology not supported by the home core network to the user equipment via the access and mobility management functions of the visited core network. The user equipment can correspond to... Figure 9 User equipment. Access and mobility management functions can correspond to Figure 11 Access and mobility management functions.

[0215] Sending the identifier may include sending the identifier via signaling that is protected for confidentiality and integrity by the access network node.

[0216] Sending an identifier may include sending the identifier via non-access stratum signaling.

[0217] Figure 11 The diagram illustrates operations that can be performed by devices with access and mobility functions of the visited core network. Figure 11 The AMF in the text can correspond to Figure 9 and / or Figure 10 The AMF. The function of the AMF device can be achieved by combining... Figure 2 The aforementioned device causes this.

[0218] During 1101, the device receives data from the unified data management system of the core network (e.g., from...). Figure 10The device receives the identifier of at least one radio access technology that is not supported by the home core network.

[0219] During 1102, the device can communicate with the user equipment (e.g., via the first access network node) through the first access network node. Figure 9 The user equipment in the middle sends the received identifier.

[0220] Sending the identifier may include sending the identifier via signaling that is protected for confidentiality and integrity by the first access network node.

[0221] Sending an identifier may include sending the identifier via non-access stratum signaling.

[0222] exist Figures 9 to 11 In any of the examples (e.g., all and / or one of them), identification information may be included in the registration response message.

[0223] exist Figures 9 to 11 In any of the examples (e.g., all and / or one of them), identification information may be included in the signaling for the initiation of the roaming service operation and / or in the signaling for the user parameter update service operation.

[0224] exist Figures 9 to 11 In any of the examples (e.g., all and / or one of them), the identified wireless access technology may include at least one of the following: 2G, 3G, 4G and / or 5G.

[0225] exist Figures 9 to 11 In any of the examples (e.g., all and / or one of them), the identifier of at least one radio access technology not supported by the core network can identify at least one radio access technology with a security mechanism that does not comply with the core network's security mechanisms. The network operator may have already configured an identifier for at least one radio access technology that identifies the at least one radio access technology.

[0226] It should be understood that the device may include or be coupled to other units or modules used for transmission and / or reception, such as wireless components or wireless heads. Although the device has been described as a single entity, different modules and memories may be implemented in one or more physical or logical entities.

[0227] It should be noted that while some embodiments have been described in conjunction with 5G networks, similar principles can also be applied to other networks and communication systems. Therefore, although some embodiments are described above by way of example with reference to certain example architectures for wireless networks, technologies, and standards, these embodiments can also be applied to any other suitable form of communication system besides those shown and described herein. In particular, as noted above, it should also be understood below that references to 5G in isolation are not limited to 5G. Rather, these references can include 5G and / or anything other than 5G. For example, it should be understood that references to 5G networks and / or 5G network entities include references to 6G networks and / or 6G network entities.

[0228] It should also be noted in this document that although exemplary embodiments have been described above, there are several variations and modifications that can be made to the disclosed solutions without departing from the scope of the invention.

[0229] 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 these elements, or at least any two or more of these elements, or at least all of the elements.

[0230] Generally, various embodiments can be implemented in hardware or special-purpose circuitry systems, software, logic, or any combination thereof. Some aspects of this disclosure can be implemented in hardware, while others can be implemented in firmware or software, which can be executed by a controller, microprocessor, or other computing device, although this disclosure is not limited thereto. While various aspects 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, these blocks, apparatuses, systems, techniques, or methods described herein can be implemented in hardware, software, firmware, special-purpose circuitry or logic, general-purpose hardware or controllers or other computing devices, or some combination thereof.

[0231] As used in this application, the term "circuit system" may refer to one or more or all of the following: (a) Hardware circuit implementation only (such as implementation only in analog and / or digital circuit systems) and (b) A combination of hardware circuitry and software, such as (if applicable): (c) A combination of (multiple) analog and / or digital hardware circuits and software / firmware, and (d) Any part of the software (including the software of the multiple hardware processors, including the multiple digital signal processors), the software, and the multiple memories, which work together to enable a device (such as a mobile phone or a server) to perform various functions. (e) (multiple) hardware circuits and / or (multiple) processors (such as (multiple) microprocessors or a portion of (multiple) microprocessors) that require software (e.g., firmware) to operate, but may be absent when operation does not require the software.

[0232] This definition of "circuit system" applies to all uses of the term in this application, including in any claim. As another example, as used herein, the term "circuit system" also covers only hardware circuitry or a processor (or processors), or portions of hardware circuitry or a processor and / or their accompanying software and / or firmware implementations. The term "circuit system" also covers (e.g., 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.

[0233] Embodiments of this disclosure can be implemented by computer software executable by a data processor of a mobile device (such as a processor entity), or by hardware or a combination of software and hardware. Computer software or programs (also referred to as program products) (including software routines, applets, and / or macros) can be stored in any device-readable data storage medium and include program instructions for performing a specific task. A computer program product may include one or more computer-executable components that are configured to perform the embodiments when the program is run. The one or more computer-executable components may be at least one piece of software code or a portion thereof.

[0234] Furthermore, it should be noted that any block in the logic flow shown in the accompanying figures may represent a program step, or interconnected logic circuits, blocks and functions, or a combination of program steps and logic circuits, blocks and functions. Software may be stored on physical media (such as memory chips, or memory blocks implemented within a processor), magnetic media (such as hard disks or floppy disks), and optical media (such as, for example, DVDs and their data variants, CDs). Physical media are non-transitory media.

[0235] As used herein, the term “non-transient” refers to a limitation on the medium itself (i.e., tangible, not signaling), rather than a limitation on the persistence of data storage (e.g., RAM vs. ROM).

[0236] The memory can be of any type suitable for the local technical environment and can be implemented using any suitable data storage technology, such as semiconductor-based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory, and removable memory. As a non-limiting example, the data processor can be of any type suitable for the local technical environment and can include one or more of the following: general-purpose computers, special-purpose computers, microprocessors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), FPGAs, gate-level circuits, and processors based on multi-core processor architectures.

[0237] Embodiments of this disclosure can be practiced in various components, such as integrated circuit modules. The design of integrated circuits is largely a highly automated process. Sophisticated and powerful software tools can be used to transform logic-level designs into semiconductor circuit designs ready to be etched and formed on a semiconductor substrate.

[0238] The scope of protection sought by the various embodiments of this disclosure is defined by the independent claims. Any embodiments and features described in this specification that do not fall within the scope of the independent claims are to be construed as examples that help to understand the various embodiments of this disclosure.

[0239] The foregoing description has provided a complete and informative description of exemplary embodiments of the present disclosure by way of non-limiting examples. However, various modifications and adaptations will become apparent to those skilled in the art when read in conjunction with the accompanying drawings and appended claims, given the foregoing description. Nevertheless, all such and similar modifications to the teachings of this disclosure will still fall within the scope of the invention as defined in the appended claims. In fact, further embodiments will also exist, including combinations of one or more embodiments with any other embodiments discussed above.

Claims

1. An apparatus for a user equipment, the apparatus comprising components for performing the following: The first access network node of the first network receives, via the access and mobility management function of the visited core network, an identifier of at least one radio access technology not supported by the home core network; and The received identifier is used to select an access network node for connection to at least one of the following: the visited core network or the home core network.

2. The apparatus of claim 1, wherein the component for receiving the identifier includes a component for receiving the identifier via a registration acceptance message.

3. The apparatus according to any preceding claim, wherein the component for using the received identifier to select an access network node for connection to the core network includes components for: It was determined that the first network was not providing connectivity services to the visited core access network using the identified at least one radio access technology; and Maintain the connection to the visited core network via the first access network node.

4. The apparatus according to any one of claims 1 to 2, wherein the component for using the received identifier to select an access network node for connection to the core network includes components for: Determining that the first network is using the identified at least one radio access technology to provide connectivity services to the visited core access network; and The system switches from the first access network node to the visited core access network via a second access network node, wherein the first access network node and the second access network node are different access network nodes.

5. The apparatus of claim 4, further comprising components for performing: Based on the determination that the second access network node is operating according to a radio access technology not identified in the identifiers received from the access and mobility management functions, the second access network node is selected for receiving core network access.

6. The apparatus according to any one of claims 4 to 5, wherein the component for switching comprises a component for: Release the radio resource connection with the first access network node; and Establish a wireless resource connection with the second access network node.

7. The apparatus according to any of the preceding claims further includes components for performing the following: Receive an instruction from the third access network node to connect to the core network via the third access network node; and Based on the received identifier and the determined radio access technology provided by the third access network node, it is determined whether to connect to the core network through the third network node.

8. An apparatus for unified data management functions of a home core network, the apparatus comprising components for performing the following: The identifier of at least one radio access technology not supported by the home core network is sent to the user equipment via the access and mobility management functions of the visited core network.

9. The apparatus of claim 8, wherein the component for transmitting the identifier comprises: A component for sending the identifier via signaling that is protected for confidentiality and integrity by the access network node.

10. The apparatus according to any one of claims 8 to 9, wherein the component for transmitting the identifier comprises: A component used to send the identifier via non-access stratum signaling.

11. An apparatus for access and mobility functions of a visited core network, the apparatus comprising components for performing the following: Receive from the unified data management of the home core network the identifier of at least one radio access technology not supported by the home core network; and The received identifier is sent to the user equipment via the first access network node.

12. The apparatus according to any of the preceding claims, wherein the received identifier is included in a registration response message.

13. The apparatus according to any of the preceding claims, wherein the received identifier is included in signaling for guiding roaming service operations and / or in signaling for user parameter update service operations.

14. The apparatus according to any of the preceding claims, wherein the identified wireless access technology includes at least one of: 2G, 3G, 4G and / or 5G.

15. The apparatus according to any of the preceding claims, wherein the identifier of at least one radio access technology not supported by the home core network identifies at least one radio access technology having a security mechanism that does not conform to the security mechanism of the home core network.

16. A method for an apparatus for a user equipment, the method comprising: The first access network node of the first network receives the identifier of at least one radio access technology that is not supported by the home core network from the access and mobility management function of the visited core network. as well as The received identifier is used to select an access network node for connection to at least one of the following: the visited core network or the home core network.

17. A method for an apparatus for a unified data management function used in a home core network, the method comprising: The identifier of at least one radio access technology not supported by the home core network is sent to the user equipment via the access and mobility management functions of the visited core network.

18. A method for access and mobility functions for a visited core network, the method comprising: Receive the identifier of at least one radio access technology that is not supported by the home core network from the unified data management of the home core network; as well as The received identifier is sent to the user equipment via the first access network node.

19. A computer program comprising instructions that, when executed by a computer of a user equipment, cause the computer to perform: The first access network node of the first network receives, via the access and mobility management function of the visited core network, an identifier of at least one radio access technology not supported by the home core network; and The received identifier is used to select an access network node for connection to at least one of the following: the visited core network or the home core network.

20. A computer program, comprising instructions that, when executed by a computer of a unified data management function belonging to the core network function, cause the computer to perform: The identifier of at least one radio access technology not supported by the home core network is sent to the user equipment via the access and mobility management functions of the visited core network.

21. A computer program, comprising instructions that, when executed by a computer of the access and mobility functions of a visited core network, cause the computer to perform: Receive from the unified data management of the home core network the identifier of at least one radio access technology not supported by the home core network; and The received identifier is sent to the user equipment via the first access network node.

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