Method and system for providing home network routing information for remote user equipment (UE)-to-network (U2N) relay communications after failure of

Abstract

Methods and systems are disclosed for providing home network routing information (HNRI) for a remote UE after authentication failure, e.g., during establishment of user equipment (UE)-to-network (U2N) relay communications. In some aspects, a first UE can detect an authentication failure during establishment of a secure connection with a second UE, and in response to detecting the authentication failure, notify the second UE of the authentication failure. In addition, the HNRI of the first authentication node within the home network of the first UE is provided by the first UE, by the second UE, or by the second authentication node, from previous interactions involving the first UE, to a second authentication node within the home network of the second UE.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Provisional Patent Application No. 63 / 370,639, filed on August 5, 2022, entitled “METHODS AND SYSTEMS FOR PROVIDING HOME NETWORK ROUTING INFORMATION OF REMOTE USER EQUIPMENT (UE) FOLLOWING AUTHENTICATION FAILURE DURING ESTABLISHMENT OF UE-TO-NETWORK (U2N) RELAY COMMUNICATION,” which is assigned to the assignee of this application and is expressly incorporated herein by reference in its entirety. Background Art

[0003] Aspects of the present disclosure relate generally to wireless communications, and more particularly to communications between a network node within a home network of a remote user equipment (UE) and a network node within the home network of a UE-to-network (U2N) relay UE.

[0004] Wireless communication systems have evolved over many generations, including first generation analog wireless telephone service (1G), second generation (2G) digital wireless telephone service (including transitional 2.5G and 2.75G networks), third generation (3G) high speed data, wireless service with Internet capabilities, and fourth generation (4G) services (e.g., Long Term Evolution (LTE) or WiMax). There are many different types of wireless communication systems in use today, including cellular systems and personal communications service (PCS) systems. Examples of known cellular systems include the cellular analog Advanced Mobile Phone System (AMPS), and digital cellular systems based on code division multiple access (CDMA), frequency division multiple access (FDMA), time division multiple access (TDMA), Global System for Mobile Communications (GSM), and the like.

[0005] The fifth generation (5G) wireless standard, known as New Radio (NR), enables higher data transfer speeds, a greater number of connections, and better coverage, among other improvements. According to the Next Generation Mobile Networks Alliance, the 5G standard is designed to provide higher data rates, more accurate positioning (e.g., based on reference signals for positioning (RS-P), such as downlink, uplink, or sidelink positioning reference signals (PRS)), and other technical enhancements compared to previous standards. These enhancements, along with the use of higher frequency bands, advances in PRS processes and technologies, and high-density deployments of 5G enable high-precision positioning based on 5G. Summary of the invention

[0006] The following presents a simplified summary of the invention related to one or more aspects disclosed herein. Therefore, the following summary of the invention should neither be considered as an exhaustive overview related to all conceived aspects, nor should it be considered to identify key or decisive elements related to all conceived aspects or to delineate the scope associated with any particular aspect. Therefore, the sole purpose of the following summary of the invention is to present certain concepts related to one or more aspects of the mechanisms disclosed herein in a brief form before the detailed embodiments presented below.

[0007] In one aspect, a method for wireless communication at a first user equipment (UE) includes: in response to an authentication failure during establishment of a secure connection with a second UE, transmitting a notification of the authentication failure to the second UE; and providing the second UE with home network routing information (HNRI) for an authentication node within a home network of the first UE.

[0008] In one aspect, a method for wireless communication at a first UE includes: receiving a notification of an authentication failure during establishment of a secure connection between the second UE and the first UE from a second UE; receiving an HNRI of a first authentication node within a home network of the second UE from the second UE; and transmitting the HNRI of the first authentication node within the home network of the second UE to a second authentication node within the home network of the first UE.

[0009] In one aspect, a method for wireless communication at a network entity includes: receiving, from a first UE in a first home network of the network entity, a request for security material for a secure connection between the first UE and a second UE having a second home network different from the first home network, the request including a transaction identifier (TXI); determining an HNRI for the second home network based on the TXI; determining an authentication node within the second home network based on the HNRI for the second home network; and forwarding the request to the authentication node within the second home network.

[0010] In one aspect, an apparatus for wireless communication at a first UE includes: one or more memories; and one or more processors, the one or more processors coupled to the one or more memories, the one or more processors configured to cause the first UE to: in response to an authentication failure during establishment of a secure connection with a second UE, transmit a notification of the authentication failure to the second UE; and provide the second UE with an HNRI for an authentication node within a home network of the first UE.

[0011] In one aspect, an apparatus for wireless communication at a first UE includes: one or more memories; and one or more processors, the one or more processors coupled to the one or more memories, the one or more processors configured to cause the first UE to: receive a notification of an authentication failure during establishment of a secure connection between the second UE and the first UE from a second UE; receive an HNRI of a first authentication node within a home network of the second UE from the second UE; and transmit the HNRI of the first authentication node within the home network of the second UE to a second authentication node within the home network of the first UE.

[0012] In one aspect, an apparatus for wireless communication at a network entity includes: one or more memories; and one or more processors, the one or more processors coupled to the one or more memories, the one or more processors configured to cause the network entity to: receive, from a first UE in a first home network of the network entity, a request for security material for a secure connection between the first UE and a second UE having a second home network different from the first home network, the request including a TXI; determine an HNRI for the second home network based on the TXI; determine an authentication node within the second home network based on the HNRI for the second home network; and forward the request to the authentication node within the second home network.

[0013] In one aspect, a method of wireless communication performed at a first UE includes: detecting an authentication failure during establishment of a secure connection with a second UE; and in response to detecting the authentication failure, transmitting a notification of the authentication failure to the second UE; and providing the second UE with an HNRI for an authentication node within a home network of the first UE.

[0014] In one aspect, a method of wireless communication performed at a first UE includes: receiving a notification of an authentication failure during establishment of a secure connection between the second UE and the first UE from a second UE; determining an HNRI of an authentication node within a home network for the second UE; and transmitting the HNRI of the authentication node within the home network for the second UE to an authentication node within the home network of the first UE.

[0015] On the one hand, a method of wireless communication includes: at a network entity: receiving a request for security material for a secure connection between a first UE in a home network of the network entity and a second UE that is not in the home network of the first UE, the request including a TXI; determining an HNRI for the home network of the second UE based on the TXI; determining an authentication node within the home network of the second UE based on the HNRI; and forwarding the request to the authentication node within the home network of the second UE.

[0016] In one aspect, a first UE includes: a memory; and at least one processor, the at least one processor coupled to the memory, the memory and the at least one processor configured to: detect an authentication failure during establishment of a secure connection with a second UE; and in response to detecting the authentication failure, transmit a notification of the authentication failure to the second UE; and provide the second UE with an HNRI of an authentication node within a home network of the first UE.

[0017] In one aspect, a first UE includes: a memory; and at least one processor, the at least one processor coupled to the memory, the memory and the at least one processor configured to: receive a notification of an authentication failure during establishment of a secure connection between the second UE and the first UE from a second UE; determine an HNRI of an authentication node within a home network for the second UE; and transmit the HNRI of the authentication node within the home network for the second UE to the authentication node within the home network of the first UE.

[0018] In one aspect, a network entity includes: a memory; and at least one processor, the at least one processor coupled to the memory, the memory and the at least one processor configured to: receive a request for security material for a secure connection between a first UE in a home network of the network entity and a second UE that is not in the home network of the first UE, the request including a TXI; determine an HNRI for the home network of the second UE based on the TXI; determine an authentication node within the home network of the second UE based on the HNRI; and forward the request to the authentication node within the home network of the second UE.

[0019] In one aspect, a first UE includes: a component for detecting an authentication failure during establishment of a secure connection with a second UE; and a component for transmitting a notification of the authentication failure to the second UE and providing the second UE with an HNRI of an authentication node within a home network of the first UE in response to detecting the authentication failure.

[0020] In one aspect, a first UE includes: a component for receiving a notification of an authentication failure during establishment of a secure connection between the second UE and the first UE from a second UE; a component for determining an HNRI of an authentication node within a home network for the second UE; and a component for transmitting the HNRI of the authentication node within the home network for the second UE to the authentication node within the home network of the first UE.

[0021] In one aspect, a network entity includes: a component for receiving, from a first UE in a home network of the network entity, a request for security material for a secure connection between the first UE and a second UE that is not in the home network of the first UE, the request including a TXI; a component for determining an HNRI for the home network of the second UE based on the TXI; a component for determining an authentication node within the home network of the second UE based on the HNRI; and a component for forwarding the request to the authentication node within the home network of the second UE.

[0022] In one aspect, a non-transitory computer-readable medium storing at least one computer-executable instruction, which when executed by a first UE causes the first UE to: detect an authentication failure during establishment of a secure connection with a second UE; and in response to detecting the authentication failure, transmit a notification of the authentication failure to the second UE; and provide the second UE with an HNRI for an authentication node within a home network of the first UE.

[0023] In one aspect, a non-transitory computer-readable medium stores at least one computer-executable instruction, which, when executed by a first UE, causes the first UE to: receive a notification of an authentication failure during establishment of a secure connection between the second UE and the first UE from a second UE; determine an HNRI for an authentication node within a home network of the second UE; and transmit the HNRI for the authentication node within the home network of the second UE to an authentication node within the home network of the first UE.

[0024] In one aspect, a non-transitory computer-readable medium storing at least one computer-executable instruction, which when executed by a network entity causes the network entity to: receive a request for security material for a secure connection between a first UE in a home network of the network entity and a second UE that is not in the home network of the first UE, the request including a TXI; determine an HNRI for the home network of the second UE based on the TXI; determine an authentication node within the home network of the second UE based on the HNRI; and forward the request to the authentication node within the home network of the second UE.

[0025] Other objects and advantages associated with the various aspects disclosed herein will be apparent to those skilled in the art based on the drawings and detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings are presented to aid in describing various aspects of the present disclosure and are provided solely for illustration and not limitation of the aspects.

[0027] Figure 1 An example wireless communication system in accordance with aspects of the present disclosure is illustrated.

[0028] Figure 2A , Figure 2B and Figure 2C Example wireless network structures according to aspects of the present disclosure are illustrated.

[0029] Figure 3A , Figure 3B and Figure 3C is a simplified block diagram of several sample aspects of components that may be employed in a user equipment (UE), a base station, and a network entity, respectively, and configured to support communications as taught herein.

[0030] Figure 4 is a signaling and event diagram illustrating user plane (UP) based security procedures involving layer 3 (L3) UE to network (U2N) relay.

[0031] Figure 5A and Figure 5B is a signaling and event diagram illustrating parts of the control plane (CP) based security procedures involving L3 U2N relay.

[0032] Figure 6 A resynchronization process using a user plane based security procedure is illustrated.

[0033] Figure 7 A resynchronization process using a control plane based security procedure is illustrated.

[0034] Fig. 8A , Figure 8B and Figure 8C is a signaling and event diagram illustrating different methods for providing home network routing information of a remote UE using UP-based security procedures in accordance with aspects of the present disclosure.

[0035] Fig. 9A , Fig. 9B and Fig. 9C is a signaling and event diagram illustrating different methods for providing home network routing information of a remote UE using CP-based security procedures in accordance with aspects of the present disclosure.

[0036] Fig.10is a flow chart of example processes performed by a remote UE associated with methods and systems for providing an HNRI of a remote UE after an authentication failure during establishment of U2N relay communications with a relay UE in accordance with aspects of the present disclosure.

[0037] Fig.11 is a flow chart of example processes performed by a U2N relay UE associated with methods and systems for providing an HNRI of a remote UE after an authentication failure during establishment of U2N relay communications with the remote UE in accordance with aspects of the present disclosure.

[0038] Fig.12 is a flow chart of example processes performed by a network node associated with methods and systems for providing an HNRI of a remote UE after an authentication failure during establishment of U2N relay communications between the remote UE and a relay UE in accordance with aspects of the present disclosure.

[0039] Fig.13 , Fig.14 and Fig.15 is a simplified block diagram of several example aspects of an electronic device configured to support providing a remote UE's HNRI after an authentication failure during establishment of U2N relay communications between the remote UE and a relay UE in accordance with aspects of the present disclosure.

[0040] Fig.16 is a flow chart of another example process performed by a remote UE associated with methods and systems for providing an HNRI of a remote UE after an authentication failure during establishment of U2N relay communications with a relay UE in accordance with aspects of the present disclosure.

[0041] Fig.17 is a flow chart of another example process performed by a U2N relay UE associated with methods and systems for providing an HNRI of a remote UE after an authentication failure during establishment of U2N relay communications with the remote UE in accordance with aspects of the present disclosure.

[0042] Fig.18 is a flow chart of another example process performed by a network node associated with methods and systems for providing an HNRI of a remote UE after an authentication failure during establishment of U2N relay communications between the remote UE and a relay UE in accordance with aspects of the present disclosure.

[0043] Fig.19 and Fig. 20 is a simplified block diagram of several example aspects of an electronic device configured to support providing a remote UE's HNRI after an authentication failure during establishment of U2N relay communications between the remote UE and a relay UE in accordance with aspects of the present disclosure. DETAILED DESCRIPTION

[0044] Sidelink communication is communication that occurs directly between a user equipment (UE) and another UE, rather than through a base station. In some types of sidelink communication, the communication link is established by or with the help of a base station, after which the two UEs communicate directly with each other. In other types of sidelink communication, the communication link may be established without the need for a base station or without assistance from a base station. In one form of sidelink communication, communication may be established using so-called proximity services, or "ProSe" for short. Proximity services allow UEs to find and connect to each other, including establishing secure connections between UEs.

[0045] When a first UE also provides connectivity into a network for a second UE connected to the first UE via a sidelink communication link (regardless of whether the sidelink communication is a ProSe connection), the first UE is referred to as a UE-to-network (U2N) relay (and may be referred to as a "U2N relay UE" or just a "relay UE"), and the second UE is referred to as a "remote UE" (and may be referred to as a "U2N remote UE"). In this scenario, the remote UE and the relay UE are authenticated and the connection between the remote UE and the relay UE is securely protected using security material provided by authorization and authentication nodes within the remote UE's home network and within the relay UE's home network. Some of these security materials may be associated with a time limit or "freshness" parameter such that they are only valid for a limited amount of time, after which they expire and become invalid.

[0046] As used herein, the term "security material" refers to any element or information related to security protection, including information necessary to protect the transmission or reception of messages. Examples of security material include, but are not limited to, security keys, key IDs, expiration times, the identity of the algorithms used (e.g., the selected PC5 encryption algorithm), and parameters used by such algorithms (such as code reception security parameters or code transmission security parameters, etc.). As used herein, the term "confidentiality protection" applied to a message means protecting the message to prevent unauthorized access to information contained within the message. As used herein, the term "integrity protection" applied to a message means protecting the message to ensure that the message has not been modified since it was created and sent, which extends to detecting when a message has been modified.

[0047] When the remote UE is unable to authenticate the relay, this is referred to herein as a U2N relay UE authentication failure, or simply "authentication failure". When the dd fails due to invalid (e.g., incorrect or expired) security material, such as when the authentication vector provided by the relay UE to the remote UE is not within a set of one or more expected values ​​(this is referred to as a specific type of authentication failure (so-called "synchronization failure")), the remote UE must give notification of the authentication failure to the entity seeking to be authenticated (in this case the U2N relay UE).

[0048] When a synchronization failure occurs, a process referred to as "resynchronization" may be performed to retrieve an updated authentication challenge for retrying authentication. Resynchronization involves interaction between a first authentication node, which is an authentication node in the home network of the relay UE (and thus the authentication node may be referred to herein as the "authentication node of the relay UE"), and a second authentication node, which is an authentication node in the home network of the remote UE (and thus the authentication node may be referred to herein as the "authentication node of the remote UE").

[0049] When the interaction is initiated by the first authentication node, the first authentication node needs to know how to contact the second authentication node, that is, the first authentication node needs to know the home network routing information (HNRI) for the second authentication node (eg, the network address of the home network or other network identifier).

[0050] How the first authentication node possesses this network address or network identifier of the home network of the second authentication node is not specified by existing telecommunication standards, and the message received by the first authentication node to trigger the resynchronization process does not contain any HNRI for the second authentication node, so the source of this information and the mechanism by which this information reaches the first authentication node are undefined.

[0051] To resolve this ambiguity, disclosed herein is a method and system for providing an HNRI (hereinafter may be referred to as “HNRI”) of an authentication node of a remote UE to an authentication node of a relay UE after authentication failure during establishment of U2N relay communication between the remote UE and the relay UE.

[0052] According to aspects of the present disclosure, the HNRI of the authentication node of the remote UE is provided to the authentication node of the relay UE by the remote UE, by the relay UE, or because it is stored by the authentication node of the relay UE from a previous interaction involving the remote UE. Using this information, the authentication node of the relay UE can interact with the authentication node of the remote UE, for example, to provide an updated authentication challenge, which will be used for authentication of a secure connection between the remote UE and the relay UE and / or a secure connection between the remote UE and a network that the relay UE gives the remote UE access, such as the above-mentioned resynchronization procedure. Therefore, the technology disclosed herein provides an established procedure by which the authentication node of the relay UE obtains the HNRI of the authentication node of the remote UE.

[0053] Regarding how the relay UE obtains the HNRI of the remote UE's authentication node provided by the relay UE to the relay UE's authentication node, this document describes several methods:

[0054] • In some aspects, the remote UE provides the HNRI as part of a message that the remote UE transmits to the relay UE to notify the relay UE that the remote UE failed to authenticate the relay UE (which message may be referred to herein as an "authentication failure message").

[0055] • In some aspects, the remote UE provides the HNRI in an additional message that the remote UE transmits to the relay UE separately from the authentication failure message.

[0056] • In some aspects, the remote UE will have previously provided the HNRI to the relay UE as part of the direct communication request, and the relay UE will have stored the HNRI; when the relay UE later receives the authentication failure message, the relay UE may retrieve the previously stored HNRI.

[0057] In some aspects, the remote UE will have previously provided the HNRI to the relay UE as part of the direct communication request, and at this time the relay UE will generate and store a transaction identifier (TXI) in response to receiving the direct communication request from the remote UE, and provide both the HNRI and the TXI to the relay UE's authentication node. The relay UE's authentication node stores a mapping of the TXI to the HNRI. When the relay UE later receives an authentication failure message, the relay UE provides the TXI to the relay UE's authentication node, which uses the TXI to look up the correct HNRI.

[0058] Using so-called proximity services, or "ProSe" for short, sidelink communications between a user equipment (UE) and another UE may be established without the need for, or assistance from, a base station. Proximity services allow UEs to find and connect to each other, including establishing a secure connection between the UEs. When a first UE also provides a connection into a network for a second UE, the first UE is called a UE-to-network (U2N) relay (and may be referred to as a "U2N relay UE" or just a "relay UE"), and the second UE is called a "remote UE". In this scenario, the remote UE and the relay UE must be authenticated and the connection between the remote UE and the relay UE must be securely protected, using security material provided by authorization and authentication nodes within the remote UE's home network and within the relay UE's home network.

[0059] When the authentication step fails, for example because the security material is invalid or expired, the remote UE must give a notification of the authentication failure. An example of such a process when synchronization failure occurs is called "resynchronization". Resynchronization is performed to retrieve an updated verification challenge for retrying the verification. Resynchronization involves interaction between a first authentication node in the home network of the relay UE and a second authentication node in the home network of the remote UE. When the interaction is initiated by the first authentication node, the first authentication node needs to know how to contact the second authentication node, that is, the first authentication node needs to know the home network routing information (HNRI) for the second authentication node (for example, the address of the home network or other network identifier). How the first authentication node specifically possesses the network address or network identifier of the home network of the second authentication node is not specified by existing telecommunications standards, and the message received by the first authentication node to trigger the resynchronization process does not contain any HNRI for the second authentication node.

[0060] To resolve this ambiguity, methods and systems for providing an HNRI of a remote UE after an authentication failure during establishment of U2N relay communications between a remote UE and a relay UE are disclosed herein. In some aspects, a first UE (e.g., a remote UE) may detect an authentication failure during establishment of a secure connection with a second UE (e.g., a relay UE), and in response to detecting the authentication failure, notify the second UE of the authentication failure. The second UE then signals a second authentication node within the home network of the second UE. The HNRI of the first authentication node within the home network of the first UE is provided to the second authentication node by the first UE, by the second UE, or because it is stored by the second authentication node from a previous interaction involving the first UE, so that the second authentication node can interact with the first authentication node, for example, to provide an updated authentication challenge, which will be used for authentication of a secure connection between the remote UE and the relay UE and / or a secure connection between the remote UE and a network to which the relay UE gives the remote UE access.

[0061] Various aspects of the present disclosure are provided in the following description and related drawings for various examples provided for illustrative purposes. Alternative aspects may be designed without departing from the scope of the present disclosure. In addition, well-known elements of the present disclosure will not be described in detail or will be omitted to avoid making the relevant details of the present disclosure difficult to understand.

[0062] The words "exemplary" and / or "example" are used herein to mean "serving as an example, instance, or illustration." Any aspect described herein as "exemplary" and / or "example" is not necessarily to be construed as preferred or advantageous over other aspects. Likewise, the term "aspects of the disclosure" does not require that all aspects of the disclosure include the discussed feature, advantage, or mode of operation.

[0063] Those skilled in the art will appreciate that any of a variety of different techniques and methods may be used to represent the information and signals described below. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be mentioned throughout the following description may be represented by voltage, current, electromagnetic waves, magnetic fields or magnetic particles, light fields or optical particles, or any combination thereof, which depends in part on the specific application, in part on the desired design, in part on the corresponding technology, and so on.

[0064] In addition, many aspects are described in terms of a sequence of actions to be performed by, for example, an element of a computing device. It will be appreciated that the various actions described herein may be performed by a specific circuit (e.g., an application specific integrated circuit (ASIC)), by program instructions executed by one or more processors, or by a combination of the two. In addition, the sequence of actions described herein may be considered to be fully embodied in any form of non-transient computer-readable storage medium, in which a corresponding computer instruction set is stored, which, when executed, will cause or command the associated processor of the device to perform the functions described herein. Therefore, various aspects of the present disclosure may be embodied in a variety of different forms, all of which have been contemplated to be within the scope of the claimed subject matter. In addition, for each of the various aspects described herein, the corresponding form of any such aspect may be described herein as, for example, "logic configured to perform the described actions".

[0065] As used herein, unless otherwise specified, the terms "user equipment" (UE) and "base station" are not intended to be specific or otherwise limited to any particular radio access technology (RAT). In general, a UE can be any wireless communication device used by a user to communicate over a wireless communication network (e.g., a mobile phone, a router, a tablet computer, a laptop computer, a consumer asset location device, a wearable device (e.g., a smart watch, glasses, an augmented reality (AR) / virtual reality (VR) headset, etc.), a vehicle (e.g., a car, a motorcycle, a bicycle, etc.), an Internet of Things (IoT) device, etc.). A UE can be mobile or can be stationary (e.g., at certain times) and can communicate with a radio access network (RAN). As used herein, the term "UE"' may be interchangeably referred to as an "access terminal" or "AT", "client device", "wireless device", "subscriber equipment", "subscriber terminal", "subscriber station", "user terminal" or "UT", "mobile device", "mobile terminal", "mobile station" or variations thereof. In general, the UE can communicate with the core network via the RAN, and through the core network, the UE can be connected to an external network such as the Internet and other UEs. Of course, other mechanisms for connecting to the core network and / or the Internet are also possible for the UE, such as through a wired access network, a wireless local area network (WLAN) network (e.g., based on the Institute of Electrical and Electronics Engineers (IEEE) 802.11 specification, etc.), etc.

[0066] A base station may operate according to one of several RATs to communicate with a UE, depending on the network in which the base station is deployed, and may alternatively be referred to as an access point (AP), a network node, a Node B, an evolved Node B (eNB), a next generation eNB (ng-eNB), a new radio (NR) Node B (also referred to as a gNB or gNodeB), etc. A base station may be primarily used to support wireless access for UEs, including supporting data, voice, and / or signaling connections for supported UEs. In some systems, a base station may provide only edge node signaling functions, while in other systems, it may provide additional control and / or network management functions. The communication link by which a UE may transmit a signal to a base station is referred to as an uplink (UL) channel (e.g., a reverse traffic channel, a reverse control channel, an access channel, etc.). The communication link by which a base station may transmit a signal to a UE is referred to as a downlink (DL) or forward link channel (e.g., a paging channel, a control channel, a broadcast channel, a forward traffic channel, etc.). As used herein, the term "traffic channel (TCH)" may refer to an uplink / reverse traffic channel or a downlink / forward traffic channel.

[0067] The term "base station" may refer to a single physical transmit receive point (TRP) or to multiple physical TRPs that may or may not be co-located. For example, where the term "base station" refers to a single physical TRP, the physical TRP may be an antenna of the base station corresponding to a cell (or several cell sectors) of the base station. Where the term "base station" refers to multiple co-located physical TRPs, the physical TRP may be an antenna array of the base station (e.g., as in a multiple-input multiple-output (MIMO) system or where the base station employs beamforming). Where the term "base station" refers to multiple non-co-located physical TRPs, the physical TRP may be a distributed antenna system (DAS) (a network of spatially separated antennas connected to a common source via a transmission medium) or a remote radio head (RRH) (a remote base station connected to a serving base station). Alternatively, the non-co-located physical TRP may be a serving base station that receives measurement reports from a UE and a neighboring base station whose reference radio frequency (RF) signal the UE is measuring. Because, as used herein, a TRP is a point by which a base station transmits and receives wireless signals, references to transmitting from a base station or receiving at a base station should be understood to refer to a specific TRP of a base station.

[0068] In some specific implementations of supporting UE positioning, the base station may not support wireless access for the UE (e.g., may not support data, voice, and / or signaling connections for the UE), but may instead send a reference signal to be measured by the UE to the UE and / or may receive and measure a signal sent by the UE. Such a base station may be referred to as a positioning beacon (e.g., in the case of sending a signal to the UE) and / or as a position measurement unit (e.g., in the case of receiving and measuring a signal from the UE).

[0069] An "RF signal" includes an electromagnetic wave of a given frequency that transmits information through the space between a transmitter and a receiver. As used herein, a transmitter may send a single "RF signal" or multiple "RF signals" to a receiver. However, due to the propagation characteristics of RF signals through multipath channels, a receiver may receive multiple "RF signals" corresponding to each transmitted RF signal. The same transmitted RF signal on different paths between a transmitter and a receiver may be referred to as a "multipath" RF signal. As used herein, an RF signal may also be referred to as a "wireless signal" or simply a "signal" where it is clear from the context that the term "signal" refers to either a wireless signal or an RF signal.

[0070] Figure 1An example wireless communication system 100 is illustrated in accordance with various aspects of the present disclosure. The wireless communication system 100 (which may also be referred to as a wireless wide area network (WWAN)) may include various base stations 102 (labeled as "BS") and various UEs 104. The base stations 102 may include macrocell base stations (high-power cellular base stations) and / or small cell base stations (low-power cellular base stations). In an aspect, the macrocell base stations may include eNBs and / or ng-eNBs (where the wireless communication system 100 corresponds to an LTE network) or gNBs (where the wireless communication system 100 corresponds to an NR network) or a combination of the two, and the small cell base stations may include femtocells, picocells, microcells, etc. Some UEs 104 may operate as relay UEs for other UEs 104. In some aspects, the UEs 104 may include a ProSe module 106 for managing some aspects of ProSe communications between UEs.

[0071] The base stations 102 may collectively form a RAN and interface with a core network 170 (e.g., an evolved packet core (EPC) or a 5G core (5GC)) through a backhaul link 122, and interface with one or more location servers 172 (e.g., a location management function (LMF) or a secure user plane location (SUPL) location platform (SLP)) through the core network 170. The location server 172 may be part of the core network 170 or may be external to the core network 170. The location server 172 may be integrated with the base station 102. The UE 104 may communicate with the location server 172 directly or indirectly. For example, the UE 104 may communicate with the location server 172 via the base station 102 currently serving the UE 104. The UE 104 may also communicate with the location server 172 via another path, such as via an application server (not shown), via another network, such as via a wireless local area network (WLAN) access point (AP) (e.g., AP 150 described below), etc. For signaling purposes, communication between the UE 104 and the location server 172 may be represented as an indirect connection (e.g., through the core network 170, etc.) or a direct connection (e.g., as shown via the direct connection 128), wherein intermediate nodes (if any) are omitted from the signaling diagram for clarity. The core network 170 may include an authentication node 174, such as an access and mobility management function (AMF), an authentication server function (AUSF), or a ProSe key management function (PKMF), which may also include the ProSe module 106.

[0072] Among other functions, the base station 102 may perform functions related to one or more of the following: delivering user data, radio channel encryption and decryption, integrity protection, header compression, mobility control functions (e.g., handover, dual connectivity), inter-cell interference coordination, connection establishment and release, load balancing, distribution of non-access stratum (NAS) messages, NAS node selection, synchronization, RAN sharing, multimedia broadcast multicast service (MBMS), subscriber and equipment tracking, RAN information management (RIM), paging, positioning, and delivery of warning messages. The base stations 102 may communicate with each other directly or indirectly (e.g., through EPC / 5GC) over a backhaul link 134, which may be wired or wireless.

[0073] Base station 102 may communicate wirelessly with UE 104. Each of base stations 102 may provide communication coverage for a corresponding geographic coverage area 110. In one aspect, one or more cells may be supported by base station 102 in each geographic coverage area 110. A "cell" is a logical communication entity used to communicate with a base station (e.g., on a frequency resource, which is referred to as a carrier frequency, component carrier, carrier, frequency band, etc.), and may be associated with an identifier (e.g., a physical cell identifier (PCI), an enhanced cell identifier (ECI), a virtual cell identifier (VCI), a cell global identifier (CGI), etc.) used to distinguish cells operating via the same or different carrier frequencies. In some cases, different cells may be configured according to different protocol types (e.g., machine type communication (MTC), narrowband IoT (NB-IoT), enhanced mobile broadband (eMBB), or other protocol types) that may provide access to different types of UEs. Because a cell is supported by a specific base station, the term "cell" may refer to either or both of the logical communication entity and the base station supporting it, depending on the context. In addition, because the TRP is generally the physical transmission point of the cell, the terms "cell" and "TRP" may be used interchangeably. In some cases, the term "cell" may also refer to the geographic coverage area (e.g., sector) of a base station, as long as the carrier frequency can be detected and used for communications within a portion of the geographic coverage area 110.

[0074] Although the geographic coverage areas 110 of neighboring macrocell base stations 102 may partially overlap (e.g., in a handover region), some of the geographic coverage areas 110 may substantially overlap with the larger geographic coverage areas 110. For example, a small cell base station 102′ (labeled “SC” for “small cell”) may have a geographic coverage area 110′ that substantially overlaps with the geographic coverage areas 110 of one or more macrocell base stations 102. A network that includes both small cell base stations and macrocell base stations may be referred to as a heterogeneous network. A heterogeneous network may also include a home eNB (HeNB), which may provide services to a restricted group called a closed subscriber group (CSG).

[0075] The communication link 120 between the base station 102 and the UE 104 may include uplink (also referred to as reverse link) transmissions from the UE 104 to the base station 102 and / or downlink (DL) (also referred to as forward link) transmissions from the base station 102 to the UE 104. The communication link 120 may use MIMO antenna technology, including spatial multiplexing, beamforming, and / or transmit diversity. The communication link 120 may be over one or more carrier frequencies. The allocation of carriers may be asymmetric for the downlink and uplink (e.g., more or fewer carriers may be allocated to the downlink than to the uplink).

[0076] The wireless communication system 100 may also include a WLAN access point (AP) 150 that communicates with a wireless local area network (WLAN) station (STA) 152 in an unlicensed spectrum (e.g., 5 GHz) via a communication link 154. When communicating in the unlicensed spectrum, the WLAN STA 152 and / or the WLAN AP 150 may perform a clear channel assessment (CCA) or listen before talk (LBT) procedure prior to communication to determine whether a channel is available.

[0077] The small cell base station 102' can operate in licensed and / or unlicensed spectrum. When operating in the unlicensed spectrum, the small cell base station 102' can adopt LTE or NR technology and use the same 5GHz unlicensed spectrum used by the WLAN AP 150. The small cell base station 102' using LTE / 5G in the unlicensed spectrum can improve the coverage of the access network and / or increase the capacity of the access network. NR in the unlicensed spectrum can be referred to as NR-U. LTE in the unlicensed spectrum can be referred to as LTE-U, Licensed Assisted Access (LAA) or MulteFire.

[0078] The wireless communication system 100 may also include a millimeter wave (mmW) base station 180, which can operate at mmW frequencies and / or near mmW frequencies to communicate with UE 182. Extremely high frequency (EHF) is part of RF in the electromagnetic spectrum. EHF has a range of 30 GHz to 300 GHz, with a wavelength between 1 mm and 10 mm. The radio waves in this band may be referred to as millimeter waves. Near mmW can be extended downward to a frequency of 3 GHz, with a wavelength of 100 mm. The super high frequency (SHF) band extends between 3 GHz and 30 GHz, and it is also referred to as centimeter waves. Communications using mmW / near mmW radio frequency bands have high path loss and relatively short distances. The mmW base station 180 and the UE 182 may utilize beamforming (transmitting and / or receiving) on ​​the mmW communication link 184 to compensate for extremely high path loss and short distances. In addition, it should be understood that in an alternative configuration, one or more base stations 102 may also use mmW or near mmW and beamforming for transmission. Therefore, it should be understood that the foregoing illustrations are merely examples and should not be construed as limiting the various aspects disclosed herein.

[0079] Transmit beamforming is a technique for focusing an RF signal in a specific direction. Traditionally, when a network node (e.g., a base station) broadcasts an RF signal, it broadcasts the signal in all directions (omnidirectionally). With transmit beamforming, the network node determines where a given target device (e.g., a UE) is located (relative to the transmitting network node) and projects a stronger downlink RF signal in that specific direction, thereby providing a faster (in terms of data rate) and stronger RF signal to the receiving device. In order to change the directionality of the RF signal when transmitting, the network node can control the phase and relative amplitude of the RF signal at each of the one or more transmitters that broadcast the RF signal. For example, a network node can use an array of antennas (called a "phased array" or "antenna array") that creates RF beams that can be "manipulated" to point in different directions without actually moving the antennas. Specifically, the RF current from the transmitter is fed to each antenna in the correct phase relationship so that the radio waves from the separate antennas are added together to increase the radiation in the desired direction while canceling to suppress the radiation in the undesired direction.

[0080] The transmit beams can be quasi-co-located, which means that they appear to the receiver (e.g., UE) to have the same parameters, regardless of whether the network node's own transmit antenna is physically co-located. In NR, there are four types of quasi-co-location (QCL) relationships. Specifically, a given type of QCL relationship means that certain parameters about the second reference RF signal on the second beam can be derived based on information about the source reference RF signal on the source beam. Therefore, if the source reference RF signal is QCL type A, the receiver can use the source reference RF signal to estimate the Doppler shift, Doppler spread, average delay, and delay spread of the second reference RF signal sent on the same channel. If the source reference RF signal is QCL type B, the receiver can use the source reference RF signal to estimate the Doppler shift and Doppler spread of the second reference RF signal sent on the same channel. If the source reference RF signal is QCL type C, the receiver can use the source reference RF signal to estimate the Doppler shift and average delay of the second reference RF signal sent on the same channel. If the source reference RF signal is QCL type D, the receiver may use the source reference RF signal to estimate spatial reception parameters of a second reference RF signal transmitted on the same channel.

[0081] In receive beamforming, the receiver uses receive beams to amplify RF signals detected on a given channel. For example, the receiver may increase the gain setting of the antenna array in a particular direction and / or adjust the phase setting of the antenna array in a particular direction to amplify the RF signal received from that direction (e.g., increase its gain level). Therefore, when a receiver is said to perform beamforming in a certain direction, it means that the beam gain in that direction is high relative to the beam gain along other directions, or the beam gain in that direction is the highest compared to the beam gain in that direction of all other receive beams available to the receiver. This results in a stronger received signal strength (e.g., reference signal received power (RSRP), reference signal received quality (RSRQ), signal to interference plus noise ratio (SINR), etc.) of the RF signal received from that direction.

[0082] The transmit beam and the receive beam may be spatially correlated. The spatial relationship means that parameters of a second beam (e.g., a transmit beam or a receive beam) for a second reference signal may be derived based on information about a first beam (e.g., a receive beam or a transmit beam) for a first reference signal. For example, a UE may use a specific receive beam to receive a reference downlink reference signal (e.g., a synchronization signal block (SSB)) from a base station. The UE may then form a transmit beam for transmitting an uplink reference signal (e.g., a sounding reference signal (SRS)) to the base station based on the parameters of the receive beam.

[0083] Note that depending on the entity forming the "downlink" beam, the beam can be a transmit beam or a receive beam. For example, if the base station is forming a downlink beam to send a reference signal to the UE, the downlink beam is a transmit beam. However, if the UE is forming a downlink beam, the downlink beam is a receive beam that receives a downlink reference signal. Similarly, depending on the entity forming the "uplink" beam, the beam can be a transmit beam or a receive beam. For example, if the base station is forming an uplink beam, it is an uplink receive beam, and if the UE is forming an uplink beam, it is an uplink transmit beam.

[0084] The electromagnetic spectrum is typically subdivided into various categories, bands, channels, etc. based on frequency / wavelength. In 5GNR, two initial operating bands have been identified as frequency range designations FR1 (410 MHz-7.125 GHz) and FR2 (24.25 GHz-52.6 GHz). It should be understood that although a portion of FR1 is greater than 6 GHz, FR1 is often (interchangeably) referred to as the "below 6 GHz" band in various documents and articles. A similar naming problem sometimes occurs with respect to FR2, which is often (interchangeably) referred to as the "millimeter wave" band in documents and articles, although different from the extremely high frequency (EHF) band (30 GHz-300 GHz) identified as the "millimeter wave" band by the International Telecommunication Union (ITU).

[0085] Frequencies between FR1 and FR2 are generally referred to as mid-band frequencies. Recent 5G NR research has identified the operating bands for these mid-band frequencies as frequency range designation FR3 (7.125GHz-24.25GHz). The bands falling within FR3 can inherit FR1 characteristics and / or FR2 characteristics, so the features of FR1 and / or FR2 can be effectively extended to mid-band frequencies. In addition, higher frequency bands are currently being explored to extend 5G NR operations to more than 52.6GHz. For example, three higher operating bands have been identified as frequency range designations FR4a or FR4-1 (52.6GHz-71GHz), FR4 (52.6GHz-114.25GHz) and FR5 (114.25GHz-300GHz). Each of these higher frequency bands falls within the EHF band.

[0086] In view of the above aspects, unless otherwise specifically stated, it should be understood that if used in this article, the term "below 6 GHz" and the like can be broadly referred to as frequencies that can be less than 6 GHz, can be within FR1, or can include mid-band frequencies. In addition, unless otherwise specifically stated, it should be understood that if the term "millimeter wave" and the like are used in this article, they can be broadly referred to as frequencies that can include mid-band frequencies, can be within FR2, FR4, FR4-a or FR4-1 and / or FR5, or can be within the EHF band.

[0087] In a multi-carrier system (such as 5G), one of the carrier frequencies is referred to as the "primary carrier" or "anchor carrier" or "primary serving cell" or "PCell", and the remaining carrier frequencies are referred to as "secondary carriers" or "secondary serving cells" or "SCells". In carrier aggregation, the anchor carrier is a carrier operating on the primary frequency (e.g., FR1) used by the UE 104 / 182 and the cell in which the UE 104 / 182 performs an initial radio resource control (RRC) connection establishment procedure or initiates an RRC connection re-establishment procedure. The primary carrier carries all common and UE-specific control channels and can be a carrier in a licensed frequency (however, this is not always the case). A secondary carrier is a carrier operating on a second frequency (e.g., FR2), which can be configured and used to provide additional radio resources once an RRC connection is established between the UE 104 and the anchor carrier. In some cases, the secondary carrier can be a carrier in an unlicensed frequency. The secondary carrier may contain only necessary signaling information and signals, for example, since the primary uplink carrier and the primary downlink carrier are usually UE-specific, those UE-specific signaling information and signals may not be present in the secondary carrier. This means that different UEs 104 / 182 in a cell may have different downlink primary carriers. The same is true for the uplink primary carrier. The network is able to change the primary carrier of any UE 104 / 182 at any time. This is done, for example, to balance the load on different carriers. Because a "serving cell" (whether PCell or SCell) corresponds to a carrier frequency / component carrier on which a base station communicates, the terms "cell", "serving cell", "component carrier", "carrier frequency", etc. are used interchangeably.

[0088] For example, still refer to Figure 1, one of the frequencies used by macrocell base station 102 may be an anchor carrier (or "PCell"), and the other frequencies used by macrocell base station 102 and / or mmW base station 180 may be secondary carriers ("SCells"). Simultaneous transmission and / or reception of multiple carriers enables UE 104 / 182 to significantly increase its data transmission and / or reception rate. For example, two 20 MHz aggregated carriers in a multi-carrier system would theoretically result in a doubling of the data rate (i.e., 40 MHz) compared to the data rate obtained with a single 20 MHz carrier.

[0089] The wireless communication system 100 may also include a UE 164, which may communicate with the macrocell base station 102 via a communication link 120 and / or communicate with the mmW base station 180 via a mmW communication link 184. For example, the macrocell base station 102 may support a PCell and one or more SCells for the UE 164, and the mmW base station 180 may support one or more SCells for the UE 164.

[0090] In some cases, UE 164 and UE 182 are capable of sidelink communication. A UE with sidelink capability (SL-UE) can communicate with base station 102 via communication link 120 using a Uu interface (i.e., an air interface between UE and a base station). SL-UEs (e.g., UE 164, UE 182) can also communicate directly with each other via a wireless sidelink 160 using a PC5 interface (i.e., an air interface between UEs with sidelink capability). A wireless sidelink (or simply "sidelink") is an adaptation of a core cellular network (e.g., LTE, NR) standard that allows direct communication between two or more UEs without communicating through a base station. Sidelink communications can be unicast or multicast and can be used for device-to-device (D2D) media sharing, vehicle-to-vehicle (V2V) communications, vehicle-to-vehicle (V2X) communications (e.g., cellular V2X (cV2X) communications, enhanced V2X (eV2X) communications, etc.), emergency rescue applications, etc. One or more SL-UEs in a group of SL-UEs utilizing sidelink communications may be located within the geographic coverage area 110 of the base station 102. Other SL-UEs in such a group may be outside the geographic coverage area 110 of the base station 102, or may be unable to receive transmissions from the base station 102 for other reasons. In some cases, each group of SL-UEs communicating via sidelink communications may utilize a one-to-many (1:M) system, where each SL-UE transmits to each other SL-UE in the group. In some cases, the base station 102 facilitates the scheduling of resources for sidelink communications. In other cases, sidelink communications are performed between the SL-UEs without involving the base station 102.

[0091] In one aspect, the sidelink 160 may operate on a wireless communication medium of interest, which may be shared with other vehicles and / or infrastructure access points and other wireless communications between other RATs. A "medium" may include one or more time, frequency, and / or spatial communication resources associated with wireless communications between one or more transmitter / receiver pairs (e.g., covering one or more channels across one or more carriers). In one aspect, the medium of interest may correspond to at least a portion of an unlicensed band shared between various RATs. Although different licensed bands have been reserved for certain communication systems (e.g., by government entities such as the Federal Communications Commission (FCC) in the United States), these systems (particularly those employing small cell access points) have recently expanded operations into unlicensed bands such as the Unlicensed National Information Infrastructure (U-NII) band used by wireless local area network (WLAN) technologies (most notably the IEEE 802.11x WLAN technology commonly referred to as "Wi-Fi"'). Example systems of this type include different variations of CDMA systems, TDMA systems, FDMA systems, Orthogonal FDMA (OFDMA) systems, Single-Carrier FDMA (SC-FDMA) systems, and the like.

[0092] Note that although Figure 1 Only two of these UEs are illustrated as SL-UEs (i.e., UEs 164 and 182), but any of the illustrated UEs may be SL-UEs. In addition, although only UE 182 is described as being capable of beamforming, any of the illustrated UEs (including UE 164) may be capable of beamforming. Where SL-UEs are capable of beamforming, they may beamform toward each other (i.e., toward other SL-UEs), toward other UEs (e.g., UE 104), toward base stations (e.g., base stations 102, 180, small cells 102′, access point 150), and the like. Thus, in some cases, UE 164 and UE 182 may utilize beamforming via side link 160.

[0093] exist Figure 1 In the example of Figure 1104) can receive a signal 124 from one or more non-terrestrial vehicles (NTVs) 112, which can include earth orbiting space vehicles (e.g., satellites) and unmanned aerial vehicles (UAVs). In one aspect, NTV 112 can be part of a satellite positioning system that UE 104 can use as an independent source of location information. A satellite positioning system typically includes a transmitter system (e.g., NTV 112) that is positioned so that a receiver (e.g., UE 104) can determine its position on or above the earth based at least in part on a positioning signal (e.g., signal 124) received from the transmitter. Such a transmitter typically transmits a signal of a repeating pseudo-random noise (PN) code marked with a set number of chips. Although typically located in NTV 112, the transmitter may sometimes be located on a ground-based control station, base station 102, and / or other UE 104. UE 104 may include one or more dedicated receivers specifically designed to receive signal 124 in order to derive geographic location information from NTV 112 .

[0094] In a satellite positioning system, the use of signal 124 may be enhanced by various satellite-based augmentation systems (SBAS) that may be associated with or otherwise enabled for use with one or more global and / or regional navigation satellite systems. For example, SBAS may include augmentation systems that provide integrity information, differential corrections, etc., such as Wide Area Augmentation System (WAAS), European Geosynchronous Navigation Overlay Service (EGNOS), Multifunction Satellite Augmentation System (MSAS), Global Positioning System (GPS) Assisted Geographic Augmentation Navigation or GPS and Geographic Augmentation Navigation System (GAGAN), etc. Thus, as used herein, a satellite positioning system may include any combination of one or more global and / or regional navigation satellites associated with such one or more satellite positioning systems.

[0095] In one aspect, NTV 112 may additionally or alternatively be part of one or more non-terrestrial networks (NTNs). In the NTN, NTV 112 is connected to an earth station (also referred to as a ground station, NTN gateway, or gateway), which in turn is connected to an element in the 5G network, such as an improved base station 102 (without a ground antenna) or a network node in a 5GC. This element in turn will provide access to other elements in the 5G network, and ultimately provide access to entities outside the 5G network (such as Internet web servers and other user devices). In this way, instead of or in addition to communication signals from a ground base station 102, a UE 104 can receive communication signals (e.g., signal 124) from NTV 112.

[0096] The wireless communication system 100 may also include one or more UEs, such as UE 190, which are indirectly connected to one or more communication networks via one or more device-to-device (D2D) peer-to-peer (P2P) links (referred to as “side links”). Figure 1 In the example of FIG. 1 , UE 190 has a D2D P2P link 192 with one of UEs 104 connected to one of base stations 102 (e.g., UE 190 can indirectly obtain cellular connectivity through the D2D P2P link), and has a D2D P2P link 194 with WLAN STA 152 connected to WLAN AP 150 (UE 190 can indirectly obtain WLAN-based Internet connectivity through the D2D P2P link). In an example, D2D P2P links 192 and 194 can be supported by any well-known D2D RAT, such as LTE Direct (LTE-D), WiFi Direct (WiFi-D), etc.

[0097] Figure 2A An example wireless network structure 200 is illustrated. For example, the 5GC 210 (also referred to as the Next Generation Core (NGC)) can be functionally viewed as a control plane (C-plane) function 214 (e.g., UE registration, authentication, network access, gateway selection, etc.) and a user plane (U-plane) function 212 (e.g., UE gateway function, access to data networks, IP routing, etc.), which operate in conjunction to form a core network. The user plane interface (NG-U) 213 and the control plane interface (NG-C) 215 connect the gNB 222 to the 5GC 210, and specifically to the user plane function 212 and the control plane function 214, respectively. In an additional configuration, the ng-eNB 224 can also be connected to the 5GC 210 via the NG-C 215 to the control plane function 214 and the NG-U 213 to the user plane function 212. In addition, the ng-eNB 224 can communicate directly with the gNB 222 via the backhaul connection 223. In some configurations, the next generation RAN (NG-RAN) 220 may have one or more gNBs 222, while other configurations include one or more of ng-eNBs 224 and gNBs 222. Either the gNB 222 or the ng-eNB 224 (or both) may communicate with one or more UEs 204 (e.g., any of the UEs described herein).

[0098] Another optional aspect may include a location server 230 that can communicate with the 5GC 210 to provide location assistance for the UE 204. The location server 230 may be implemented as multiple separate servers (e.g., physically separate servers, different software modules on a single server, different software modules distributed across multiple physical servers, etc.), or alternatively may each correspond to a single server. The location server 230 may be configured to support one or more location services for the UE 204 that may be connected to the location server 230 via the core network, the 5GC 210, and / or via the Internet (not illustrated). In addition, the location server 230 may be integrated into a component of the core network, or alternatively may be external to the core network (e.g., a third-party server, such as an original equipment manufacturer (OEM) server or a service server).

[0099] Figure 2B Another example wireless network structure 240 is illustrated. 5GC 260 (which may correspond to Figure 2AThe 5GC 210 in the 5GC 210 can be functionally viewed as a control plane function provided by an access and mobility management function (AMF) 264, and a user plane function provided by a user plane function (UPF) 262, which operate in conjunction to form a core network (i.e., 5GC 260). The functions of the AMF 264 include: registration management, connection management, reachability management, mobility management, lawful interception, transmission of session management (SM) messages between one or more UEs 204 (e.g., any UE described herein) and a session management function (SMF) 266, a transparent proxy service for routing SM messages, access authentication and access authorization, transmission of short message service (SMS) messages between the UE 204 and a short message service function (SMSF) (not shown), and a security anchor function (SEAF). The AMF 264 also interacts with an authentication server function (AUSF) (not shown) and the UE 204, and receives an intermediate key established as a result of the UE 204 authentication process. In the case of authentication based on the UMTS (Universal Mobile Telecommunications System) Subscriber Identity Module (USIM), the AMF 264 retrieves security material from the AUSF. The functionality of the AMF 264 also includes security context management (SCM). The SCM receives keys from the SEAF, which it uses to derive access network-specific keys. The functionality of the AMF 264 also includes location service management for regulatory services, for the transmission of location service messages between the UE 204 and the Location Management Function (LMF) 270 (which acts as a location server 230), for the transmission of location service messages between the NG-RAN 220 and the LMF 270, for the allocation of Evolved Packet System (EPS) bearer identifiers for interoperation with EPS, and UE 204 mobility event notifications. In addition, the AMF 264 also supports functions for non-3GPP (Third Generation Partnership Project) access networks.

[0100] The functions of UPF 262 include: acting as an anchor point for intra-RAT / inter-RAT mobility (when applicable), acting as an external protocol data unit (PDU) session point for interconnection to a data network (not shown), providing packet routing and forwarding, packet inspection, user plane policy rule enforcement (e.g., gating, redirection, traffic steering), lawful interception (user plane collection), traffic usage reporting, user plane quality of service (QoS) handling (e.g., uplink / downlink rate enforcement, reflective QoS marking in downlink), uplink traffic verification (service data flow (SDF) to QoS flow mapping), transport level packet marking in uplink and downlink, downlink packet buffering and downlink data notification triggering, and transmitting and forwarding one or more "end markers" to the source RAN node. UPF 262 may also support the delivery of location service messages between UE 204 and a location server (such as SLP 272) on the user plane.

[0101] The functions of SMF 266 include session management, UE Internet Protocol (IP) address allocation and management, selection and control of user plane functions, traffic steering configuration for routing traffic to the correct destination at UPF 262, partial control of policy enforcement and QoS, and downlink data notification. The interface through which SMF 266 communicates with AMF 264 is called the N11 interface.

[0102] Another optional aspect may include an LMF 270 that can communicate with the 5GC 260 to provide location assistance for the UE 204. The LMF 270 can be implemented as multiple separate servers (e.g., physically separate servers, different software modules on a single server, different software modules distributed across multiple physical servers, etc.), or alternatively can each correspond to a single server. The LMF 270 can be configured to support one or more location services for the UE 204, which can be connected to the LMF 270 via the core network, the 5GC 260, and / or via the Internet (not illustrated). SLP 272 may support similar functionality as LMF 270, but LMF 270 may communicate with AMF 264, NG-RAN 220, and UE 204 on a control plane (e.g., using interfaces and protocols intended to carry signaling messages rather than voice or data), and SLP 272 may communicate with UE 204 and external clients (e.g., third-party servers 274) on a user plane (e.g., using protocols intended to carry voice and / or data, such as Transmission Control Protocol (TCP) and / or IP).

[0103] Yet another optional aspect may include a third-party server 274 that may communicate with the LMF 270, SLP 272, 5GC 260 (e.g., via AMF 264 and / or UPF 262), NG-RAN 220, and / or UE 204 to obtain location information (e.g., location estimate) of the UE 204. Thus, in some cases, the third-party server 274 may be referred to as a location service (LCS) client or external client. The third-party server 274 may be implemented as multiple separate servers (e.g., physically separate servers, different software modules on a single server, different software modules distributed across multiple physical servers, etc.), or may alternatively each correspond to a single server.

[0104] The user plane interface 263 and the control plane interface 265 connect the 5GC 260, and specifically the UPF 262 and the AMF 264, respectively, to one or more gNBs 222 and / or ng-eNBs 224 in the NG-RAN 220. The interface between the gNB 222 and / or ng-eNB 224 and the AMF 264 is referred to as the "N2"' interface, while the interface between the gNB 222 and / or ng-eNB 224 and the UPF 262 is referred to as the "N3" interface. The gNBs 222 and / or ng-eNBs 224 of the NG-RAN 220 may communicate directly with each other via a backhaul connection 223 referred to as an "Xn-C" interface. One or more of the gNBs 222 and / or ng-eNBs 224 may communicate with one or more UEs 204 via a wireless interface referred to as a "Uu" interface.

[0105] The functions of the gNB 222 may be divided between a gNB central unit (gNB-CU) 226, one or more gNB distributed units (gNB-DU) 228, and one or more gNB radio units (gNB-RU) 229. The gNB-CU 226 is a logical node that includes base station functions other than those specifically assigned to the gNB-DU 228, including delivery of user data, mobility control, radio access network sharing, positioning, session management, and the like. More specifically, the gNB-CU 226 generally hosts the radio resource control (RRC), service data adaptation protocol (SDAP), and packet data convergence protocol (PDCP) protocols of the gNB 222. The gNB-DU 228 is a logical node that generally hosts the radio link control (RLC) and medium access control (MAC) layers of the gNB 222. Its operation is controlled by the gNB-CU 226. One gNB-DU 228 may support one or more cells, and one cell is supported by only one gNB-DU 228. The interface 232 between the gNB-CU 226 and one or more gNB-DUs 228 is referred to as the "F1" interface. The physical (PHY) layer functions of the gNB 222 are typically hosted by one or more independent gNB-RUs 229, which perform functions such as power amplification and signal transmission / reception. The interface between the gNB-DU 228 and the gNB-RU 229 is referred to as the "Fx"' interface. Therefore, the UE 204 communicates with the gNB-CU 226 via the RRC layer, SDAP layer, and PDCP layer, communicates with the gNB-DU 228 via the RLC layer and MAC layer, and communicates with the gNB-RU 229 via the PHY layer.

[0106] The deployment of a communication system (such as a 5G NR system) can be arranged with various components or constituent parts in a variety of ways. In a 5G NR system or network, a network node, a network entity, a mobility element of a network, a RAN node, a core network node, a network element or a network equipment (such as a base station or one or more units (or one or more components) performing base station functions) can be implemented in an aggregated or decomposed architecture. For example, a base station (such as a Node B (NB), an evolved NB (eNB), an NR base station, a 5G NB, an access point (AP), a transmit receive point (TRP) or a cell, etc.) can be implemented as an aggregated base station (also known as a stand-alone base station or a single-chip base station) or a decomposed base station.

[0107] The aggregated base station can be configured to utilize a radio protocol stack physically or logically integrated within a single RAN node. The decomposed base station can be configured to utilize a protocol stack physically or logically distributed between two or more units, such as one or more central or centralized units (CU), one or more distributed units (DU), or one or more radio units (RU). In some aspects, the CU can be implemented within a RAN node, and one or more DUs can be co-located with the CU, or alternatively, can be geographically or virtually distributed in one or more other RAN nodes. The DU can be implemented to communicate with one or more RUs. Each of the CU, DU, and RU can also be implemented as a virtual unit, namely a virtual central unit (VCU), a virtual distributed unit (VDU), or a virtual radio unit (VRU).

[0108] Base station type operations or network designs may take into account the aggregated nature of base station functions. For example, a disaggregated base station may be used in an integrated access backhaul (IAB) network, an open radio access network (O-RAN (network configurations such as those initiated by the O-RAN Alliance)), or a virtualized radio access network (vRAN, also known as a cloud radio access network (C-RAN)). Decomposition may include distributing functions across two or more units at various physical locations, as well as virtually distributing the functions of at least one unit, which may enable flexibility in network design. Various units of a disaggregated base station or disaggregated RAN architecture may be configured for wired or wireless communication with at least one other unit.

[0109] Figure 2CAn example disaggregated base station architecture 250 is illustrated in accordance with aspects of the present disclosure. The disaggregated base station architecture 250 may include one or more central units (CUs) 280 (e.g., gNB-CUs 226), which may communicate directly with a core network 267 (e.g., 5GC 210, 5GC 260) via a backhaul link, or indirectly with the core network 267 through one or more disaggregated base station units, such as a near real-time (near-RT) RAN intelligent controller (RIC) 259 via an E2 link or a non-real-time (non-RT) RIC 257 associated with a service management and orchestration (SMO) framework 255, or both. The CU 280 may communicate with one or more distributed units (DUs) 285 (e.g., gNB-DUs 228) via respective midhaul links, such as an F1 interface. The DUs 285 may communicate with one or more radio units (RUs) 287 (e.g., gNB-RUs 229) via respective fronthaul links. The RU 287 can communicate with a corresponding UE 204 via one or more radio frequency (RF) access links. In some implementations, a UE 204 can be served by multiple RUs 287 simultaneously.

[0110] Each of the units (i.e., CU 280, DU 285, RU 287, and near-RT RIC 259, non-RT RIC 257, and SMO framework 255) may include or be coupled to one or more interfaces configured to receive or send signals, data, or information (collectively referred to as signals) via a wired or wireless transmission medium. Each of these units or an associated processor or controller that provides instructions to the communication interface of these units may be configured to communicate with one or more of the other units via a transmission medium. For example, these units may include a wired interface configured to receive or send signals to one or more of the other units via a wired transmission medium. Additionally, these units may include a wireless interface that may include a receiver, a transmitter, or a transceiver (such as a radio frequency (RF) transceiver) that is configured to receive or send signals or both to one or more of the other units on a wireless transmission medium.

[0111] In some aspects, CU 280 may host one or more higher-layer control functions. Such control functions may include radio resource control (RRC), PDCP, service data adaptation protocol (SDAP), etc. Each control function may be implemented using an interface configured to communicate signals with other control functions hosted by CU 280. CU 280 may be configured to handle user plane functions (i.e., central unit-user plane (CU-UP)), control plane functions (i.e., central unit-control plane (CU-CP)), or a combination thereof. In some specific implementations, CU 280 may be logically divided into one or more CU-UP units and one or more CU-CP units. When implemented in an O-RAN configuration, the CU-UP unit may communicate bidirectionally with the CU-CP unit via an interface (such as an E1 interface). As needed, CU 280 may be implemented to communicate with DU 285 for network control and signaling.

[0112] DU 285 may correspond to a logical unit that includes one or more base station functions for controlling the operation of one or more RU287. In some aspects, DU 285 may host one or more of a radio link control (RLC) layer, a medium access control (MAC) layer, and one or more high physical (PHY) layers (such as modules for forward error correction (FEC) coding and decoding, scrambling, modulation and demodulation, etc.) at least in part according to a functional split such as defined by the Third Generation Partnership Project (3GPP). In some aspects, DU 285 may further host one or more low PHY layers. Each layer (or module) may be implemented using an interface that is configured to communicate signals with other layers (and modules) hosted by DU 285 or with control functions hosted by CU280.

[0113] The lower layer functions may be implemented by one or more RUs 287. In some deployments, the RU 287 controlled by the DU 285 may correspond to a logical node that hosts RF processing functions or low PHY layer functions (such as performing fast Fourier transform (FFT), inverse FFT (iFFT), digital beamforming, physical random access channel (PRACH) extraction and filtering, etc.), or both, based at least in part on functional partitioning (such as lower layer functional partitioning). In such an architecture, the RU 287 may be implemented to handle over-the-air (OTA) communications with one or more UEs 204. In some specific implementations, real-time and non-real-time aspects of control plane communications and user plane communications with the RU 287 may be controlled by the corresponding DU 285. In some scenarios, this configuration may enable the implementation of the DU 285 and CU 280 in a cloud-based RAN architecture (such as a vRAN architecture).

[0114] The SMO framework 255 may be configured to support RAN deployment and provisioning of non-virtualized network elements and virtualized network elements. For non-virtualized network elements, the SMO framework 255 may be configured to support the deployment of dedicated physical resources for RAN coverage requirements, which may be managed via an operation and maintenance interface (such as an O1 interface). For virtualized network elements, the SMO framework 255 may be configured to interact with a cloud computing platform (such as an open cloud (O-Cloud) 269) to perform network element lifecycle management (such as instantiating virtualized network elements) via a cloud computing platform interface (such as an O2 interface). Such virtualized network elements may include, but are not limited to, CU 280, DU 285, RU 287, and near-RT RIC 259. In some specific implementations, the SMO framework 255 may communicate with hardware aspects of the 4G RAN (such as an open eNB (O-eNB) 261) via the O1 interface. In addition, in some specific implementations, the SMO framework 255 may communicate directly with one or more RUs 287 via the O1 interface. The SMO framework 255 may also include a non-RT RIC 257 configured to support the functionality of the SMO framework 255 .

[0115] The non-RT RIC 257 may be configured to include logic functions that enable non-real-time control and optimization of RAN elements and resources, artificial intelligence / machine learning (AI / ML) workflows including model training and updating, or policy-based guidance of applications / features in the near-RT RIC 259. The non-RTRIC 257 may be coupled to or in communication with the near-RT RIC 259 (such as via an A1 interface). The near-RT RIC 259 may be configured to include logic functions that enable near-real-time control and optimization of RAN elements and resources via data collection and actions through an interface (such as via an E2 interface) that connects one or more CUs 280, one or more DUs 285, or both, and the O-eNB with the near-RT RIC 259.

[0116] In some implementations, in order to generate an AI / ML model to be deployed in the near-RT RIC 259, the non-RT RIC 257 may receive parameters or external enrichment information from an external server. Such information may be utilized by the near-RT RIC 259 and may be received from a non-network data source or from a network function at the SMO framework 255 or the non-RT RIC 257. In some examples, the non-RT RIC 257 or the near-RT RIC 259 may be configured to adjust RAN behavior or performance. For example, the non-RT RIC 257 may monitor long-term trends and patterns of performance and employ AI / ML models to perform corrective actions through the SMO framework 255 (such as via reconfiguration of O1) or via the creation of RAN management policies (such as A1 policies).

[0117] Figure 3A , Figure 3B and Figure 3C The example may be incorporated into a UE 302 (which may correspond to any UE described herein, including the electronic device 1900), a base station 304 (which may correspond to any base station described herein), and a network entity 306 (which may correspond to or embody any network function described herein, including the location server 230 and the LMF 270 and the electronic device 2000, or alternatively may be independent of Figure 2A and Figure 2B Several example components (represented by corresponding blocks) in the NG-RAN 220 and / or 5GC 210 / 260 infrastructure depicted in the present disclosure, such as a dedicated network, are shown to support operations as described herein. It should be understood that these components can be implemented in different types of devices with different specific implementations (e.g., in an ASIC, in a system on a chip (SoC), etc.). The illustrated components can also be incorporated into other devices in the communication system. For example, other devices in the system may include components similar to those described for providing similar functionality, such as, but not limited to, Fig.19 One or more components of the processing system 1902, the transceiver circuit 1910, and the antenna 1912, and Fig. 20 2002 and one or more components of the network interface circuit 2010. In addition, a given device may include one or more of these components. For example, a device may include multiple transceiver components that enable the device to operate on multiple carriers and / or communicate via different technologies.

[0118] UE 302 and base station 304 each include one or more wireless wide area network (WWAN) transceivers 310 and 350, respectively, which provide means (e.g., means for transmitting, means for receiving, means for measuring, means for tuning, means for preventing transmitting, etc.) for communicating via one or more wireless communication networks (not shown), such as NR networks, LTE networks, GSM networks, etc. WWAN transceivers 310 and 350 may each be connected to one or more antennas 316 and 356, respectively, for communicating with other network nodes (such as other UEs, access points, base stations (e.g., eNBs, gNBs), etc.) via at least one designated RAT (e.g., NR, LTE, GSM, etc.) on a wireless communication medium of interest (e.g., a set of time / frequency resources in a particular spectrum). The WWAN transceivers 310 and 350 may be configured in various ways according to the specified RAT to send and encode signals 318 and 358 (e.g., messages, indications, information, etc.), and vice versa, to receive and decode signals 318 and 358 (e.g., messages, indications, information, pilots, etc.). Specifically, the WWAN transceivers 310 and 350 include: one or more transmitters 314 and 354 for sending and decoding the signals 318 and 358, respectively, and one or more receivers 312 and 352 for receiving and decoding the signals 318 and 358, respectively.

[0119] At least in some cases, the UE 302 and the base station 304 each further include one or more short-range wireless transceivers 320 and 360, respectively. The short-range wireless transceivers 320 and 360 can be connected to one or more antennas 326 and 366, respectively, and provide for communicating over the wireless communication medium of interest via at least one designated RAT (e.g., WiFi, LTE-D, The short-range wireless transceivers 320 and 360 are components (e.g., components for sending, components for receiving, components for measuring, components for tuning, components for preventing sending, etc.) for communicating with other network nodes (such as other UEs, access points, base stations, etc.) using a PC5, dedicated short-range communication (DSRC), wireless access for vehicle environments (WAVE), near field communication (NFC), ultra-wideband (UWB), etc.). The short-range wireless transceivers 320 and 360 can be configured in various ways according to the specified RAT to send and encode signals 328 and 368 (e.g., messages, indications, information, etc.), and conversely, to receive and decode signals 328 and 368 (e.g., messages, indications, information, pilots, etc.). Specifically, the short-range wireless transceivers 320 and 360 respectively include: one or more transmitters 324 and 364 for sending and decoding signals 328 and 368, respectively, and one or more receivers 322 and 362 for receiving and decoding signals 328 and 368, respectively. As a specific example, the short-range wireless transceivers 320 and 360 may be WiFi transceivers, Transceiver, and / or transceiver, NFC transceiver UWB transceiver or vehicle-to-vehicle (V2V) and / or vehicle-to-everything (V2X) transceiver.

[0120] At least in some cases, the UE 302 and the base station 304 also include satellite signal receivers 330 and 370. The satellite signal receivers 330 and 370 may be connected to one or more antennas 336 and 376, respectively, and may provide components for receiving and / or measuring signals from the NTV, including but not limited to satellite positioning / communication signals 338 and 378, respectively. In the case where the satellite signal receivers 330 and 370 are satellite positioning system receivers, the satellite positioning / communication signals 338 and 378 may be global positioning system (GPS) signals, global navigation satellite system (GLONASS) signals, Galileo signals, Beidou signals, Indian regional navigation satellite system (NAVIC), quasi-zenith satellite system (QZSS), etc. In the case where the satellite signal receivers 330 and 370 are non-terrestrial network (NTN) receivers, the satellite positioning / communication signals 338 and 378 may be communication signals (e.g., carrying control and / or user data) originating from a 5G network. Satellite signal receivers 330 and 370 may include any suitable hardware and / or software for receiving and processing satellite positioning / communication signals 338 and 378, respectively. Satellite signal receivers 330 and 370 may request appropriate information and operations from other systems and, at least in some cases, perform calculations using measurements obtained by any suitable satellite positioning system algorithm to determine the location of UE 302 and base station 304, respectively.

[0121] The base station 304 and the network entity 306 each include one or more network transceivers 380 and 390, respectively, which provide means (e.g., means for transmitting, means for receiving, etc.) for communicating with other network entities (e.g., other base stations 304, other network entities 306). For example, the base station 304 may employ one or more network transceivers 380 to communicate with other base stations 304 or network entities 306 via one or more wired or wireless backhaul links. As another example, the network entity 306 may employ one or more network transceivers 390 to communicate with one or more base stations 304 via one or more wired or wireless backhaul links, or communicate with other network entities 306 via one or more wired or wireless core network interfaces.

[0122] The transceiver may be configured to communicate over a wired or wireless link. A transceiver (whether a wired transceiver or a wireless transceiver) includes a transmitter circuit (e.g., transmitters 314, 324, 354, 364) and a receiver circuit (e.g., receivers 312, 322, 352, 362). In some implementations, the transceiver may be an integrated device (e.g., implementing the transmitter circuit and the receiver circuit in a single device), in some implementations may include separate transmitter circuits and separate receiver circuits, or in other implementations may be implemented in other ways. The transmitter circuit and the receiver circuit of a wired transceiver (e.g., network transceivers 380 and 390 in some implementations) may be coupled to one or more wired network interface ports. The wireless transmitter circuitry (e.g., transmitters 314, 324, 354, 364) may include or be coupled to multiple antennas (e.g., antennas 316, 326, 356, 366), such as antenna arrays, which allow the corresponding device (e.g., UE 302, base station 304) to perform transmit "beamforming", as described herein. Similarly, the wireless receiver circuitry (e.g., receivers 312, 322, 352, 362) may include or be coupled to multiple antennas (e.g., antennas 316, 326, 356, 366), such as antenna arrays, which allow the corresponding device (e.g., UE 302, base station 304) to perform receive beamforming, as described herein. In one aspect, the transmitter circuitry and the receiver circuitry may share the same multiple antennas (e.g., antennas 316, 326, 356, 366) so that the corresponding device can only receive or only transmit at a given time, rather than both receive and transmit at the same time. The wireless transceivers (eg, WWAN transceivers 310 and 350, short-range wireless transceivers 320 and 360) may also include a network listening module (NLM) or the like for performing various measurements.

[0123] As used herein, various wireless transceivers (e.g., transceivers 310, 320, 350, and 360 in some implementations, and network transceivers 380 and 390) and wired transceivers (e.g., network transceivers 380 and 390 in some implementations) may be generally characterized as a "transceiver," "at least one transceiver," or "one or more transceivers." Thus, whether a particular transceiver is a wired or wireless transceiver may be inferred based on the type of communication being performed. For example, backhaul communications between network devices or servers typically involve signaling via a wired transceiver, while wireless communications between a UE (e.g., UE 302) and a base station (e.g., base station 304) will typically involve signaling via a wireless transceiver.

[0124] UE 302, base station 304, and network entity 306 also include other components that can be used in conjunction with the operations disclosed herein. UE 302, base station 304, and network entity 306 include one or more processors 332, 384, and 394, respectively, for providing functions related to, for example, wireless communication, and for providing other processing functions. Thus, processors 332, 384, and 394 can provide components for processing, such as components for determining, components for calculating, components for receiving, components for sending, components for indicating, etc. In one aspect, processors 332, 384, and 394 can include, for example, one or more general-purpose processors, multi-core processors, central processing units (CPUs), ASICs, digital signal processors (DSPs), field programmable gate arrays (FPGAs), other programmable logic devices or processing circuits, or various combinations thereof.

[0125] The UE 302, the base station 304, and the network entity 306 include memory circuits implementing memories 340, 386, and 396 (e.g., each including a memory device) for maintaining information (e.g., information indicating reserved resources, thresholds, parameters, etc.). Thus, the memories 340, 386, and 396 may provide means for storing, means for retrieving, means for maintaining, etc. In some cases, the UE 302, the base station 304, and the network entity 306 may include ProSe modules 342, 388, and 398, respectively. The ProSe modules 342, 388, and 398 may be hardware circuits that are part of or coupled to the processors 332, 384, and 394, respectively, which, when executed, cause the UE 302, the base station 304, and the network entity 306 to perform the functions described herein. In other aspects, the ProSe modules 342, 388, and 398 may be external to the processors 332, 384, and 394 (e.g., as part of a modem processing system, integrated with another processing system, etc.). Alternatively, the ProSe modules 342, 388, and 398 may be memory modules stored in the memories 340, 386, and 396, respectively, which, when executed by the processors 332, 384, and 394 (or a modem processing system, another processing system, etc.), cause the UE 302, the base station 304, and the network entity 306 to perform the functions described herein. Figure 3A Possible locations of the ProSe module 342 are illustrated, which may be, for example, part of one or more WWAN transceivers 310 , the memory 340 , one or more processors 332 , or any combination thereof, or may be a standalone component. Figure 3B Possible locations of the ProSe module 388 are illustrated, which may be, for example, part of one or more WWAN transceivers 350 , the memory 386 , one or more processors 384 , or any combination thereof, or may be a standalone component. Figure 3C Possible locations of the ProSe module 398 are illustrated, which may be, for example, part of one or more network transceivers 390 , memory 396 , one or more processors 394 , or any combination thereof, or may be a standalone component.

[0126] UE 302 may include one or more sensors 344 coupled to one or more processors 332 to provide a means for sensing or detecting movement and / or orientation information that is independent of motion data derived from signals received by one or more WWAN transceivers 310, one or more short-range wireless transceivers 320, and / or satellite signal receivers 330. As an example, sensor 344 may include an accelerometer (e.g., a microelectromechanical system (MEMS) device), a gyroscope, a geomagnetic sensor (e.g., a compass), an altimeter (e.g., a barometric altimeter), and / or any other type of motion detection sensor. In addition, sensor 344 may include multiple different types of devices and combine their outputs to provide motion information. For example, sensor 344 may use a combination of a multi-axis accelerometer and an orientation sensor to provide the ability to calculate positioning in a two-dimensional (2D) and / or three-dimensional (3D) coordinate system.

[0127] In addition, the UE 302 includes a user interface 346, which provides means for providing indications to the user (e.g., audible and / or visual indications) and / or for receiving user input (e.g., when the user actuates a sensing device such as a keypad, touch screen, microphone, etc.). Although not shown, the base station 304 and the network entity 306 may also include a user interface.

[0128] Referring to the one or more processors 384 in more detail, in a downlink, IP packets from the network entity 306 may be provided to the processor 384. The one or more processors 384 may implement functions for an RRC layer, a PDCP layer, a radio link control (RLC) layer, and a medium access control (MAC) layer. One or more processors 384 may provide: RRC layer functions associated with broadcasting of system information (e.g., master information block (MIB), system information block (SIB)), RRC connection control (e.g., RRC connection paging, RRC connection establishment, RRC connection modification, and RRC connection release), inter-RAT mobility, and measurement configuration for UE measurement reporting; PDCP layer functions associated with header compression / decompression, security (encryption, decryption, integrity protection, integrity verification), and handover support functions; RLC layer functions associated with delivery of upper layer PDUs, error correction through automatic repeat request (ARQ), concatenation, segmentation and reassembly of RLC service data units (SDUs), re-segmentation of RLC data PDUs, and reordering of RLC data PDUs; and MAC layer functions associated with mapping between logical channels and transport channels, scheduling information reporting, error correction, priority handling, and logical channel prioritization.

[0129] The transmitter 354 and the receiver 352 may implement layer 1 (L1) functions associated with various signal processing functions. Layer 1, including the physical (PHY) layer, may include: error detection on the transport channel, forward error correction (FEC) coding / decoding of the transport channel, interleaving, rate matching, mapping to the physical channel, modulation / demodulation of the physical channel, and MIMO antenna processing. The transmitter 354 handles the mapping to the signal constellation based on various modulation schemes (e.g., binary phase shift keying (BPSK), quadrature phase shift keying (QPSK), M-phase shift keying (M-PSK), M-quadrature amplitude modulation (M-QAM)). The coded and modulated symbols may then be separated into parallel streams. Each stream may then be mapped to an orthogonal frequency division multiplexing (OFDM) subcarrier, multiplexed with a reference signal (e.g., a pilot) in the time and / or frequency domain, and then combined together using an inverse fast Fourier transform (IFFT) to produce a physical channel carrying a time domain OFDM symbol stream. The OFDM symbol stream is spatially pre-decoded to generate multiple spatial streams. Channel estimates from a channel estimator may be used to determine coding and modulation schemes and for spatial processing. Channel estimates may be derived from reference signals and / or channel state feedback sent by the UE 302. Each spatial stream may then be provided to one or more different antennas 356. The transmitter 354 may modulate an RF carrier with a corresponding spatial stream for transmission.

[0130] At the UE 302, the receiver 312 receives the signal through its corresponding antenna 316. The receiver 312 recovers the information modulated onto the RF carrier and provides the information to one or more processors 332. The transmitter 314 and the receiver 312 implement layer 1 functions associated with various signal processing functions. The receiver 312 can perform spatial processing on the information to recover any spatial streams destined for the UE 302. If the destination of multiple spatial streams is the UE 302, they can be combined into a single OFDM symbol stream by the receiver 312. The receiver 312 then converts the OFDM symbol stream from the time domain to the frequency domain using a fast Fourier transform (FFT). The frequency domain signal includes a separate OFDM symbol stream for each subcarrier of the OFDM signal. The symbols on each subcarrier and the reference signal are recovered and demodulated by determining the most likely signal constellation point sent by the base station 304. These soft decisions can be based on channel estimates calculated by a channel estimator. The soft decisions are then decoded and deinterleaved to recover the data and control signals originally sent by the base station 304 on the physical channel. The data and control signals are then provided to one or more processors 332, which implement layer 3 (L3) and layer 2 (L2) functions.

[0131] In the downlink, one or more processors 332 provide demultiplexing between transport and logical channels, packet reassembly, decryption, header decompression, and control signal processing to recover IP packets from the core network. One or more processors 332 are also responsible for error detection.

[0132] Similar to the functions described in conjunction with downlink transmissions performed by the base station 304, the one or more processors 332 provide: RRC layer functions associated with system information (e.g., MIB, SIB) acquisition, RRC connection, and measurement reporting; PDCP layer functions associated with header compression / decompression and security (encryption, decryption, integrity protection, integrity verification); RLC layer functions associated with transmission of upper layer PDUs, error correction through ARQ, concatenation, segmentation and reassembly of RLC SDUs, re-segmentation of RLC data PDUs, and reordering of RLC data PDUs; and MAC layer functions associated with mapping between logical channels and transport channels, multiplexing of MAC SDUs onto transport blocks (TBs), demultiplexing of MAC SDUs from TBs, scheduling information reporting, error correction through hybrid automatic repeat request (HARQ), priority handling, and logical channel prioritization.

[0133] Channel estimates derived by the channel estimator from a reference signal or feedback sent by the base station 304 may be used by the transmitter 314 to select appropriate coding and modulation schemes and to facilitate spatial processing. The spatial streams generated by the transmitter 314 may be provided to different antennas 316. The transmitter 314 may modulate an RF carrier with a corresponding spatial stream for transmission.

[0134] The uplink transmissions are processed at the base station 304 in a manner similar to that described in conjunction with the receiver functionality at the UE 302. The receiver 352 receives the signal through its respective antenna 356. The receiver 352 recovers the information modulated onto the RF carrier and provides the information to one or more processors 384.

[0135] In the uplink, one or more processors 384 provide demultiplexing between transport and logical channels, packet reassembly, decryption, header decompression, control signal processing to recover IP packets from UE 302. IP packets from one or more processors 384 may be provided to the core network. One or more processors 384 are also responsible for error detection.

[0136] For convenience, UE 302, base station 304 and / or network entity 306 may Figure 3A , Figure 3B and Figure 3C , is shown as including various components that can be configured according to the various examples described herein. However, it should be understood that the illustrated components may have different functions in different designs. Specifically, FIG. 3A to FIG. 3C Various components in are optional in alternative configurations, and various aspects include configurations that may vary due to design choice, cost, use of the device, or other considerations. For example, in Figure 3A In the case of a wearable device or a tablet computer or a PC or a laptop computer, a specific implementation of the UE 302 may omit the WWAN transceiver 310 (e.g., a wearable device or a tablet computer or a PC or a laptop computer may have Wi-Fi and / or Bluetooth capabilities but no cellular capabilities), may omit the short-range wireless transceiver 320 (e.g., only cellular, etc.), may omit the satellite signal receiver 330, may omit the sensor 344, etc. In another example, in Figure 3B In the case of a wireless network, a specific implementation of the base station 304 may omit the WWAN transceiver 350 (e.g., a Wi-Fi "hotspot" access point without cellular capabilities), or may omit the short-range wireless transceiver 360 (e.g., cellular only, etc.), or may omit the satellite signal receiver 370, etc. For the sake of brevity, illustrations of various alternative configurations are not provided herein, but will be readily apparent to those skilled in the art.

[0137] Various components of the UE 302, base station 304, and network entity 306 may be communicatively coupled to one another via data buses 334, 382, ​​and 392, respectively. In an aspect, the data buses 334, 382, ​​and 392 may form or be part of a communication interface for the UE 302, base station 304, and network entity 306, respectively. For example, where different logical entities are embodied in the same device (e.g., gNB and location server functionality incorporated into the same base station 304), the data buses 334, 382, ​​and 392 may provide for communication between the different logical entities.

[0138] Figure 3A , Figure 3B and Figure 3C The components of can be implemented in various ways. In some specific implementations, Figure 3A , Figure 3B and Figure 3CThe components may be implemented in one or more circuits, such as, for example, one or more processors and / or one or more ASICs (which may include one or more processors). Here, each circuit may use and / or be combined with at least one memory component for storing information or executable code used by the circuit to provide the function. For example, some or all of the functions represented by blocks 310 to 346 may be implemented by the processor and memory components of UE 302 (e.g., by executing appropriate codes and / or by appropriate configuration of the processor components). Similarly, some or all of the functions represented by blocks 350 to 388 may be implemented by the processor and memory components of base station 304 (e.g., by executing appropriate codes and / or by appropriate configuration of the processor components). Moreover, some or all of the functions represented by blocks 390 to 398 may be implemented by the processor and memory components of network entity 306 (e.g., by executing appropriate codes and / or by appropriate configuration of the processor components). For simplicity, various operations, actions and / or functions are described herein as being performed by "UE", "by base station", "by network entity", etc. However, it should be understood that such operations, actions and / or functions may actually be performed by specific components or combinations of components of the UE 302, base station 304, network entity 306, etc. (such as processors 332, 384, 394, transceivers 310, 320, 350 and 360, memories 340, 386 and 396, ProSe modules 342, 388 and 398, etc.).

[0139] In some designs, the network entity 306 may be implemented as a core network component. In other designs, the network entity 306 may be operated differently from a network operator or cellular network infrastructure (e.g., NG RAN 220 and / or 5GC 210 / 260). For example, the network entity 306 may be a component of a dedicated network that may be configured to communicate with the UE 302 via the base station 304 or independently of the base station 304 (e.g., via a non-cellular communication link such as WiFi).

[0140] Proximity services allow devices in close proximity to each other to communicate over a direct wireless link such as PC5, which is a short-range direct communication interface between vehicles, vulnerable road users (VRUs) (e.g., pedestrians), and roadside equipment. 5G ProSe services and their use cases include, but are not limited to, the following:

[0141] 5G ProSe Direct Discovery: Allows a UE to discover another UE using the same application. Use cases include public safety, social media, and service announcements.

[0142] Unicast mode 5G ProSe direct communication: Allows direct communication between two devices without connecting to a cellular network or other wireless network. Use cases include interactive gaming between two devices, extended reality (XR) operations between mobile devices and XR glasses, headsets or wearables, and communication between public safety personnel when the network is down.

[0143] 5G ProSe communication via 5G ProSe UE-to-Network (U2N) relay: allows the extension of ProSe direct communication onto the network. Use cases include coverage extension, such as to devices out of coverage or with very poor network connectivity, for public safety and commercial purposes.

[0144] According to one or more examples, during ProSe U2N relay operation, the relay UE processes and / or routes remote UE network traffic at layer 2 or layer 3. For layer 3 relay, the network traffic is relayed at the PDCP layer or higher, and security is implemented in a hop-by-hop security mechanism using PC5 packet PDCP security between the remote UE and the relay UE and using Uu PDCP security between the relay UE and the base station. The remote UE does not have end-to-end security with the network. Note that the same principles are applicable to protocols other than PC5 and to non-ProSe sidelink communications.

[0145] According to one or more examples, for a UE that is performing layer 3 (L3) U2N relay operations, there are two different security procedures: user plane (UP) based procedures, and control plane (CP) based procedures. These UP and CP based procedures enable a secure link between a remote UE and a relay UE to be established. The network and / or UE may implement only one or both of these types of procedures. Figure 4 , Figure 5A and Figure 5B These procedures are described in more detail in .

[0146] Figure 44 is a signaling and event diagram 400 illustrating UP-based security procedures involving L3 U2N relay. The event diagram 400 illustrates the interaction between a remote UE 402, a 5G Direct Discovery Name Management Function (DDNMF) serving the remote UE 402 (hereinafter referred to as "remote DDNMF 404"), a ProSe Key Management Function (PKMF) serving the remote UE 402 (hereinafter referred to as "remote PKMF 406"), a Home Subscriber Server (HSS) serving the remote UE 402 (hereinafter referred to as "remote HSS 408"), a UE operating as a U2N relay (hereinafter referred to as "relay UE 410"), a DDNMF serving the relay UE 410 (hereinafter referred to as "relay DDNMF 412"), and a PKMF serving the relay UE 410 (hereinafter referred to as "relay PKMF 414"). Remote DDNMF 404 , remote PKMF 406 , and remote HSS 408 are in the home network of remote UE 402 , and relay DDNMF 412 and relay PKMF 414 are in the home network of relay UE 410 .

[0147] exist Figure 4 In the illustrated example, at 416, the remote UE 402 optionally queries the remote DDNMF 404 to obtain the address of the remote PKMF 406. At 418, the remote UE 402 obtains the discovery security material from the remote PKMF 406. During 418, the remote PKMF 406 may communicate with the relay PKMF 414 as needed, for example, to obtain the discovery security material needed by the remote UE 402 to discover and connect to the relay UE 410. In some aspects, the remote PKMF 406 is configured or pre-configured to know a potential list of possible PKMFs (including the relay PKMF 412).

[0148] exist Figure 4 In the illustrated example, at 420, relay UE 410 optionally queries relay DDNMF 412 to obtain the address of relay PKMF 414. At 422, relay UE 410 obtains discovery material from relay PKMF 414.

[0149] exist Figure 4In the illustrated example, at 424, the remote UE 402 transmits a ProSe relay user key (PRUK) request to the remote PKMF 406. At 426, the remote UE 402 receives a PRUK response from the remote PKMF 406. The PRUK response includes a PRUK and a PRUK identifier (PRUK ID). The PRUK is used to derive keys, such as PC5 keys, for a secure connection between the remote UE 4042 and the relay UE 410. The PRUK is identified by its PRUK ID. In some aspects, the PRUK ID is similar to the UE ID.

[0150] exist Figure 4 In the illustrated example, at 428, the remote UE 402 performs a discovery procedure to find the relay UE 410. The remote UE 402 discovers the relay UE 410 based on a restricted discovery procedure.

[0151] exist Figure 4 In the illustrated example, the remote UE 402 establishes a secure connection with the relay UE. To this end, at 430, the remote UE 402 transmits a direct communication request to the relay UE 410 to initiate the connection establishment. In some aspects, the direct communication request includes a relay service code (RSC) and a freshness parameter. The remote UE 402 will first transmit a direct communication request including the PRUK ID received by the remote UE 402 at 426. However, if too much time has passed between 426 and 430, the PRUKID may have expired or may be otherwise invalid. In this case, the remote UE 402 may transmit a second direct communication request including a subscription concealment identifier (SUCI).

[0152] It is worth noting that both PRUK ID and SUCI include home routing information, such as a home public land mobile network (HPLMN) ID. Therefore, after the relay PKMF 414 receives the key request at 432, the relay PKMF 414 can determine the home network of the remote UE 402 based on the PRUKID or SUCI, and thus can determine the address of the remote PKMF 406.

[0153] Relay UE 410 obtains the PC5 key from remote PKMF 406 via relay PKMF 414. Figure 4In the illustrated example, at 432, the relay UE 410 forwards the information in the direct communication request to the relay PKMF 414, for example, via a key request. At 434, the relay PKMF 414 forwards the key request to the remote PKMF 406 to check whether the remote UE 402 is authorized to use the service. The remote PKMF 406 will check the PRUK ID or SUCI, RSC and other parameters received from the remote UE 402. At 436, the remote PKMF 406 queries the remote HSS 408 to obtain the Generic Bootstrapping Architecture (GBA) Push Information (GPI) or Authentication Vector (AV) for the remote UE 402. At 438, the remote PKMF 406 transmits a key response to the relay PKMF 414, which includes a PC5 key (KNRP) or other type of key, and optionally also includes a GPI (e.g., if authentication to the network is required). Thus, KNRP is used for a secure connection from remote UE 402 to relay UE 410, and GPI is used to authenticate remote UE 402 to the network that gives relay UE 410 remote UE 402 access.

[0154] At 442, the relay UE 410 transmits a direct security mode command including the PC5 key and optionally the GPI (if authentication is required) to the remote UE 402. If the PRUK ID provided to the relay UE 410 in the direct communication request at 430 is valid (i.e., correct and not expired), the PC5 key provided by the relay UE 410 will also be correct and the relay UE 410 will be successfully authorized at 444, and the remote UE 402 will report this by transmitting a direct security mode complete message to the relay UE 410 at 446. At 448, the relay UE 410 will authorize the remote UE 402, and at 450, the relay UE 410 will transmit a direct communication accept message to the remote UE 402.

[0155] If the network determines to refresh the PRUK or if the remote UE 402 does not have a valid PRUK, a new PRUK may be established based on the GPI. This allows the remote UE 402 to authenticate and establish a PC5 key with the network without interaction.

[0156] Figure 5A and Figure 5B is a signaling and event diagram illustrating portions of a CP-based security procedure 500 involving L3 U2N relays. Figure 5A and Figure 5BThe example illustrates the interaction between a remote UE 502, an access and mobility management function (AMF) serving the remote UE 502 (hereinafter referred to as the “remote AMF 504”), an authentication server function (AUSF) serving the remote UE 502 (hereinafter referred to as the “remote AUSF 506”), a unified data management (UDM) server serving the remote UE 502 (hereinafter referred to as the “remote UDM 508”), a ProSe anchor function (PAnF) serving the remote UE 502 (hereinafter referred to as the “remote PAnF 510”), a UE operating as a U2N relay (hereinafter referred to as the “relay UE 512”), and an AMF serving the relay UE 512 (hereinafter referred to as the “relay AMF 514”). The remote AMF 504, remote AUSF 506, remote UDM 508 and remote PAnF 510 are in the home network of the remote UE 502, and the relay AMF 514 is the home network of the relay UE 512. Figure 5A An example is shown where the remote UE 502 has a valid PRUK ID, and Figure 5B Examples are shown where the remote UE 502 does not have a valid PRUK ID or when a SUCI is provided instead of a PRUK ID.

[0157] exist Figure 5A In the illustrated example, at 516, remote UE 502 attaches to the network, and at 518, relay UE 512 attaches to the network. Figure 4 The illustrated 5G DDNMF supplies security material and PC5 security policy to the remote UE 502. At 520, the remote UE 502 performs a discovery procedure to find the relay UE 512. The remote UE 502 discovers the relay UE 512 based on a restricted discovery procedure.

[0158] At 522, the remote UE 502 initiates establishment of a secure connection with the relay UE 512 by transmitting a direct communication request. In some aspects, if the remote UE 502 possesses a PRUK ID, the direct communication request will include the PRUK ID, but if the remote UE 502 does not have a PRUK ID, or if the PRUK ID has expired or is invalid, the direct communication request will include a SUCI. At 524, the relay UE 512 transmits a relay key request to the relay AMF 514. The relay key request will include the PRUK ID or SUCI, and a transaction identifier (TXI). At 526, the relay AMF 514 authorizes the relay UE, for example, to determine whether the relay UE 512 can make such a request. Figure 5A In the example shown, relay UE 512 does have such authorization.

[0159] The relay AMF 514 determines the home network of the remote UE 502 based on the PRUK ID or SUCI, and thus can determine the address of the remote AUSF 506. At 528, the relay AMF 514 transmits an authentication request to the remote AUSF 506, for example, to determine whether the remote UE 502 is authorized to use the ProSe service. Figure 5A In the example shown, the remote UE 502 does have such authorization.

[0160] exist Figure 5A In the example, at 530, the remote AUSF 506 transmits a ProSe key registration request to the remote PAnF 510, the request including the PRUK ID and the RSC. At 532, the remote AUSF 506 receives a ProSe key registration response from the remote PAnF 510, the response including the PRUK. At 534, the remote AUSF 506 generates a security key (KNRP) for a secure connection between the remote UE 502 and the relay UE 512. Figure 5A In the illustrated example, the security key is a PC5 key to be used for a secure PC5 link between the remote UE 502 and the relay UE 512, but a protocol other than PC5 may be used instead. At 536, the remote AUSF 506 transmits a ProSe authentication response to the relay AMF 514, the ProSe authentication response including the security key KNRP. At 538, the relay AMF 514 forwards the security key KNRP to the relay UE 512, for example in a relay key response message.

[0161] At 540, the relay UE 512 transmits a direct security mode command to the remote UE 502, indicating success. At 542, the remote UE 502 generates its own copy of the security key KNRP. At 544, the remote UE 502 transmits a direct security mode complete message to the relay UE 512. At 546, the relay UE 512 transmits a direct communication accept message to the remote UE 502. In this way, a secure connection between the remote UE 502 and the relay UE 512 is established.

[0162] exist Figure 5BIn the illustrated example, the direct communication request at 522, the relay key request at 524, and the ProSe authentication request transmitted at 528 do not include a PRUK ID, but include a SUCI. In this scenario, at 548, the remote AUSF 506 queries the remote UDM 508 to obtain an authentication vector (AV). At 550, the remote AUSF 506 transmits a ProSe authentication response message to the relay AMF 514. At 552, the relay AMF 514 transmits a relay authentication request to the relay UE 512, the relay authentication request including a transaction identifier TXI. At 554 and 556, the relay UE 512 exchanges extensible authentication protocol (EAP) messages. At 558, the relay UE 512 issues a relay authentication response including TXI. At 560, the relay AMF 514 issues another ProSe authentication request to the remote AUSF 506. At 562, the remote UE 502 generates a PRUK and a PRUK ID, and at 564, the remote AUSF 506 generates its own copy of the PRUK and the PRUK ID. At 566, the remote AUSF 506 transmits a ProSe Registration Request to the remote PAnF 510, the ProSe Registration Request including the SUPI, PRUK, PRUK ID, and RSC. At 568, the remote PAnF 510 transmits a ProSe Key Registration Response to the remote AUSF 506. From here, the process continues from 534 as shown in FIG. Figure 5A shown, and therefore will not be repeated here.

[0163] Figure 6 and Figure 7 is a signaling and event diagram illustrating a process known as resynchronization, which is performed when authentication between a remote UE and a home network fails (e.g., Figure 4 444 of or in Figure 5A 554 in the above). Figure 6 illustrates a resynchronization procedure 600 using a user plane based security procedure, Figure 7 A resynchronization procedure 700 using a control plane based security procedure is illustrated.

[0164] exist Figure 6 In the example shown, the remote UE 402 receives a direct security mode command with a security key KNRP and an optional GPI from the relay UE 410 (in Figure 4 442 of ), but the authentication fails at 602, so at 604 the remote UE 402 notifies the relay UE 410 of the failure by transmitting a direct security mode failure message including a random key (RAND) and an authentication token (AUTS).

[0165] At 606, the relay UE 410 issues a key request to the relay PKMF 414, the key request including the RAND, AUTS and also including network routing information for the home network of the remote UE 402, such as the HPLMN ID of the home network. At 608, the relay PKMF 414 forwards the request to the remote PKMF 406. At 610, the relay PKMF 414 queries the remote HSS 408 to obtain the AV and / or GPI for the remote UE 402. At 612, the remote HSS 408 provides a key response to the relay PKMF 414. At 614, the relay PKMF 414 forwards the key response to the relay UE 410.

[0166] At 616, relay UE 410 issues another direct security command to remote UE 402, and this time, authorization succeeds at 618. At 620, remote UE 402 transmits a direct security mode complete message to relay UE 410.

[0167] exist Figure 7 In the example shown, the remote UE 502 receives the EAP message at 442 , but authorization fails at 702 , so the remote UE 502 notifies the relay UE 512 of the failure at 704 .

[0168] At 706, the relay UE 512 issues a key request to the relay AMF 514, the key request including network routing information for the home network of the remote UE 502, such as the HPLMN ID of the home network. At 708, the relay AMF 514 forwards the request to the remote AUSF 506. At 710, the remote AUSF 506 queries the remote UDM 508 for security information for the remote UE 502. At 712, the remote AUSF 506 provides a key response to the relay AMF 514. At 714, the relay AMF 514 forwards the key response to the relay UE 512.

[0169] At 716, relay UE 512 sends another EAP message to remote UE 502, and this time, authorization succeeds at 718. At 720, remote UE 502 notifies relay UE 512 that authentication has passed.

[0170] Note that Figure 6 At 606 in the example, the relay UE 410 is expected to provide network address information for the home network of the remote UE 402, such as the HPLMN ID as part of the key request message at 606. However, the direct security mode failure message at 604 does not include the PRUK, PRUK ID, SUCI, or any other information from which the home network address of the remote UE 402 can be derived.

[0171] Likewise, in Figure 7 At 706 in FIG. 5 , relay UE 512 is expected to provide network address information for the home network of remote UE 502, such as the HPLMN ID as part of the key request message at 706, but the EAP message at 704 does not include a PRUK, a PRUK ID, a SUCI, or any other information from which the home network address of remote UE 502 can be derived. It is not specified how relay UE 410 or relay UE 512 is assumed to know this information.

[0172] Thus, methods and systems are provided herein for providing a remote UE's Home Network Routing Information (HNRI) after an authentication failure during establishment of U2N relay communications. The HNRI may include a home network address or any other information identifying the remote UE's home network.

[0173] Fig. 8A , Figure 8B and Figure 8C is a signaling and event diagram illustrating different methods for providing home network routing information for a remote UE according to aspects of the present disclosure. FIG. 8A to FIG. 8C Each of Figure 4 The illustrated user plane based security procedures and Figure 6 Parts of the resynchronization procedure are illustrated. FIG. 8A to FIG. 8C The components in Figure 4 and Figure 6 Like numbered elements in FIG. 1 are substantially the same, and thus their corresponding descriptions will not be repeated here.

[0174] Fig. 8A A method 800 is illustrated in which a remote UE 402 provides a HNRI to a relay UE 410, which forwards the HNRI to a relay PKMF 414. Fig. 8A In the example shown, the remote UE 402 receives a direct security mode command, such as Figure 4 442, and authentication fails, such as in Figure 6 In the first option, the remote UE 402 transmits a direct security mode failure message to the relay UE 410, such as Figure 6604 of , and at 802, the HNRI is provided to the relay UE 410 in a separate message. In a second option, at 804, the HNRI may be included in a modified direct security mode failure message. However, the direct security mode failure message is not securely protected, so any device along the route can access the unencrypted payload. Regardless of the option taken, in this method, the relay UE 410 does not need to store the PRUK ID. Instead, at 806, the relay UE 410 forwards the HNRI to the relay PKMF 414 as part of the key request message. The relay PKMF 414 uses the HNRI to know where to transmit the key request at 608.

[0175] In some aspects, the HNRI may include the HPLMN ID for the remote UE 402 if the remote UE 402 does not have a valid PRUK ID or if the PRUK ID is a 64-bit string (in which case the PRUK only identifies the remote UE 402 and not the home network).

[0176] In some aspects, if the remote UE 402 has a PRUK ID in the format of a network access identifier (NAI), the HNRI may include the PRUK ID, or the HNRI may include the PRUK ID but the username portion is set to a random value or otherwise obfuscated such that the identity of the remote UE 402 cannot be determined from the HNRI (e.g., if the HNRI is listened in during transmission).

[0177] In some aspects, the use of remote PKMF 406 in Figure 4 The discovery security material received at 418 is used to protect the confidentiality and integrity of the HNRI (and optionally, the entire message in which the HNRI is sent).

[0178] Figure 8B A method 808 is illustrated in which the relay UE 410 provides the HNRI to the relay PKMF 414. Figure 8B In the illustrated example, when the relay UE 410 is Figure 4 When receiving the direct communication request at 430 of the relay UE 410, at 810, the relay UE 410 stores the HNRI associated with the remote UE 402, which the relay UE 410 can do because both the PRUK and the SUCI include a network identity and a user identity. Then, if the relay authentication fails at 602, the relay UE 410 receives a notification at 604, obtains the HNRI of the remote UE 402 at 812, and transmits the HNRI in a key request to the relay PKMF 414 at 814. The relay PKMF 414 uses the HNRI to know where to transmit the key request at 608.

[0179] Figure 8C A method 816 is illustrated in which the relay PKMF 414 stores the HNRI. Figure 8C In the illustrated example, when the relay UE 410 is Figure 4 When receiving the direct communication request at 430 of the relay UE 410, at 818, the relay UE 410 generates and stores a transaction identifier (TXI), or reuses a transaction identifier generated by the control plane process (if any). At 820, the relay UE 410 includes the TXI in the key request to the relay PKMF 414, and at 822, the relay PKMF 414 stores the mapping of the TXI to the HNRI of the remote UE 402. Then, if the relay authentication fails at 602, the relay UE 410 receives the notification at 604 and includes the TXI in the second key request to the relay PKMF 414 at 824. At 826, the relay PKMF 414 uses the TXI to obtain the HNRI of the remote UE 402. The relay PKMF 414 uses the HNRI to know where to transmit the key request at 608.

[0180] Fig. 9A , Fig. 9B and Fig. 9C is a signaling and event diagram illustrating different methods for providing home network routing information for a remote UE according to aspects of the present disclosure. 9A to 9C Each of Figure 5A and Figure 5B The illustrated user plane based security procedures and Figure 7 Parts of the resynchronization procedure are illustrated. 9A to 9C The components in Figure 5A , Figure 5B and Figure 7 Like numbered elements in FIG. 1 are substantially the same, and thus their corresponding descriptions will not be repeated here.

[0181] Fig. 9A A method 900 is illustrated in which a remote UE 502 provides a HNRI to a relay UE 512, which forwards the HNRI to a relay AMF 514. Fig. 9A In the example shown, the remote UE 502 receives an EAP message, such as Figure 5B 554, and authorization failed, such as in Figure 7 In the first option, the remote UE 502 transmits an EAP failure message to the relay UE 512, such as Figure 7, and at 902, the HNRI is provided to the relay UE 512 in a separate message. In a second option, at 904, the HNRI may be included in the modified EAP Failure message. In this method, the relay UE 512 does not need to store the PRUK ID. Instead, at 706, the relay UE 512 forwards the HNRI to the relay AMF 514 as part of the key request message. The relay AMF 514 uses the HNRI to know where to transmit the key request at 708.

[0182] In some aspects, the HNRI may include the HPLMN ID for the remote UE 502 if the remote UE 502 does not have a valid PRUK ID or if the PRUK ID is a 64-bit string (in which case the PRUK only identifies the remote UE 502 and not the home network).

[0183] In some aspects, the HNRI may include the PRUK ID if the remote UE 502 has a PRUK ID in the format of a network access identifier (NAI), or the HNRI may include the PRUK ID but with the username portion set to a random value or otherwise obfuscated such that the identity of the remote UE 502 cannot be determined from the HNRI (e.g., if the HNRI is overheard in transmission).

[0184] In some aspects, the HNRI (and optionally the entire message in which the HNRI is sent) is privacy and integrity protected using the discovery security material received by the remote UE's DDNMF or PCF.

[0185] Fig. 9B A method 906 is illustrated in which the relay UE 512 provides the HNRI to the relay AMF 514. Fig. 9B In the illustrated example, when the relay UE 512 receives the direct communication request at 522 of FIG. 5 , at 908, the relay UE 512 stores the HNRI associated with the remote UE 502, which the relay UE 512 can do because both the PRUK and the SUCI include a network identity and a user identity. Then, if the relay authentication fails at 702, the relay UE 512 receives a notification at 704, obtains the HNRI of the remote UE 502 at 910, and transmits the HNRI to the relay AMF 514 in a key request at 706. The relay AMF 514 uses the HNRI to know where to transmit the key request at 708.

[0186] Fig. 9C A method 912 is illustrated in which the relay AMF 514 stores the HNRI. Fig. 9CIn the illustrated example, when the relay UE 512 receives the direct communication request at 522 of FIG. 5 , at 914, the relay UE 512 generates and stores a transaction identifier (TXI). At 524, the relay UE 512 includes the TXI in a key request to the relay AMF 514, and at 915, the relay AMF 514 stores a mapping of the TXI to the HNRI of the remote UE 502. If the relay authentication fails at 702, the relay UE 512 receives a notification at 704 and includes the TXI in a second key request to the relay AMF 514 at 918. At 920, the relay AMF 514 uses the TXI to obtain the HNRI of the remote UE 502. The relay AMF 514 uses the HNRI to know where to transmit the key request at 708.

[0187] Fig.10 is a flow chart of an example process 1000 associated with methods and systems for providing a remote UE's HNRI after an authentication failure during establishment of U2N relay communications, performed by a remote UE in accordance with aspects of the present disclosure. In some implementations, Fig.10 One or more process blocks of may be performed by a first user equipment (UE) (e.g., UE 104). In some implementations, Fig.10 One or more process blocks of may be performed by another device or a group of devices separate from or including the UE. Additionally or alternatively, Fig.10 One or more process blocks of process 1000 may be performed by one or more components of UE 302 (such as processor 332, memory 340, WWAN transceiver 310, short-range wireless transceiver 320, satellite signal receiver 330, sensor 344, user interface 346, and ProSe module 342), any or all of which may be means for performing the operations of process 1000.

[0188] like Fig.10 As shown, process 1000 may include, at block 1010, detecting an authentication failure during establishment of a secure connection with a second UE. In some aspects, the second UE operates as a UE-to-network (U2N) relay. Means for performing the operations of block 1010 may include a processor 332, a memory 340, or a WWAN transceiver 310 of the UE 302. For example, the UE 302 may use the processor 332 to detect the authentication failure.

[0189] like Fig.10As further shown, process 1000 may include transmitting a notification of the authentication failure to the second UE and providing the second UE with home network routing information (HNRI) for an authentication node within the home network of the first UE, at block 1020. Means for performing the operations of block 1020 may include processor 332, memory 340, or WWAN transceiver 310 of UE 302. For example, UE 302 may transmit a notification of the authentication failure to the second UE and use transmitter 314 to provide the HNRI to the second UE.

[0190] In some aspects, detecting an authentication failure during establishing a secure connection with the second UE includes detecting an authentication failure during establishing a secure connection with the second UE operating as a U2N relay.

[0191] In some aspects, detecting an authentication failure during establishing a secure connection with the second UE includes detecting an authentication failure during establishing a PC5 connection with the second UE.

[0192] In some aspects, detecting an authentication failure includes detecting a synchronization failure.

[0193] In some aspects, transmitting the notification of the authentication failure to the second UE and providing the second UE with the HNRI for the authentication node within the home network of the first UE includes transmitting the notification of the authentication failure and the HNRI in the same message.

[0194] In some aspects, transmitting notification of the authentication failure to the second UE and providing the second UE with an HNRI for an authentication node within the home network of the first UE includes transmitting notification of the authentication failure in a first message and transmitting the HNRI in a second message.

[0195] In some aspects, detecting an authentication failure includes detecting an authentication failure during a user plane security procedure.

[0196] In some aspects, detecting an authentication failure during a user plane security procedure includes: receiving a direct security mode command including an authentication challenge from a second UE; processing the authentication challenge; and detecting a failure of the authentication challenge.

[0197] In some aspects, receiving the direct security mode command includes receiving at least one of security material and a GPI for a secure connection with the second UE, and wherein processing the authentication challenge includes processing the authentication challenge included in the GPI.

[0198] In some aspects, transmitting notification of the authentication failure to the second UE includes transmitting a direct security mode failure to the second UE.

[0199] In some aspects, direct safety mode failure includes HNRI.

[0200] In some aspects, detecting an authentication failure includes detecting an authentication failure during a control plane security procedure.

[0201] In some aspects, detecting an authentication failure during a control plane security procedure includes: receiving a first EAP message including first security information from a second UE; processing an authentication challenge included in the first security information; and detecting a failure of the authentication challenge.

[0202] In some aspects, transmitting notification of the authentication failure to the second UE includes transmitting a second EAP message to the second UE.

[0203] In some aspects, the second EAP message includes the HNRI.

[0204] In some aspects, providing the HNRI to the second UE includes providing the PRUK ID or the HNRI extracted from the SUCI or the PRUK ID to the second UE.

[0205] In some aspects, providing the HNRI to the second UE includes providing the HNRI to the second UE with a user identification portion that has been modified to obscure the identity of the user.

[0206] In some aspects, providing the HNRI to the second UE includes providing the HNRI to the second UE that is confidentiality and integrity protected based on the provisioned discovery security material.

[0207] In some aspects, providing the HNRI to the second UE includes providing the second UE with the HPLMN ID of the home network of the first UE.

[0208] In some aspects, the authentication node within the home network of the first UE comprises a PKMF or an AUSF.

[0209] Process 1000 may include additional implementations, such as any single implementation or any combination of implementations described below and / or in conjunction with one or more other processes described elsewhere herein. Fig.10 An example block diagram of process 1000 is shown, but in some implementations, process 1000 may include Fig.10 The process 1000 may include more boxes, fewer boxes, different boxes, or boxes arranged in a different manner than those depicted in the process 1000. Additionally or alternatively, two or more boxes in the boxes of process 1000 may be executed in parallel.

[0210] Fig.11 is a flow chart of an example process 1100 associated with methods and systems for providing a remote UE's HNRI after an authentication failure during establishment of U2N relay communications, performed by a U2N relay UE in accordance with aspects of the present disclosure. In some implementations, Fig.11One or more process blocks of may be performed by a UE (e.g., UE 104). In some implementations, Fig.11 One or more process blocks of may be performed by another device or a group of devices separate from or including the UE. Additionally or alternatively, Fig.11 One or more process blocks of process 1100 may be performed by one or more components of UE 302 (such as processor 332, memory 340, WWAN transceiver 310, short-range wireless transceiver 320, satellite signal receiver 330, sensor 344, user interface 346, and ProSe module 342), any or all of which may be means for performing the operations of process 1100.

[0211] like Fig.11 As shown, process 1100 may include, at block 1110, receiving a notification of an authentication failure from a second UE during establishment of a secure connection between the second UE and the first UE. Means for performing the operations of block 1110 may include processor 332, memory 340, or WWAN transceiver 310 of UE 302. For example, UE 302 may use receiver 312 to receive the notification of the authentication failure.

[0212] like Fig.11 As further shown, process 1100 may include, at block 1120, determining an HNRI for an authentication node within a home network of the second UE (block 1120). Means for performing the operations of block 1120 may include processor 332, memory 340, or WWAN transceiver 310 of UE 302. Means for performing the operations of block 1120 may include processor 332, memory 340, or WWAN transceiver 310 of UE 302. For example, UE 302 may receive information via receiver 312, store information in memory 340 and retrieve information from the memory, and use processor 332 to perform other functions.

[0213] For example, in some aspects, UE 302 may determine the HNRI of an authentication node within the home network for the second UE by receiving the HNRI from the second UE prior to receiving notification of the authentication failure, storing the HNRI, and retrieving the HNRI in response to receiving notification of the authentication failure. In some aspects, UE 302 may determine the HNRI of an authentication node within the home network for the second UE by receiving the HNRI from the second UE as part of the authentication failure notification. In some aspects, UE 302 may determine the HNRI of an authentication node within the home network for the second UE by receiving the HNRI from the second UE after receiving notification of the authentication failure.

[0214] like Fig.11As further shown, process 1100 may include, at block 1130, transmitting an HNRI for an authentication node within the home network of the second UE to an authentication node within the home network of the first UE (block 1130). Means for performing the operations of block 1130 may include processor 332, memory 340, or WWAN transceiver 310 of UE 302. For example, UE 302 may use transmitter 314 to transmit the HNRI to the authentication node within the home network of the first UE.

[0215] In some aspects, receiving notification of an authentication failure includes receiving notification of a synchronization failure.

[0216] In some aspects, determining the HNRI includes: receiving the HNRI from the second UE before receiving notification of the authentication failure, storing the HNRI, and retrieving the HNRI in response to receiving notification of the authentication failure; receiving the HNRI from the second UE as part of the notification of the authentication failure; or receiving the HNRI from the second UE after receiving notification of the authentication failure.

[0217] In some aspects, receiving the HNRI from the second UE includes receiving a SUCI.

[0218] In some aspects, receiving the HNRI from the second UE includes receiving a PRUK ID.

[0219] In some aspects, the PRUK ID comprises a 64-bit string or is in NAI format.

[0220] In some aspects, receiving notification of an authentication failure during establishment of a secure connection between the second UE and the first UE includes receiving notification of an authentication failure during establishment of a PC5 connection.

[0221] In some aspects, receiving notification of an authentication failure includes receiving notification of an authentication failure during a user plane security procedure or a control plane security procedure.

[0222] In some aspects, determining the HNRI for an authentication node within the home network of the first UE includes determining the HNRI for a PKMF or an AUSF.

[0223] In some aspects, determining the HNRI comprises determining the HNRI based on the SUCI.

[0224] In some aspects, determining the HNRI comprises determining the HNRI based on the PRUK ID.

[0225] In some aspects, the PRUK ID comprises a 64-bit string or is in NAI format.

[0226] In some aspects, determining the HNRI includes determining a HPLMN ID of a home network of the second UE.

[0227] Process 1100 may include additional implementations, such as any single implementation or any combination of implementations described below and / or in conjunction with one or more other processes described elsewhere herein. Fig.11 An example block diagram of process 1100 is shown, but in some implementations, process 1100 may include Fig.11 The process 1100 may include more boxes, fewer boxes, different boxes, or boxes arranged in a different manner than those depicted in the process 1100. Additionally or alternatively, two or more boxes in the boxes of the process 1100 may be executed in parallel.

[0228] Fig.12 is a flow chart of an example process 1200 associated with methods and systems for providing a remote UE's HNRI after an authentication failure during establishment of U2N relay communications, performed by a network entity in accordance with aspects of the present disclosure. In some implementations, Fig.12 One or more process blocks of may be performed by a network entity (e.g., relay PKMF 414, relay AMF 514, relay AUSF 506). In some specific implementations, Fig.12 One or more process blocks of may be performed by another device or a group of devices separate from or including the network entity. Additionally or alternatively, Fig.12 One or more process blocks may be executed by one or more components of the network entity 306 (such as the processor 394, the memory 396, the network transceiver 390, and the ProSe module 398), any or all of which may be means for performing the operations of process 1200.

[0229] like Fig.12 As shown, process 1200 may include: at block 1210, receiving a request from a first UE for security material for a secure connection between the first UE and a second UE that is not in a home network of the first UE, the request including the TXI. The means for performing the operations of block 1210 may include a processor 394, a memory 396, or a network transceiver 390 of the network entity 306. For example, the network entity 306 may use the network transceiver 390 to receive the request for the security key.

[0230] like Fig.12 As further shown, process 1200 may include determining an HNRI for a home network of the second UE based on the TXI at block 1220. Means for performing the operations of block 1220 may include processor 394, memory 396, or network transceiver 390 of network entity 306. For example, processor 394 of network entity 306 may use the TXI to query a database for mapping the TXI to an HNRI stored in memory 396 to return the HNRI for the home network of the second UE.

[0231] like Fig.12 As further shown, process 1200 may include, at block 1230, determining an authentication node within the home network of the second UE based on the HNRI. Means for performing the operations of block 1230 may include processor 394, memory 396, or network transceiver 390 of network entity 306. For example, network entity 306 may use processor 394 to determine an authentication node within the home network of the second UE.

[0232] like Fig.12 As further shown, process 1200 may include forwarding the request to an authentication node within the home network of the second UE at block 1240. Means for performing the operations of block 1240 may include processor 394, memory 396, or network transceiver 390 of network entity 306. For example, network entity 306 may use network transceiver 390 to forward the request.

[0233] In some aspects, process 1200 includes receiving information mapping the TXI to the HNRI from the first UE, and storing a mapping between the TXI and the HNRI.

[0234] In some aspects, receiving information mapping the TXI to the HNRI includes receiving the TXI and the SUCI.

[0235] In some aspects, receiving information mapping the TXI to the HNRI includes receiving the TXI and the PRUKID.

[0236] In some aspects, the PRUK ID comprises a 64-bit string or a NAI.

[0237] In some aspects, the HNRI comprises a HPLMN ID of a home network of the second UE.

[0238] In some aspects, the authentication node within the home network of the second UE comprises a PKMF or an AUSF.

[0239] Process 1200 may include additional implementations, such as any single implementation or any combination of implementations described below and / or in conjunction with one or more other processes described elsewhere herein. Fig.12 An example block diagram of process 1200 is shown, but in some implementations, process 1200 may include Fig.12 The process 1200 may include more boxes, fewer boxes, different boxes, or boxes arranged in a different manner than those depicted in the process 1200. Additionally or alternatively, two or more boxes in the boxes of process 1200 may be executed in parallel.

[0240] Fig.13An example electronic device 1300 represented as a series of interrelated functional modules is illustrated. In one aspect, the electronic device 1300 may be a remote UE.

[0241] The electronic device 1300 may include a module 1310 for detecting an authentication failure during establishment of a secure connection with a second UE, which may operate as a U2N relay. In one aspect, the module 1310 may correspond to the processor 332, the memory 340, and / or the ProSe module 342 of the UE 302.

[0242] The electronic device 1300 may include a module 1320 for transmitting a notification of the authentication failure to the second UE in response to detecting the authentication failure and providing the second UE with an HNRI of an authentication node within the home network of the first UE. In one aspect, the module 1320 may correspond to the processor 332, the memory 340, and / or the ProSe module 342 of the UE 302.

[0243] Fig.14 An example electronic device 1400 represented as a series of interrelated functional modules is illustrated. In one aspect, the electronic device 1400 may be a U2N relay UE.

[0244] The electronic device 1400 may include a module 1410 for receiving a notification of an authentication failure during establishment of a secure connection between the second UE and the first UE from the second UE. In one aspect, the module 1410 may correspond to the processor 332, the memory 340, and / or the ProSe module 342 of the UE 302.

[0245] The electronic device 1400 may include a module 1420 for determining an HNRI of an authentication node within a home network for the second UE. In an aspect, the module 1420 may correspond to the processor 332, the memory 340, and / or the ProSe module 342 of the UE 302.

[0246] The electronic device 1400 may include a module 1430 for transmitting an HNRI for an authentication node within the home network of the second UE to the authentication node within the home network of the first UE. In one aspect, the module 1430 may correspond to the processor 332, memory 340, and / or ProSe module 342 of the UE 302.

[0247] Fig.15 An example electronic device 1500 represented as a series of interrelated functional modules is illustrated. In one aspect, the electronic device 1500 may be a network node, such as a PKMF, AMF, or AUSF.

[0248] The electronic device 1500 may include a module 1510 for receiving, from a first UE, a request for security material for a secure connection between the first UE and a second UE that is not in a home network of the first UE, the first request including the TXI. In one aspect, the module 1510 may correspond to the processor 394, the memory 396, the network transceiver 390, and the ProSe module 398 of the network entity 306.

[0249] The electronic device 1500 may include a module 1520 for determining the HNRI of the home network for the second UE based on the TXI. In an aspect, the module 1520 may correspond to the processor 394, the memory 396, the network transceiver 390, and the ProSe module 398 of the network entity 306.

[0250] The electronic device 1500 may include a module 1530 for determining an authentication node within the home network of the second UE based on the HNRI. In an aspect, the module 1530 may correspond to the processor 394, the memory 396, the network transceiver 390, and the ProSe module 398 of the network entity 306.

[0251] The electronic device 1500 may include a module 1540 for forwarding the request to an authentication node within the home network of the second UE. In an aspect, the module 1540 may correspond to the processor 394, the memory 396, the network transceiver 390, and the ProSe module 398 of the network entity 306.

[0252] Fig.16 is a flow chart of an example process 1600 associated with methods and systems for providing an HNRI of a remote UE after an authentication failure during establishment of U2N relay communications with a U2N relay UE, performed by a remote UE in accordance with aspects of the present disclosure. Fig.16 One or more process blocks of may be performed by a UE (e.g., UE 104). In some implementations, Fig.16 One or more process blocks of may be performed by another device or a group of devices separate from or including the UE. Additionally or alternatively, Fig.16 One or more process blocks of process 1600 may be performed by one or more components of UE 302 (such as processor 332, memory 340, WWAN transceiver 310, short-range wireless transceiver 320, satellite signal receiver 330, sensor 344, user interface 346, and ProSe module 342), any or all of which may be means for performing the operations of process 1600.

[0253] like Fig.16As shown, process 1600 may include: at block 1610, in response to an authentication failure during establishment of a secure connection with the second UE, transmitting a notification of an authentication failure to the second UE. The means for performing the operation of block 1610 may include the processor 332, the memory 340, or the WWAN transceiver 310 of the UE 302. For example, the UE 302 may use the transmitter 314 to transmit the notification of the authentication failure to the second UE.

[0254] like Fig.16 As further shown, process 1600 may include providing, at block 1620, an HNRI for an authentication node within the home network of the first UE to the second UE. Means for performing the operations of block 1620 may include processor 332, memory 340, or WWAN transceiver 310 of UE 302. For example, UE 302 may use transmitter 314 to provide the HNRI to the second UE.

[0255] In some aspects, detecting an authentication failure during establishment of a secure connection with a second UE comprises at least one of: detecting an authentication failure during establishment of a secure connection with a second UE operating as a U2N relay; detecting an authentication failure during establishment of a PC5 connection with the second UE; or detecting a synchronization failure.

[0256] In some aspects, transmitting notification of authentication failure to the second UE and providing the second UE with an HNRI for an authentication node within the home network of the first UE comprises: transmitting notification of authentication failure and HNRI in the same message; or transmitting notification of authentication failure in a first message and transmitting HNRI in a second message.

[0257] In some aspects, detecting an authentication failure includes detecting an authentication failure during a user plane security procedure.

[0258] In some aspects, transmitting the notification of the authentication failure to the second UE includes transmitting a direct security mode failure message to the second UE, the direct security mode failure message including the HNRI.

[0259] In some aspects, detecting an authentication failure includes detecting an authentication failure during a control plane security procedure.

[0260] In some aspects, providing the HNRI to the second UE includes providing at least one of a PRUK ID or an HNRI extracted from a SUCI or a PRUK ID to the second UE.

[0261] In some aspects, providing the HNRI to the second UE includes at least one of: modifying a user identification portion of the HNRI to obfuscate the identity of the user, and providing the HNRI with the modified user identification portion to the second UE; at least one of confidentiality protecting or integrity protecting the HNRI based on the provisioned discovery security material, and providing the confidentiality and / or integrity protected HNRI to the second UE; or providing the second UE with the HPLMN identifier of the home network of the first UE. In some aspects, the HNRI is confidentially protected based on the provisioned security material. In some aspects, the HNRI is integrity protected based on the provisioned security material. In some aspects, the HNRI is confidentiality protected and integrity protected based on the provisioned security material.

[0262] In some aspects, providing the HNRI to the second UE includes providing the second UE with a HPLMN identifier of a home network of the first UE.

[0263] In some aspects, the authentication node within the home network of the first UE comprises a PKMF or an AUSF.

[0264] Process 1600 may include additional implementations, such as any single implementation or any combination of implementations described below and / or in conjunction with one or more other processes described elsewhere herein. Fig.16 An example block diagram of process 1600 is shown, but in some implementations, process 1600 may include Fig.16 The process 1600 may include more boxes, fewer boxes, different boxes, or boxes arranged in a different manner than those depicted in the process 1600. Additionally or alternatively, two or more boxes in the boxes of process 1600 may be executed in parallel.

[0265] Fig.17 is a flow chart of an example process 1700 associated with methods and systems for providing a remote UE's HNRI after an authentication failure during establishment of a U2N relay communication with the remote UE, performed by a U2N relay UE in accordance with aspects of the present disclosure. In some implementations, Fig.17 One or more process blocks of may be performed by a UE (e.g., UE 104). In some implementations, Fig.17 One or more process blocks of may be performed by another device or a group of devices separate from or including the UE. Additionally or alternatively, Fig.17One or more process blocks of process 1700 may be performed by one or more components of UE 302 (such as processor 332, memory 340, WWAN transceiver 310, short-range wireless transceiver 320, satellite signal receiver 330, sensor 344, user interface 346, and ProSe module 342), any or all of which may be means for performing the operations of process 1700.

[0266] like Fig.17 As shown, process 1700 may include, at block 1710, receiving a notification of an authentication failure from a second UE during establishment of a secure connection between the second UE and the first UE. The means for performing the operations of block 1710 may include the processor 332, the memory 340, or the WWAN transceiver 310 of the UE 302. For example, the UE 302 may use the receiver 312 to receive the notification of the authentication failure.

[0267] like Fig.17 As further shown, process 1700 may include, at block 1720, receiving from the second UE an HNRI for a first authentication node within the home network of the second UE. Means for performing the operations of block 1720 may include processor 332, memory 340, or WWAN transceiver 310 of UE 302. For example, UE 302 may use receiver 312 to receive the HNRI.

[0268] like Fig.17 As further shown, process 1700 may include transmitting, at block 1730, an HNRI for a first authentication node within a home network of a second UE to a second authentication node within a home network of a first UE. Means for performing the operations of block 1730 may include processor 332, memory 340, or WWAN transceiver 310 of UE 302. For example, UE 302 may use transmitter 314 to transmit, to a second authentication node within a home network of a first UE, an HNRI for a first authentication node within a home network of a second UE.

[0269] In some aspects, receiving notification of an authentication failure includes receiving notification of a synchronization failure.

[0270] In some aspects, receiving the HNRI from the second UE includes receiving the HNRI from the second UE prior to receiving the notification of the authentication failure, storing the HNRI, and retrieving the HNRI in response to receiving the notification of the authentication failure.

[0271] In some aspects, the notification of the authentication failure includes the HNRI, and wherein receiving the HNRI from the second UE includes receiving the HNRI from the second UE as part of the notification of the authentication failure.

[0272] In some aspects, receiving the HNRI from the second UE includes receiving the HNRI from the second UE after receiving notification of the authentication failure.

[0273] In some aspects, receiving the HNRI from the second UE includes receiving a SUCI.

[0274] In some aspects, receiving the HNRI from the second UE includes receiving a PRUK ID.

[0275] In some aspects, the PRUK ID comprises at least one of a 64-bit string or a NAI.

[0276] In some aspects, receiving notification of an authentication failure during establishment of a secure connection between the second UE and the first UE includes receiving notification of an authentication failure during establishment of a PC5 connection.

[0277] In some aspects, receiving notification of an authentication failure includes receiving notification of an authentication failure during at least one of a user plane security procedure or a control plane security procedure.

[0278] In some aspects, determining the HNRI of the first authentication node within the home network for the second UE comprises determining the HNRI of at least one of a ProSe Key Management Function (PKMF) or an Authentication Server Function (AUSF) within the home network for the second UE.

[0279] Process 1700 may include additional implementations, such as any single implementation or any combination of implementations described below and / or in conjunction with one or more other processes described elsewhere herein. Fig.17 An example block diagram of process 1700 is shown, but in some implementations, process 1700 may include Fig.17 The process 1700 may include more boxes, fewer boxes, different boxes, or boxes arranged in a different manner than those depicted in the process 1700. Additionally or alternatively, two or more boxes in the boxes of process 1700 may be executed in parallel.

[0280] Fig.18 is a flow chart of an example process 1800 associated with methods and systems for providing a remote UE's HNRI after an authentication failure during establishment of U2N relay communications between the remote UE and a U2N relay UE in accordance with aspects of the present disclosure, performed by a network node. Fig.18 One or more process blocks of may be performed by a network entity (e.g., PKMF or AMF). In some specific implementations, Fig.18 One or more process blocks of may be performed by another device or a group of devices separate from or including the network entity. Additionally or alternatively, Fig.18One or more process blocks may be executed by one or more components of the network entity 306 (such as the processor 394, the memory 396, the network transceiver 390, and the ProSe module 398), any or all of which may be means for performing the operations of process 1800.

[0281] like Fig.18 As shown, process 1800 may include: at block 1810, receiving a request for security material for a secure connection between the first UE and a second UE having a second home network different from the first home network from a first UE of a network entity, the request including TXI. Means for performing the operations of block 1810 may include a processor 394, a memory 396, or a network transceiver 390 of the network entity 306. For example, the network entity 306 may use the network transceiver 390 to receive the request for the security material.

[0282] like Fig.18 As further shown, process 1800 may include, at block 1820, determining an HNRI for the second home network based on the TXI. Means for performing the operations of block 1820 may include the processor 394, the memory 396, or the network transceiver 390 of the network entity 306. For example, the network entity 306 may use the processor 394 to determine the HNRI for the second home network.

[0283] like Fig.18 As further shown, process 1800 may include, at block 1830, determining an authentication node within the second home network based on the HNRI for the second home network. Means for performing the operations of block 1830 may include the processor 394, the memory 396, or the network transceiver 390 of the network entity 306. For example, the network entity 306 may use the processor 394 to determine the authentication node within the second home network.

[0284] like Fig.18 As further shown, process 1800 may include forwarding the request to an authentication node within the second home network at block 1840. Means for performing the operations of block 1840 may include processor 394, memory 396, or network transceiver 390 of network entity 306. For example, network entity 306 may use network transceiver 390 to forward the request to an authentication node within the second home network.

[0285] In some aspects, process 1800 includes receiving mapping information from the first UE that maps the TXI to the HNRI for the second home network, and storing the mapping information.

[0286] In some aspects, receiving mapping information includes receiving a TXI and at least one of a SUCI or a PRUK ID.

[0287] In some aspects, the PRUK ID comprises at least one of a 64-bit string or a NAI.

[0288] In some aspects, the HNRI comprises a HPLMN identifier of the second home network.

[0289] In some aspects, the authentication node within the second home network comprises at least one of a PKMF or an AUSF.

[0290] In some aspects, the network entity includes at least one of a PKMF or an AMF.

[0291] Process 1800 may include additional implementations, such as any single implementation or any combination of implementations described below and / or in conjunction with one or more other processes described elsewhere herein. Fig.18 An example block diagram of process 1800 is shown, but in some implementations, process 1800 may include Fig.18 The process 1800 may include more boxes, fewer boxes, different boxes, or boxes arranged in a different manner than those depicted in the process 1800. Additionally or alternatively, two or more boxes in the boxes of process 1800 may be executed in parallel.

[0292] Fig.19 An example electronic device 1900 is illustrated, represented as a series of interrelated functional modules. In one aspect, the electronic device 1900 may be a remote UE or a U2N relay UE. In some aspects, the electronic device 1900 may include a processing system 1902, the processing system including a processor circuit 1904 and a memory circuit 1906, the memory circuit storing code and coupled to the processor circuit 1904 via one or more system buses 1908. In some aspects, the processing system 1902 is coupled to a transceiver circuit 1910 and one or more antennas 1912. In some aspects, the processing system 1902 includes a transmission component 1914 for managing messages and signals sent by the electronic device 1900. In some aspects, the processing system 1902 includes a receiving component 1916 for managing messages and signals received by the electronic device 1900.

[0293] In some aspects, the processing system 1902 is configured to cause the electronic device 1900 to transmit a notification of an authentication failure to the second UE in response to an authentication failure during establishment of a secure connection with the second UE. The processing system 1902 is further configured to cause the electronic device to provide the second UE with an HNRI of an authentication node within the home network of the electronic device 1900.

[0294] In other aspects, the processing system 1902 is configured to cause the electronic device 1900 to receive, from the second UE, a notification of an authentication failure during establishment of a secure connection between the second UE and the electronic device 1900. The processing system 1902 is further configured to cause the electronic device 1900 to receive, from the second UE, an HNRI of a first authentication node within a home network of the second UE. The processing system 1902 is further configured to cause the electronic device 1900 to transmit, to the second authentication node within the home network of the electronic device 1900, the HNRI of the first authentication node within the home network of the second UE.

[0295] Fig. 20 An example electronic device 2000 represented as a series of interrelated functional modules is illustrated. In one aspect, the electronic device 2000 may be a remote network entity, such as a PKMF or an AMF. In some aspects, the electronic device 2000 may include a processing system 2002, the processing system including a processor circuit 2004 and a memory circuit 2006, the memory circuit storing code and coupled to the processor circuit 2004 via one or more system buses 2008. In some aspects, the processing system 2002 is coupled to a network interface circuit 2010. In some aspects, the processing system 2002 includes a sending component 2012 for managing messages and signals sent by the electronic device 2000. In some aspects, the processing system 2002 includes a receiving component 2014 for managing messages and signals received by the electronic device 2000.

[0296] In some aspects, the processing system 2002 is configured to cause the electronic device 2000 to receive, from a first UE in a first home network of a network entity, a request for security material for a secure connection between the first UE and a second UE having a second home network different from the first home network, the request including a TXI. The processing system 2002 is further configured to determine an HNRI for the second home network based on the TXI. The processing system 2002 is further configured to determine an authentication node within the second home network based on the HNRI for the second home network. The processing system 2002 is further configured to forward the request to the authentication node within the second home network.

[0297] As should be understood, a technical advantage of the techniques disclosed herein is that these techniques specify how to provide the HNRI of the authentication node within the home network of the remote UE to the authentication node within the home network of the U2N relay UE in the event that notification of authentication failure or resynchronization is required during establishment of U2N relay communications - which is not specified by current standards.

[0298] In the above detailed description, it can be seen that different features are grouped together in each example. This disclosure should not be understood as an intention that the example embodiments have more features than the features explicitly mentioned in each embodiment. On the contrary, the various aspects of the present disclosure may include less than all the features of the disclosed individual embodiments. Therefore, the following embodiments should be considered to be incorporated into the description accordingly, wherein each embodiment itself can be used as a separate embodiment. Although each subordinate embodiment may refer to a specific combination of an embodiment in other embodiments in the embodiment, the aspects of the subordinate embodiment are not limited to a specific combination. It should be understood that other example embodiments may also include a combination of the subject matter of the subordinate embodiment with any other subordinate embodiment or independent embodiment or any feature with other subordinate embodiments and independent embodiments. The various aspects disclosed herein explicitly include these combinations, unless it is clearly expressed or can be easily inferred that it is not intended to use a specific combination (e.g., contradictory aspects, such as defining an element as both an electrical insulator and an electrical conductor). In addition, it is also expected that the various aspects of the embodiment may be included in any other independent embodiment, even if the embodiment is not directly dependent on the independent embodiment.

[0299] Specific implementation examples are described in the following numbered examples:

[0300] Embodiment 1. A method of wireless communication performed at a first user equipment (UE), the method comprising: detecting an authentication failure during establishment of a secure connection with a second UE; and in response to detecting the authentication failure, transmitting a notification of the authentication failure to the second UE; and providing the second UE with home network routing information (HNRI) for an authentication node within a home network of the first UE.

[0301] Embodiment 2. The method of embodiment 1, wherein detecting an authentication failure during establishment of a secure connection with a second UE comprises detecting an authentication failure during establishment of a secure connection with a second UE operating as a UE-to-network (U2N) relay.

[0302] Embodiment 3. The method of any one of Embodiments 1 to 2, wherein detecting the authentication failure during establishment of the secure connection with the second UE comprises detecting the authentication failure during establishment of a PC5 connection with the second UE.

[0303] Embodiment 4. The method according to any one of embodiments 1 to 3, wherein detecting the authentication failure comprises detecting a synchronization failure.

[0304] Embodiment 5. A method according to any one of embodiments 1 to 4, wherein transmitting the notification of the authentication failure to the second UE and providing the HNRI of the authentication node within the home network of the first UE to the second UE includes: transmitting the notification of the authentication failure and the HNRI in the same message.

[0305] Embodiment 6. A method according to any one of embodiments 1 to 5, wherein transmitting the notification of the authentication failure to the second UE and providing the HNRI of the authentication node within the home network of the first UE to the second UE includes: transmitting the notification of the authentication failure in a first message and transmitting the HNRI in a second message.

[0306] Embodiment 7. The method of any one of Embodiments 1 to 6, wherein detecting the authentication failure comprises detecting the authentication failure during a user plane security procedure.

[0307] Embodiment 8. The method of embodiment 7, wherein detecting the authentication failure during the user plane security procedure comprises: receiving a direct security mode command including an authentication challenge from the second UE; processing the authentication challenge; and detecting a failure of the authentication challenge.

[0308] Embodiment 9. A method according to embodiment 8, wherein receiving the direct security mode command includes receiving at least one of security material and a generic bootstrapping architecture (GBA) push information (GPI) for the secure connection with the second UE, and wherein processing the authentication challenge includes processing the authentication challenge included in the GPI.

[0309] Embodiment 10. The method of any one of Embodiments 7 to 9, wherein transmitting the notification of the authentication failure to the second UE comprises transmitting a direct security mode failure to the second UE.

[0310] Embodiment 11. The method of embodiment 10, wherein the direct safety mode failure comprises the HNRI.

[0311] Embodiment 12. The method of any one of Embodiments 1 to 11, wherein detecting the authentication failure comprises detecting the authentication failure during a control plane security procedure.

[0312] Embodiment 13. A method according to embodiment 12, wherein detecting the authentication failure during the control plane security procedure includes: receiving a first extensible authentication protocol (EAP) message including first security information from the second UE; processing an authentication challenge included in the first security information; and detecting a failure of the authentication challenge.

[0313] Embodiment 14. The method of any one of Embodiments 12 to 13, wherein transmitting the notification of the authentication failure to the second UE comprises transmitting a second EAP message to the second UE.

[0314] Embodiment 15. The method of Embodiment 14, wherein the second EAP message includes the HNRI.

[0315] Embodiment 16. The method of any one of Embodiments 1 to 15, wherein providing the HNRI to the second UE comprises providing a ProSe Relay User Key (PRUK) identifier (PRUK ID) or an HNRI extracted from a SUCI or a PRUK ID to the second UE.

[0316] Embodiment 17. The method of any one of Embodiments 1 to 16, wherein providing the HNRI to the second UE comprises providing the HNRI to the second UE with a user identification portion that has been modified to obscure the identity of a user.

[0317] Embodiment 18. The method of any one of Embodiments 1 to 17, wherein providing the HNRI to the second UE comprises providing the HNRI to the second UE that is confidentiality and integrity protected based on provisioned discovery security material.

[0318] Embodiment 19. The method of any one of Embodiments 1 to 18, wherein providing the HNRI to the second UE comprises providing the second UE with a Home Public Land Mobile Network (HPLMN) identifier of the home network of the first UE.

[0319] Embodiment 20. A method according to any one of embodiments 1 to 19, wherein the authentication node within the home network of the first UE includes a ProSe key management function (PKMF) or an authentication server function (AUSF).

[0320] Embodiment 21. A method of wireless communication performed at a first user equipment (UE), the method comprising: receiving a notification of an authentication failure during establishment of a secure connection between the second UE and the first UE from a second UE; determining home network routing information (HNRI) of an authentication node within a home network of the second UE; and transmitting the HNRI of the authentication node within the home network of the first UE to an authentication node within the home network of the second UE.

[0321] Embodiment 22. The method according to embodiment 21, receiving the notification of the authentication failure includes receiving a notification of a synchronization failure.

[0322] Embodiment 23. A method according to any one of Embodiments 21 to 22, wherein determining the HNRI includes: receiving the HNRI from the second UE before receiving the notification of the authentication failure, storing the HNRI, and retrieving the HNRI in response to receiving the notification of the authentication failure; receiving the HNRI from the second UE as part of the notification of the authentication failure; or receiving the HNRI from the second UE after receiving the notification of the authentication failure.

[0323] Embodiment 24. The method of Embodiment 23, wherein receiving the HNRI from the second UE comprises receiving a subscription concealment identifier (SUCI).

[0324] Embodiment 25. The method of any one of Embodiments 23 to 24, wherein receiving the HNRI from the second UE comprises receiving a ProSe Relay User Key (PRUK) identifier (PRUKID).

[0325] Embodiment 26. The method of embodiment 25, wherein the PRUK ID comprises a 64-bit string or a network access identifier (NAI).

[0326] Embodiment 27. The method of any one of Embodiments 21 to 26, wherein receiving the notification of the authentication failure during establishment of the secure connection between the second UE and the first UE comprises receiving the notification of the authentication failure during establishment of a PC5 connection.

[0327] Embodiment 28. The method of any one of Embodiments 21 to 27, wherein receiving the notification of the authentication failure comprises receiving the notification of the authentication failure during a user plane security procedure or a control plane security procedure.

[0328] Embodiment 29. A method according to any one of Embodiments 21 to 28, wherein determining the HNRI for the authentication node within the home network of the first UE includes determining the HNRI for a ProSe key management function (PKMF) or an authentication server function (AUSF).

[0329] Embodiment 30. The method of any one of Embodiments 21 to 29, wherein determining the HNRI comprises determining the HNRI based on a subscription concealed identifier (SUCI).

[0330] Embodiment 31. The method of any one of Embodiments 21 to 30, wherein determining the HNRI comprises determining the HNRI based on a ProSe Relay User Key (PRUK) identifier (PRUK ID).

[0331] Embodiment 32. The method of embodiment 31, wherein the PRUKID comprises a 64-bit string or a network access identifier (NAI).

[0332] Embodiment 33. The method of any one of Embodiments 21 to 32, wherein determining the HNRI comprises determining a Home Public Land Mobile Network (HPLMN) identifier of the home network of the second UE.

[0333] Embodiment 34. A method for wireless communication, the method comprising: at a network entity: receiving a request for security material for a secure connection between a first UE in a home network of the network entity and a second UE that is not in the home network of the first UE, the first request comprising a transaction identifier (TXI); determining an HNRI for the home network of the second UE based on the TXI; determining an authentication node within the home network of the second UE based on the HNRI; and forwarding the request to the authentication node within the home network of the second UE.

[0334] Embodiment 35. The method according to embodiment 34 further includes: before receiving the request for security material: receiving information mapping the TXI to the HNRI from the first UE; and storing the mapping between the TXI and the HNRI.

[0335] Embodiment 36. The method of Embodiment 35, wherein receiving the information mapping the TXI to the HNRI comprises receiving the TXI and a subscriber concealed identifier (SUCI).

[0336] Embodiment 37. The method of any one of Embodiments 35 to 36, wherein receiving the information mapping the TXI to the HNRI comprises receiving the TXI and a ProSe Relay User Key (PRUK) identifier (PRUK ID).

[0337] Embodiment 38. The method of embodiment 37, wherein the PRUKID comprises a 64-bit string or a network access identifier (NAI).

[0338] Embodiment 39. The method of any one of Embodiments 35 to 38, wherein the HNRI comprises a Home Public Land Mobile Network (HPLMN) identifier of the home network of the second UE.

[0339] Embodiment 40. A method according to any one of Embodiments 34 to 39, wherein the authentication node within the home network of the second UE includes a ProSe key management function (PKMF) or an authentication server function (AUSF).

[0340] Embodiment 41. A first user equipment (UE), comprising: a memory; and at least one processor, the at least one processor being coupled to the memory, the memory and the at least one processor being configured to: detect an authentication failure during establishment of a secure connection with a second UE; and in response to detecting the authentication failure, transmit a notification of the authentication failure to the second UE; and provide the second UE with home network routing information (HNRI) for an authentication node within a home network of the first UE.

[0341] Embodiment 42. A first UE according to embodiment 41, wherein in order to detect an authentication failure during establishment of a secure connection with a second UE, the memory and the at least one processor are configured to detect an authentication failure during establishment of a secure connection with a second UE operating as a UE-to-network (U2N) relay.

[0342] Embodiment 43. A first UE according to any one of Embodiments 41 to 42, wherein in order to detect the authentication failure during establishment of the secure connection with the second UE, the memory and the at least one processor are configured to detect the authentication failure during establishment of a PC5 connection with the second UE.

[0343] Embodiment 44. The first UE of any one of Embodiments 41 to 43, wherein to detect the authentication failure, the memory and the at least one processor are configured to detect a synchronization failure.

[0344] Embodiment 45. A first UE according to any one of embodiments 41 to 44, wherein in order to transmit the notification of the authentication failure to the second UE and provide the HNRI of the authentication node within the home network of the first UE to the second UE, the memory and the at least one processor are configured to transmit the notification of the authentication failure and the HNRI in the same message.

[0345] Embodiment 46. A first UE according to any one of embodiments 41 to 45, wherein in order to transmit the notification of the authentication failure to the second UE and provide the HNRI of the authentication node within the home network of the first UE to the second UE, the memory and the at least one processor are configured to transmit the notification of the authentication failure in a first message and transmit the HNRI in a second message.

[0346] Embodiment 47. The first UE of any one of Embodiments 41 to 46, wherein to detect the authentication failure, the memory and the at least one processor are configured to detect the authentication failure during a user plane security procedure.

[0347] Embodiment 48. A first UE according to embodiment 47, wherein, in order to detect the authentication failure during the user plane security procedure, the memory and the at least one processor are configured to: receive a direct security mode command including an authentication challenge from the second UE; process the authentication challenge; and detect the failure of the authentication challenge.

[0348] Embodiment 49. A first UE according to embodiment 48, wherein receiving the direct security mode command includes receiving at least one of security material and a generic bootstrapping architecture (GBA) push information (GPI) for the secure connection with the second UE, and wherein processing the authentication challenge includes processing the authentication challenge included in the GPI.

[0349] Embodiment 50. The first UE of any one of Embodiments 47 to 49, wherein in order to transmit the notification of the authentication failure to the second UE, the memory and the at least one processor are configured to transmit a direct security mode failure to the second UE.

[0350] Embodiment 51. The first UE of Embodiment 50, wherein the direct security mode failure comprises the HNRI.

[0351] Embodiment 52. The first UE of any one of Embodiments 41 to 51, wherein to detect the authentication failure, the memory and the at least one processor are configured to detect the authentication failure during a control plane security procedure.

[0352] Embodiment 53. A first UE according to embodiment 52, wherein, in order to detect the authentication failure during the control plane security procedure, the memory and the at least one processor are configured to: receive a first extensible authentication protocol (EAP) message including first security information from the second UE; process an authentication challenge included in the first security information; and detect a failure of the authentication challenge.

[0353] Embodiment 54. The first UE of any one of Embodiments 52 to 53, wherein in order to transmit the notification of the authentication failure to the second UE, the memory and the at least one processor are configured to transmit a second EAP message to the second UE.

[0354] Embodiment 55. The first UE of Embodiment 54, wherein the second EAP message includes the HNRI.

[0355] Embodiment 56. A first UE according to any one of embodiments 41 to 55, wherein in order to provide the HNRI to the second UE, the memory and the at least one processor are configured to provide a ProSe relay user key (PRUK) identifier (PRUK ID) or an HNRI extracted from a SUCI or a PRUK ID to the second UE.

[0356] Embodiment 57. A first UE according to any one of Embodiments 41 to 56, wherein in order to provide the HNRI to the second UE, the memory and the at least one processor are configured to provide the HNRI with a user identification portion to the second UE, and the user identification portion has been modified to obscure the identity of the user.

[0357] Embodiment 58. A first UE according to any one of Embodiments 41 to 57, wherein in order to provide the HNRI to the second UE, the memory and the at least one processor are configured to provide the second UE with a confidentiality and integrity protected HNRI based on the provisioned discovery security material.

[0358] Embodiment 59. A first UE according to any one of Embodiments 41 to 58, wherein in order to provide the HNRI to the second UE, the memory and the at least one processor are configured to provide the second UE with a Home Public Land Mobile Network (HPLMN) identifier of the home network of the first UE.

[0359] Embodiment 60. The first UE according to any one of Embodiments 41 to 59, wherein the authentication node within the home network of the first UE includes a ProSe key management function (PKMF) or an authentication server function (AUSF).

[0360] Embodiment 61. A first user equipment (UE), comprising: a memory; and at least one processor, the at least one processor being coupled to the memory, the memory and the at least one processor being configured to: receive a notification of an authentication failure from a second UE during establishment of a secure connection between the second UE and the first UE; determine home network routing information (HNRI) of an authentication node within a home network of the second UE; and transmit the HNRI of the authentication node within the home network of the first UE to an authentication node within the home network of the second UE.

[0361] Embodiment 62. The first UE of Embodiment 61, wherein in order to receive the notification of the authentication failure, the memory and the at least one processor are configured to receive a notification of a synchronization failure.

[0362] Embodiment 63. A first UE according to any one of Embodiments 61 to 62, wherein, in order to determine the HNRI, the memory and the at least one processor are configured to: receive the HNRI from the second UE before receiving the notification of the authentication failure, store the HNRI, and retrieve the HNRI in response to receiving the notification of the authentication failure; receive the HNRI from the second UE as part of the notification of the authentication failure; or receive the HNRI from the second UE after receiving the notification of the authentication failure.

[0363] Embodiment 64. The first UE of Embodiment 63, wherein to receive the HNRI from the second UE, the memory and the at least one processor are configured to receive a subscription concealment identifier (SUCI).

[0364] Embodiment 65. The first UE of any one of Embodiments 63 to 64, wherein, to receive the HNRI from the second UE, the memory and the at least one processor are configured to receive a ProSe Relay User Key (PRUK) identifier (PRUK ID).

[0365] Embodiment 66. The first UE of Embodiment 65, wherein the PRUK ID comprises a 64-bit string or a network access identifier (NAI).

[0366] Embodiment 67. A first UE according to any one of Embodiments 61 to 66, wherein in order to receive the notification of the authentication failure during establishment of the secure connection between the second UE and the first UE, the memory and the at least one processor are configured to receive the notification of the authentication failure during establishment of a PC5 connection.

[0367] Embodiment 68. A first UE according to any one of embodiments 61 to 67, wherein in order to receive the notification of the authentication failure, the memory and the at least one processor are configured to receive the notification of the authentication failure during a user plane security procedure or a control plane security procedure.

[0368] Embodiment 69. A first UE according to any one of embodiments 61 to 68, wherein in order to determine the HNRI of the authentication node within the home network for the first UE, the memory and the at least one processor are configured to determine the HNRI for a ProSe key management function (PKMF) or an authentication server function (AUSF).

[0369] Embodiment 70. The first UE of any one of Embodiments 61 to 69, wherein to determine the HNRI, the memory and the at least one processor are configured to determine the HNRI based on a subscription concealment identifier (SUCI).

[0370] Embodiment 71. The first UE of any one of Embodiments 61 to 70, wherein, to determine the HNRI, the memory and the at least one processor are configured to determine the HNRI based on a ProSe Relay User Key (PRUK) identifier (PRUKID).

[0371] Embodiment 72. The first UE of Embodiment 71, wherein the PRUK ID comprises a 64-bit string or a network access identifier (NAI).

[0372] Embodiment 73. The first UE of any one of Embodiments 61 to 72, wherein to determine the HNRI, the memory and the at least one processor are configured to determine a Home Public Land Mobile Network (HPLMN) identifier of the home network of the second UE.

[0373] Embodiment 74. A network entity comprises: a memory; and at least one processor, the at least one processor being coupled to the memory, the memory and the at least one processor being configured to: receive a request for security material for a secure connection between a first UE in a home network of the network entity and a second UE that is not in the home network of the first UE, the first request comprising a transaction identifier (TXI); determine an HNRI for the home network of the second UE based on the TXI; determine an authentication node within the home network of the second UE based on the HNRI; and forward the request to the authentication node within the home network of the second UE.

[0374] Embodiment 75. A network entity according to embodiment 74, wherein the at least one processor is further configured to, before receiving the request for security material: receive information mapping the TXI to the HNRI from the first UE; and store the mapping between the TXI and the HNRI.

[0375] Embodiment 76. The network entity of Embodiment 75, wherein to receive the information mapping the TXI to the HNRI, the memory and the at least one processor are configured to receive the TXI and a subscriber concealed identifier (SUCI).

[0376] Embodiment 77. A network entity according to any one of embodiments 75 to 76, wherein in order to receive the information mapping the TXI to the HNRI, the memory and the at least one processor are configured to receive the TXI and a ProSe relay user key (PRUK) identifier (PRUK ID).

[0377] Embodiment 78. The network entity of embodiment 77, wherein the PRUK ID comprises a 64-bit string or a network access identifier (NAI).

[0378] Embodiment 79. The network entity of any one of Embodiments 75 to 78, wherein the HNRI comprises a Home Public Land Mobile Network (HPLMN) identifier of the home network of the second UE.

[0379] Embodiment 80. A network entity according to any one of embodiments 74 to 79, wherein the authentication node within the home network of the second UE includes a ProSe key management function (PKMF) or an authentication server function (AUSF).

[0380] Embodiment 81. A network entity according to any one of embodiments 74 to 80, comprising a ProSe key management function (PKMF) or an access and mobility management function (AMF).

[0381] Embodiment 82. A first UE comprises: a component for detecting an authentication failure during establishment of a secure connection with a second UE; and a component for transmitting a notification of the authentication failure to the second UE and providing the second UE with home network routing information (HNRI) of an authentication node within a home network of the first UE in response to detecting the authentication failure.

[0382] Embodiment 83. A first UE comprises: a component for receiving a notification of an authentication failure during establishment of a secure connection between the second UE and the first UE from a second UE; a component for determining home network routing information (HNRI) of an authentication node within a home network for the second UE; and a component for transmitting the HNRI of the authentication node within the home network for the second UE to an authentication node within the home network of the first UE.

[0383] Embodiment 84. A network entity comprises: a component for receiving, from a first UE in a home network of the network entity, a request for security material for a secure connection between the first UE and a second UE that is not in the home network of the first UE, the first request comprising a transaction identifier (TXI); a component for determining an HNRI of the home network for the second UE based on the TXI; a component for determining an authentication node within the home network of the second UE based on the HNRI; and a component for forwarding the request to the authentication node within the home network of the second UE.

[0384] Embodiment 85. A non-transitory computer-readable medium storing at least one computer-executable instruction, which, when executed by a first UE, causes the first UE to: detect an authentication failure during establishment of a secure connection with a second UE; and in response to detecting the authentication failure, transmit a notification of the authentication failure to the second UE; and provide the second UE with home network routing information (HNRI) for an authentication node within the home network of the first UE.

[0385] Embodiment 86. A non-transitory computer-readable medium storing at least one computer-executable instruction, which, when executed by a first UE, causes the first UE to: receive a notification of an authentication failure from a second UE during establishment of a secure connection between the second UE and the first UE; determine home network routing information (HNRI) of an authentication node within a home network of the second UE; and transmit the HNRI of the authentication node within the home network of the first UE to an authentication node within the home network of the second UE.

[0386] Embodiment 87. A non-transitory computer-readable medium storing at least one computer-executable instruction, which, when executed by a network entity, causes the network entity to: receive a request for security material for a secure connection between a first UE in a home network of the network entity and a second UE that is not in the home network of the first UE, the first request comprising a transaction identifier (TXI); determine an HNRI for the home network of the second UE based on the TXI; determine an authentication node within the home network of the second UE based on the HNRI; and forward the request to the authentication node within the home network of the second UE.

[0387] Embodiment 88. A method for wireless communication at a first UE, comprising: in response to an authentication failure during establishment of a secure connection with a second UE, transmitting a notification of the authentication failure to the second UE; and providing the second UE with an HNRI of an authentication node within a home network of the first UE.

[0388] Embodiment 89. A method according to embodiment 88, wherein detecting the authentication failure during establishment of the secure connection with the second UE comprises at least one of the following operations: detecting the authentication failure during establishment of the secure connection with the second UE operating as a UE-to-network (U2N) relay; detecting the authentication failure during establishment of a PC5 connection with the second UE; or detecting synchronization failure.

[0389] Embodiment 90. A method according to any one of embodiments 88 to 89, wherein transmitting the notification of the authentication failure to the second UE and providing the HNRI of the authentication node within the home network of the first UE to the second UE includes: transmitting the notification of the authentication failure and the HNRI in the same message; or transmitting the notification of the authentication failure in a first message and transmitting the HNRI in a second message.

[0390] Embodiment 91. The method of any one of Embodiments 88 to 90, wherein detecting the authentication failure comprises detecting the authentication failure during a user plane security procedure.

[0391] Embodiment 92. The method of Embodiment 91, wherein transmitting the notification of the authentication failure to the second UE comprises transmitting a direct security mode failure message to the second UE, the direct security mode failure message comprising the HNRI.

[0392] Embodiment 93. A method according to any one of Embodiments 88 to 92, wherein detecting the authentication failure includes detecting the authentication failure during a control plane security procedure.

[0393] Embodiment 94. The method of any one of Embodiments 88 to 93, wherein providing the HNRI to the second UE comprises providing the second UE with at least one of: a PRUK ID; or an HNRI extracted from a SUCI or a PRUK ID.

[0394] Embodiment 95. A method according to any one of embodiments 88 to 94, wherein providing the HNRI to the second UE comprises at least one of the following operations: modifying the user identification part of the HNRI to obscure the identity of the user, and providing the HNRI with the modified user identification part to the second UE; performing at least one of confidentiality protection or integrity protection on the HNRI based on the supplied discovery security material, and providing the HNRI that has been confidentiality- and / or integrity-protected to the second UE; or providing the second UE with the HPLMN identifier of the home network of the first UE.

[0395] Embodiment 96. The method of any one of Embodiments 88 to 95, wherein providing the HNRI to the second UE comprises providing the second UE with a HPLMN identifier of the home network of the first UE.

[0396] Embodiment 97. A method according to any one of embodiments 88 to 96, wherein the authentication node within the home network of the first UE includes a PKMF or an AUSF.

[0397] Embodiment 98. A method for performing wireless communications at a first UE, comprising: receiving a notification of an authentication failure during establishment of a secure connection between the second UE and the first UE from a second UE; receiving an HNRI of a first authentication node within a home network of the second UE from the second UE; and transmitting the HNRI of the first authentication node within the home network of the second UE to a second authentication node within the home network of the first UE.

[0398] Embodiment 99. A method according to Embodiment 98, wherein receiving the notification of the authentication failure includes receiving a notification of a synchronization failure.

[0399] Embodiment 100. A method according to any one of embodiments 98 to 99, wherein receiving the HNRI from the second UE includes: receiving the HNRI from the second UE before receiving the notification of the authentication failure; storing the HNRI; and retrieving the HNRI in response to receiving the notification of the authentication failure.

[0400] Embodiment 101. A method according to any one of Embodiments 98 to 100, wherein the notification of the authentication failure includes the HNRI, and wherein receiving the HNRI from the second UE includes receiving the HNRI from the second UE as part of the notification of the authentication failure.

[0401] Embodiment 102. The method of any one of Embodiments 98 to 101, wherein receiving the HNRI from the second UE comprises receiving the HNRI from the second UE after receiving the notification of the authentication failure.

[0402] Embodiment 103. The method of any one of Embodiments 100 to 102, wherein receiving the HNRI from the second UE comprises receiving a subscription concealment identifier (SUCI).

[0403] Embodiment 104. The method of any one of Embodiments 100 to 103, wherein receiving the HNRI from the second UE comprises receiving a PRUK ID.

[0404] Embodiment 105. The method of Embodiment 104, wherein the PRUKID comprises at least one of a 64-bit string or a NAI.

[0405] Embodiment 106. A method according to any one of embodiments 98 to 105, wherein receiving the notification of the authentication failure during establishment of the secure connection between the second UE and the first UE includes receiving the notification of the authentication failure during establishment of a PC5 connection.

[0406] Embodiment 107. The method of any one of Embodiments 98 to 106, wherein receiving the notification of the authentication failure comprises receiving the notification of the authentication failure during at least one of a user plane security procedure or a control plane security procedure.

[0407] Embodiment 108. A method according to any one of Embodiments 98 to 107, wherein determining the HNRI of the first authentication node within the home network for the second UE includes determining the HNRI of at least one of a PKMF or an AUSF within the home network for the second UE.

[0408] Embodiment 109. A method for performing wireless communications at a network entity, comprising: receiving, from a first UE in a first home network of the network entity, a request for security material for a secure connection between the first UE and a second UE having a second home network different from the first home network, the request comprising a TXI; determining an HNRI for the second home network based on the TXI; determining an authentication node within the second home network based on the HNRI for the second home network; and forwarding the request to the authentication node within the second home network.

[0409] Embodiment 110. The method of embodiment 109 further includes: before receiving the request for security material: receiving mapping information from the first UE that maps the TXI to the HNRI for the second home network; and storing the mapping information.

[0410] Embodiment 111. The method of Embodiment 110, wherein receiving the mapping information comprises receiving the TXI and at least one of a SUCI or a PRUK ID.

[0411] Embodiment 112. The method of Embodiment 111, wherein the PRUKID comprises at least one of a 64-bit string or a NAI.

[0412] Embodiment 113. The method of any one of Embodiments 110 to 112, wherein the HNRI comprises a HPLMN identifier of the second home network.

[0413] Embodiment 114. The method of any one of Embodiments 109 to 113, wherein the authentication node within the second home network comprises at least one of a PKMF or an AUSF.

[0414] Embodiment 115. The method of any one of Embodiments 109 to 114, wherein the network entity comprises at least one of a PKMF or an AMF.

[0415] Embodiment 116. An apparatus for wireless communication at a first UE, comprising: one or more memories; and one or more processors, the one or more processors coupled to the one or more memories, the one or more processors configured to cause the first UE to: in response to an authentication failure during establishment of a secure connection with a second UE, transmit a notification of the authentication failure to the second UE; and provide the second UE with an HNRI of an authentication node within a home network of the first UE.

[0416] Embodiment 117. An apparatus according to embodiment 116, wherein the one or more processors configured to cause the first UE to detect the authentication failure during establishment of the secure connection with the second UE are configured to cause the first UE to perform at least one of the following operations: detecting the authentication failure during establishment of the secure connection with the second UE operating as a UE-to-network (U2N) relay; detecting the authentication failure during establishment of a PC5 connection with the second UE; or detecting a synchronization failure.

[0417] Embodiment 118. An apparatus according to any one of Embodiments 116 to 117, wherein the one or more processors configured to cause the first UE to transmit the notification of the authentication failure to the second UE and to provide the second UE with the HNRI of the authentication node within the home network of the first UE are configured to cause the first UE to: transmit the notification of the authentication failure and the HNRI in the same message; or transmit the notification of the authentication failure in a first message and transmit the HNRI in a second message.

[0418] Embodiment 119. An apparatus according to any one of Embodiments 116 to 118, wherein the one or more processors configured to cause the first UE to detect the authentication failure are configured to cause the first UE to detect the authentication failure during a user plane security procedure.

[0419] Embodiment 120. An apparatus according to embodiment 119, wherein the one or more processors configured to cause the first UE to transmit the notification of the authentication failure to the second UE are configured to cause the first UE to transmit a direct security mode failure message to the second UE, and the direct security mode failure message includes the HNRI.

[0420] Embodiment 121. An apparatus according to any one of Embodiments 116 to 120, wherein the one or more processors configured to cause the first UE to detect the authentication failure are configured to cause the first UE to detect the authentication failure during a control plane security procedure.

[0421] Embodiment 122. An apparatus according to any one of Embodiments 116 to 121, wherein the one or more processors configured to cause the first UE to provide the HNRI to the second UE are configured to provide the second UE with at least one of the following: a PRUK ID; or an HNRI extracted from a SUCI or a PRUK ID.

[0422] Embodiment 123. An apparatus according to any one of embodiments 116 to 122, wherein the one or more processors configured to cause the first UE to provide the HNRI to the second UE are configured to cause the first UE to perform at least one of the following operations: modifying the user identification part of the HNRI to obscure the identity of the user, and providing the HNRI with the modified user identification part to the second UE; performing at least one of confidentiality protection or integrity protection on the HNRI based on the supplied discovery security material, and providing the HNRI that has been confidentiality- and integrity-protected to the second UE based on the supplied discovery security material; or providing the second UE with the HPLMN identifier of the home network of the first UE.

[0423] Embodiment 124. An apparatus according to any one of Embodiments 116 to 123, wherein the one or more processors configured to cause the first UE to provide the HNRI to the second UE are configured to cause the first UE to provide the HPLMN identifier of the home network of the first UE to the second UE.

[0424] Embodiment 125. An apparatus according to any one of Embodiments 116 to 124, wherein the authentication node within the home network of the first UE includes a PKMF or an AUSF.

[0425] Embodiment 126. The apparatus of any one of Embodiments 116 to 125, further comprising one or more transceivers coupled to the one or more processors.

[0426] Embodiment 127. An apparatus according to embodiment 116, wherein the one or more processors are configured individually or collectively to cause the first UE to: transmit a notification of an authentication failure to the second UE in response to an authentication failure during establishment of a secure connection with the second UE; and provide the second UE with an HNRI of an authentication node within the home network of the first UE.

[0427] Embodiment 128. An apparatus for performing wireless communications at a first UE, comprising: one or more memories; and one or more processors, the one or more processors being coupled to the one or more memories, the one or more processors being configured to cause the first UE to: receive a notification of an authentication failure during establishment of a secure connection between the second UE and the first UE from a second UE; receive an HNRI of a first authentication node within a home network of the second UE from the second UE; and transmit the HNRI of the first authentication node within the home network of the second UE to a second authentication node within the home network of the first UE.

[0428] Embodiment 129. The apparatus of Embodiment 128, wherein the one or more processors configured to cause the first UE to receive the notification of the authentication failure are configured to cause the first UE to receive a notification of a synchronization failure.

[0429] Embodiment 130. An apparatus according to any one of Embodiments 128 to 129, wherein the one or more processors configured to cause the first UE to receive the HNRI from the second UE are configured to cause the first UE to: receive the HNRI from the second UE before receiving the notification of the authentication failure; store the HNRI; and retrieve the HNRI in response to receiving the notification of the authentication failure.

[0430] Embodiment 131. An apparatus according to any one of Embodiments 128 to 130, wherein the notification of the authentication failure includes the HNRI, and wherein the one or more processors configured to cause the first UE to receive the HNRI from the second UE are configured to cause the first UE to receive the HNRI from the second UE as part of the notification of the authentication failure.

[0431] Embodiment 132. An apparatus according to any one of Embodiments 128 to 131, wherein the one or more processors configured to cause the first UE to receive the HNRI from the second UE are configured to cause the first UE to receive the HNRI from the second UE after receiving the notification of the authentication failure.

[0432] Embodiment 133. The apparatus of any one of Embodiments 130 to 132, wherein the one or more processors configured to cause the first UE to receive the HNRI from the second UE are configured to cause the first UE to receive a subscription concealment identifier (SUCI).

[0433] Embodiment 134. The apparatus of any one of Embodiments 130 to 133, wherein the one or more processors configured to cause the first UE to receive the HNRI from the second UE are configured to cause the first UE to receive a PRUKID.

[0434] Embodiment 135. The apparatus of Embodiment 134, wherein the PRUKID comprises at least one of a 64-bit string or a NAI.

[0435] Embodiment 136. An apparatus according to any one of Embodiments 128 to 135, wherein the one or more processors configured to cause the first UE to receive the notification of the authentication failure during establishment of the secure connection between the second UE and the first UE are configured to cause the first UE to receive the notification of the authentication failure during establishment of a PC5 connection.

[0436] Embodiment 137. An apparatus according to any one of embodiments 128 to 136, wherein the one or more processors configured to cause the first UE to receive the notification of the authentication failure are configured to cause the first UE to receive the notification of the authentication failure during at least one of a user plane security procedure or a control plane security procedure.

[0437] Embodiment 138. An apparatus according to any one of Embodiments 128 to 137, wherein the one or more processors configured to enable the first UE to determine the HNRI of the first authentication node within the home network for the second UE are configured to enable the first UE to determine the HNRI of at least one of a PKMF or an AUSF within the home network for the second UE.

[0438] Embodiment 139. The apparatus of any one of Embodiments 128 to 138, further comprising one or more transceivers coupled to the one or more processors.

[0439] Embodiment 140. An apparatus according to embodiment 128, wherein the one or more processors are configured individually or collectively to cause the first UE to: receive a notification of authentication failure during establishment of a secure connection between the second UE and the first UE from a second UE; receive an HNRI of a first authentication node within a home network of the second UE from the second UE; and transmit the HNRI of the first authentication node within the home network of the second UE to a second authentication node within the home network of the first UE.

[0440] Embodiment 141. An apparatus for performing wireless communications at a network entity, comprising: one or more memories; and one or more processors, the one or more processors being coupled to the one or more memories, the one or more processors being configured to cause the network entity to: receive, from a first UE in a first home network of the network entity, a request for security material for a secure connection between the first UE and a second UE having a second home network different from the first home network, the request comprising a TXI; determine an HNRI for the second home network based on the TXI; determine an authentication node within the second home network based on the HNRI for the second home network; and forward the request to the authentication node within the second home network.

[0441] Embodiment 142. An apparatus according to embodiment 141, wherein the one or more processors are further configured to cause the network entity, before receiving the request for security material: to receive mapping information mapping the TXI to the HNRI for the second home network from the first UE; and to store the mapping information.

[0442] Embodiment 143. The apparatus of Embodiment 142, wherein the one or more processors configured to cause the network entity to receive the mapping information are configured to cause the network entity to receive the TXI and at least one of a SUCI or a PRUKID.

[0443] Embodiment 144. The apparatus of Embodiment 143, wherein the PRUK ID comprises at least one of a 64-bit string or a NAI.

[0444] Embodiment 145. The apparatus of any one of Embodiments 142 to 144, wherein the HNRI comprises a HPLMN identifier of the second home network.

[0445] Embodiment 146. The apparatus of any one of Embodiments 141 to 145, wherein the authentication node within the second home network comprises at least one of a PKMF or an AUSF.

[0446] Embodiment 147. A device according to any one of Embodiments 141 to 146, comprising at least one of a PKMF or an AMF.

[0447] Embodiment 148. The apparatus of any one of Embodiments 141 to 147, further comprising one or more transceivers coupled to the one or more processors.

[0448] Embodiment 149. An apparatus according to embodiment 141, wherein the one or more processors are configured individually or collectively to enable the network entity to: receive a request for security material for a secure connection between a first UE in a first home network of the network entity and a second UE having a second home network different from the first home network, the request comprising a TXI; determine an HNRI for the second home network based on the TXI; determine an authentication node within the second home network based on the HNRI for the second home network; and forward the request to the authentication node within the second home network.

[0449] Embodiment 150. A UE for wireless communication, comprising a processing system, the processing system including a processor circuit and a memory circuit storing code and coupled to the processor circuit, the processing system being configured to cause the UE to execute the method according to one or more of embodiments 1 to 33 and 88 to 108.

[0450] Embodiment 151. A network entity for wireless communication, comprising a processing system, the processing system including a processor circuit and a memory circuit storing code and coupled to the processor circuit, the processing system being configured to cause the UE to execute the method according to one or more of embodiments 34 to 40 and 109 to 115.

[0451] Those skilled in the art will appreciate that information and signals may be represented using any of a variety of different techniques and methods. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be mentioned throughout the above description may be represented by voltage, current, electromagnetic waves, magnetic fields or magnetic particles, light fields or optical particles, or any combination thereof.

[0452] In addition, it will be appreciated by those skilled in the art that the various exemplary logic blocks, modules, circuits and algorithmic steps described in conjunction with the various aspects disclosed herein can be implemented as electronic hardware, computer software or a combination of the two. In order to clearly illustrate this interchangeability of hardware and software, various exemplary components, frames, modules, circuits and steps have been generally described above in terms of their functions. Whether such functions are implemented as hardware or software depends on the specific application and the design constraints proposed to the entire system. Those skilled in the art can implement the described functions in different ways for each specific application, but such specific implementation decisions should not be interpreted as causing a departure from the scope of the present disclosure.

[0453] The various illustrative logical blocks, modules, and circuits described in conjunction with the various aspects disclosed herein may be implemented or performed with a general purpose processor, a digital signal processor (DSP), an ASIC, a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor may be a microprocessor, but in an alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices, such as a combination of a DSP and a microprocessor, a plurality of microprocessors, a combination of one or more microprocessors and a DSP core, or any other such configuration.

[0454] In some aspects, a single processor may perform all functions described as being performed by one or more processors. In some aspects, one or more processors may collectively perform a set of functions. For example, a first (one or more) set of processors in one or more processors may perform a first function described as being performed by one or more processors, and a second (one or more) set of processors in one or more processors may perform a second function described as being performed by one or more processors. The first set of processors and the second set of processors may be the same set of processors or may be different sets of processors. References to "one or more processors" should be understood to refer to the combination of Figure 3A , Figure 3B and Figure 3C Any one or more of the processors described, or a combination thereof Fig.19 and Fig. 20 Reference to "one or more memories" should be understood to refer to any one or more memories of the corresponding device, such as in conjunction with Figure 3A , Figure 3B and Figure 3C The memory described or combined Fig.19 and Fig. 20 For example, a function described as being performed by one or more memories may be performed by the same subset of the one or more memories or by a different subset of the one or more memories.

[0455] The methods, sequences and / or algorithms described in conjunction with the various aspects disclosed herein may be directly embodied in hardware, in a software module executed by a processor, or in a combination of the two. The software module may reside in a random access memory (RAM), a flash memory, a read-only memory (ROM), an erasable programmable ROM (EPROM), an electrically erasable programmable ROM (EEPROM), a register, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. An example storage medium is coupled to a processor so that the processor can read information from the storage medium and write information to the storage medium. In an alternative solution, the storage medium may be integral with the processor. The processor and the storage medium may reside in an ASIC. The ASIC may reside in a user terminal (e.g., UE). In an alternative solution, the processor and the storage medium may reside in a user terminal as discrete components.

[0456] In one or more example aspects, the function can be implemented in hardware, software, firmware or any combination thereof. If implemented in software, the function can be stored on a computer-readable medium or sent by a computer-readable medium as one or more instructions or codes. Computer-readable media include both computer storage media and communication media, including any medium that facilitates the sending of a computer program from one place to another. Storage media can be any available medium that can be accessed by a computer. By way of example and not limitation, such computer-readable media may include RAM, ROM, EEPROM, CD-ROM or other optical disk storage devices, disk storage devices or other magnetic storage devices or any other medium that can be used to carry or store desired program codes in the form of instructions or data structures and can be accessed by a computer. In addition, any connection is appropriately referred to as a computer-readable medium. For example, if the software is sent from a website, a server or other remote source using a coaxial cable, a fiber optic cable, a twisted pair, a digital subscriber line (DSL) or wireless technologies such as infrared, radio and microwaves, then coaxial cable, fiber optic cable, twisted pair, DSL or wireless technologies such as infrared, radio and microwaves are included in the definition of the medium. Disk and disc, as used herein, include compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disk and Blu-ray disc, where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above should also be included within the scope of computer-readable media.

[0457] Although the foregoing disclosure illustrates the exemplary aspects of the present disclosure, it should be noted that various changes and modifications may be made herein without departing from the scope of the present disclosure as defined by the appended claims. In addition, the functions, steps and / or actions of the method claims according to the various aspects of the present disclosure described herein do not need to be performed in any particular order. In addition, although the elements of the present disclosure may be described or claimed in the singular, plural forms may also be considered unless expressly stated to be limited to the singular.

Claims

1. An apparatus for wireless communication at a first user equipment (UE), the apparatus comprising: one or more memories; and one or more processors, the one or more processors being coupled to the one or more memories, the one or more processors being configured to cause the first UE to: responsive to detecting an authentication failure during establishment of a secure connection with a second UE, transmitting a notification of the authentication failure to the second UE; as well as The second UE is provided with home network routing information (HNRI) for an authentication node within a home network of the first UE.

2. The apparatus of claim 1 , wherein the one or more processors configured to cause the first UE to detect the authentication failure during establishment of the secure connection with the second UE are configured to cause the first UE to perform at least one of the following operations: detecting the authentication failure during establishment of the secure connection with the second UE operating as a UE-to-network (U2N) relay; detecting the authentication failure during establishment of a PC5 connection with the second UE; or Detection synchronization failure.

3. The apparatus of claim 1 , wherein the one or more processors configured to cause the first UE to transmit the notification of the authentication failure to the second UE and to provide the second UE with the HNRI for the authentication node within the home network of the first UE are configured to cause the first UE to: transmitting said notification of said authentication failure and said HNRI in the same message; or The notification of the authentication failure is transmitted in a first message and the HNRI is transmitted in a second message.

4. The apparatus of claim 1, wherein the one or more processors configured to cause the first UE to detect the authentication failure are configured to cause the first UE to detect the authentication failure during a user plane security procedure or during a control plane security procedure.

5. The apparatus of claim 1, wherein the one or more processors configured to cause the first UE to provide the HNRI to the second UE are configured to cause the first UE to provide at least one of the following to the second UE: ProSe Relay User Key (PRUK) identifier (PRUK ID); or HNRI extracted from SUCI or PRUK ID.

6. The apparatus of claim 1, wherein the one or more processors configured to cause the first UE to provide the HNRI to the second UE are configured to cause the first UE to perform at least one of the following operations: modifying a user identification portion of the HNRI to obscure the identity of the user, and providing the HNRI with the modified user identification portion to the second UE; at least one of confidentiality protecting or integrity protecting the HNRI based on the supplied discovery security material, and providing the confidentiality and / or integrity protected HNRI to the second UE; or A Home Public Land Mobile Network (HPLMN) identifier of the home network of the first UE is provided to the second UE.

7. The apparatus of claim 1, wherein the one or more processors configured to provide the second UE with the HNRI for the authentication node within the home network of the first UE is configured to provide the second UE with at least one of: the HNRI of a ProSe Key Management Function (PKMF) within the home network of the first UE; or The HNRI of an Authentication Server Function (AUSF) within the home network of the first UE.

8. An apparatus for wireless communication at a first user equipment (UE), the apparatus comprising: one or more memories; and one or more processors, the one or more processors being coupled to the one or more memories, the one or more processors being configured to cause the first UE to: receiving, from a second UE, a notification of an authentication failure during establishment of a secure connection between the second UE and the first UE; receiving, from the second UE, home network routing information (HNRI) for a first authentication node within a home network of the second UE; as well as The HNRI for the first authentication node within the home network of the second UE is transmitted to a second authentication node within the home network of the first UE.

9. The apparatus of claim 8, wherein the one or more processors configured to receive the notification of the authentication failure are configured to receive a notification of a synchronization failure.

10. The apparatus of claim 8, wherein the one or more processors configured to receive the HNRI from the second UE are configured to: receiving the HNRI from the second UE before receiving the notification of the authentication failure; storing the HNRI; as well as The HNRI is retrieved in response to receiving the notification of the authentication failure.

11. The apparatus of claim 8, wherein the notification of the authentication failure includes the HNRI, and wherein the one or more processors configured to receive the HNRI from the second UE are configured to receive the HNRI from the second UE as part of the notification of the authentication failure.

12. The apparatus of claim 8, wherein the one or more processors configured to receive the HNRI from the second UE are configured to receive the HNRI from the second UE after receiving the notification of the authentication failure.

13. The apparatus of claim 10, wherein the one or more processors configured to receive the HNRI from the second UE are configured to receive at least one of a subscription concealment identifier (SUCI) or a ProSe relay user key (PRUK) identifier (PRUK ID).

14. The apparatus of claim 8, wherein the one or more processors configured to receive the notification of the authentication failure during establishment of the secure connection between the second UE and the first UE are configured to receive the notification of the authentication failure during establishment of a PC5 connection.

15. The apparatus of claim 8, wherein the one or more processors configured to receive the notification of the authentication failure are configured to receive the notification of the authentication failure during at least one of a user plane security procedure or a control plane security procedure.

16. The apparatus of claim 8, wherein the one or more processors configured to determine the HNRI of the first authentication node within the home network for the second UE is configured to determine the HNRI of at least one of a ProSe Key Management Function (PKMF) within the home network of the second UE or an Authentication Server Function (AUSF) within the home network of the second UE.

17. An apparatus for wireless communication at a network entity, the apparatus comprising: one or more memories; and one or more processors, the one or more processors being coupled to the one or more memories, the one or more processors being configured to cause the network entity to: receiving a request for security material for a secure connection between a first user equipment (UE) in a first home network of the network entity and a second UE having a second home network different from the first home network, the request including a transaction identifier (TXI); determining home network routing information (HNRI) for the second home network based on the TXI; determining an authentication node within the second home network based on the HNRI for the second home network; as well as The request is forwarded to the authentication node within the second home network.

18. The apparatus of claim 17, wherein the one or more processors are further configured to, prior to receiving the request for security material: receiving, from the first UE, mapping information that maps the TXI to the HNRI for the second home network; and The mapping information is stored.

19. The apparatus of claim 18, wherein the one or more processors configured to receive the mapping information are configured to receive the TXI and at least one of a Subscriber Hidden Identifier (SUCI) or a ProSe Relay User Key (PRUK) Identifier (PRUK ID).

20. The apparatus of claim 18, wherein the one or more processors configured to determine the HNRI for the second home network are configured to determine a Home Public Land Mobile Network (HPLMN) identifier of the second home network.

21. An apparatus according to claim 17, wherein the one or more processors configured to forward the request to the authentication node within the second home network are configured to forward the request to a ProSe Key Management Function (PKMF) within the second home network or an Authentication Server Function (AUSF) within the second home network.

22. The apparatus of claim 17, wherein the network entity comprises at least one of a ProSe Key Management Function (PKMF) or an Access and Mobility Management Function (AMF).

23. A method for wireless communication at a first user equipment (UE), the method comprising: In response to an authentication failure during establishment of a secure connection with a second UE, transmitting a notification of the authentication failure to the second UE; as well as The second UE is provided with home network routing information (HNRI) for an authentication node within a home network of the first UE.

24. The method of claim 23, wherein detecting the authentication failure during establishment of the secure connection with the second UE comprises at least one of the following operations: detecting the authentication failure during establishment of the secure connection with the second UE operating as a UE-to-network (U2N) relay; detecting the authentication failure during establishment of a PC5 connection with the second UE; or Detection synchronization failure.

25. The method of claim 23, wherein transmitting the notification of the authentication failure to the second UE and providing the second UE with the HNRI for the authentication node within the home network of the first UE comprises: transmitting the notification of the authentication failure and the HNRI in the same message; Alternatively, the notification of the authentication failure is transmitted in a first message and the HNRI is transmitted in a second message.

26. The method of claim 23, wherein detecting the authentication failure comprises detecting the authentication failure during a user plane security procedure or during a control plane security procedure.

27. The method of claim 23, wherein providing the HNRI to the second UE comprises providing the second UE with at least one of: ProSe Relay User Key (PRUK) identifier (PRUK ID); or HNRI extracted from SUCI or PRUK ID.

28. The method of claim 23, wherein providing the HNRI to the second UE comprises at least one of the following operations: modifying a user identification portion of the HNRI to obscure the identity of the user, and providing the HNRI with the modified user identification portion to the second UE; at least one of confidentiality protecting or integrity protecting the HNRI based on the supplied discovery security material, and providing the confidentiality and / or integrity protected HNRI to the second UE; or A Home Public Land Mobile Network (HPLMN) identifier of the home network of the first UE is provided to the second UE.

29. The method of claim 23, wherein providing the second UE with the HNRI of the authentication node within the home network of the first UE comprises providing the second UE with the HNRI of a ProSe key management function (PKMF) within the home network of the first UE or the HNRI of an authentication server function (AUSF) within the home network of the first UE.

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