Method for network selection optimization in a communication system

Abstract

: This invention describes a method for access device selection implemented in a wireless device by means of a computer program, the method comprising the following steps: receiving, by the wireless device, one or more access device selection configurations, storing, by the wireless device, the one or more access device selection configurations, and selecting, by the wireless device, one or more access devices based on the one or more access device selection configurations.

Description

[0001] 2024PF00676

[0002] 1 16.12.2025

[0003] METHOD FOR NETWORK SELECTION OPTIMIZATION IN A COMMUNICATION SYSTEM

[0004] FIELD OF THE INVENTION

[0005] This invention relates to a method, apparatus, and system for operating a wireless device such as a user equipment to optimize network and cell selection procedures and manage network defined radio access technology restrictions and the conflicts thereof in a wireless system such as a cellular system or the like.

[0006] BACKGROUND OF THE INVENTION

[0007] In conventional cellular networks, a primary station serves a plurality of secondary stations located within a cell served by this primary station. Wireless communication from the primary station towards each secondary station is done on downlink channels. Conversely, wireless communication from each secondary towards the primary station is done on uplink channels. The wireless communication can include data traffic (sometimes referred to User Data), and control information (also referred sometimes as signalling). This control information typically comprises information to assist the primary station and / or the secondary station to exchange data traffic (e.g. resource allocation / requests, physical transmission parameters, information on the state of the respective stations).

[0008] In the context of cellular networks as standardized by 3GPP, the primary station is referred to a base station, or a gNodeB (or gNB) in 5G (NR) or an eNodeB (or eNB) in 4G (LTE). The eNB / gNB is part of the Radio Access Network RAN, which interfaces to functions in the Core Network (CN). In the same context, the secondary station corresponds to a mobile station, or a User Equipment (or a UE) in 4G / 5G, which is a wireless client device or a specific role played by such device. The term “node” is also used to denote either a UE or a gNB / eNB.

[0009] Additionally, for example, in the case of PC5 interface or Sidelink communication, it is possible to have Direct communication between secondary stations, here UEs. It is then also possible for UEs to operate as Relays to allow for example out of coverage UEs to get an inter-mediate (or indirect) connection to the eNB or gNB. To be able to work as a relay, a UE may use discovery messages to establish new connections with other UEs.

[0010] In current cellular systems, national roaming services play a crucial role to ensure seamless connectivity in areas where the primary network operator lacks coverage. Although, allowing national roamers unrestricted use of radio access technologies (RAT) can lead to potential interoperability issues, quality of service degradation and network congestion concerns. To limit UEs’ use of certain RATs, the 3GPP Core Network and Terminals Working Group 1 (CT1) introduced a new feature by which UEs’ RAT utilisation is controlled by the network. Namely, the network may provide the UE with 2024PF00676

[0011] 2 16.12.2025 an access device selection configuration (e.g., radio access technology utilisation control information) in which the network indicates which radio access technologies are allowed / restricted, and the scope of applicability of the configuration (e.g., to the PLMN from which the configuration was received, or from said PLMN and the PLMNs equivalent to it). However, there is still a need to determine how such a configuration is used by the radio access network of a UE overcoming problems arising from the integration.

[0012] SUMMARY OF THE INVENTION

[0013] An aim of the invention is to address this problem.

[0014] Another aim of the invention is to propose a method and an apparatus that can improve the integration of the radio access technology utilisation control information configuration in the RAN.

[0015] Thus, in accordance with an aspect of the invention, it is proposed a method for operating a User Equipment as claimed in claims 1 to 19, the apparatus of claim 20, and the computer program of claim 21.

[0016] It shall be understood that a preferred embodiment of the invention can also be any combination of the dependent claims or above embodiments with the respective independent claim.

[0017] These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter.

[0018] BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In the following drawings:

[0020] Fig. 1 schematically represents the overall cellular system including UEs, RAN, and core network;

[0021] Fig. 2 provides a schematic representation of a UE and its components; and

[0022] Fig. 3 schematically represents different entities involved in a non-terrestrial network;

[0023] Fig. 4 schematically represents a random-access procedure in a wireless network;

[0024] Fig. 5 schematically represents a signalling procedure by an access device; and Fig. 6 schematically represents the periodic transmission of SSB bursts;

[0025] Fig. 7 schematically represents examples of wireless devices according to some embodiments;

[0026] Fig. 8 schematically represents signalling between AS and NAS layer according to some embodiments of the invention;

[0027] Fig. 9 schematically represents signalling between PLMNs and UE according to some embodiments of the invention; and

[0028] Fig. 10 schematically represents how PLMN list(s) with priority order are updated using PLMN / RAT combination restrictions according to some embodiments of the invention. 2024PF00676

[0029] 3 16.12.2025

[0030] DETAILED DESCRIPTION OF EMBODIMENTS

[0031] Embodiments of the present invention are now described based on a cellular communication network environment, such as 5G or 6G. However, the present invention may also be used in connection with other wireless technologies.

[0032] Throughout the present disclosure, the abbreviation “gNB” (5G terminology) or “BS” (base station) or the term “access device” is intended to mean a wireless access device such as a cellular base station or a WiFi access point or a ultrawide band (UWB) personal area network (PAN) coordinator. The gNB may consist of a centralized control plane unit (gNB-CU-CP), multiple centralized user plane units (gNB-CU-UPs) and / or multiple distributed units (gNB-DUs). The gNB is part of a radio access network (RAN), which provides an interface to functions in the core network (CN). The RAN is part of a wireless communication network. It implements a radio access technology (RAT). Conceptually, it resides between a communication device such as a mobile phone, a computer, or any remotely controlled machine and provides connection with its CN. The CN is the communication network’s core part, which offers numerous services to customers who are interconnected via the RAN. More specifically, it directs communication streams over the communication network and possibly other networks.

[0033] Furthermore, the terms “base station” (BS) and “network” may be used as synonyms in this disclosure. This means for example that when it is written that the “network” performs a certain operation it may be performed by a CN function of a wireless communication network, or by one or more base stations that are part of such a wireless communication network, and vice versa. It can also mean that part of the functionality is performed by a CN function of the wireless communication network and part of the functionality by the base station.

[0034] It is further noted that throughout the present disclosure only those blocks, components and / or devices that are relevant are shown in the accompanying drawings. Other blocks have been omitted for reasons of brevity. Furthermore, blocks designated by same reference numbers are intended to have the same or at least a similar function, so that their function is not described again later.

[0035] A cellular system is a wireless communication system that consists of three main components: user equipment (UE), radio access network (RAN), and core network (CN). These components work together to provide voice and data services to mobile users over a large geographic area.

[0036] In conventional cellular networks, a primary station serves a plurality of secondary stations located within a cell served by this primary station. Wireless communication from the primary station towards each secondary station is done on downlink channels. Conversely, wireless communication from each secondary towards the primary station is done on uplink channels. The wireless communication can include data traffic (sometimes referred to User Data), and control information (also referred sometimes as signalling). This control information typically comprises information to assist the primary station and / or the secondary station to exchange data traffic (e.g. resource allocation / requests, physical transmission parameters, information on the state of the respective stations). In the context of 2024PF00676

[0037] 4 16.12.2025 cellular networks as standardized by 3GPP, the primary station is referred to a base station, or a gNodeB (or gNB) in 5G (NR) or an eNodeB (or eNB) in 4G (LTE). The eNB / gNB is part of the Radio Access Network RAN, which interfaces to functions in the Core Network (CN). In the same context, the secondary station corresponds to a mobile station, or a User Equipment (or a UE) in 4G / 5G, which is a wireless client device or a specific role played by such device. The term “node” is also used to denote either a UE or a gNB / eNB.

[0038] Additionally, for example, in the case of PC5 interface or Sidelink communication, it is possible to have Direct communication between secondary stations, here UEs. It is then also possible for UEs to operate as Relays to allow for example out of coverage UEs to get an inter-mediate (or indirect) connection to the eNB or gNB. To be able to work as a relay, a UE may use discovery messages to establish new connections with other UEs. Certain UEs may communicate with each other by using device-to-device communication, also known as sidelink communication using the PC5 interface that may rely on physical sidelink (PS) broadcast channel, PS shared channel, PS control, etc. Furthermore, the role of a relay node has been introduced in 3GPP. This relay node is a wireless communication station that includes functionalities for relaying communication between a primary station, e.g. a gNB and a secondary station, e.g. a UE. This relay function for example allows to extend the coverage of a cell to an out-of-coverage (OoC) secondary station. This relay node may be a mobile station or could be a different type of device. In the specifications for 4G, the Proximity Services (ProSe) functions are defined inter alia in TS 23.303, and TS 24.334 to enable - amongst others -connectivity for the cellular User Equipment (UE) that is temporarily not in coverage of the cellular network base station (eNB) serving the cell. This particular function is called ProSe UE-to-network relay, or Relay UE for short. The Relay UE relays application and network traffic in two directions between the OoC UE and the eNB. The local communication between the Relay UE and the OoC UE is called device-to-device (D2D) communication or Sidelink (also known as PC5) communication in TS 23.303 and TS 24.334. Once the relaying relation is established, the OoC-UE is, e.g., IP -connected via the Relay UE and acts in a role of “Remote UE”. This situation means the Remote UE has an indirect network connection to selected functions of the Core Network as opposed to a direct network connection to all Core Network functions that is the normal case. Furthermore, it has been introduced the role of a UE-to-UE relay node, i.e., a relay node re-laying the communication between two UE devices. The relay node relays the communications between UE devices. UEs may connect to the core network through a base station when in-coverage. In such relay scenarios, the relay devices may receive and store some information for some time before forwarding it towards the target device. This information that may be stored and forwarded may be discovery messages received from a source UE whereby the relay UE may release them at some point of time later. This information that may be stored and forwarded may be a SIB that may contain a timestamp.

[0039] User equipment (UE) is the device that a user uses to access the cellular system, such as a smartphone, a tablet, a laptop, loT device, or a wearable device. A UE typically may contain the following components: 2024PF00676

[0040] 5 16.12.2025

[0041] - A universal integrated circuit card (UICC), which stores the user's identification and authentication information, such as the subscription permanent identifier (SUPI) or credentials.

[0042] - A transceiver, which converts the digital signals from the processor into analog signals for transmission and reception over the air interface. The transceiver also performs modulation, demodulation, coding, decoding, and other signal processing functions.

[0043] A processor, which controls the operation of the UE and executes the applications and services that the user requests. The processor also communicates with the RAN and the CN using various protocols.

[0044] - A display, which shows the user the information and feedback from the UE, such as the signal strength, the battery level, the call status, the messages, the contacts, the menu, etc.

[0045] - A microphone and a speaker, which enable the user to make and receive voice calls, as well as use other audio features, such as voice mail, voice recognition, etc.

[0046] - A keyboard and / or a touch screen, which allow the user to enter and select commands, text, numbers, etc.

[0047] - A camera and / or a video recorder, which enable the user to capture and send images and videos, as well as use other multimedia features, such as video calling, video streaming, etc.

[0048] - A memory, which stores the data and programs that the user needs, such as the phone book, the messages, the photos, the videos, the applications, etc as well as a computer program to perform the operations of the RAN and CN protocols.

[0049] - A battery, which provides the power supply for the UE.

[0050] Fig. 2 provides a schematic representation of a UE and its components, e.g., UICC (201), processor (202), transceiver (203), memory (204), input devices (205) such as camera, microphone, etc and output devices (206) such as display, speaker, etc. Fig. 7 schematically represents wireless devices that may include the capabilities of a UE and / or a STA. Fig. 7a) represents AR / VR glasses; Fig. 7b) represents a connected vehicle; and Fig. 7c) represents a mobile phone. In these devices, a reflective intelligent surface (RIS) may be embedded, e.g., by covering and / or under the whole a part of the UE surface. This may be used, e.g., to better deal with interferences or improve wireless sensing.

[0051] A UE access the cellular network via the radio access network, as described below. Certain UEs may communicate with each other by using device-to-device communication, also known as sidelink communication using the PC5 interface that may rely on physical sidelink (PS) broadcast channel, PS shared channel, PS control channel, etc.

[0052] A UE may receive a configuration by means of different procedures:

[0053] Downlink control information (DCI) is a type of control information that is sent from the BS to the UE on the physical downlink control channel (PDCCH). DCI contains various parameters that instruct the UE how / when to decode and transmit data on the physical downlink shared channel (PDSCH) and the physical uplink shared channel (PUSCH), such as the resource allocation, the modulation and 2024PF00676

[0054] 6 16.12.2025 coding scheme. The UE needs to monitor the PDCCH in each subframe to detect and decode the DCI that is addressed to it.

[0055] Uplink control information (UCI) is a type of control information that is sent from the UE to the BS on the physical uplink control channel (PUCCH) or the physical uplink shared channel (PUSCH). UCI contains various feedback signals that inform the BS about the status and quality of the downlink transmission, such as the HARQ acknowledgments (ACKs), the channel state information (CSI), and the scheduling requests (SRs). The UE needs to encode and transmit the UCI according to the configuration and timing indicated by the BS.

[0056] Sidelink control information (SCI) is a type of control information that is sent from the UE to another UE on the physical sidelink control channel (PSCCH) in device-to-device (D2D) communication scenarios. The main functions of SCI include resource allocation, synchronization, channel quality reporting, .

[0057] Medium access control (MAC) control element (MAC CE) is a type of control information that is sent from the BS to the UE or vice versa on the MAC layer. MAC CE contains various commands or indications that regulate the MAC layer functions, such as the buffer status report (BSR), the timing advance command (TAC), the discontinuous reception (DRX) command, etc. The UE needs to process the MAC CE according to the MAC protocol and the configuration provided by the BS.

[0058] Radio resource control (RRC) command is a type of control information that is exchanged between the BS and the UE on the RRC layer. RRC Command contains various messages that modify / configure RRC parameters and / or initiate, modify, or release the RRC connection or the radio bearers between the UE and the BS, such as the RRC connection setup, the RRC connection reconfiguration, the RRC connection release, the security mode command, the mobility from E-UTRA command, the handover from E-UTRA preparation request, etc. The UE needs to respond to the RRC Command according to the RRC protocol and the configuration provided by the BS.

[0059] Non-access stratum (NAS) messages are used for signalling between UE and core network (CN) on the non-access stratum (NAS) layer. NAS messages enable functionality such as registration, session establishment, security, and mobility management. The UE needs to respond to the NAS Command according to the NAS protocol and the configuration provided by the CN.

[0060] UE parameter update (UPU) is a procedure between the UE and the home network that enables the home network to update configuration parameters in mobile phones and / or USIM using the UDM control plane procedure (TS 23.502). The UE can receive Parameters Update Data from the UDM after the UE has registered in the 5 G network.

[0061] Steering of Roaming (SoR) enables the home network to guide the user equipment (UE) when registering on a visited network. For detailed information about the interfaces and registration in the 5G System, refer to 3GPP TS.23.501 (Release 15)

[0017] and 3GPP TS 24.501 (Release 15)

[0018] , The 5G CP-SOR is activated during or after registration to update the UE's "Operator Controlled PLMN Selector 2024PF00676

[0062] 7 16.12.2025 with Access Technology" list via secure NAS messages, as directed by the home PLMN based on specific operator policies, such as preferred networks or UE location.

[0063] UE configuration update (UCU) is used to update configuration parameters as per TS 23.502 that may include Access and Mobility Management related parameters decided and provided by the AMF, UE Policy provided by the PCF. When AMF wants to change the UE configuration for access and mobility management related parameters the AMF initiates the procedure defined in clause 4.2.4.2. When the PCF wants to change or provide new UE Policies in the UE, the PCF initiates the procedure defined in clause 4.2.4.3. If the UE Configuration Update procedure requires the UE to initiate a Registration procedure, the AMF indicates this to the UE explicitly. The procedure in clause 4.2.4.2 may be triggered also when the AAA Server that performed Network Slice-Specific Authentication and Authorization for an S-NSSAI revokes the authorization.

[0064] Radio access network (RAN) is the part of the cellular system that connects the UEs to the CN via the air interface. The RAN consists of base stations (BSs). A base station (BS) is a fixed or mobile transceiver that covers a certain geographic area, called a cell. In 5G, a BS is also called a gNB (next generation node B). A BS can serve multiple UEs simultaneously within its cell, by using different frequencies, time slots, codes, or beams. A BS also performs functions such as power control, handover control, channel allocation, interference management, etc. A base station can be divided into two units: a central unit (CU) and a distributed unit (DU). The CU performs the higher layer functions, such as RLC, PDCP, RRC, etc. The DU performs the lower layer functions, such as PHY and MAC. The CU and the DU can be co-located or separated, depending on the network architecture and deployment. In cellular systems, a base station may be denoted, based on context, as a cell, or gNB.

[0065] The cell may also refer to the coverage area of a base station. A BS may have different coverage areas such as a macro cell (e.g. several kilometres wide), a pico cell (e.g., for a given location such as a stadium) or a femto cell for a small location (e.g., a home or part of it).

[0066] A base station may communicate with the core network. Since there can be base stations for different cellular systems, different interfaces are required. For instance, a base station, eNB, in a 4G Long Term Evolution (LTE) system (also known as Evolved Universal Mobile Telecommunications Systems (UMTS) Terrestrial Radio Access Network (E-UTRAN)) may interface with the 4G CN known as EPC through the corresponding interface. For instance, a base station, gNB, in a 5G system (i.e., 5G New Radio or Next Generation RAN) may communicate with the 5GC through a different interface. 4G and 5G base stations may communicate with each other directly or through their corresponding core networks.

[0067] The main protocols used between the UEs and the RAN are:

[0068] - The physical layer (PHY), which defines the characteristics of the air interface, such as the frequency bands, the modulation schemes, the coding rates, the frame structure, the synchronization, etc. 2024PF00676

[0069] 8 16.12.2025

[0070] - The medium access control (MAC) layer, which regulates the access of the UEs to the shared radio channel, by using techniques such as orthogonal frequency division multiple access (OFDMA), time division duplex (TDD), frequency division duplex (FDD), etc.

[0071] - The radio link control (RLC) layer, which provides reliable data transmission over the radio channel, by using techniques such as segmentation, reassembly, error detection, error correction, retransmission, etc.

[0072] - The packet data convergence protocol (PDCP) layer, which compresses and decompresses the headers of the data packets, encrypts and decrypts the data, and performs data integrity protection.

[0073] - The radio resource control (RRC) layer, which establishes, maintains, and releases the radio bearers between the UEs and the RAN, as well as exchanges the signaling messages for functions such as connection setup, handover, measurement reporting, security activation, etc.

[0074] A transmission / reception communication unit or transceiver may be used by BS and UE to transmit / receive data. Control data may be required for a physical broadcast channel, physical downlink control channel, etc. Data may be for the physical downlink shared channel.

[0075] Data may be encoded by the UE and / or BS to obtain data symbols and / or control symbols that may be exchanged over the wireless interface. The conversion from digital data into analog symbols may be done by the transmission / reception communication unit.

[0076] A medium access control control-element (MAC-CE) is a MAC layer communication element that is used to control the communication between wireless devices. A MAC-CE may be exchanged in a shared channel, e.g., the physical downlink / uplink / sidelink shared channel.

[0077] The communication between a UE and a base station or the communication between UEs (when sidelink is used) may involve the exchange of reference signals. Reference signals may include primary synchronization signal (PSS), a secondary synchronization signal (SSS), a physical broadcast channel demodulation reference signal (DMRS), a channel state information reference signal (CSI-RS). Core network (CN) is the part of the cellular system that connects the RAN to other networks, such as the Internet, or other cellular systems. The CN consists of two main (control / user) domains. The control domain is responsible for providing signalling and control functions for the UEs, such as authentication, authorization, mobility management, session management, etc. The control plane consists of several network functions (NFs), such as the access and mobility management function (AMF), the session management function (SMF), the unified data management (UDM), the policy control function (PCF), the network exposure function (NEF), and the authentication server function (AUSF). The access and mobility management function (AMF) is a NF that handles the registration, deregistration, connection management, and mobility management for the UEs. The session management function (SMF) is a NF that handles the establishment, modification, and release of the sessions for the UEs. The SMF also communicates with the user plane devices to perform functions such as IP address allocation, tunneling, QoS, etc. The unified data management (UDM) is a NF that stores and manages the user data, such as the 2024PF00676

[0078] 9 16.12.2025

[0079] SUPI, the service profile, the subscription status, etc. The policy control function (PCF) is a NF that provides the policy rules and charging information for the UEs, such as the access type, the service level, the data rate, the quota, etc. The network exposure function (NEF) is a NF that exposes the network capabilities and services to external applications and devices, such as the IMS, the Internet of Things (loT), etc. The authentication server function (AUSF) is a NF that performs the primary authentication with the by using credentials and the SUPI. The user domain is responsible for providing data and multimedia services to the UEs, by using packets and IP addresses. The user plane consists of two main functions: the user plane function (UPF) and the data network (DN). The user plane function (UPF) is a device that forwards the data packets between the UEs and the DNs, as well as performs functions such as tunneling, firewall, QoS, charging, etc. The data network (DN) is a network that provides access to the services and applications that the UEs request, such as the Internet, the IMS, etc.

[0080] A residential gateway (RG) is a device that connects a home network to an external network, such as the Internet or a cellular system. An RG typically provides functions such as routing, switching, firewall, NAT, DHCP, DNS, VPN, etc. An RG can also support various types of interfaces, such as Ethernet, Wi-Fi, Bluetooth, USB, etc. A cellular-capable RG is an RG that has a cellular interface, such as a UICC slot, a cellular modem, or an antenna, that enables it to access the cellular system as a backup or an alternative to the wired or wireless broadband connection. A cellular-capable RG can provide benefits such as: (1) Enhanced reliability, by switching to the cellular connection in case of a failure or a degradation of the broadband connection; (2) Increased bandwidth, by aggregating the cellular connection and the broadband connection to achieve higher data rates or QoS.

[0081] A multi-SIM subscription is a subscription that allows a user to have multiple SIMs (or eSIMs) that are linked to the same account and service profile. A user can use the multi-SIM subscription to access the cellular system from different devices, such as a smartphone, a tablet, a laptop, or a wearable device, without having to switch the SIM card or the device.

[0082] Overall system: Fig. 1 provides an overall description of a wireless system wherein devices 100, 102, and 128 can play the role of UEs. Device 102 is part of a cellular-capable RG providing connectivity to a home network 129 e.g., by means of a local area network and / or wireless local area network. Device 102 is served by base station 104.

[0083] The RAN 127 comprises base station 103 and serves UE 128. UE 128 may also be a UE to Network relay given access to remote UE 136 that is out of coverage of base station 103. UEs 134 and 136 also communicate with each other via a UE-to-UE relay 135. UE to UE communication via relays is enabled by means of side link communication / PC5 interface.

[0084] Within the RAN, the range of base station 103 is extended via smart repeater 137 and reflective intelligent surface (RIS) 138. Smart repeater 137 and RIS 138 give access to UE 142.

[0085] The RAN 143 includes base station 104 tand serves as wireless access infrastructure for the home network. Base station 104 also serves a mobile access device and / or UE as a UAV 139. UAV 139 may provide connectivity to remote UE 136. 2024PF00676

[0086] 10 16.12.2025

[0087] Furthermore, a satellite gateway 141 is shown that connects to satellite 140 and may provide connectivity services to remote UE 136 or UE 100.

[0088] In Fig. 1, the 5G core network 133 may include one or more an AMF 121, SMF 123, UPF 122, AUSF 124, UDM 125, PCF 131, NEF 132 and allows the connection to a data network 130.

[0089] In Fig. 1, a second core network 142, e.g., a legacy core network as a 4G core network, is also shown that may interface with the 5G core network 133, interface with base stations denoted eNB in 4G, and provide a connection to the data network 130. The legacy 4G core network is denoted EPC and may include one or more mobility management entities (MME), a serving gateway, a multimedia broadcast multicast service gateway, a broadcast multicast service center, a packet data network gateway, etc. The mobility management entity may handle the signalling between UE and the 4G CN and may interact with the home subscriber server (HSS) in charge of the storage and management of subscriber data and secrets. The MME may provide connection management, similar to the AMF in 5G. The serving gateway may be used to exchange user internet protocol messages whereby the serving gateway may interact with the packet data network gateway that is connected to IP services. Multiple protocols in 4G and 5G have similar features. For example, the 5G network registration and 4G attach registration message are initially sent by the UE to establish a connection between the UE and the CN, which involves sending an initial request from the UE with its identity and capabilities, receiving an authentication request from the CN with a challenge, sending an authentication response from the UE with a response, receiving an authentication result from the CN with an indication of success or failure, and sending a security mode command from the CN with the selected security algorithms. As a result of this connection establishment procedure, NAS and AS keys are derived from the K_AMF (5G) and K_ASME (4G) where K_AMF is managed by the AMF and K_ASME is managed by the MME. A UE may connect to a serving network or serving Public Land Mobile Network (PLMN). A UE may have a subscription with a home PLMN, and during the registration procedure, the (AMF of the) serving PLMN may forward the registration request to the (AUSF of the) home PLMN that may perform an initial authentication procedure between home PLMN and UE. If the authentication procedure is successful, keys are derived and the home PLMN may share derived credentials with the serving PLMN, including K_SEAF, that may be used to derive K_AMF, from which NAS keys and AS keys are derived. The registration request sent by the UE includes an identifier that can be used by the home PLMN to identify the UE. To prevent privacy vulnerabilities, the long-term subscriber’s identifier known as Subscriber Permanent Identifier (SUPI) may not be exchanged in the clear, but instead, either a Subscription Concealed Identifier (SUCI) or a pseudonym known as GUTI are exchanged with the AMF of the serving PLMN. The AMF of the PLMN may then forward the SUCI to the home PLMN so that the home PLMN decrypts / verifies it.

[0090] Satellite access: Fig. 1 depicts satellite 140 providing access to one or more UEs. Satellite access can be performed by means of non-terrestrial devices at different altitudes such as Low Earth Orbit (LEO), Medium Earth Orbit (MEO) or Geosynchronous Equatorial Orbit (GEO) satellites. Other types of non-terrestrial devices may include high-altitude platform station (HAPS) or unmanned aerial vehicle 2024PF00676

[0091] 16.12.2025

[0092] (UAVs) that may comprise a base station. Fig. 3 illustrates different elements including a GEO satellite

[0093] 302, a MEO satellite 303, a LEO satellites 304 and 304’, a UAV 305, all of them potential non-terrestrial mobile access devices giving coverage to wireless device (e.g., a UE) 301. GEO satellite 302 remains static over a given earth position while MEO and LEO satellites move. MEO satellites 303 have a slower moving vector 306 in relation to the earth compared with LEO satellites 304 / 304’ that have a faster moving vector 307 / 307’. A non-terrestrial gateway 308 is included that provides connectivity to the mobile access device via a feeder link 310. A mobile access device provides service to the wireless device via a service link 311. Two mobile access devices in the same orbit may communicate with each other via an intra-orbit-satellite link 312 while two mobile access devices in different orbits may communicate with each other via an inter-orbit-satellite link 313. Fig. 3 finally also includes a terrestrial access device 309 that may also provide connectivity to wireless device 301. The terrestrial access device 309, the wireless device 301, and non-terrestrial gateway are on the earth surface 314.

[0094] Non-terrestrial devices such as satellites distribute system information in specific SIBs, in particular, SIB31 in 4G and SIB19 in 5G. SIB19 information element as defined in TS 38.331 18.2.0. 2024PF00676

[0095] 16.12.2025 2024PF00676

[0096] 13 16.12.2025 2024PF00676

[0097] 16.12.2025

[0098] A UE in a cellular system performs an initial random-access procedure to connect an access device. The 5G random access procedure is illustrated by means of Fig. 4 wherein 401 represents a user equipment and 402 represents an access device. The access device distributes signals 402. Signals 402 can be distributed periodically or on demand. Signals 402 may comprise the Master Information Block (MIB) transmitted together with / in the physical broadcast channel (PBCH) and the synchronization signals. The MIB comprises:

[0099] MIB ::= SEQUENCE { systemFrameNumber BIT STRING (SIZE (6)), subCarrierSpacingCommon ENUMERATED {scs!5or60, scs30or!20}, ssb-SubcarrierOffset INTEGER (0..15), dmrs-TypeA-Position ENUMERATED {pos2, pos3}, pdcch-ConfigSIB 1 INTEGER (0..255), cellBarred ENUMERATED {barred, notBarred}, intraFreqReselection ENUMERATED {allowed, notAllowed}, spare BIT STRING (SIZE (1))

[0100] MIB and PBCH are transmitted as part of a Synchronization Signal Block, and the access device may transmit multiple SSBs through different beams, allowing the user equipment to determine 2024PF00676

[0101] 15 16.12.2025 the preferred beam, and once the preferred beam is obtained, retrieve the MIB, and use the information in the MIB to attempt to retrieve System Information Block 1 (SIB1) that may also be distributed periodically. The UE can the use the information in SIB1 to perform the random -access procedure selecting a preamble to indicate its intention to access the cell by means of message 404, e.g., preamble transmission. This message may use a random-access radio network temporary identifier (RA-RNTI). Upon reception of message 404, access device 402 replies with message 405, e.g., a random access response. This message may include a time advance field to adapt the transmission timing, a value matching the preamble used by wireless device 401, and a grant (communication resources) for the wireless device. The access device also assigns a temporary cell radio network temporary identifier (TC- RNTI). Prior to this message 405, the access device may send a PDCCH DCI message assigning resources (a communication grant). This message may be addressed using the RA-RNTI. Upon reception of message 405, wireless device uses the initial grant received in the previous message and the RA-RNTI to transmit a subsequent message 406, e.g, an RRCSetupRequest or PHY layer. This message may include a Contention Resolution Identifier (CRI). This message may be sent in the PUSCH. As a response, access device replies with message 407, e.g., RRCSetup, that includes / repeats the received CRI confirming that the access device has identified the access device. This message includes a Cell RNTI (C-RNTI). Next, wireless device replies with message 408, e.g., an RRCSetupComplete that includes the RegistrationRequest message, and UE capabilities.

[0102] MIB and PBCH are transmitted as part of a Synchronization Signal Block, and the access device may transmit multiple SSBs through different beams. Multiple SSBs transmitted through multiple beams form an SSB burst. The multiple SSBs in an SSB burst are transmitted sequentially in the first part of a frame. SSB bursts are transmitted periodically, typically every 20 ms, or more.

[0103] Fig. 5 schematically illustrates an access device 500 transmitting four beams, each of them transmitting an SSB, namely 501, 502, 503, and 504. A wireless device 505 can measure the signal strength, i.e., RSRP (Reference Signal Received Power), of the beams. This is illustrated by means of the graph in Fig. 5 where 501’, 502’, 503’, and 504’ represent the RSRP of beams 501, 502, 503, and 504, respectively, as measured by wireless device 505. Wireless device 505 can use this information to determine which one of the beams is the preferred beam for further communication, e.g., to perform the random access procedure.

[0104] Fig. 6 further schematically illustrates SSB bursts transmitted periodically. In this case, each SSB burst comprises four SSBs transmitted in the first part / half of every second frame. In this figure, frames are denoted as f, f+1, f+2, f+3,...A frame has atypical duration of 10 ms.

[0105] Resource grid: in a cellular network, such as a 5G network, the resource grid is a structured framework used to allocate and manage communication resources efficiently. It is characterized by a time-frequency matrix where each element, known as a resource element, is defined by its position in both time and frequency domains. The vertical axis represents frequency, segmented into subcarriers, which are spaced at intervals. The subcarrier spacing can vary depending on the deployment 2024PF00676

[0106] 16 16.12.2025 scenario, with common spacings being 15 kHz, 30 kHz, 60 kHz, 120 kHz, 240 kHz, and 480 kHz (corresponding to mu equal to 0, 1, 2, 3, 4, and 5, respectively). The horizontal axis of the grid represents time and is divided into frames, subframes, and slots, each frame has a duration of 10 ms and each subframe has a duration of 1 millisecond. Within these subframes, the time is further divided into slots. For mu, there are 2Amu symbols per subframe. Each slot typically spans 14 OFDM symbols. Each resource element in the grid, defined by the intersection of a time symbol and a frequency subcarrier, can carry a small portion of data, control information, or reference signals. These resource elements are grouped into larger units called Resource Blocks (RBs), which span 12 subcarriers in frequency and one slot in time. The allocation of these RBs is dynamically managed.

[0107] Reflective intelligent surfaces (RIS): may be used as part of the wireless infrastructure or as part of the wireless devices. RIS, often referred to as meta-surfaces, are advanced materials engineered with sub-wavelength structures that can manipulate electromagnetic waves in a controlled manner. These surfaces consist of an array of unit cells, each capable of adjusting its electromagnetic response through electronic control, thus enabling dynamic alteration of the wavefront of the incident signal. The wireless device can utilize the RIS to fine-tune the reflection properties of the wireless sensing signal, such as phase, amplitude, and polarization. By dynamically adjusting these parameters, the RIS can enhance signal strength, directivity, and overall signal quality. For instance, the RIS can focus the reflected signal towards the transmitter, significantly improving signal reception. This capability is particularly advantageous in urban environments where obstacles and interference are prevalent. Technical details of the RIS involve the implementation of tunable elements, such as varactor diodes or microelectromechanical systems (MEMS), in each unit cell. These elements allow real-time reconfiguration of the surface's electromagnetic properties in response to control signals from the wireless device. The control signals can be generated based on real-time analysis of the received signal's quality and contextual parameters, ensuring optimal reflection under varying conditions. The RIS can operate in various frequency bands, including sub-6 GHz and millimeter-wave (mmWave) frequencies, making it versatile for different wireless applications. Additionally, the RIS can incorporate sensing capabilities to monitor the environment and further refine the reflection parameters. For example, integrated sensors can detect changes in temperature, humidity, or the presence of obstacles, and adjust the reflection properties accordingly to maintain high signal quality.

[0108] Quality of Service: a wireless system may be used to transport data belonging to different types of applications such as Machine Type Communication (MTC), Critical Machine Type Communication (CMTC), Enhanced Mobile Broadband (EMB), or Fixed Wireless Access (FWA). MTC (e.g., smart meters, tracking,...) requires low bandwidth and non-latency critical, CMTC (e.g., industrial applications) has strict throughput, latency, and availability needs, EMB (VR / AR, 4K UDH, ...) and FWA (e.g., in the home) require high data rate, with low latency, and low end-to-end response time. In wireless network such as 5G the Quality of Service has to accommodate different applications such as EMB, MTC, ultra-reliable low latency communications. QoS is influenced by the entities involved in the 2024PF00676

[0109] 17 16.12.2025 communication, UE, RAN, UPF, and DN. Data exchanges between UE and DN are mapped to QoS flows, and each QoS flow is mapped to a 5G QoS Identifier (5QI) in TS 23.501 (Table 5.7.4-1) that describes resource types, priority, packet delay budget, packet error rate, maximum data burst volume. Network is configured to configure RAN and core network interfaces to achieve the requirements of a 5QI. QoS is applied to a data stream from the wireless physical layer to the core network. Between RAN and UPF, QoS is applied in terms of a QoS flow. QoS in the RAN is managed by means of Data Radio Bearers (DRB). A QoS flow on core network side is created by means of a PDU session establishment accept. The mapping between a QoS flow and a DRM is done by means of SDAP configuration in an RRC message (RRCSetup or RRCReconfiguration) The indication or identifier that connects the whole QoS pipe is called QoS flow identifier. Downlink traffic requires mapping IP messages and the QoS pipe, and this is done by the UPF. For each IP message or packet, the UPF checks (by means of a packet QoS assignment / detection rule) the packet information (source / destination / protocol / type of service / ...) and directs the IP packet to a QoS flow. The packet QoS assignment / detection rule is provided by SMF interacting with PCF. In the uplink, the UE performs a similar task by applying QoS rules provided in NAS messages (e.g., PDU session establishment) by the SMF or are pre-configured / derived by the UE.

[0110] Discontinuous reception (DRX) in cellular networks such as 5G is in two types, Idle mode DRX and Connected mode DRX. In Idle mode DRX, the UE wakes up to monitor for paging messages. If no paging message is detected, it sleeps further. In Connected DRX mode, the UE enters in sleep mode periodically and during the sleep period the UE is not required to monitor the Physical Download Control Channel. The access device configures the UE device with C-DRX parameters. Connected DRX approach reduces energy consumption of the device because it does not require monitoring the PDCCH periodically and it also reduces the transmissions of CSI or SRS signals, that also has a positive effect in the network / access devices load. There are two types of DRX cycles, long and short. A long DRX cycle consists of an on period and an off period. The on duration is in terms of milliseconds. The long DRC cycle may be configured or the long DRX cycle and short DRX cycles may be configured. The access device can configure the time (drx-onDurationTimer) during which the UE is awake and goes back to sleep if there is no PDCCH received. The access device can also configure a given drx-LongCycleStartOffiset to start to awake period at a subframe boundary and / or drx-SlotOffset relative to the subframe boundary. If there is activity in an awake period, the UE may remain awake some more time determined by the drx-InactivityTimer. Furthermore, the access device can configure long DRX cycle together with additional DRX cycle which is shorter than long DRX cycle. Configurable parameters include the drx-ShortCycle (duration of the short cycle) and drx-ShortCycleTImer that determines how many short cycles before the device should apply.

[0111] Data scheduling in a cellular network such as a 5G cellular network may be performed by means of a scheduler wherein the scheduler takes as input information such as measurements of UE / network, buffer status report, QoS requirements, associated radio bearers, or a scheduling request. In the downlink, data scheduling may be performed by means of dynamic scheduling and semi persistent 2024PF00676

[0112] 18 16.12.2025 scheduling (SPS). In dynamic scheduling, every data exchange in the Physical Downlink Shared Channel (PDSCH) is scheduled by means of a downlink control information (DCI) message in the Physical Downlink Control Channel (PDCCH). In SPS, the scheduling is done by means of an RRC message. In the uplink, scheduling can be performed by means of dynamic scheduling and configured scheduling (CS). In dynamic scheduling each Physical Uplink Shared Channel (PUSCH) is scheduled over DCI. In CS, the PUSCH transmission is scheduled via RRC message. Furthermore, a Scheduling Request message may be sent over the PUCCH (Physical Uplink Control Channel) or in an Uplink Control Information (UCI) in the PUSCH (Physical Uplink Shared Channel). An SR may be sent by a UE device when it has data to transmit. Upon reception, the access device can allocate resources (Uplink Grant by means of the Physical Downlink Control Channel. Upon resource allocation, the UE device can transmit data in the Physical Uplink Shared Channel.

[0113] Wireless sensing and integrated wireless sensing and communication: wireless systems are evolving to include wireless sensing capabilities. These wireless sensing capabilities may be implemented e.g. by a radar functionality in wireless communication involving one or more access devices (e.g., base stations (BS)) and / or one or more terminal devices (e.g., UEs). As an example, Frequency Modulated Continuous Wave (FMCW) mmWave radar systems can measure range, velocity, and angle of arrival (if two receivers are available) of objects in the scene which reflect radio waves. Such radar systems emit a chirp signal, e.g., a sine wave that increases in frequency over time. The chirp signal (e.g., a continuous wave pulse) has a bandwidth and a frequency increase rate. Generally, a continuous series of such chirps are emitted. The transmitted and received analogue chirp signals are mixed to generate an intermediate frequency (IF) signal which corresponds to the difference in frequencies of the two signals (outbound and inbound) and whose output phase corresponds to the difference in the phases of the two signals. Each surface of a scene or environment will therefore produce a constant frequency IF signal whose frequency relates to the distance to the surface (i.e., a first distance from the transmitter of the chirp signal to the surface plus a second distance from the surface to the receiver of the chirp signal). To resolve two surfaces at different distances, the two IF signals can be frequency resolved. A longer time window of the IF signal results in greater resolution. As the chirp time is related to its bandwidth (with constant chirp frequency change) the resolution of the radar is related to the chirp bandwidth. The IF signal may then be band pass filtered (to remove signals below some minimal range and frequencies above the maximum frequency for a subsequent analogue-to-digital converter (ADC)) and digitized prior to further processing. The upper frequency sensing range of the bandpass filter and ADC sets the maximum range that can be detected (i.e., IF frequencies increase with range). To detect vibrations, the phase of the IF signal is important, since the phase (i.e., the difference in phases of the transmitted and received chirp signals) is a sensitive measure of small changes in the distance of a surface. Small distance changes can be detected in the phase signal but may be indiscernible in the frequency signal. Moreover, phase difference measures between two consecutive chirp signals can be used to determine the velocity of the surface. As an example, a fast Fourier transform (FFT) processing can be performed across multiple 2024PF00676

[0114] 19 16.12.2025 chirp signals to enable separation of objects with the same range but moving at different velocities. A Fourier transform converts a signal from a space or time domain into the frequency domain. In the frequency domain the signal is represented by a weighted sum of sine and cosine waves. A discrete digital signal with N samples can be represented exactly by a sum of N waves. FFT provides a faster way of computing a discrete Fourier transform by using the symmetry and repetition of waves to combine samples and reuse partial results. This method can save a huge amount of processing time, especially with real -world signals that can have many thousands or even millions of samples. As a further example, angle estimation can be performed by using the phase difference between the received chirp signal at two separated receivers.

[0115] As another option, a channel state information (CSI) can be used, which is a measure of the phases and amplitudes of many frequencies detected at a receiver, thereby forming a complex ‘map’ of the radio environment, including effects of objects within that environment. CSI characterizes how wireless signals propagate from the transmitter to the receiver at certain carrier frequencies. CSI amplitude and phase are impacted by multi-path effects including amplitude attenuation and phase shift, e.g., by the displacements and movements of the transmitter, receiver, and surrounding objects and humans. In other words, CSI captures the wireless characteristics of the nearby environment. These characteristics, assisted by mathematical modeling or machine learning algorithms, can be used for different sensing applications. A radio channel may be divided into multiple subcarriers, as is done e.g. in 5G communication systems (using e.g. orthogonal frequency division multiplexing (OFDM)). To measure CSI, the transmitter may send long training symbols (LTFs), which contain pre-defined symbols for each subcarrier, e.g., in a packet preamble. When those LTFs are received, the receiver can estimate a CSI matrix using the received signals and the original LTFs. For each subcarrier, the channel can be modeled by y = Hx + n, where y is the received signal, x is the transmitted signal, H is the CSI matrix, and n is the noise vector. The receiver estimates the CSI matrix H using a pre-defined signal x and the received signal y after signal processing such as removing cyclic prefix, de-mapping and demodulation. The estimated CSI is then a three-dimensional matrix of complex values and this matrix represents an ‘image’ of the radio environment at that time. By processing a time series of such ‘images’ information on movements, locations and vibrations of objects can be extracted. Such a processing of a CSI matrix can be used for vital signs monitoring, presence detection, and human movement recognition. As an example, neural network like recognition techniques can be used to process the CSI matrix to perform such kinds of recognition.

[0116] It is noted that systems using channel state information (CSI) are somehow related to systems with FMCW mmWave radar. In a CSI-based system, the input signal X may be defined and the receiver may use the received signal Y to obtain H, i.e., as H = (Y - N) / X . In a FMCW mmWave radar, the transmitted signal Chirp X may also be predefined, and the receiver may uses the received signal Y to obtain a transfer function as H = Y / X . This last step is in fact somehow related to multiplying the locally computed chirp signal and the received chirp signal and applying a bandpass filter. According to 2024PF00676

[0117] 20 16.12.2025 various embodiments in this invention, the above-described wireless sensing techniques are implemented in a mobile communication system (e.g. 5G or 6G or other cellular or WiFi communication systems), while the functional coexistence of radar and communication operating in the same frequency bands is configured to avoid interference bandwidths. Thereby, radio sensing can be integrated into large-scale mobile networks to create perceptive mobile networks.

[0118] As another example, the sensing signal may consist of a number of pulses sent, e.g., at specific frequencies and timing (sensing signal parameter information) by a sensing transmitter. The sensing receiver may include a number of bandpass filters that allow identifying the sensing signal parameter information, e.g, timing and frequency of the received pulses. In particular, if the transmitter determines a given pseudo-random sequence of frequency / timing pulses and beams it, e.g., by means of beamforming, in a specific direction, and if the transmitter communicates to the receiver the timing / frequency, in general, the sensing signal parameter information, of the transmitted sensing signal, the receiver can use its bandpass filters to identify the reception of the same transmitted pulses, i.e., sensing signal, based on the received sensing signal parameter information.

[0119] The wireless sensing signal may be part of the synchronization signal block. For instance, the wireless sensing signal may be a reference signal included in the primary synchronization signal or in the secondary synchronization signal. It may consist of a number of reference signals and / or it may be a wide band signal. This wireless sensing signal can allow the access devices to determine the presence of a wireless device. The wireless device may also use this wireless sensing signal to determine the access device that is more suitable to (re-)select.

[0120] Wireless local area network technologies such as Wi-Fi allow devices to connect to the Internet or to each other without using cables. Wi-Fi is based on radio waves that are transmitted and received by a device called a wireless access point (AP). The AP acts as a hub that connects Wi-Fi enabled devices, such as laptops, smartphones, tablets, smart TVs, etc., to a wired network, such as a local area network (LAN) or the Internet.

[0121] The term Wi-Fi is a trademark of the Wi-Fi Alliance, an industry association that certifies products that comply with the IEEE 802.11 standards for wireless local area networks (WLANs). These standards define the physical and data link layers of the communication protocol, such as the frequency bands, modulation schemes, encryption methods, authentication mechanisms, and data rates used by WiFi devices. The most common Wi-Fi standards are 802. I la, 802.1 lb, 802. 11g, 802. 1 In, 802.1 lac, and 802.1 lax, which operate in different frequency bands (2.4 GHz, 5 GHz, or both) and offer different levels of performance and compatibility.

[0122] To use Wi-Fi, a device needs to have a wireless network interface card (NIC) that can send and receive radio signals. The NIC scans the available wireless channels and detects the presence of nearby APs. The device then selects an AP to connect to, based on factors such as signal strength, security settings, and network name (SSID). The device and the AP exchange information, such as the MAC address, IP address, encryption key, and password, to establish a connection. This process is called 2024PF00676

[0123] 21 16.12.2025 association. After the connection is established, the device can communicate with the AP and other devices on the same network, or access the Internet through the AP.

[0124] IEEE 802.1 In (Wi-Fi 4) provided new features such as MIMO and frame aggregation to increase throughput. IEEE 802. 1 lac (Wi-Fi 5) introduced wider bandwidth and MU-MIMO. IEEE 802.11 ax (WIFI-6) included OFDMA and BSS color or spatial reuse to use spectrum resources more efficiently. IEEE 802.11 ah introduced target wake time (TWT) to support low power loT applications by allowing STAs to go into sleep when not in a wake period after negotiation with AP. IEEE 802.1 Ibe (Wi-Fi 7) aims at improving throughput and latency operating in unlicensed bands between 1GHz and 7.125 GHz. Wi-Fi 7. Increases bandwidths up to 320 MHz, 4096 QAM modulation, and supporting up to 16 spatial streams in MU-MIMO with an improved sounding procedure. Wi-FI 7 also enables multiple resource units to be assigned to a single device. Furthermore, it includes an enhanced preamble with a universal SIG filed indicating the PHY version. It also extends the negotiated ack buffer size to 1024 bits. It also enables multilink operation (MLO) enabling multiple links between a station and an access point, for instance an AP can have two radios 2.4 and 5 GHz and use both of them for simultaneous transmission and / or reception with a multi-link capable device (MLD) capable station. Wi-Fi 7 also includes a restricted TWT providing predictable latency by assigning STAs to different rTWT types and making sure that other STAs do not transmit if they do not belong to a given rTWT type. Wi-Fi 7 also include multi-AP coordination performing, e.g., coordinated transmission, beamforming, or joint transmission.

[0125] For instance, in references to Fig. 1, devices 100, 101 and 102 can be Wi-FI access points and device 106 can be a wireless station. Station 106 and access point 101 are MLD and communicate with two links 126. Device 102 is a cellular capable residential gateway.

[0126] In current cellular systems, national roaming services play a crucial role to ensure seamless connectivity in areas where the primary network operator lacks coverage. Although, allowing national roamers unrestricted use of radio access technologies (RAT) can lead to potential interoperability issues, quality of service degradation and network congestion concerns. To limit UEs’ use of certain RATs, the 3GPP Core Network and Terminals Working Group 1 (CT1) introduced a new feature by which UEs’ RAT utilisation is controlled by the network. Namely, the network may provide the UE with an access device selection configuration (e.g., radio access technology utilisation control information) in which the network indicates which radio access technologies are allowed / restricted, and the scope of applicability of the configuration (e.g., to the PLMN from which the configuration was received, or from said PLMN and the PLMNs equivalent to it). However, there is still a need to determine how such a configuration is used by the radio access network of a UE overcoming problems arising from the integration.

[0127] For instance, the access device selection configuration is captured in a list of “PLMNs with associated RAT restrictions”, which the UE stores in its non-volatile memory, and said list may be frequently updated and / or deleted (e.g., if the USIM is removed). The combination(s) of PLMN(s) and radio access technology(ies) that are restricted are not to be considered as candidate PLMN / radio access 2024PF00676

[0128] 22 16.12.2025 technology(ies) for PLMN selection purposes, hence, the need to account for the presence of the list of “PLMNs with associated RAT restrictions” and its potential impact on other lists (e.g., list(s) of PLMNs in priority order) configured at the UE and used for network and / or cell selection.

[0129] For instance, another potential problem stems from the applicability of the restrictions indicated by the network providing the UE with the access device selection configuration. If the access device selection configuration indicates that the configuration is applicable e.g., to a PLMN (e.g., PLMNi) and to the PLMNs equivalent to it, and one of the PLMNs (e.g., PLMN2) in the list of Equivalent PLMNs to PLMNi, provisions the UE, or already has the UE configured with an access device selection configuration associated with it (i.e., PLMN2), then the UE may end up with different radio access technology restrictions in the two applicable access device selection configurations, hence the conflict.

[0130] Thus, an embodiment of this invention is illustrated in the context of Radio Access Technology (RAT) utilisation control and its impact on network / cell selection procedures, e.g., in relation to potential lists of priority order configured in the USIM or the ME, and management of the applicability and the potential conflicts which may arise from the RAT utilisation control configurations being provided by different PLMNs.

[0131] In a core embodiment of the invention that may be combined with other embodiments or implemented independently, a wireless device such as a UE may follow one or more of the following steps when selecting an access device:

[0132] 1. Receiving Configurations: The wireless device may receive one or more access device selection configurations from a network. These configurations may be transmitted through control messages, broadcast signals, or during the initial network attachment process. Each configuration may include various parameters such as radio access technologies (RAT) utilization control information, which specifies the allowed and / or restricted RATs.

[0133] 2. Storing Configurations: Upon receiving the configurations, the wireless device may store them in its non-volatile memory. This storage ensures that the configurations persist across device reboots and power cycles. The device may maintain a list of "PLMNs with associated RAT restrictions," which can be frequently updated or deleted based on network interactions or changes in the SIM card (e.g., when the USIM is removed).

[0134] 3. Combining Configurations: The wireless device may combine multiple configurations if it receives more than one. This combination process involves merging the parameters from different configurations into a coherent set of rules that the device can apply. The device may prioritize configurations based on their source (e.g., home PLMN vs. visited PLMN) or their validity period.

[0135] 4. Selection Based on Configurations: When selecting an access device, the wireless device may evaluate the stored configurations to determine the most suitable access device. The selection process may involve the following sub-steps:

[0136] - Scanning for Available Access Devices: The device may scan the available wireless channels to detect nearby access devices (e.g., Wi-Fi APs, cellular base stations). 2024PF00676

[0137] 23 16.12.2025

[0138] - Evaluating Signal Strength and Quality: The device may assess the signal strength and quality of the detected access devices to ensure reliable connectivity.

[0139] - Applying Configuration Rules: The device may apply the rules defined in the stored configurations to filter out access devices that do not meet the requirements (e.g., restricted RATs or nonpreferred PLMNs).

[0140] - Prioritizing Access Devices: The device may prioritize the remaining access devices based on factors such as network performance, security settings, and user preferences.

[0141] - Establishing Connection: The device may establish a connection with the selected access device, exchanging necessary information such as MAC address, IP address, encryption key, and authentication credentials.

[0142] This process of receiving, storing, combining, and selecting based on configurations may allow the wireless device to optimize its connectivity while adhering to network policies and restrictions.

[0143] Re-ordering lists of PLMNs with priority order based on PLMNs with associated RAT restrictions

[0144] According to clause 4.4.3 of TS 23.122, the Mobile Equipment (ME) shall utilise all the information stored in the SIM related to the PLMN selection e.g. "HPLMN Selector with Access Technology", "User Controlled PLMN Selector with Access Technology", "Forbidden PLMNs", and "Equivalent HPLMN", and also the extension of the “Forbidden PLMNs” list that it has stored locally on the ME if available. Additionally, the ME shall either utilise the “Operator controlled PLMN selection with Access Technology” that is stored locally on the ME, or the one stored in the SIM for the purpose of PLMN selection. In clause 4.4.3.1.1 of TS 23.122 concerned with Automatic Network selection mode procedure, it is described the order by which the UE performs the selection and attempts registration on other PLMN / access technology combinations; said order relies on several lists (e.g., EHPLMN list, User Controlled PLMN Selector with Access Technology, Operator Controlled PLMN Selector with Access Technology), which are stored in the USIM and / or the ME. In addition to these lists, NOTE 3 in clause 4.4.3.2.1 indicates that a PLMN and RAT combination that is included in the list of “PLMNs with associated RAT restrictions” is not to be considered as a candidate for PLMN selection. As such, the list of “PLMNs with associated RAT restrictions”, if available, may have an impact on the priority order of PLMN selection candidates.

[0145] Thus, in an embodiment, that may be combined with other embodiments or used independently, the UE may be configured to change the priority order of PLMN / access technology combinations in one or more of the lists (e.g., EHPLMN list, User Controlled PLMN Selector with Access Technology, Operator Controlled PLMN Selector with Access Technology) based on whether a PLMN / access technology which figures in one of these lists, is also included in the list of “PLMNs with associated RAT restrictions”. 2024PF00676

[0146] 24 16.12.2025

[0147] It is worth noting that the specificity of access technologies differs between the access technologies indicated in “PLMNs with associated RAT restrictions” and the ones indicated in lists e.g., User / Operator Controlled PLMN Selector with Access Technology. The former is described in the RAT utilization control information as follows:

[0148] 8 7 6 5 4 3 2 1 octet 1 octet 2 octet 3 octet 4

[0149] Figure 9.9.3.3a. 1: RAT utilization control information element

[0150] Whereas the list of User controlled PLMN selector with Access Technology, is described in 4.2.5 of TS 31.102, as follows: 2024PF00676

[0151] 25 16.12.2025

[0152] With the 2 bytes used to select the access technology being coded as follows:

[0153] Byte 5N-l:

[0154] Byte 5N:

[0155] Such that, if b is set to 1, the access technology can be selected, and if set to 0, the access technology cannot be selected. Similarly, sections 4.2.53 and 4.2.54 describe the EF content for the “Operator controlled PLMN selection with Access Technology” and “HPLMN selector with Access Technology” which also list the preferred PLMNs in priority order. Depending on which services are 2024PF00676

[0156] 26 16.12.2025 configured as “available” in the USIM, the UE uses one or more of said lists, in priority order, to perform PLMN and cell selection.

[0157] Thus, in an embodiment that may be combined with other embodiments or used independently, it may be therefore needed to map and / or filter and / or merge the PLMNs in the priority lists to their counterparts, if any, in the list of “PLMNs with associated RAT restrictions”. For instance, the list of “PLMNs with associated RAT restrictions” may be used by NAS layer to filter the PLMN / access technology combinations in the list of PLMNs with priority order configured for use, prior to triggering the AS layer to perform measurements for PLMN selection. This filtering may be triggered based on whether there is an overlap between PLMNs figuring in the list of priority order, and the ones included in the list of “PLMNs with associated RAT restrictions”, in case at least one PLMN figures in both lists, the UE may check the specific bits (e.g., b3, b4, b7, b8 in byte 5N-1) associated with said PLMN, and update the values within the priority list, as follows:

[0158] For each bit bx (e.g., b3 associated with satellite NG-RAN) that is set to “1”, the UE uses its counterpart by in the RAT utilization control information (e.g., b6 in octet 4 of Figure 9.9.3.3a. 1) to set bx = bx&by, where & is the bitwise AND operator, thus changing the status of restricted RATs in the priority list to “access technology cannot be selected”. Upon changing the status of RATs associated with PLMNs that figure in both the priority order and RAT restriction lists, the UE may re-prioritize the PLMNs in the priority order list based on its capability to select access technologies; for instance, if a PLMN is set to the highest priority and the access technologies associated with it are all restricted, the PLMN could not be selected and thus may be deprioritized, or skipped.

[0159] In an embodiment that may be combined with other embodiments or used independently, the function used to map and / or filter and / or merge the PLMNs in the priority lists to their counterparts may be configurable. For instance, next to above bitwise AND in above embodiment, other function such as “I”, i.e., bitwise OR operator may also be applicable. Such functions may be applicable to determine how to “merge” the priority and RAT restriction lists. The function or functions may be selected, e.g., based on policy. In some cases, the function may be such that one of the lists or some entries in one of the list is / are given priority, e.g., when enabling or disabling certain technologies.

[0160] In a variant of the embodiment, which may be combined with other embodiments or used independently, the mapping and / or filtering and / or merging of the list(s) of PLMNs with priority order may be performed at different stages in the interaction of the NAS and AS layers, e.g., based on configuration. This is illustrated by means of three scenarios depicted in Fig. 8.

[0161] In a first option, in scenario 800-a, the mapping and / or filtering and / or merging of the list(s) of PLMNs with priority order is performed in step 801, prior to NAS triggering AS layer to perform a search for available PLMNs in step 802, such that the request to AS may already include the filtered list of PLMNs in priority order, whereby the PLMN-RAT combinations available are filtered in step 803 at the AS layer, such that only non-restricted PLMNs and / or PLMNs with at least one non- 2024PF00676

[0162] 27 16.12.2025 restricted PLMN-RAT combination are reported back to NAS layer in step 804. The NAS layer may then determine which PLMN and / or PLMN / RAT combination the UE ought to access to the network through.

[0163] In an additional or alternative scenario 800-b, the NAS layer may request AS layer to perform the search for available PLMNs, in step 810, without indicating which PLMN-RAT combinations to exclude; while the AS layer performs PLMN search, the NAS layer may perform the mapping and / or fdtering of the list of PLMNs with priority order in step 811, such that upon receiving candidate PLMNs detected by the AS layer and reported (e.g., after a full search or upon NAS request to stop the search) in step 812, the NAS layer may filtering in step 813 the PLMN candidate list reported by AS layer using the updated priority order list resulting from step 811 and determine which PLMN and / or PLMN / RAT combination to access the network through, which is provided to the AS layer in step 814.

[0164] In another additional or alternative scenario 800-c, steps 820 and 821 are similar to the current PLMN selection procedure where NAS layer triggers in step 820 a search for PLMN candidates, and upon performing a full PLMN search or NAS request to stop the search, the AS layer reports in step 821, the candidate PLMNs detected. Once NAS layer received candidate PLMNs, it may check whether any of the candidate PLMNs figure in the list of “PLMNs with associated RAT restrictions”, and only if at least one candidate PLMN is present in said list, the UE (e.g., NAS layer) may perform mapping and / or filtering, in step 822, to determine the priority order of PLMNs, and / or eliminate from the list of candidate PLMNs the ones which figure in the list of “PLMNs with associated RAT restrictions”, if all radio access technologies are restricted and / or all RATs which said PLMN provides access through are restricted. In this case, the mapping / filtering to generate the updated priority list and the filtering of candidate PLMNs reported by AS are performed in the same step, and upon determining which PLMN and / or PLMN / RAT combination the UE ought to access the network through, the NAS layer provides it to the AS layer in step 823.

[0165] In a related embodiment, which may be combined with other embodiments or used independently, it is worth noting that the list of “PLMNs with associated RAT restrictions” may change frequently (e.g., new entries, updates to RAT restrictions, entries deleted, whole list removed), whereas priority lists (e.g., “User / Operator controlled PLMN selection with Access Technology” or “HPLMN selector with Access Technology”) may not change as frequently. Hence there is a need to check against the list of “PLMNs with associated RAT restrictions”, when available, and where there is overlap (i.e., PLMN figures in both priority order list and list of PLMNs with associated RAT restrictions), the UE may be configured to generate a transient / temporary priority list, wherein the status of access technologies (i.e., whether they can be selected or are restricted) is determined as described in other embodiments, e.g., the previous embodiment, and where the transient / temporary list is stored in the ME and / or the USIM. The transient list of priority order may be handled based on one, or more, or a combination of the following steps or actions: be removed right after a successful attach / registration to the network, 2024PF00676

[0166] 28 16.12.2025 be stored for as long as the lists of PLMNs priority order and “PLMNs with associated RAT restrictions” remain unchanged, be stored and maintained, if the list of “PLMNs with associated RAT restrictions” was removed due to USIM removal, be stored and updated when restrictions of at least a PLMN / RAT combination of a PLMN which figures in the list of “PLMNs with associated RAT restrictions” change, or a PLMN entry is deleted from the list, or a change of context e.g., a change in a list of Equivalent PLMNs associated with a PLMN whose restrictions applies to both the PLMN and its Equivalent PLMNs, which triggers the re- evaluation of the list of “PLMNs with associated RAT restrictions”; be stored according to an expiration time, and / or UE location, and / or conditions set / configured by the network operator.

[0167] In another embodiment , which may be combined with other embodiments or used independently, and with reference to Fig. 10, in phase 1001, the list of “PLMNs with associated RAT restrictions” (i.e., left list) which includes restrictions applicable to Equivalent PLMNs associated with (PLMNs 1, 5, and 6) may be mapped to the list(s) of PLMNs with priority order (i.e., right list(s)) (e.g., where there is overlap between PLMNs in both lists) to yield the transient list (i.e., list in the middle). Assuming, as in the previous embodiment, that the transient list is stored / maintained by the UE, the transient list may be updated based on changes to either one of the lists, hence in phase 1002, where the list of “PLMNs with associated RAT restrictions” is updated to exclude PLMN6 and include a new PLMN (i.e., PLMN7) along with associating it to its Equivalent PLMNs (i.e., according to the Type of RAT utilization control), the transient list may also be updated to reflect the changes to the list of “PLMNs with associated RAT restrictions”. It is worth noting that if a change in the list of Equivalent PLMN(s) associated with a PLMN whose restrictions are applicable to its Equivalent PLMNs occurs, that may be sufficient to check whether the transient list priority order is correct, or whether the transient list needs to be updated. Also, while the list of “PLMNs with associated RAT restrictions” may change more frequently, it is possible that the PLMN list(s) of priority order may also change. Hence, in phase 1003 where such a change occurs, while the UE maintains the transient list, it may be possible to use the old transient list, the new list of PLMNs with priority order, and the latest version of the list of “PLMNs with associated RAT restrictions” to generate a fresh updated list of priority order. Additionally, or alternatively, the transient list of priority order may at any point in time fallback to the configured list of PLMNs with priority order which is stored in the USIM and / or the UE, as indicated by the dotted arrow, e.g., in case the “PLMNs with associated RAT restrictions” is emptied / removed, or if the UE runs into conflicts, as described in other embodiments, which it could not resolve, or in case “PLMNs with associated RAT restrictions” no longer overlaps with the lists of PLMN(s) with priority order, etc.

[0168] In another embodiment, which may be combined with other embodiments or used independently, if the UE receives RAT utilization control information from a PLMN wherein all the RATs associated with, and supported by said PLMN are restricted (e.g., not all RATs may be restricted, 2024PF00676

[0169] 29 16.12.2025 but the subset of RATs restricted represents all RATs supported by the PLMN), the UE / ME may be configured to add said PLMN in the list of Forbidden PLMNs stored in the USIM’s EFFPLMN using the UPDATE command. Additionally, when the entry associated with said PLMN is removed (e.g., due to a PLMN update or USIM removal) from the list of “PLMNs with associated RAT restrictions”, the UE may be configured, depending on the removal cause, to delete (e.g., if the removal is due to PLMN updating RAT restrictions), or maintain (e.g., if the removal is due to USIM removal) the entry of said PLMN from the list of Forbidden PLMNs stored in EFFPLMN. The UE / ME has received an authorization to perform these updates, e.g., so that only updates related to entries of the RAT utilization control information are allowed. It is worth noting that in clause 4.2.16 of TS 31.102, it is described the mechanism by which EFFPLMN is updated; namely, the new (forbidden) PLMN is stored in the nth position of the list, and the existing list is shifted thus causing previous contents of the first position to be lost, unless there are less than “n” FPLMN entries in the EF.

[0170] Service-based exceptions to allow access through restricted PLMN / RAT combinations

[0171] Although access through PLMN / RAT combinations included in the list of “PLMNs with associated RAT restrictions” is restricted, there are an exception whereby the UE is allowed to access through said restricted PLMN / RAT combinations. Namely, when the UE tries to attach / register for emergency services. This, however, may be too limiting given the diverse service(s) that RATs may provide the UE with, especially in future releases and / or generations of wireless networks. Hence, in an embodiment, that may be combined with other (sub-)embodiments or used independently, the UE may be configured with a list of services (e.g., sensing as a service, energy as a service, computing as a service, etc) for which PLMN / RAT combination restrictions may or may not apply.

[0172] For instance, the list of “PLMNs with associated RAT restrictions” may be extended to included services that are allowed through said restricted PLMN / RAT combinations.

[0173] For instance, the UE and / or USIM may store a list of PLMNs with their respective services which may be exempt from PLMN / RAT combination restrictions.

[0174] For instance, the exemption from restrictions for selected services may be dependent on whether RAT cells can provide such service(s), which may be broadcast as part of system information (e.g., SIB1).

[0175] For instance, the exemption from restrictions for selected services may be location dependent; that is, the UE is exempt from restrictions only when it is served in a Tracking Area (TA) where said services are provided by the RAT, and the TA is configured as “whitelisted” at the UE (e.g., within “the PLMN list with associated RAT restrictions”).

[0176] For instance, the exemption from restrictions for selected services may be time dependent; that is, the UE is exempt from restrictions only when it is served in a particular period(s) of time where said services are provided by the RAT. 2024PF00676

[0177] 30 16.12.2025

[0178] For instance, the list of “PLMNs with associated RAT restrictions” may include combinations of two or more RATs that may be allowed / disallowed to be used together. For instance, a terrestrial network and a non-terrestrial network may only be used combined in a certain area. For instance, a non-terrestrial network may not be used in a certain area. For instance, a RAT network offering sensing services may be used together with a RAT offering communication services.

[0179] RAT utilization control information in HO procedures

[0180] In an embodiment related to the communication of RAT utilization control information, that may be combined with other (sub-)embodiments or used independently, in case a UE needs to be restricted from a radio access technology through which the UE is being served by the serving PLMN (SPLMN) and the UE is in connected state (i.e., CM-CONNECTED, RRC -CONNECTED), the network may trigger a deregistration procedure and include the RAT utilisation control information, in which the access technology, through which the UE is served UE, is restricted. Alternatively, the UE may receive the RAT utilization control information as part of a network triggered mobility procedure, whereby the serving PLMN may initiate a handover procedure aimed at pushing the UE towards access through a radio access technology that is not restricted, all the while minimizing disruption to UE’s connectivity to the network. Additionally or alternatively, the serving PLMN may, depending on the UE location, determine the radio access technologies that are not restricted and through which the UE could access network services, whereby conditions (e.g., RAT not restricted) may be provided to the UE, such that the UE may perform conditional HO (CHO) / DAPS HO / LTM considering the conditions on RAT restrictions equivalent to RAT utilisation control information. Furthermore, the UE may be configured to update its list of “PLMNs with associated RAT restrictions” based on RAT utilization control information received through a deregistration request, an RRC message triggering a Handover (HO) / DAPS HO procedure, or an RRC message containing information and / or conditions pertaining to a CHO / LTM procedure.

[0181] In a variant of the embodiment, that may be combined with other embodiments or used independently, the network may trigger the HO (HandOver) procedure to handover the UE from the current serving cell to the target serving cell of a restricted RAT, the UE may check whether the target serving cell is of the restricted RAT type of the current PLMN. Then, the UE may indicate to the current serving cell (source cell) that the HO is not successful and / or indicate the failure reason to the current serving cell, and the UE may further include the information related to “PLMNs with associated RAT restrictions” to the current serving cell.

[0182] In a variant of the embodiment, that may be combined with other embodiments or used independently, the HO procedure triggered by the network may rely on measurement reports sent by the UE to the network, whereby the UE initially receives a list of radio access technologies that are restricted and / or non-restricted and / or a specific RAT through which the UE may access the network. Then, the UE 2024PF00676

[0183] 31 16.12.2025 performs the requested measurements and report to the network measurements associated only with the radio access technology(ies) that are not restricted and / or the RAT type indicated by the network. The network may then determine the target cell(s) and / or candidate target cell(s), depending on the type of HO procedure to be performed, that the UE may access the network through. Upon successfully attaching / registering to the network through the indicated radio access technology, the UE may update the list of “PLMNs with associated RAT restrictions” to capture the potential changes to RAT restrictions associated with the serving PLMN. Alternatively, the UE may update the list of “PLMNs with associated RAT restrictions” based on the initial message received from the PLMN indicating the restricted / non- restricted RATs, regardless of whether the HO procedure succeeds or not. The UE may also be requested to perform measurements of certain restricted RATs, i.e., the UE may not be allowed to connect / use restricted RATs, but the UE may be requested to perform measurements of restricted RATs and / or send measurements of said restricted RATs. The conditions to perform the measurement transmission may also be configurable.

[0184] In a variant of the embodiment, that may be combined with other embodiments or used independently, the network may configure a list of candidate serving cells and one or more conditions to trigger CHO and / or LTM, the UE may check whether the candidate serving cell is of the restricted RAT types of the current PLMN. Then, the UE may only perform measurements and initiate handover on the candidate serving cells of the non-restricted RAT types when the condition(s) of handover meet(s). Additionally, the UE may provide the network the information related to “PLMNs with associated RAT restrictions” of the configured candidate serving cells. Additionally, the network may configure a new candidate serving cell list of the restricted RAT types removed.

[0185] In a variant of the embodiment, that may be combined with other embodiments or used independently, the CN may provide the network (e.g. base station) with the information related to “PLMNs with associated RAT restrictions” for a UE, so that the network may avoid those candidate serving cells when configuring the UE for HO measurement and CHO / LTM procedure. The network may also use this information to prevent a UE (without authorization / not allowed to use a RAT) from using a given RAT.

[0186] In a variant of the embodiment, that may be combined with other embodiments or used independently, a network function in the CN such as an access and mobility function may provide the network (e.g. base station) with the information related to “PLMNs with associated RAT restrictions” e.g., RAT utilization control information. This may be done using the following IE “Handover Restriction List” according to TS 36.413 V18.3.0 by adding a field of “Extended RAT Restriction Information”. This may complement, or override “RAT Restriction Information” in the previous releases of the specification, and include the information related to “PLMNs with associated RAT restrictions”, so that the network (e.g., base station) may use the information for selecting the target of the subsequent mobility action, such as HO, carrier redirection. 2024PF00676

[0187] 32 16.12.2025 2024PF00676

[0188] 33 16.12.2025 2024PF00676

[0189] 34 16.12.2025 2024PF00676

[0190] 16.12.2025

[0191] Extended RAT Restriction Information IE

[0192] This IE may include the different RATs that are restricted, e.g., LEO, MEO, GEO, etc satellites. In some cases, the restrictions applicable to RATs on-board satellites (e.g., LEO, MEO, GEO) may also depend on the operation mode, e.g., a LEO satellite operating in regenerative mode may be allowed but a LEO satellite operating in Store & Forward mode may not be allowed.

[0193] In another embodiment that may be combined with other embodiments or used independently, the “Handover Restriction List” according to TS 36.413 V18.3.0 and / or the “Mobility Restriction List” according to TS 38.413 V18.4.0, may be further extended to include the Type of RAT restrictions indicating the applicability of the restrictions i.e., whether the restrictions apply only to the serving PLMN (SPLMN), or to the SPLMN and its equivalent PLMNs (EPLMNs). In the former, the list of RAT restrictions in the Handover / Mobility restriction list may include the restrictions applicable to the serving PLMN, and restrictions, if any, applicable to each EPLMN separately as described in the current Handover / Mobility restriction list. In the latter, as the restrictions apply to both the SPLMN and its EPLMNs, the RAT restrictions may only include one entry of “RAT restriction information” / ”Extended RAT restriction information”, hence making the “PLMN identity” field indicating the identity of EPLMNs optional. Additionally, or alternatively, the type of RAT restrictions may be implicitly understood by the base station based on whether the RAT restrictions include a single or several entries, 2024PF00676

[0194] 36 16.12.2025 while the list of Equivalent PLMNs include many, i.e., if the list of EPLMNs includes several entries, while the RAT restrictions include only one entry of “RAT restriction information” or “Extended RAT restriction information”, it is implicitly understood that the restrictions are applicable to both SPLMN and its EPLMNs.

[0195] In another embodiment that may be combined with other embodiments or used independently, the UE may be allocated resources (e.g., frequency) to perform measurements associated with the restricted and / or non-restricted radio access technologies and / or resources to communicate said measurements to the network. For instance, the UE may be requested to perform measurements for restricted and / or non-restricted RATs associated with the PLMN, in a first and / or second frequency, respectively. Similarly, the UE may be allocated frequency resources to communicate its measurement reports associated with restricted and / or non-restricted RATs, in a third and / or fourth frequency, respectively.

[0196] RAT utilization control information in RRCRelease and / or RRCResume procedure

[0197] In an embodiment related to the communication of RAT utilization control information, that may be combined with other (sub-)embodiments or used independently, the network may trigger the RRC Connection Release procedure for the UE in RRC CONNECTED state, the RRCRelease message may include information related to “RAT utilization control information” as part of configuration for cell selection and / or reselection, and / or measurement / reporting related configuration in RRC IDLE / RRC INACTIVE state, the UE may update the list of “PLMNs with associated RAT restrictions” based on received information related to “RAT utilization control information”.

[0198] In a variant of the embodiment, that may be combined with other embodiments or used independently, the network may provide a serving cell of restricted RAT types in the redirectedCarrierlnfo IE, the UE may check the serving cell is of the restricted RAT types of the current PLMN. Then, UE may not perform cell selection and / or cell reselection of this configured serving cell. Additionally, the UE may provide the network the information related to “PLMNs with associated RAT restrictions” of the configured serving cell, so that the network may not redirect the UE to this serving cell later.

[0199] In another embodiment that may be combined with other embodiments or used independently, the network may trigger the RRC Connection Resume procedure for the UE in RRC INACTIVE state, the RRCResume message may include information related to “RAT utilization control information” as part of configuration for application layer measurement related configuration, the UE may update the list of “PLMNs with associated RAT restrictions” based on received information related to “RAT utilization control information”.

[0200] RAT utilization control information in cell (re-)selection 2024PF00676

[0201] 37 16.12.2025

[0202] In an embodiment that may be combined with other embodiments or used independently, a UE that is not connected may receive a message, e.g., a paging message to get connected to the network. However, the network may wish to control how the UE connects, e.g., in case that some RATs are currently less available for whatever reason. Thus, the message may include information about the list of “PLMNs with associated RAT restrictions” or RAT utilization control information. This information may be then used by the UE to perform the cell (re-)selection. This information may only be valid to the message itself, and may be removed afterwards (e.g., once the connection has been established and / or could not be established).

[0203] In an embodiment that may be combined with other embodiments or used independently, the list of “PLMNs with associated RAT restrictions” maintained in the NVM of the UE, may be used by NAS layer to trigger the AS layer(s) to perform cell search during cell (re-)selection procedures. For instance, following the PLMN selection procedure which takes into account the list of PLMNs in priority order and potentially the list of “PLMNs with associated RAT restrictions”, NAS layer may only trigger AS layer responsible for doing cell searches associated with RATs that are not restricted by the PLMN; for instance, PLMN 1 with associated RAT restrictions including NG-RAN and SAT-NG-RAN, may only instruct the EUTRAN AS layer to perform the cell search for e.g., cell selection procedure. Similarly, for the cell search / evaluation associated with cell reselection procedure, the NAS layer may only instruct the AS layer associated with non-restricted RATs to perform regular cell searches for a better cell. Note that while the change of cell following cell reselection may lead to a RAT change, the embodiment described herein ensures that in case of a RAT change, said RAT is not restricted by the PLMN in the UE configuration (i.e., list of “PLMNs with associated RAT restrictions).

[0204] In certain scenarios, following the NAS layer providing the AS layer with RAT utilization control information (e.g., List of “PLMN with associated RAT restrictions”), the AS layer may maintain a provided list of “PLMNs with associated RAT restrictions” for further use, e.g., for cell evaluation for the purpose of cell reselection. While the UE may receive further RAT utilization control information from a serving PLMN, thus impacting (e.g., by adding, updating, or deleting one or more entries) in the list of “PLMNs with associated RAT restrictions” stored in the UE, e.g., in the UE’s nonvolatile memory, the list of “PLMNs with associated RAT restrictions” may be updated on the NAS layer, whereas the AS layer may continue using an outdated list of “PLMNs with associated RAT restrictions”, which may impact a mobility procedure, e.g., the cell reselection procedure. It is therefore the aim of some of the following embodiments to address this issue, to that end:

[0205] In an embodiment that may be combined with other embodiments or used independently, upon the UE receives from a serving PLMN RAT utilization control information impacting (e.g., by adding, updating, or removing entry(ies) in the list of “PLMNs with associated RAT restrictions”) the list of “PLMNs with associated RAT restrictions”, the UE NAS layer may provide the updated list of “PLMNs with associated RAT restrictions” to the AS layer(s) performing cell evaluation for the purpose of cell reselection, thus ensuring the list of “PLMNs with associated RAT restrictions” maintained at both 2024PF00676

[0206] 38 16.12.2025 layers (i.e., NAS and AS) are synchronized. This action may be performed on immediately (e.g., as soon as the new list is received), or based on configuration (e.g., periodically, dependent on context, dependent on an action / change in NAS layer, etc).

[0207] In another embodiment that may be combined with other embodiments or used independently, to ensure procedures performed by the AS layer(s) (e.g., cell (re-)selection procedure) make use of the most up-to-date list of “PLMNs with associated RAT restrictions”, that is synchronized with the list of “PLMNs with associated RAT restrictions” maintained by the NAS layer and / or stored at the UE’s non-volatile memory, the AS layer(s) may request an update to the entry (i.e., RAT restrictions) associated with the serving PLMN (i.e., PLMN currently in use) or the entire list of “PLMNs with associated RAT restrictions” periodically (e.g., following a time period configured and / or provided by the network), or conditionally (e.g., following pre-defined conditions and / or triggered by an event), as configured by the network, following a triggering event which includes, but is not limited to, the following:

[0208] - performing a mobility (e.g., cell re-selection) procedure, or

[0209] - a change in the highest ranking cell according to cell reselection criteria, or

[0210] - a change in the best cell according to absolute priority reselection criteria, or

[0211] - a (back-off) timer (e.g., 300s) associated with not considering a candidate cell for cell reselection, as described in certain scenarios in 5.2.4.4 of TS 38.304 vl8.4.0, running out.

[0212] Following any of the (configured) events, the NAS layer may indicate whether the list / entries have been updated, and / or the NAS layer may provide the AS layer(s) with the updated entry (i.e., RAT restrictions) associated with the serving PLMN and / or the entire list of “PLMNs with associated RAT restrictions”.

[0213] In another embodiment that may be combined with other embodiments or used independently, the UE may receive from a serving PLMN RAT utilization control information impacting (e.g., by adding, updating, or removing entry(ies) in the list of “PLMNs with associated RAT restrictions”) the list of “PLMNs with associated RAT restrictions” in general, and the entry in the list of “PLMNs associated with RAT restrictions” associated with the current serving PLMN, in particular. Then, the UE NAS layer may instruct and / or restrict, according to the updated RAT restrictions associated with the current serving PLMN in the list of “PLMNs with associated RAT restrictions” the AS layer(s) to / from performing cell search / evaluation for the purpose of cell reselection. Additionally or alternatively, the AS layer(s) may periodically, or conditionally (as described in previous embodiments) request an update for the entry (i.e., RAT restrictions) associated with the current serving PLMN or the entire list of “PLMNs with associated RAT restrictions” thus ensuring only non-restricted AS layer(s) are performing cell search and evaluation for the purpose of cell reselection.

[0214] In another embodiment that may be combined with other embodiments or used independently, the request from AS layer(s) towards NAS layer associated with maintaining the lists of “PLMNs with associated RAT restrictions” may be a request for an update and / or a request for 2024PF00676

[0215] 39 16.12.2025 synchronization check (i.e., checking whether the list maintained by AS is valid still), to which the NAS layer may provide a response which acknowledges that the lists are in synch (e.g., if the list maintained by the AS layer(s) are valid still) or provides the updated entry (e.g., associated with the current serving PLMN) or the entire updated list of “PLMNs with associated RAT restrictions” (e.g., if the entry(ies) in the list maintained by the AS layer(s) is / are outdated) to the AS layer(s). Additionally, while the request may be from one AS layer (e.g., EUTRAN AS layer), depending on the potential changes to the RAT restrictions associated with the current serving PLMN, the response may trigger one or more AS layer(s), depending on which RATs are allowed / restricted. In another embodiment that may be combined with other embodiments or used independently, a list of “PLMNs with associated RAT restrictions” may be associated with an identifier that may allow identifying the PLMN and version, e.g., it may be, e.g., PLMN ID concatenated with date / time. This unique identifier may be used, e.g., to distinguish / determine whether the list available in the AS layer is outdated or not. For instance, the AS layer may provide the NAS layer with the identifier of the list that it currently stores, so that the NAS layer can verify whether the list is synchronized or not.

[0216] In some cases, a wireless device may comprise multiple radio access technologies (e.g., 2G, 3G, 4G, 5G). Some of these RAT have frozen stacks, and thus, it is not feasible to update the stack so that the list of “PLMNs with associated RAT restrictions” is taken into account directly in the RAT stack, in other words, that the NAS layer sends it to the corresponding AS layer. Thus, in another embodiment that may be combined with other embodiments or used independently, when the NAS layer receives the list of “PLMNs with associated RAT restrictions” and the NAS layer determines that some (legacy) RATs have restrictions in the current UE context, the NAS layer may (command to) fully disable the corresponding RAT technology when the NAS layer determines that the device is at a given location, or in general fulfils certain criteria.

[0217] In an embodiment that may be combined with other embodiments or used independently, a wireless device (UE) may indicate the RATs that it capable of and / or the user has enabled and / or the wireless device prefers. This may be indicated in the UE Capabilities. This may allow receiving a list of “PLMNs with associated RAT restrictions” that only contains information required for the wireless device reducing the communication overhead. If the wireless device activates certain RATs, the wireless device may send the indication to the PLMN so that the PLMN may provide the current list with restrictions.

[0218] Note that these embodiments may be advantageous to make sure that a wireless device / UE has the latest information available. Otherwise, if the wireless device only updates the list of “PLMNs with associated RAT restrictions” regularly, e.g., every 300 seconds, attackers may be feasible. Consider, e.g., an attacker that deploys a 4G fake base station and jams 5G cells forcing wireless devices to connect through the 4G cell. Even if the network (PLMN) distributes very rapidly an update of the list of “PLMNs with associated RAT restrictions”, many UEs would not take it into account. However, if 2024PF00676

[0219] 40 16.12.2025 wireless devices (UEs) are forced to check for an update of the list before performing a mobility procedure (e.g., cell re-selection), this problem is avoided.

[0220] It is to be further noted that in situations where UE has to wait a given time, e.g., 300s, before determining a cell is not “barred, if NAS provides AS with an updated list of PLMNs or with updated entry associated with current serving PLMN, which lifts the restrictions on said cell, AS layer may discard the running timer and consider the cell as a viable candidate for cell reselection. Similarly, if the updated (entry or list) happens to restrict a cell, e.g., the highest ranking cell, it is barred or deprioritized as it is now restricted.

[0221] In accordance with a general definition of this embodiment, it is proposed a method to ensure an entry to and / or the entire list of “PLMNs with associated RAT restrictions” maintained by the UE and / or NAS layer, and the entry to and / or the entire list of “PLMNs with associated RAT restrictions” maintained by AS layer(s) are synchronized, wherein the synchronization is performed: upon request from the AS layer(s), which may be performed periodically, or conditionally, and / or upon UE and / or NAS layer receiving an update to the list of “PLMNs with associated RAT restrictions” whereby the cell search and / or evaluation for cell (re-)selection is performed using an up- to-date list of “PLMNs with associated RAT restrictions”

[0222] It is further proposed a method by which, following a synchronization of the list of “PLMNs with associated RAT restrictions” between the UE and / or the NAS layer, and the AS layer(s) , one or more AS layer(s) are triggered to perform and / or are restricted from performing cell search and / or evaluation for cell reselection.

[0223] In another general definition, it is described a first method for selecting an access device comprising the steps of: receiving, by a UE, one or more access device selection configuration, storing, by the UE, the one or more access device selection configuration, and selecting, by the UE, one or more selected access devices based on the one or more access device selection configuration.

[0224] In another general definition, in the first method receiving, by a UE, one or more access device selection configuration may be received in the NAS layer.

[0225] Additionally, the selecting of the selected one or more access devices may comprise one or more of: the UE obtaining a second list comprising radio access technology utilisation control information from the one or more access device selection configuration received in the NAS layer; the UE determining a first list of configured Public Land Mobile Networks, PLMNs, / Radio Access Technology, RAT, with priority order stored in a Subscriber Identity Mobile such as a USIM or in a Mobile Equipment, ME, of the UE; 2024PF00676

[0226] 41 16.12.2025 the UE using the first list and the second list when performing or initiating PLMN and / or cell (re-)selection.

[0227] Additionally, the second list used by the UE when performing or initiating PLMN and / or cell (re-)selection may optionally be ensured to be up-to-date by one or more of:

[0228] - the AS layer requesting the NAS layer the most recently received second list upon the occurrence of an event; or

[0229] - the NAS layer sending the most recently received second list to the AS layer upon the occurrence of an event; wherein the event may be determined based on a configuration.

[0230] RAT utilization control information in measurement and reporting procedure

[0231] In an embodiment that may be combined with other embodiments or used independently, a UE that is in RRC IDLE / INACTIVE state performing measurement of current and / or neighbour serving cells may receive configuration from the network which may include information about the list of “PLMNs with associated RAT restrictions” or RAT utilization control information, the UE may use this information in determining which serving cells to monitor, and reporting the measurement results to the network; in an additional embodiment, the UE may determine the priority of the serving cells to monitor and reporting the measurement results to the network, in case there may be more than one serving cells to perform monitoring and measurement.

[0232] In a variant of the embodiment, that may be combined with other embodiments or used independently, the network may configure measurement and reporting configuration of serving cell associated with RATs that are, and / or are not, restricted, the UE may check whether the target serving cell is of the restricted RAT of the current PLMN. Then, the UE performs the requested measurements and report to the network measurements associated only with the radio access technology(ies) that are not restricted. Additionally, or alternatively, the UE may provide the information of the serving cell associated with restricted RAT type(s) to the network, so that the network knows the reason why measurement reports associated with said serving cell are not provided. Additionally or alternatively, the UE may receive from the network a new measurement and reporting configuration with serving cell of restricted RAT types removed (i.e., a configuration for measurement and reporting pertaining only to serving cells associated with non-restricted RAT types).

[0233] In a variant of the embodiment, that may be combined with other embodiments or used independently, the CN or the Serving PLMN may provide the (Radio Access) network (e.g. base station) with the information related to “PLMNs with associated RAT restrictions” for a UE, so that the network may avoid serving cells associated with restricted RATs when configuring the UE for measurement and reporting procedure. 2024PF00676

[0234] 42 16.12.2025

[0235] RAT utilization control information for L2 U2N Remote UE

[0236] In an embodiment that may be combined with other embodiments or used independently, an L2 U2N Remote UE may receive the “PLMNs with associated RAT restrictions” and / or RAT utilization control information from the network through the L2 U2N Relay UE. There may be situation that the RAT utilization control information may not allow the L2 U2N Remote UE to connect to the network through L2 U2N Relay UE, e.g. NG-RAN is not allowed according to RAT utilization control information of the current PLMN and / or equivalent PLMNs, in which case the L2 U2N Remote UE may deregister from the network.

[0237] In another embodiment, the L2 U2N Remote UE may use the saved “PLMNs with associated RAT restrictions” information in the NVM as part of the information in the ProSe discovery procedure to select the candidate L2 U2N Relay UE to connect to, e.g., based on the (H)PLMN ID broadcast in the discovery message(s) by the L2 U2N Relay UE, the L2 U2N Remote UE may determine, based on the list of “PLMNs with associated RAT restrictions” whether access through the U2N Relay UE is (or is not) restricted.

[0238] In another embodiment, the L2 U2N Relay UE may broadcast the “PLMNs with associated RAT restrictions” information in its ProSe discovery announcement message, and the L2 U2N Remote UE may use this information in determining the candidate L2 U2N Relay UE, e.g. matching the saved “PLMNs with associated RAT restrictions” in L2 U2N Remote UE with the broadcast “PLMNs with associated RAT restrictions” from the candidate L2 U2N Relay UE.

[0239] In another embodiment that may be combined with other embodiments or used independently, during the discovery procedure (e.g., with Model A or Model B), a L2 U2N Remote UE may receive in a discovery announcement message or a discovery response message information (e.g., PLMN ID) indicating the PLMN serving the L2 U2N Relay UE. The L2 U2N Remote UE may use the configured list of “PLMNs with associated RAT restrictions” to inform the U2N Remote UE’s selection of the L2 U2N Relay UE e.g., in both single or multi-hop scenarios. Note that the Remote UE may only require checking whether NG-RAN is or isn’t restricted for the U2N Relay UE’s PLMN. Additionally or alternatively, e.g., for future 3GPP releases where access through Relay UEs may be performed through other RATs, the U2N Relay UE may be required to provide an indication (e.g., in the discovery message) of the RAT through which the U2N Relay UE has access to the network; this indication may be used by the U2N Remote UE to determine whether access through U2N Relay UE would, or would not, be restricted, and hence determine whether to select said U2N Relay UE. Additionally or alternatively, the list of “PLMNs with associated RAT restrictions” may be extended to include indirect access (e.g., through a U2N Relay UE, or U2U Relay UE), such that an End UE (e.g., U2N Remote UE or U2U End UE) may only require the PLMN ID associated with the Relay UE (e.g., U2N Relay UE or U2U Relay UE) to determine whether it may select the Relay UE from which the discovery message was received. 2024PF00676

[0240] 43 16.12.2025

[0241] RAT utilization control information from an anchor carrier

[0242] In an embodiment that may be combined with other embodiments or used independently, the RAT utilization control information may be received by the UE from the network on an anchor carrier, e.g. in dual connectivity, or MRDC. Upon receiving such information and if the RAT utilization control information indicate that UE may be restricted from connecting to the network from a particular radio access technology, UE may need to disconnect from the network on that particular radio access technology.

[0243] In an embodiment that may be combined with other embodiments or used independently, the UE may be configured by the network to connect to a serving cell of another base station through dual connectivity, the UE may check whether the serving cell is of a restricted RAT type of the current PLMN. Then, the UE may indicate to the network the information related (e.g., from “PLMNs with associated RAT restrictions”) to the serving cell.

[0244] Resolution of potential conflicts in the list of “PLMNs with associated RAT restrictions”

[0245] In Figure 9.9.3.3a.1 of TS 23.122, the 2 -bit field “Type of RAT utilization control” may be used to indicate whether the RAT utilization control information (i.e., restrictions) are applicable to the PLMN, from which the RAT utilization control information was received, or applicable to that PLMN and its Equivalent PLMNs. As such, depending on the content of the list of “PLMNs with associated RAT restrictions” and potential new entries (i.e., RAT utilization control information associated with a serving PLMN), conflicts may arise and embodiments of this invention aim at addressing this need, embodiments, that may be used independently or combined with other embodiments. For instance, considering Fig. 9 where a UE registers at PLMN1 in step 901, and the list of “PLMNs with associated RAT restrictions” is populated with access technology restrictions associated with PLMN1 (e.g., in 901 or 901a) which has restrictions (e.g., 00000100, i.e., all restricted except E-UTRAN) that apply to both PLMN1 and its Equivalent PLMNs, which includes for instance PLMN3; Assuming the UE moves into another area, where it is served by PLMN2, upon attaching to PLMN2 in step 902, the UE may be provided with RAT utilization control information (e.g., 00010100, i.e., all restricted except E-UTRAN and Sat-E-UTRAN), wherein PLMN2 may indicate that the RAT utilization control information applies to both PLMN2 and its equivalent PLMNs, which includes for instance PLMN 1. In this case, the UE may detect that RAT utilisation control information provided to PLMN2 are also applicable to PLMN1 despite PLMN1 having already configured the UE with its RAT utilization control information. As such, the UE may indicate the conflict to PLMN2 in step 902a, which may be resolved by PLMN2 (e.g., by eliminating PLMN1 from the list of Equivalent PLMNs to PLMN2, or indicate which restrictions take precedence etc) and indicated to the UE in step 902b. Similarly, the UE moves to another area and attache s / register to PLMN3, wherein the UE is provided with PLMN3’s RAT utilization control information in step 903; the UE may detect that RAT utilisation control information provided by PLMN1 are also applicable to PLMN3, in which 2024PF00676

[0246] 44 16.12.2025 case, the UE may check for conflicts and request, in step 903a, from PLMN3 to resolve said conflict, if any; PLMN3 may then provide the UE with instructions on how to proceed and solve the conflict, ensuring that the list of “PLMNs with associated RAT restrictions” is conflict free. Given the potential for conflicts to arise, the UE and / or the network may be required to handle such conflict, and to that end:

[0247] In an embodiment aimed at addressing potential conflicts arising from two, or more sets, of non-equivalent radio access technology restrictions that are applicable to a PLMN, and that may be combined with other embodiments, or used independently, the UE may be configured to check, upon receiving RAT utilisation control information from a PLMN (e.g., through a NAS message), whether there is a potential conflict. For instance, the UE may check whether the PLMN identifier associated with the PLMN from which the RAT utilisation control information was received, regardless of whether the “Type of RAT utilisation control” in the received RAT utilisation control information indicates that restrictions apply only to that PLMN or to that PLMN and its Equivalent PLMNs, figures in the list of Equivalents PLMNs, of any of the PLMNs that are in the list of “PLMNs with associated RAT restrictions”, and for which the restrictions apply to both the PLMN and its Equivalent PLMNs. For instance, the UE may check, if the “Type of RAT utilization control” indicates that the RAT utilisation control information applies to both the PLMN and its Equivalent PLMNs, whether any of the PLMNs that figure in said list of Equivalent PLMNs is (or is not) already present in the list of “PLMNs with associated RAT restrictions”. Additionally, or alternatively the UE may, in case a PLMN is found in both the list of “PLMNs with associated RAT restrictions” and a list of Equivalent PLMNs of another PLMN that is also in the list of “PLMNs with associated RAT restriction”, determine whether there is a conflict between the RAT restrictions associated with the two entries, and whether to accept or reject the received RAT utilisation control information.

[0248] In a related embodiment, that may be combined with other (sub-)embodiments or used independently, the UE may be (pre-)configured e.g., by the network with a configuration and / or policy to manage potential conflicts that may arise, whereby the UE may for instance reject the received RAT utilisation control information, if a conflict is detected, and send a reject message indicating the rejection cause being due to a conflict (e.g., RAT utilisation control information conflict), or may be more specific, for instance the rejection cause value may indicate whether the PLMN providing the RAT utilisation control information figures as an Equivalent PLMN (e.g., of a PLMN that is in the list of “PLMNs with associated RAT restrictions”), or whether the Equivalent PLMNs (i.e., of the PLMN providing the RAT utilisation control information) include a PLMN that already has an entry in the list of “PLMNs with associated RAT restrictions”. Additionally, or alternatively, the UE may allow the received RAT utilisation control information, in case the RAT restrictions of the received and existing entries in the list of “PLMNs with associated RAT restrictions” are matching; for instance, a PLMN (e.g., PLMN1) provides RAT utilisation control information that are applicable to both PLMN 1 and its Equivalent PLMNs (e.g., including PLMN2, PLMN3, and PLMN5), if PLMN2 has an entry in the “PLMNs with associated RAT restrictions” and the restrictions associated with said entry are equivalent / match the RAT 2024PF00676

[0249] 45 16.12.2025 utilisation control information provided by PLMN1, the UE may accept the RAT utilisation control information from PLMN1; for instance, if PLMN5 figures as an Equivalent PLMN to PLMN4, which also has an entry in the list of “PLMNs with associated RAT restrictions”, and given that it is also in the list of Equivalent PLMNs of PLMN 1, then if the RAT utilisation control information of PLMN 1 and PLMN4 are equivalent / matching, then the UE may accept the received RAT utilisation control information from PLMN1, as no conflict is detected. Additionally, or alternatively, the UE may allow the received RAT utilisation control information and indicate to the UE the presence of a conflict and / or the potential for a conflict to arise in the future (e.g., in case any of the two sets of RAT utilisation control information that apply to a PLMN changes).

[0250] In another related mbodiment that may be combined with other embodiments of used independently, the UE may be configured with conditions and / or time counter set to trigger a check for whether the list of “PLMNs with associated RAT restrictions” has any conflicts or whether a conflict may arise due to change(s) to the list of PLMN / RAT combination restrictions or other lists associated with it (e.g., list(s) of Equivalent PLMNs); The UE may therefore be configured to trigger a check for conflicts upon one, or more, or a combination of the following conditions are met: receiving RAT utilisation control information associated with a new PLMN; receiving a RAT utilisation control information update associated with an entry in the list of “PLMNs with associated RAT restrictions”, which may change RAT restrictions associated with the PLMN from which the update was received, or change the “Type of RAT utilisation control” (i.e., change from applicable to PLMN only, to applicable to PLMN and its Equivalent PLMNs, or vice versa), or remove the entry associated with the PLMN from which the update was received from the list of “PLMNs with associated RAT restrictions”; an update to the list of Equivalent PLMNs associated with a PLMN that figures in the list of “PLMNs with associated RAT restrictions” with its “Type of RAT utilization control” being set such that the restrictions apply to the PLMN and its Equivalent PLMNs.

[0251] - a context change, e.g., (1) location change or (2) the usage of a new service (e.g., sensing service) or (3) time of the day / date, via a different RAT, that may change the RAT restrictions.

[0252] In another embodiment that may be combined with other embodiments or used independently, the UE may be configured to signal / indicate to the PLMN from which RAT utilisation control information was received, the presence of a conflict, and request assistance from said PLMN to resolve it. It is worth noting that this is particularly relevant in cases where the UE remains in a CONNECTED state (e.g., CM-CONNECTED) with the network, and thus may keep the RAT utilisation control information received on hold, while it (i.e., the UE) and the PLMN try to remediate / resolve the conflict detected. This may also be relevant in other states, e.g., IDLE or INACTIVE state. In case the UE requests assistance from its / a serving PLMN, the UE may receive as a response from the serving PLMN instructions and / or a configuration / policy determining how to resolve the conflict; for instance, the configuration and / or policy to manage / resolve the conflict may be based on a set of rules, which may be 2024PF00676

[0253] 46 16.12.2025 provided to the UE on-demand (e.g., upon conflict detection / reporting), or pre-configured by the network, in which case the request for assistance may only be required if the resolution fails based on the configured set of rules in the UE. This set of rules may determine an order of prioritization and / or an action to be performed by the UE, which enables it to determine the RAT utilisation control information applicable to one or PLMN(s) in the list of “PLMNs with associated RAT restrictions”. For instance, the set of rules (pre-)configured at the UE may include, but is not limited to, one, or more of the following: prioritizing RAT utilisation control information associated with a PLMN (e.g., PLMNi) over RAT control information that apply to another PLMN (e.g., PLMN2) that has PLMNi as an Equivalent PLMN. prioritizing the most recently received RAT utilisation control information, regardless of whether it is associated with the PLMN (e.g., PLMNi) itself, or inherited from another PLMN (e.g., PLMN2) that has PLMNi as an Equivalent PLMN. removing from the list of Equivalent PLMNs associated with the PLMN from which the RAT utilisation control information was received, all PLMN(s) for which an entry in the list of “PLMNs with associated RAT restrictions” exist and all PLMN(s) that figure in the list of Equivalent PLMNs of another PLMN that figures in the list of “PLMNs with associated RAT restrictions” and whose Type of RAT utilisation control is set to be applicable to both said PLMN and its Equivalent PLMNs, removing the PLMN from which the RAT utilisation control information was received from any list of Equivalent PLMNs associated with any PLMN that has an entry in the list of “PLMNs with associated RAT restrictions”, in case the UE fails to resolve the conflict locally, the UE may request assistance from the network, whereby the UE indicates the conflicts it could not resolve.

[0254] It is worth noting that some rules, e.g., third and fourth, may be conditional on whether the “Type of RAT restrictions” received in the RAT utilisation control information indicates that the restrictions apply to both the PLMN and its Equivalent PLMNs.

[0255] In another embodiment that may be combined with other embodiments or used independently, the UE may be configured to request assistance from the network to resolve detected conflicts as follows:

[0256] In a first step, the UE may receive from the serving PLMN RAT utilisation control information pertaining to said PLMN, and potentially its Equivalent PLMNs, if so indicated.

[0257] In a second step, and assuming the UE has detected a conflict with one, or more, entrie(s) in its list of “PLMNs with associated RAT restrictions”, where the conflict is of any type that is described in previous embodiments, the UE may, depending on its configuration, attempt to request assistance from the network, or attempt to resolve the conflict and only request network assistance in case of failure to resolve the conflict locally. The UE may send a request for assistance to the network which includes details about the conflict detected, e.g., PLMNs and RATs concerned, type / identifier of the conflict, rules and / or policy / configuration identifier applied to attempt to resolve the conflict locally, etc. 2024PF00676

[0258] 47 16.12.2025

[0259] In a third step, the serving PLMN may, depending on whether sufficient information was provided by the UE to resolve the conflict was provided, provide the UE with a set of instructions to resolve the conflict, or request the UE to provide supplementary information related to the conflict, which the UE e.g., may not have provided in the previous step.

[0260] In a fourth step, upon receiving a response from the serving PLMN, the UE may try to resolve the conflict based on the set of instructions provided by the serving PLMN, in which case, depending on whether the conflict is resolved successfully, or not, the UE sends an acknowledgement message to confirm the conflict was resolved successfully, or an error / failure message indicating that the conflict was not resolved. Alternatively, if the UE receives a request for supplementary information from the serving PLMN, the UE may provide such information, in which case the UE can expect the network to subsequently provide instructions to resolve the conflict.

[0261] It is worth noting that the steps described above, especially the third and fourth steps may be repeated, and / or omitted, and / or organized differently, depending on the conflict detected, whether the UE manages to resolve it locally, and / or whether more (supplementary) information is requested by the network to resolve the detected conflict. It is worth noting that in some cases a conflict may be caused and / or a configuration may be provided that may prevent a UE from accessing services, e.g., if all RATs had restrictions. In such cases, in a related embodiment that may be combined with other embodiments or used independently, a UE may be configured to request assistance from the network, whereby the UE indicates the conflicts it could not resolve and / or its status. This may require accessing the network using one of the restricted RATs.

[0262] In summary, this invention discloses a method for access device selection implemented in a wireless device by means of a computer program, the method comprising the following steps: receiving, by the wireless device, one or more access device selection configurations, storing, by the wireless device, the one or more access device selection configurations, and selecting, by the wireless device, one or more access devices based on the one or more access device selection configurations.

[0263] Section: updating access technology utilisation control / access device selection configuration

[0264] In certain scenarios, the handling of the list of PLMNs with associated access technology restrictions may be as follows: upon receiving an access technology utilization control information from a registered / serving PLMN, the UE may replace previously stored entries associated with the current (i.e., registered / serving) PLMN, if any, with the newly received access technology utilisation control information in some cases. More specifically, (case 1) if the type of access technology utilization control indicates “current PLMN and its equivalent PLMN(s)”, the UE deletes all previously stored entries associated with PLMNs included in the list of equivalent PLMNs, excluding the entry associated with the 2024PF00676

[0265] 48 16.12.2025 current PLMN. Additionally, (case 2) if the type of access technology utilization control indicates “current PLMN”, the UE deletes all previously stored entries associated with PLMNs included in the list of equivalent PLMNs and indicating “current PLMN and its equivalent PLMNs”. However, the handling described for case 1 and case 2 may not be sufficient to prevent conflicts, as previously described, or may impact access technology utilization control configurations belonging to other PLMNs.

[0266] In a first problem related to case 1, assuming the list of “PLMNs with associated access technology restrictions” stored in the UE (i.e., ME) includes the following entries as an example:

[0267] PLMN i : current PLMN,

[0268] PLMNs: current PLMN and equivalent PLMNs, equivalent PLMNs={PLMN4}, and

[0269] PLMNe: current PLMN and equivalent PLMNs, equivalent PLMNs={PLMN5, PLMN?}.

[0270] The UE receives access technology utilization control information PLMNi as follows: PLMNi: current PLMN and equivalent PLMNs, List of EPLMNs = {PLMN2, PLMNs, PLMNs}.

[0271] Considering that entries associated with PLMNs included in the list of EPLMNs (Equivalent PLMNs i.e., PLMNs in this case) need to be deleted, the updated list of “PLMNs with associated access technology restrictions” stored in the UE (i.e., ME) becomes in this example:

[0272] PLMNi, current PLMN and equivalent PLMNs, List of EPLMNs = {PLMN2, PLMNs, PLMNs}.

[0273] PLMNe: current PLMN and equivalent PLMNs, equivalent PLMNs={PLMN5, PLMN?}.

[0274] Since PLMNs figures in both lists of equivalent PLMNs corresponding to PLMNi and PLMNe, access technology utilization control information associated with the two PLMNs (i.e., PLMNi and PLMNe), which may be different, are both applicable to PLMNs, hence the conflict. It is an aim of an embodiment of this invention to avoid such conflicts.

[0275] Thus, in an embodiment that may be combined with other embodiments or used independently, the UE may cross check or compare the lists of equivalent PLMNs pertaining to the current PLMN (i.e., received), against the lists of equivalent PLMNs associated with all entries in the list of “PLMNs with associated access technology restrictions” and delete any PLMN entry where an overlap between the lists of equivalent PLMNs is detected. This allows maintaining only the latest access utilization control information and avoiding potential conflicts.

[0276] Additionally, or alternatively, the UE may be configured to maintain both entries and prioritize inheriting access technology restrictions from the entry added last to the list of “PLMNs with associated access technology restrictions”. This allows maintaining access technology restrictions applicable to the impacted PLMN (i.e., PLMNe in the previous example) and its equivalent PLMNs that do not figure in the list of equivalent PLMNs of the current PLMN (i.e., PLMNi in the example).

[0277] Additionally or alternatively, the UE may be configured e.g., by one or more previous PLMNs (i.e., when providing access utilization control configurations), or current PLMN, to delete PLMN(s) from the list of equivalent PLMNs (e.g., PLMNs) in case a conflict is detected, as described in 2024PF00676

[0278] 49 16.12.2025 previous embodiments. For instance, if PLMNe has configured the UE to act accordingly, upon receiving the access technology utilization control information from PLMNi, the UE may delete PLMNs from the list of equivalent PLMNs of PLMNe. For instance, if UE has not been configured accordingly by PLMNe, but was configured as such by current PLMN (i.e., PLMNi), the UE may delete PLMNe from the list of equivalent PLMNs of PLMNi. For instance, if the UE was neither configured by PLMNe, nor by PLMNi, the UE may default to one of the previously described behaviours e.g., to maintain both and prioritize the latest configuration received, or delete the entry(ies) whose lists of equivalent PLMNs overlap with the list of equivalent PLMNs of the current PLMN.

[0279] In a second problem related to case 2, where a UE deletes all previously stored entries associated with PLMNs included in the list of equivalent PLMNs and indicating “current PLMN and its equivalent PLMNs”, there may be significant impact on access technology utilization control information provided by the other PLMNs. For instance, if one considers the following example where the list of “PLMNs with associated access technology restrictions” stored in the UE (i.e., ME) includes the following entries:

[0280] PLMN2, current PLMN and Equivalent PLMNs, List of EPLMNs = {PLMN5, PLMNe}. PLMNs current PLMN and Equivalent PLMNs, List of EPLMNs = {PLMNi } .

[0281] PLMN4: current PLMN and Equivalent PLMNs, List of EPLMNs = {PLMN?} . PLMNs current PLMN and Equivalent PLMNs, List of EPLMNs = {PLMNi } . The UE receives access technology utilization control information from PLMNi as follows:

[0282] PLMNi: current PLMN, and a list of EPLMNs = {PLMN2, PLMNs}.

[0283] Considering that entries associated with PLMNs included in the list of EPLMNs (i.e., PLMN2, and PLMNs) need to be deleted, the updated list of “PLMNs with associated access technology restrictions” stored in the UE (i.e., ME) becomes:

[0284] PLMNi, current PLMN, List of EPLMNs = {PLMN2, PLMNs}.

[0285] PLMN4: current PLMN and Equivalent PLMNs, List of EPLMNs = {PLMN?} . PLMNs current PLMN and Equivalent PLMNs, List of EPLMNs = {PLMNi } . As the access technology restrictions associated with PLMNi are applicable only to “current PLMN”, the PLMNs (i.e., PLMN2 and PLMNs) included in the list of EPLMNs do not inherit the restrictions associated with PLMNi and are as such not impacted. However, the deletion of the entries associated with these PLMNs (i.e., PLMN2 in this case) may impact the restrictions configured by said PLMN. This may result for example in

[0286] - the loss of valid restrictions (i.e., access technology restrictions configured by PLMN2 and applicable to it and to its EPLMNs (i.e., PLMNs and PLMNe) are discarded and as such lost),

[0287] - violation of independence between configurations of different PLMNs (e.g., deletion of the access technology configuration of PLMN2 undermines PLMN2 ability to enforce its intended configuration), 2024PF00676

[0288] 50 16.12.2025 unintended UE behaviour (e.g., due to the deletion of the entry associated with PLMN2, UE may attempt access to PLMN2 (or an EPLMN thereof), through an access technology that is restricted according to PLMN2.

[0289] By contrast, the deletion of the entry associated with PLMN3 may be less impactful, since PLMNi is included in the EPLMNs of PLMN3, and hence the deletion of the entry associated with PLMN3 does prevent a conflict from arising, although its deletion may have similar effects as the deletion of PLMN2. PLMNs, whose restrictions are also applicable to PLMNi, remain unimpacted, although its presence may give rise to a conflict.

[0290] Thus, in an embodiment that may be combined with other embodiments or used independently, which is aimed at addressing the aforementioned issues, the UE may be configured to delete entries in the list of “PLMNs with associated access technology restrictions” only if the restrictions are also applicable to the equivalent PLMNs (i.e., type of access technology utilization control is set to “current PLMN and equivalent PLMNs”.

[0291] Additionally, or alternatively, when receiving access technology utilization control information with a type indicating “current PLMN”, the UE may check whether the current / serving PLMN (i.e., PLMN from which the access technology utilization control information are received) figures in any list of EPLMNs associated with the PLMN entries in the list of “PLMNs with associated access technology restrictions” that are applicable to “current PLMN and equivalent PLMNs”. The UE may determine based on a policy / configuration e.g. provided by the PLMN associated with the existing entry, whether to delete the current PLMN from its list of EPLMNs, or maintain both entries and prioritize the access technology restrictions received from the current PLMN, as described in previous embodiments, or delete the entry associated with said PLMN (e.g., PLMNs in the aforementioned example) regardless of whether it is, or is not, included in the list of equivalent PLMNs of the current PLMN.

[0292] Additionally, or alternatively, in an embodiment that may be combined with other embodiments or used independently and may be applicable to case 1 and case 2, instead of deleting the entries, existing entries may be set to an “inactive state” meaning that they are not active since the wireless device / UE is not currently in the PLMN. This allows the wireless device to reactivate those entries as soon as the wireless device moves back to the corresponding PLMN, or if (active) conflicting entries are deleted from the list of “PLMNs with associated access technology restrictions”. Furthermore, PLMNs included in more than one list of Equivalent PLMNs stored in the UE may be associated with an identifier indicating the PLMN, whose access technology restrictions can be activated and / or used. Furthermore, each entry may include a context (e.g., time, location, PLMN,... ) in which the entry may be activated / used or not. It is to be noted that setting some entries to an “inactive state” is (somehow) equivalent to prioritizing other entries that are not in an “inactive state”. It is to be noted that the state of some entries may change (e.g. triggered by the UE / wireless device and / or triggered by the network) when 2024PF00676

[0293] 51 16.12.2025 the wireless device roams, e.g., when the wireless device registers in a new serving network. This allows the wireless device to use the right entries without requiring receiving a configuration. a. In general it is described a method for selecting an access device by managing a list of “PLMNs with associated access technology restrictions” comprising the steps of: receiving, by a UE, one or more access device selection configuration, b. storing, by the UE, the one or more access device selection configuration, and c. selecting, by the UE, one or more selected access devices based on the one or more access device selection configuration.

[0294] In general it is described a method for managing a list “PLMNs with associated access technology restrictions” for conflict avoidance, wherein the method comprises the steps of receiving, by a UE, one or more access device selection configuration, and storing, by the UE, the one or more access device selection configuration. In more detail, the method may comprise: receiving, by a wireless device, an access technology utilization control configuration from a PLMN, with type “current PLMN and equivalent PLMNs”, and a list of equivalent PLMNs, optionally determining, by the wireless device, whether there is an overlap between the received list of equivalent PLMNs and any list of equivalent PLMNs associated with any existing entry in the list of “PLMNs with associated access technology restrictions”, and performing, by the wireless device, one of the following: o deleting from the list of “PLMNs with associated access technology restrictions” the entry associated with the list of equivalent PLMNs overlapping with the received list of equivalent PLMNs, o removing from the received list of equivalent PLMNs the PLMN(s) overlapping with the at least list of equivalent PLMNs stored at the UE, o removing from at least the list of equivalent PLMNs, stored at the UE, the PLMN(s) overlapping with the received list of equivalent PLMNs, o maintaining the at least overlapping two lists of equivalent PLMNs and prioritizing the access technology utilization control configuration received last, or o setting one of the entries in the list as active and another entry as inactive.

[0295] In general it is described a method for managing a list of “PLMNs with associated access technology restrictions” for conflict avoidance, wherein the method comprises: receiving, by the wireless device, an access technology utilization control configuration from a PLMN, with type “current PLMN”, and a list of equivalent PLMNs, optionally determining, by the wireless device, whether any list of equivalent PLMNs associated with any entry in the list of “PLMNs with associated access technology restrictions”, whose type indicates “current PLMN and equivalent PLMNs” includes the PLMN identity of with the serving PLMN from which the access technology utilization control configuration was received, 2024PF00676

[0296] 52 16.12.2025 performing, by the wireless device, (optionally upon detecting the presence of the serving PLMN identity in the list of equivalent PLMNs associated with at least one entry in the list of “PLMNs with associated access technology restrictions”), one or more of the following: o deleting the at least one entry, whose list of equivalent PLMNs includes the PLMN identity of the serving PLMN, from the list of “PLMNs with associated access technology restrictions”, o removing the PLMN identity associated with the serving PLMN, from the at least one list of equivalent PLMNs which includes it, o maintaining the at least one entry, whose list of equivalent PLMNs includes the PLMN identity of the serving PLMN, in the list of “PLMNs with associated access technology restrictions” together with the entry of the serving PLMN and prioritizing the access technology utilization control configuration associated with the serving PLMN, and o setting one of the entries in the list as active and another entry as inactive.

[0297] Furthermore, this invention can be applied to various types of UEs or terminal devices, such as mobile phone, vital signs monitoring / telemetry devices, smartwatches, detectors, vehicles (for vehicle-to-vehicle (V2V) communication or more general vehicle-to-everything (V2X) communication), V2X devices, Internet of Things (loT) hubs, loT devices, including low-power medical sensors for health monitoring, medical (emergency) diagnosis and treatment devices, for hospital use or first-responder use, virtual reality (VR) headsets, etc.

[0298] Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure and the appended claims. In the claims, the word “comprising” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude a plurality. A single processor or other unit may fulfil the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. The foregoing de-scription details certain embodiments of the invention. It will be appreciated, however, that no matter how detailed the foregoing appears in the text, the invention may be practiced in many ways, and is therefore not limited to the embodiments disclosed. It should be noted that the use of particular terminology when describing certain features or aspects of the invention should not be taken to imply that the terminology is being re-defined herein to be restricted to include any specific characteristics of the features or aspects of the invention with which that terminology is associated. Additionally, the expression “at least one of A, B, and C” is to be understood as disjunctive, i.e., as “A and / or B and / or C”. The same applies to the expressions “A or B” and “at least one of A or B”, i.e., they may indicate all possible combinations of the listed items.

[0299] A single unit or device may fulfil the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. 2024PF00676

[0300] 53 16.12.2025

[0301] The described operations like those indicated in the above embodiments may be implemented as program code means of a computer program and / or as dedicated hardware of the related network device or function, respectively. The computer program may be stored and / or distributed on a suitable medium, such as an optical storage medium or a solid-state medium, supplied together with or as part of other hardware, but may also be distributed in other forms, such as via the Internet or other wired or wireless telecommunication systems.

Claims

1. 2024PF0067616.12.2025CLAIMS:

1. A method for (re-) selecting an access device comprising the steps of:- receiving, by a user equipment, UE, a list of radio access technology utilization control information configuration,- storing, by the UE, the list of radio access technology utilization control information configuration,- providing, by a first stack layer of the UE, to a second stack layer of the UE, the list of radio access technology utilization control information configuration,- determining or obtaining, based on measurement performed by the second stack layer of the UE, a second list of prioritized candidate access technologies,- updating, by the UE, the second list of prioritized candidate access technologies based on the list of radio access technology utilization control information configuration, and- performing, by the UE, cell (re-)selection based on the updated second list of prioritized candidate access technologies.

2. A method for selecting an access device comprising the steps of: receiving, by a user equipment, UE, a first list of first radio access technology utilization control information configuration, storing, by the UE, the first list of first radio access technology utilization control information configuration, obtaining, by the UE, a second list of second radio access technology utilization control information configuration from a serving Public Land Mobile Networks, PLMN, to which the UE is connected, wherein the second list of second radio access device selection configuration comprises restrictions on the radio access technology currently in use by the UE, updating, by the UE, the first list based on the second list; and performing or initiating, by the UE, PLMN and / or cell (re-)selection based on the updated first list.

3. The method of claim 2, wherein the first list or the second list comprise a list of configured PLMNs, Radio Access Technology, RAT, with priority order stored in a Subscriber Identity Mobile such as a USIM or in a Mobile Equipment, ME, of the UE.2024PF0067655 16.12.20254. The method of claim 2 or 3, wherein (i) the first list comprises a list of PLMNs with associated RAT restrictions and (ii) the first list comprises one or more of the following:- Home Public Land Mobile Network, HPLMN, Selector with Access Technology;- User Controlled PLMN Selection with Access Technology;- Operator Controlled PLMN Selection with Access Technology.

5. The method of any of claims 2 to 4, wherein the updating of the first list comprises removing, and / or changing the priority order, of PLMNs / radio access technologies in the first list based on the PLMNs / radio access technologies combination restrictions in the second list.

6. The method of any of claims 2 to 5, wherein the updating step comprises: storing in the ME, or the USIM a third list comprising the updated priority order list of the candidate PLMNs for PLMN / cell selection procedure(s), performing PLMN and / or cell selection based on the third list.

7. The method of claim 6, wherein the third list is stored in the non-volatile memory of the UE, and the method further comprises performing, by the UE, one or more of: removing the third list from the non-volatile memory after a successful attach / registration procedure to a network; updating the third list based on a change to entries in the first list and / or the second list of restrictions; updating the third list based on context change triggering a re-evaluation of the second list restrictions; keeping the third list stored in the UE depending on one or more of the following conditions: both the first list of priority order and the second list of restrictions remain unchanged; or the first list of priority order remains unchanged, and the second list of PLMN / access technology combination restrictions is deleted due to USIM removal; or the third list remains valid according to the context comprising one or more of: an expiration time and / or location and / or conditions configured by the network.

8. The method of any of claims 5 to 7, wherein the updating of the priority order in the first list using the second list is performed based on one of: prior to NAS layer triggering the search for candidate PLMNs, whereby:2024PF0067656 16.12.2025- the first and the second list, or a combination thereof, comprising the updated priority order, is communicated to the AS layer to filter candidate PLMNs to be reported back to NAS layer, or- the first and the second list, or a combination thereof, comprising the updated priority order, is used by NAS layer to filter candidate PLMNs reported by AS layer upon performing a search for PLMNs. while the AS layer is performing the search for candidate PLMNs, whereby the candidate PLMNs are filtered based on the first and second list, or a combination thereof, comprising the updated priority order; after receiving the candidate PLMNs from the AS layer, and there being an overlap between PLMNs in the list of PLMNs with associated RAT restrictions and the candidate PLMNs.

9. The method of claim 1, wherein if the first list of first radio access technology utilization control information configuration received restricts some or all access technologies for one or more determined PLMN(s), the determined PLMN subject to such restrictions is added to a list of Forbidden PLMNs stored in the USIM.

10. The method of claim 1 or 9, wherein the access device selection configuration comprises indication of non-emergency services that the UE is allowed to receive through restricted PLMN / radio access technology combinations.

11. The method of claim 1, wherein the access device selection configuration is received by the UE through a DEREGISTRATION REQUEST message from the network.

12. The method of any of the previous claims 1 to 11, comprising the UE reporting to the network measurements pertaining to radio access technologies that are not restricted and / or restricted according to the access device selection configuration provided by the network and / or services required by the UE.

13. The method of claim 12, comprising: the UE performing network measurements pertaining to radio access technologies that are not restricted with a first frequency and / or network measurements pertaining to radio access technologies that are restricted are performed with a second frequency; and / or the UE reporting of network measurements pertaining to radio access technologies that are not restricted are performed with a third frequency and / or reporting of network measurements pertaining to radio access technologies that are restricted are performed with a fourth frequency.2024PF0067657 16.12.202514. The method of claim 1, comprising the UE checking for conflicts upon receiving one or more access device selection configurations; and wherein each access device selection configuration comprises: the PLMN subject to restrictions and radio access technology(ies) that are (or are not) restricted in the PLMN, and“Type of RAT utilisation control” indicating whether the restrictions are of a first type: applicable to the PLMN only, or of a second type: applicable to the PLMN and its Equivalent PLMNs.

15. The method of claim 14, wherein the UE checking for conflicts in the one or more access device selection configuration(s) comprises the UE performing one or more of the following:If the “Type of RAT utilisation control” in the received access device selection configuration is of the first type: checking, for any second PLMN in the list of "PLMNs with associated RAT restrictions" where the “Type of RAT utilisation control” is of the second type, whether the list of Equivalent PLMNs of the one or more second PLMN(s), if any, contains the first PLMN identifier; or If the “Type of RAT utilisation control” in the received access device selection configuration is of the second type: checking whether the identifier of any second PLMN in the list of "PLMNs with associated RAT restrictions" is present in the list of Equivalent PLMNs associated with the first PLMN; and / or checking, for any second PLMN in the list of "PLMNs with associated RAT restrictions" where the “Type of RAT utilisation control” is of the second type, whether the identifier of any third PLMN in list of Equivalent PLMNs to the second PLMN, is present in the list of Equivalent PLMNs associated with the first PLMN; and the method comprising the UE determining whether to accept or reject the received access device selection configuration.

16. The method of claim 14 or 15, wherein the UE is (pre-)configured by the network with a configuration for conflict resolution, wherein the configuration comprises one or more of the following steps: rejecting the received access device selection configuration and sending a reject message indicating the rejection cause; accepting the received access device selection configuration from the first PLMN if, and only if:2024PF0067658 16.12.2025 restrictions applicable to the first PLMN and its associated radio access technologies match the radio access technology restrictions applicable to, and inherited from, the second PLMN whose list of Equivalent PLMNs includes the first PLMN identifier; and / or the “Type of RAT utilisation control” in the received access device selection configuration associated with the first PLMN is of the second type, and: radio access technology restrictions applicable to any second PLMN in the list of “PLMNs with associated RAT restrictions” that is present in the list of Equivalent PLMNs of the first PLMN match the restrictions in the received access device selection configuration; and / or radio access technology restrictions applicable to any third PLMN in the list of Equivalent PLMNs associated to any second PLMN in the list of “PLMNs with associated RAT restrictions” whose “Type of RAT utilisation control” is of the second type, match the restrictions in the received access device selection configuration and the list of Equivalent PLMNs associated with the first PLMN includes the third PLMN; accepting or keeping the received access device selection configuration on hold upon detecting a conflict and: managing / resolving the conflict locally; and / or requesting the network to resolve the conflict and receiving network feedback; whereby the UE determines whether to accept / update / reject the received access device selection configuration based on the outcome of conflict resolution; or conditions and / or a time counter set to trigger a check for conflicts within the list of “PLMNs with associated RAT restrictions”.

17. The method of claim 16, wherein the conditions to trigger a check for conflicts within the list of “PLMNs with associated RAT restrictions” comprise at least one of: receiving an access device selection configuration associated with a new PLMN; or receiving an updated access device selection configuration associated with a PLMN that is present in the list of “PLMNs with associated RAT restrictions”, wherein the update comprises: a change to the PLMN / radio access technology combination restrictions; a change to the “Type of RAT utilisation control”; removal of an access device selection configuration; or receiving an update impacting the list of Equivalent PLMNs associated with any PLMN included in the list of “PLMNs with associated RAT restrictions” whose “Type of RAT utilisation control” is of the second type; or a change of context which includes location change and / or a change of service(s).2024PF0067659 16.12.202518. The method of any of claims 14 to 17, wherein the configuration and / or policy for conflict resolution further comprises a process to manage potential conflicts locally, whereby the UE is configured to perform one or a combination of the following: prioritizing the restrictions in the access device selection configuration associated with the first PLMN over restrictions inherited from the access device selection configuration associated with any second PLMN whose list of Equivalent PLMNs contains the first PLMN; or prioritizing the most recent access device selection configuration applicable to the first PLMN, regardless of whether the access device selection configuration is associated with the first PLMN, or is inherited from any second PLMN whose list of Equivalent PLMNs contains the first PLMN; or if the “Type of RAT utilisation control” in the received access device selection configuration is of the first type: removing any occurrence of the first PLMN identifier in the list(s) of Equivalent PLMNs associated with any second PLMN included in the list of “PLMNs with associated RAT restrictions”, whose “Type of RAT utilisation control” is of the second type, before adding the access device selection configuration associated with the first PLMN of “PLMNs with associated RAT restrictions”; or if the “Type of RAT utilisation control” in the received access device selection configuration is of the second type: removing from the list of Equivalent PLMNs associated with the first PLMN any PLMN identifier that is associated with an entry in the list of “PLMNs with associated RAT restrictions”, before adding the access device selection configuration associated with the first PLMN and its Equivalent PLMNs to the list of “PLMNs with associated RAT restrictions”; removing the PLMN identifier associated with any third PLMN that is present in the list of Equivalent PLMNs associated with the first PLMN and the list of Equivalent PLMNs associated with any second PLMN in the list of “PLMNs with associated RAT restrictions” from either list(s) of Equivalent PLMNs, before adding the access device selection configuration associated with the first PLMN and its Equivalent PLMNs to the list of “PLMNs with associated RAT restrictions”.

19. The method of claim 18, comprising, depending on a capability of the UE to manage the conflict locally and / or failure to resolve the conflict locally, the UE performing one or more of the following: sending a request for conflict resolution assistance to the network, wherein details on the detected or unresolved conflict(s) are provided; receiving a response from the network wherein the network: requests supplementary information related to the conflict(s); or provides instructions to resolve the conflict; sending a response message wherein:2024PF0067660 16.12.2025 the UE provides the supplementary information requested by the network; or upon performing the instructions received from the network to resolve the conflict(s) and based on whether the conflict was (or was not) resolved successfully, the UE acknowledges network assistance in conflict resolution or provides an error message indicating failure to resolve the conflict.

20. An apparatus comprising: one or more transceivers; a processor; a memory coupled to the processor including instructions for performing the method according to any of the previous claims 1 to 19.

21. A computer program for access device selection comprising computer instructions to execute the method steps in claims 1-19.

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