Non-access strate signaling

Abstract

The embodiment of the invention relates to a method, equipment and device for a distributed non-access layer (NAS) and a computer readable storage medium. The method comprises: providing a NAS message transmission configuration to a second device, the NAS message transmission configuration indicating at least one of a mapping between a NAS service and a radio bearer or a mapping between the NAS service and a NAS service type identifier; and routing the NAS message between the second device and a third device based at least on the NAS message transmission configuration, wherein the third device is determined from the plurality of devices based on the NAS message transmission configuration.

Description

Technical Field

[0001] Various exemplary embodiments of the present disclosure relate generally to the field of telecommunications, and more particularly, to methods, devices, apparatuses, and computer-readable storage media for non-access stratum (NAS) signaling. Background Art

[0002] In 5G New Radio (NR) networks, multiple radio bearers (RBs) are allocated for different protocol layer entities to ensure the efficiency of radio transmission. There are two main types of RBs, namely: data radio bearers (DRBs) and signaling radio bearers (SRBs). DRBs are used for user plane (U-plane) based transmissions. SRBs are RBs used for the transmission of radio resource control (RRC) messages, application layer measurement reports and / or NAS messages. In particular, RRC messages can be sent via SRB0, SRB1, or SRB3. Application layer measurement reports can be sent via SRB4. NAS messages can be sent by using a common SRB (e.g., SRB1 or SRB2). This is sufficient in 5G networks because the access and mobility management function (AMF) serves as a single entry point to the 5G core (5GC) for all NAS messages.

[0003] NAS termination is discussed for the 6G network framework, which may involve direct communication between different network functions in the 6G core network (6GCN). Therefore, there is a need to improve the routing of NAS messages to the appropriate network functions. Summary of the invention

[0004] In a first aspect of the present disclosure, a first device is provided. The first device includes at least one processor; and at least one memory storing instructions, which when executed by the at least one processor causes the first device to at least: provide a NAS message transmission configuration to a second device, the NAS message transmission configuration indicating at least one of a mapping between a NAS service and a radio bearer or a mapping between a NAS service and a NAS service type identifier; and route a NAS message between the second device and a third device based at least on the NAS message transmission configuration, wherein the third device is determined from a plurality of devices based on the NAS message transmission configuration.

[0005] In a second aspect of the present disclosure, a second device is provided. The second device includes at least one processor; and at least one memory storing instructions, which, when executed by the at least one processor, causes the second device to at least: obtain a NAS message transmission configuration from a first device, the NAS message transmission configuration indicating a mapping between a NAS service and a radio bearer or a mapping between a NAS service and a NAS service type identifier; and perform NAS message transmission between the second device and a third device via the first device based at least on the NAS message transmission configuration.

[0006] In a third aspect of the present disclosure, a method is provided. The method includes: providing a NAS message transmission configuration to a second device, the NAS message transmission configuration indicating at least one of a mapping between a NAS service and a radio bearer or a mapping between a NAS service and a NAS service type identifier; and routing a NAS message between the second device and a third device based at least on the NAS message transmission configuration, wherein the third device is determined from a plurality of devices based on the NAS message transmission configuration.

[0007] In a fourth aspect of the present disclosure, a method is provided. The method includes: acquiring a NAS message transmission configuration from a first device, the NAS message transmission configuration indicating a mapping between a NAS service and a radio bearer or a mapping between a NAS service and a NAS service type identifier; and performing NAS message transmission between a second device and a third device via the first device based at least on the NAS message transmission configuration.

[0008] In a fifth aspect of the present disclosure, a first device is provided. The first device includes: a component for providing a NAS message transmission configuration to a second device, the NAS message transmission configuration indicating at least one of a mapping between a NAS service and a radio bearer or a mapping between a NAS service and a NAS service type identifier; and a component for routing a NAS message between the second device and a third device based at least on the NAS message transmission configuration, wherein the third device is determined from a plurality of devices based on the NAS message transmission configuration.

[0009] In a sixth aspect of the present disclosure, a second device is provided. The second device includes: a component for acquiring a NAS message transmission configuration from a first device, the NAS message transmission configuration indicating a mapping between a NAS service and a radio bearer or a mapping between a NAS service and a NAS service type identifier; and a component for performing NAS message transmission between the second device and a third device via the first device based at least on the NAS message transmission configuration.

[0010] In a seventh aspect of the present disclosure, a computer-readable medium is provided, wherein the computer-readable medium includes instructions stored thereon, and the instructions are used to cause a device to at least execute the method according to the third aspect.

[0011] In an eighth aspect of the present disclosure, a computer-readable medium is provided, wherein the computer-readable medium includes instructions stored thereon, and the instructions are used to cause a device to at least execute the method according to the fourth aspect.

[0012] It should be understood that the invention summary is not intended to identify the key features or essential features of the embodiments of the present disclosure, nor is it intended to limit the scope of the present disclosure. Other features of the present disclosure will become readily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Some example embodiments will now be described with reference to the accompanying drawings, in which:

[0014] Figure 1 An example communication environment is shown in which example embodiments of the present disclosure may be implemented;

[0015] Figure 2 A signaling diagram illustrating an example routing process of a NAS message according to some example embodiments of the present disclosure;

[0016] Figure 3 A schematic diagram showing an example NAS message transmission configuration according to some example embodiments of the present disclosure;

[0017] Figure 4 A signaling diagram illustrating an example routing process of a NAS message according to some example embodiments of the present disclosure;

[0018] Figure 5 A schematic diagram showing an example NAS message transmission configuration according to some example embodiments of the present disclosure;

[0019] Figure 6 A signaling diagram illustrating an example routing process of a NAS message according to some example embodiments of the present disclosure;

[0020] Figure 7 A schematic diagram showing an example NAS message transmission configuration according to some example embodiments of the present disclosure;

[0021] Fig. 8A A signaling diagram illustrating an example routing process of a NAS message according to some example embodiments of the present disclosure;

[0022] Figure 8B A signaling diagram illustrating an example routing process of a NAS message according to some example embodiments of the present disclosure;

[0023] Fig.9A A schematic diagram showing an example NAS message transmission configuration according to some example embodiments of the present disclosure;

[0024] Fig. 9B A schematic diagram showing an example NAS message transmission configuration according to some example embodiments of the present disclosure;

[0025] Fig.10A schematic diagram illustrating an example NAS Data Adaptation Protocol (NDAP) PDU according to some example embodiments of the present disclosure;

[0026] Fig.11A A schematic diagram showing an example NDAP PDU header structure according to some example embodiments of the present disclosure;

[0027] Fig. 11B A schematic diagram showing an example NDAP PDU header structure according to some example embodiments of the present disclosure;

[0028] Fig. 11C A schematic diagram showing an example NDAP PDU header structure according to some example embodiments of the present invention;

[0029] Fig.12 A schematic diagram showing an example NAS service flow according to some example embodiments of the present disclosure;

[0030] Fig.13 A flowchart showing a method implemented at a first device according to some example embodiments of the present disclosure;

[0031] Fig.14 A flowchart showing a method implemented at a second device according to some example embodiments of the present disclosure is shown;

[0032] Fig.15 shows a simplified block diagram of a device suitable for implementing an example embodiment of the present disclosure; and

[0033] Fig.16 A block diagram illustrating an example computer-readable medium according to some example embodiments of the present disclosure.

[0034] Throughout the drawings, the same or similar reference numerals refer to the same or similar elements. DETAILED DESCRIPTION

[0035] The principles of the present disclosure will now be described with reference to some example embodiments. It should be understood that these embodiments are described only for the purpose of illustration and to help those skilled in the art understand and implement the present disclosure without implying any limitation on the scope of the present disclosure. In addition to the methods described below, the embodiments described herein can be implemented in various ways.

[0036] In the following description and claims, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.

[0037] In this disclosure, references to "one embodiment," "an embodiment," "an example embodiment," etc. indicate that the described embodiment may include a particular feature, structure, or characteristic, but not every embodiment necessarily includes the particular feature, structure, or characteristic. Moreover, such phrases do not necessarily refer to the same embodiment. Further, when a particular feature, structure, or characteristic is described in conjunction with an embodiment, it is considered to be within the knowledge of those skilled in the art to affect such feature, structure, or characteristic in conjunction with other embodiments, whether or not explicitly described.

[0038] It should be understood that, although the terms "first", "second" etc. in front of nouns etc. can be used to describe various elements in this article, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element, and they do not limit the order of nouns. For example, without departing from the scope of the exemplary embodiment, the first element can be referred to as the second element, and similarly, the second element can be referred to as the first element. As used herein, the term "and / or" includes any and all combinations of one or more listed terms.

[0039] As used herein, “at least one of: ” and “at least one of ” and similar expressions (wherein a list of two or more elements is connected by “and” or “or”) refer to at least any one of the elements, or at least any two or more of the elements, or at least all of the elements.

[0040] As used herein, unless explicitly stated, performing a step “in response to A” does not mean performing the step immediately after “A” occurs, but may include one or more intermediate steps.

[0041] The terms used herein are used only for the purpose of describing specific embodiments and are not intended to limit the example embodiments. As used herein, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that when used herein, the terms "comprises", "comprising", "has", "having", "includes", and / or "including" specify the presence of features, elements, and / or parts, etc., but do not exclude the presence or addition of one or more other features, elements, parts, and / or combinations thereof.

[0042] As used in this application, the term "circuitry" may refer to one or more or all of the following:

[0043] a) hardware circuit implementation only (e.g., implementation only in analog and / or digital circuits), and

[0044] b) a combination of hardware circuitry and software such as (if applicable):

[0045] (i) a combination of analog and / or digital hardware circuitry and software / firmware, and

[0046] (ii) any portion of a hardware processor (including a digital signal processor) with software, software and memory that work together to enable a device such as a mobile phone or server to perform various functions; and

[0047] c) A hardware circuit and / or processor that requires software (eg, firmware) for operation, such as a microprocessor or portion of a microprocessor, but the software may not be present when not needed for operation.

[0048] This definition of circuitry applies to all uses of this term in this application, including in any claims. As a further example, as used in this application, the term circuitry also covers an implementation of only a hardware circuit or processor (or multiple processors) or a portion of a hardware circuit or processor and its (or their) accompanying software and / or firmware. The term circuitry also covers, for example and if applicable to a particular claim element, a baseband integrated circuit or processor integrated circuit for a mobile device or a similar integrated circuit in a server, cellular network device, or other computing or network device.

[0049] As used herein, the term "communication network" refers to a network that complies with any suitable communication standard, for example, New Radio (NR), Long Term Evolution (LTE), Advanced LTE (LTE-A), Wideband Code Division Multiple Access (WCDMA), High Speed ​​Packet Access (HSPA), Narrowband Internet of Things (NB-IoT), etc. In addition, the communication between the terminal device and the network device in the communication network can be performed according to any suitable generation communication protocol, including but not limited to the first generation (1G), second generation (2G), 2.5G, 2.75G, third generation (3G), fourth generation (4G), 4.5G, fifth generation (5G), sixth generation (6G) communication protocol and / or any other protocol currently known or developed in the future. The embodiments of the present disclosure can be applied to various communication systems. In view of the rapid development of communication, there are of course future types of communication technologies and systems that can implement the present disclosure. It should not be considered that the scope of the present disclosure is limited to the above-mentioned system.

[0050] As used herein, the term "network device" refers to a node in a communication network via which a terminal device accesses the network and receives services from it. A network device may refer to a base station (BS) or an access point (AP), such as a Node B (NodeB or NB), an evolved Node B (eNodeB or eNB), a NR NB (also referred to as a gNB), a remote radio unit (RRU), a radio head (RH), a remote radio head (RRH), a repeater, an integrated access and backhaul (IAB) node, a low-power node such as a femto, a micro), a non-terrestrial network (NTN) or a non-terrestrial network device (such as a satellite network device, a low earth orbit (LEO) satellite and a geosynchronous orbit (GEO) satellite, an aircraft network device, etc.), depending on the terminology and technology applied. In some example embodiments, a radio access network (RAN) split architecture includes a centralized unit (CU) and a distributed unit (DU) at an IAB donor node. An IAB node includes a mobile terminal (IAB-MT) portion that behaves like a UE toward a parent node, and a DU portion of an IAB node behaves like a base station toward a next-hop IAB node.

[0051] The term "terminal device" refers to any terminal device capable of wireless communication. As an example and not limitation, the terminal device may also be referred to as a communication device, a user equipment (UE), a subscriber station (SS), a portable subscriber station, a mobile station (MS) or an access terminal (AT). The terminal device may include, but is not limited to, a mobile phone, a cellular phone, a smart phone, a voice over IP (VoIP) phone, a wireless local loop phone, a tablet computer, a wearable terminal device, a personal digital assistant (PDA), a portable computer, a desktop computer, an image capture terminal device such as a digital camera, a game terminal device, a music storage and playback facility, a vehicle-mounted wireless terminal device, a wireless endpoint, a mobile station, a laptop embedded device (LEE), a laptop mounted device (LME), a USB dongle, a smart device, a wireless user equipment (CPE), an Internet of Things (IoT) device, a watch or other wearable device, a head mounted display (HMD), a vehicle, a drone, medical equipment and applications (e.g., remote surgery), industrial equipment and applications (e.g., robots and / or other wireless devices operating in industrial and / or automatic processing chain environments), consumer electronic devices, equipment operating on commercial and / or industrial wireless networks, etc. The terminal device may also correspond to the mobile terminal (MT) part of an IAB node (eg, a relay node).In the following description, the terms "terminal device", "communication device", "terminal", "user equipment" and "UE" may be used interchangeably.

[0052] As used herein, the terms "resource", "transmission resource", "resource block", "physical resource block" (PRB), "uplink resource" or "downlink resource" may refer to any resource used to perform communication (e.g., communication between a terminal device and a network device), such as a resource in the time domain, a resource in the frequency domain, a resource in the spatial domain, a resource in the code domain, or any other combination of time domain, frequency domain, spatial domain and / or code domain resources to achieve communication. In the following, unless explicitly stated, resources in the frequency domain and the time domain will be used as examples of transmission resources for describing some example embodiments of the present disclosure. It should be noted that the example embodiments of the present disclosure are also applicable to other resources in other domains.

[0053] As used herein, the term "network function (NF)" may refer to individual components or services for the control plane (C-plane) or user plane (U-plane) in a core network (CN). Each network function may be considered as an independent and autonomous logical network element. Therefore, the addition, update, extension and / or removal of a network function will not affect other network functions in the CN. Network functions may communicate with each other via their respective interfaces.

[0054] The 5G network supports the following SRBs:

[0055] • SRB0 is used for the transmission of RRC messages using the Common Control Channel (CCCH).

[0056] SRB1 uses a dedicated control channel (DCCH) for RRC messages, which may include piggybacked NAS messages, and may also be used for NAS prior to the establishment of SRB2.

[0057] information.

[0058] • SRB2 is used for NAS and RRC messages including logged measurement information by using DCCH. SRB2 may have a lower priority than SRB1 and may be configured by the network after AS security activation.

[0059] SRB3 is used for specific RRC messages when the UE is in E-UTRAN New Radio Dual Connectivity (EN-DC), (NG)EN-DC, New Radio E-UTRA Dual Connectivity (NE-DC) or NR-DC by using DCCH.

[0060] • SRB4 uses DCCH for RRC messages including application layer measurement report information.

[0061] SRB4 may have a lower priority than SRB1 and can only be configured by the network after AS security activation.

[0062] As mentioned above, it is expected to implement distributed NAS terminals or multiple NAS terminals in the 6G network framework. As an example arrangement, the radio access network (RAN) can forward NAS messages between multiple UEs and NAS entities. This direct routing relies on decoding the NAS payload in the existing network framework. However, this method not only blurs the RAN / core domain boundary, but also exposes the NAS protocol to the RAN and may cause additional processing overhead.

[0063] The present disclosure provides a solution for efficiently routing NAS messages to appropriate network functions in the CN. In the solution, a RAN device provides a NAS message transmission configuration to a UE. The NAS message transmission configuration may indicate a mapping between a NAS service and a radio bearer and / or a mapping between a NAS service and a NAS service type identifier. Based on the NAS message transmission configuration, the RAN device may route NAS messages between the UE and a corresponding NF or a corresponding NAS entity. The corresponding NF or the corresponding NAS entity may be determined based on the NAS message transmission configuration.

[0064] Hereinafter, exemplary embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

[0065] Figure 1 An example communication environment 100 is shown in which example embodiments of the present disclosure may be implemented. The communication environment 100 may support distributed NAS terminals. In some cases, the communication environment 100 may deploy a service-based architecture.

[0066] The communication environment 100 may involve both the RAN and CN domains as well as the RAN-CN interface. Figure 1 As shown, the communication environment 100 includes a first device 110, a second device 120, and a plurality of third devices 130-1 to 130-N that can communicate with each other.

[0067] The first device 110 may be a network device in the RAN, such as a gNB. In some example embodiments, the first device 110 may be implemented as discrete components logically or physically. Figure 1 In the example shown, the first device 110 may also include a centralized unit (CU) 110-1 and a distributed unit (DU) 110-2. CU 110-1 may be divided into a CU-CP and a CU-UP. In particular, the CU-CP may be connected to DU 110-2 via an F1-C interface, and the CU-UP may be connected to DU 110-2 via an F1-U interface. It should be understood that a single DU is shown for illustrative purposes, and in some other embodiments, the first device 110 may include more than one DU. Therefore, the present disclosure is not limited in this regard.

[0068] The first device 110 may provide radio coverage for the second device 120. The second device 120 may be a terminal device, such as a UE. A plurality of third devices 130-1 to 130-N (hereinafter collectively referred to as third devices 130) may be a plurality of network functions in a CN and / or NAS entity.

[0069] In some example embodiments, the second device 120 may require multiple NAS services associated with multiple third devices 130-1 to 130-N, such as positioning, etc. Therefore, the corresponding NAS signaling connection is set to route NAS messages for these NAS services from the second device 120 to the corresponding third devices 130-1 to 130-N via the first device 110. In order to implement NAS routing between the second device 120 and the appropriate third device 130, the first device 110 may provide a NAS message transmission configuration to the second device 120, which will be discussed in detail later. In an embodiment, the transmission configuration may be pre-configured in the first device 110 and the second device 120.

[0070] In some example embodiments, a link from first device 110 to second device 120 is referred to as a downlink (DL), and a link from second device 120 to first device 110 is referred to as an uplink (UL). In DL, first device 110 is a transmission (TX) device (or transmitter), and second device 120 is a reception (RX) device (or receiver). In UL, second device 120 is a TX device (or transmitter), and first device 110 is an RX device (or receiver).

[0071] In some example embodiments, the operations described in conjunction with a terminal device may be implemented at a network device or other device, and the operations described in conjunction with a network device may be implemented at a terminal device or other device.

[0072] It should be understood that Figure 1 The number of devices and their connections shown in the figure are for illustrative purposes only and do not imply any limitation. The communication network 100 may include any suitable number of devices configured to implement the example embodiments of the present disclosure. Although not shown, it should be understood that one or more additional devices and connections may be deployed in the communication network 100.

[0073] The communication in the communication environment 100 may be implemented according to any suitable communication protocol, including but not limited to cellular communication protocols of the first generation (1G), second generation (2G), third generation (3G), fourth generation (4G), fifth generation (5G), sixth generation (6G), etc., wireless local area network communication protocols such as Institute of Electrical and Electronics Engineers (IEEE) 802.11, etc., and / or any other protocol currently known or developed in the future. In addition, the communication may use any suitable wireless communication technology, including but not limited to: code division multiple access (CDMA), frequency division multiple access (FDMA), time division multiple access (TDMA), frequency division duplex (FDD), time division duplex (TDD), multiple input multiple output (MIMO), orthogonal frequency division multiple access (OFDM), discrete Fourier transform spread OFDM (DFT-s-OFDM), and / or any other technology currently known or developed in the future.

[0074] Reference now Figure 2 , which shows a signaling diagram of an example routing process 200 according to some example embodiments of the present disclosure. Figure 2 As shown, the routing process 200 involves at least the first device 110, the second device 120, and the third device 130. For the purpose of discussion, reference is also made to Figure 1 The routing process 200 is described.

[0075] In the routing process 200 , the first device 110 provides ( 205 ) a NAS message transmission configuration to the second device 120 .

[0076] Then, the first device 110 routes the NAS message between the second device 120 and the third device 130 based at least on the NAS message transmission configuration.

[0077] like Figure 2 As shown, the second device 120 sends (210) a NAS message to the first device 110. For example, upon receiving the NAS message from the second device 120, the second device 120 may determine the destination (appropriate third device 130) to which the NAS message will be routed based on the NAS message transmission configuration and the information about the NAS message. Then, the first device 110 forwards (215) the NAS message to the appropriate third device 130 based on the NAS message transmission configuration. For a DL NAS message (i.e., sent from the third device 130), the first device may perform similar operations.

[0078] In the following, we will combine Figures 3 to 13 Describes various implementations of NAS message transmission configuration.

[0079] In some example embodiments, dedicated SRBs may be defined per NAS service. In addition, associated configurations related to the air interface protocol stack (e.g., PHY, MAC, RLC, PDCP, etc.) may be required. That is, dedicated SRBs may be introduced for NAS-based communications between terminal devices and network functions.

[0080] In this case, the NAS message transmission configuration may indicate a mapping between a NAS service (or NAS service type) and a corresponding dedicated SRB. As an example, a logical channel ID may be used to identify a dedicated SRB. The first device 110 may allocate a logical channel ID for the corresponding dedicated SRB. In some cases, this may require increasing the maximum value of the logical channel ID range. Additionally, in some example embodiments, different priorities may be associated with the corresponding SRBs. For example, the corresponding SRBs may be associated with different priorities of the NAS messages to which their business / service types belong.

[0081] Existing SRBs may be used in conjunction with dedicated SRBs. For example, SRB1 and / or SRB2 may be used to exchange NAS messages until dedicated SRBs are configured.

[0082] The first device 110 may configure a dedicated SRB before or after access stratum (AS) security for a specific network function. In some example embodiments, after configuring SRB1, AS security, and SRB2, the first device 110 may configure a dedicated SRB on demand. In some other embodiments, after configuring SRB1 and AS security, the first device 110 may configure a dedicated SRB on demand. In addition to the on-demand setup of the dedicated SRB, the dedicated SRB may be released on demand.

[0083] In some example embodiments, dedicated SRBs may be configured as required for each UE. In particular, depending on the UE type and / or the NAS service required, only specific SRBs may be configured. Figure 3 In the example shown, SRB#c may correspond to a positioning service. If the second device 120 does not require a positioning service, SRB#c may not be configured.

[0084] Figure 3 A schematic diagram of an example NAS message transmission configuration 300 is shown according to some example embodiments of the present disclosure. Figure 3 In the example shown, the second device 120 requires three NAS services provided by the third devices 130-1 to 130-3, which may correspond to different SRBs carrying NAS messages.

[0085] To this end, the first device 110 may configure the second device 120 with a mapping between a NAS service and a corresponding dedicated SRB, for example, SRB#a corresponds to NAS service#a, SRB#b corresponds to NAS service#b, and SRB#c corresponds to NAS service#c. Based on the mapping, the first device 110 may send a NAS message for a specific NAS service via the corresponding dedicated SRB. For example, the first device 110 may send a NAS message for NAS service#a to the second device via SRB#a, send a NAS message for NAS service#b to the second device via SRB#b, and send a NAS message for NAS service#c to the second device via SRB#c.

[0086] After receiving the NAS message, the first device 110 can determine the NAS service corresponding to the NAS message based on the mapping and the SRB carrying the NAS message. This is because the first device 110 also knows the NAS transmission configuration. In this case, for example, NAS signaling connections #a to #c associated with NAS services #a to #c are established between the first device 110 and the third devices 130-1 to 130-3, respectively. Therefore, the first device 110 can then route each of the NAS messages to the appropriate third device 130 (e.g., an appropriate NF or NAS entity) associated with the corresponding determined NAS service.

[0087] In this way, the first device 110 can associate the dedicated SRBs #a to #c to the corresponding NAS signaling connections #a to #c for the indicated NAS services. It should be understood that the first device 110 can perform similar operations for DL ​​NAS message transmission.

[0088] Figure 4 A signaling diagram of an example routing process 400 of NAS messages according to some example embodiments of the present disclosure is shown. The routing process 400 may be based on a NAS message transmission configuration indicating a mapping between a NAS message type and a corresponding dedicated SRB. For discussion purposes, reference is also made to Figure 1 The routing process 400 is described.

[0089] To initiate process 400 , the third device 130 may send ( 405 ) a DL NAS transfer message to CU 110 - 1 in the first device 110 via the NGAP protocol.

[0090] CU 110-1 may determine (410) a mapping between SRBs and network functions for NAS message transmission over an RRC interface.For example, SRBs may be identified by corresponding SRB identifications (IDs).

[0091] In some example embodiments, the NAS message transmission configuration indicating the mapping between the NAS service and the corresponding SRB can be statically configured. In this case, all terminal devices served by the first device 110 can be configured with the same mapping between the corresponding SRB and the NAS signaling connection during the RRC setup process. As an example, a mapping table of SRB IDs to NFs associated with the NAS service can be used for such static NAS message transmission configuration.

[0092] Additionally or alternatively, in some example embodiments, the NAS message transmission configuration indicating the mapping between the NAS services and the corresponding SRBs may be configured on demand. For example, the second device 120 may send an indication that one or more NAS services will be required by the second device 120 in an RRC message during the RRC setup process or after the RRC setup has been completed (e.g., in RRC_CONNECTED mode). The first device 110 may configure the mapping between the NAS services and the corresponding dedicated SRBs based on the indication. In this way, dynamic NAS message transmission configuration is supported, and the RAN configures dedicated SRBs only for those NAS services that are required.

[0093] CU 110-1 may provide (415) information about mapping between NAS services and corresponding SRB IDs to DU 110-2. The information about the corresponding SRB IDs may be carried in a DL RRC message, for example, via the F1AP protocol.

[0094] Therefore, DU 110-2 in the first device 110 may forward (420) information about mapping between NAS services and corresponding SRB IDs to the second device 120. For example, the information about the corresponding SRB ID may be carried in an RRC message.

[0095] Then, the second device 120 may perform NAS message transmission with the third device 130 via the first device 110 based on the information related to the mapping between the NAS service and the corresponding SRB ID. Figure 4 In the example of , which illustrates a UL communication scenario, the second device 120 sends ( 425 ) a NAS message to the DU 110 - 2 via a dedicated SRB having an SRB ID corresponding to the NAS service.

[0096] Therefore, DU 110-2 forwards (430) the NAS message to CU 110-1. CU 110-1 may determine (435) the NAS service corresponding to the dedicated SRB. For example, by looking up a mapping table of SRB IDs to NFs associated with NAS services, CU 110-1 may determine the corresponding network function based on the SRB ID of the dedicated SBR.

[0097] After determining the network function and / or the associated NAS entity, CU 110-1 may transmit (440) a NAS message to the determined NF or NAS entity (ie, third device 130) via a corresponding NAS signaling connection.

[0098] In DL communication, the first device 110 may receive a DL NAS message associated with a NAS service from the third device 130. The first device 110 may determine a dedicated SRB corresponding to the NAS service. In the case of a static NAS message transmission configuration, this may be accomplished by, for example, looking up a mapping table of SRB IDs to NFs associated with the NAS service. After determining the dedicated SRB, the first device 110 may send a DL NAS message to the second device 120 via the determined dedicated SRB.

[0099] In some other embodiments, the first device 110 may configure the second device 120 with a mapping between a NAS message type identifier and a NAS service. The second device 120 may additionally send a NAS message including the NAS message type identifier. The first device 110 may then route the NAS message to an appropriate 6G NF or NAS entity associated with the NAS service corresponding to the NAS message type identifier over a dedicated NAS signaling connection.

[0100] Figure 5 A schematic diagram of an example NAS message transmission configuration 500 is shown according to some example embodiments of the present disclosure. Figure 5 In the example shown, the second device 120 requires three NAS services provided by the third devices 130-1 to 130-3, which may correspond to different NAS message type identifiers. The identifier may be included in the header of the NAS message, for example as an RRC header or as an NDAP header (explained later).

[0101] Additionally or alternatively, for RRC UL information transfer messages from the second device 120 in RRC connected mode, a setup ID / pointer for identifying a specific NF instance can be configured together with the NAS service type identifier so that the first device 110 can route the NAS message to the appropriate 6GNF.

[0102] To this end, the first device 110 may configure the mapping between the NAS service and the corresponding NAS message type identifier to the second device 120, for example, the NAS message type identifier #a corresponds to the NAS service #a, the NAS message type identifier #b corresponds to the NAS service #b, and the NAS message type identifier #c corresponds to the NAS service #c. The configuration may be carried in the NAS transmission configuration. Based on the mapping, the first device 110 may transmit a NAS message including the corresponding NAS message type identifier and the NAS payload to the second device 120. For example, the first device 110 may send a NAS message including the corresponding NAS message type identifier #a, #b, or #c accordingly.

[0103] After receiving the NAS message, the first device 110 can determine the NAS service corresponding to the NAS message based on the mapping and the NAS message type identifier. In this case, for example, NAS signaling connections #a to #c associated with NAS services #a to #c are respectively set between the first device 110 and the third devices 130-1 to 130-3. Therefore, the first device 110 then routes each of the NAS messages to the appropriate NF or NAS entity associated with the corresponding determined NAS service. In this way, the first device 110 can associate the NAS message type identifiers #a to #c to the corresponding NAS signaling connections #a to #c for the indicated NAS services.

[0104] Figure 6 A signaling diagram of an example routing process 600 of NAS messages according to some example embodiments of the present disclosure is shown. The routing process 600 may be based on a NAS message transmission configuration indicating a mapping between a NAS message type identifier and a corresponding NAS service. For discussion purposes, reference is also made to Figure 1 The routing process 600 is described.

[0105] In process 600 , a NAS message type identification may be introduced for each NAS-based communication (ie, NAS message transmission between the second device 120 and the corresponding third device 130 ).

[0106] The NAS message identity may be standardized (completely static), preconfigured in the second device 120 and the first device 110, or dynamically negotiated when the first NAS connection is established. If it is dynamically determined, this may be provided to the first device 110 via NGAP.

[0107] like Figure 6As shown, the second device 110 may send (610) a NAS message (e.g., an RRC UL information transfer message) to the DU 110-2 in the first device 110. The NAS message may include a NAS message type identifier and a NAS payload. The DU 110-2 may forward (615) the NAS message including the NAS message type identifier and the NAS payload to the CU 110-1 in the first device 110.

[0108] Based on the NAS message type identifier, CU 110-1 may determine (620) a NAS service corresponding to the NAS message type identifier. For example, CU 110-1 may determine the corresponding network function based on the NAS message type identifier by looking up a mapping table of NAS message type identifiers to NAS services.

[0109] After determining the network function and / or the associated NAS entity, CU 110 - 1 may transmit ( 625 ) a NAS message to the determined NAS entity (ie, third device 130 ) via a corresponding NAS signaling connection.

[0110] In some further embodiments, the first device 110 may configure the second device 120 with a mapping between a NAS service and a corresponding dedicated DRB.

[0111] Furthermore, the mapping between the corresponding dedicated DRB and the F1-U tunnel may be used to transmit NAS messages to the destination NF.

[0112] Figure 7 FIG. 7 is a schematic diagram showing an example NAS message transmission configuration 700 according to some example embodiments of the present disclosure. Figure 7 In the example shown, the second device 120 requires three NAS services provided by the third devices 130-1 to 130-3, which may correspond to different SRBs carrying NAS messages.

[0113] As shown, the first device 110 may configure the mapping between the NAS service and the corresponding dedicated DRB to the second device 120, for example, DRB#a corresponds to NAS service#a, DRB#b corresponds to NAS service#b, and DRB#c corresponds to NAS service#c. Based on the mapping, the first device 110 may send a NAS message for a specific NAS service via the corresponding dedicated DRB. For example, the first device 110 may send a NAS message for NAS service#a to DU 110-2 in the first device 110 via DRB#a, send a NAS message for NAS service#b to DU 110-2 in the first device 110 via DRB#b, and send a NAS message for NAS service#c to DU 110-2 in the first device 110 via DRB#c.

[0114] After receiving the NAS messages, the DU 110 - 2 may forward each of the NAS messages to the CU 110 - 1 in the first device 110 via the corresponding F1-U tunnel by using the mapping between the corresponding dedicated DRB and the F1-U tunnel.

[0115] CU 110-1 can determine the NAS service corresponding to the F1-U tunnel based on the mapping. In this case, for example, NAS signaling connections #a to #c associated with NAS services #a to #c are established accordingly between the first device 110 and the third devices 130-1 to 130-3. Therefore, the first device 110 then routes each NAS message to the appropriate NF or NAS entity associated with the corresponding determined NAS service. In this way, the first device 110 can associate dedicated DRBs #a to #c to the corresponding NAS signaling connections #a to #c for the indicated NAS services. It should be understood that the first device 110 can perform similar operations for DL ​​NAS message transmission.

[0116] Fig. 8A and Figure 8B 800 and 802 are signaling diagrams illustrating example routing processes 800 and 802 of NAS messages according to some example embodiments of the present disclosure. The routing processes 800 and 802 may be based on a NAS message transmission configuration indicating a mapping between a NAS service and a corresponding dedicated DRB. For discussion purposes, reference is also made to Figure 1 800 and 802 are described below.

[0117] like Fig. 8A As shown, after the RRC connection establishment is completed, the first device 110 (e.g., CU 110-1) sends (805) an E1AP message (e.g., a bearer context establishment request) including an indication of the NAS service type to the third device 130. Then the mapping between the F1-U tunnel and the NAS service (i.e., the NAS signaling connection) can be established at the third device 130 (810). It should be understood that the mapping of the F1-U tunnel to the NAS service can be indicated by a table lookup, and the mapping can be established statically or dynamically.

[0118] The third device 130 then sends (815) a tunnel endpoint of the NF associated with the corresponding NAS service to CU 110-1 via, for example, a bearer context establishment response. CU 110-1 encodes (820) an RRC reconfiguration message and sends (825) an F1AP message indicating the NAS type and the corresponding RRC container to DU 110-2, such as a UE context modification request. Tunnel allocation can be performed between DU 110-2 and CU 110-1 (830).

[0119] DU 110-2 may then send (835) an RRC reconfiguration message to second device 120, indicating the configured mapping between the NAS service and the corresponding dedicated DRB. DU 110-2 may then send (840) an F1AP message, such as a UE context modification response, to CU 110-1 to indicate that the RRC reconfiguration has been completed. A dedicated F1-U tunnel establishment for NAS message transmission may then be completed between CU 110-1 and DU 110-2 (845).

[0120] like Figure 8B As shown, for DL ​​NAS message transmission, in response to receiving (850) a DL NAS message from the third device 130, based on the NAS service associated with the DL NAS message / NF and the mapping between the NAS service and the F1-U tunnel, the CU 110-1 can determine (855) the F1-U tunnel for routing the DL NAS message.

[0121] Then, CU 110 forwards (860) the DL NAS message to DU 110-2 via the determined F1-U tunnel. Using the mapping between the F1-U tunnel and the corresponding dedicated DRB, DU 110-2 can send (865) the DL NAS message to the second device 120 via the dedicated DRB corresponding to the determined F1-U tunnel.

[0122] For DL ​​NAS message transmission, the second device 120 may send (870) an UL NAS message to the DU 110-2 via a dedicated DRB. By using the mapping between the F1-U tunnel and the corresponding dedicated DRB, the DU 110-2 may determine the F1-U tunnel corresponding to the dedicated DRB and forward (875) the UL NAS message to the CU 110-1 via the determined F1-U tunnel.

[0123] Then, CU 110-1 may determine (880) the NAS service corresponding to the F1-U tunnel and send (885) an UL NAS message to a third device 130 that is associated with the NAS service or capable of providing the NAS service. In this manner, the RAN device may route NAS messages through a dedicated NAS signaling connection between the UE and the appropriate NAS entity.

[0124] In some other embodiments, a new layer in the radio protocol stack may be introduced for UE and RAN, which may be referred to as a new NAS data adaptation protocol (NDAP). NDAP may be introduced for NAS message routing / transport, which may allow NAS messages to be routed to / from a specific NAS terminal entity in the network.

[0125] In some embodiments, the NDAP layer may be used by a higher layer for RRC (assuming that NAS messages are still sent using RRC containers) or other layers (e.g., PDCP-U, PDCP-C). Fig.9A As shown, in the radio protocol stack 900, the introduced NDAP layer 902 may be a higher layer for the RRC layer 904. Fig. 9B As shown, the introduced NDAP layer 912 may be a higher layer for the PDCP layer 914 .

[0126] In some embodiments, the introduced NDAP layer may make the multi-point connectivity between the RAN and the CN transparent to the RRC or other layers (eg, PDCP-U, PDCP-C) used for NAS messaging.

[0127] Furthermore, for the introduced NDAP layer, a new NDAP Protocol Data Unit (PDU) is introduced correspondingly, which may include an NDAP PDU header encrypted / integrity protected only at the RAN level.

[0128] In this case, a mapping between a NAS entity (e.g., which may be equal to / correspond to a corresponding NAS service) and a NAS service flow (NSF) (e.g., which may be equal to / correspond to a NAS service type) may be configured. For example, an NSF ID (e.g., which may be equal to / correspond to a NAS service type identifier) ​​is an integer value that allows a NAS entity at a CN to be identified in a unique manner. The range of NSF IDs may be standardized and cannot be changed. The range may affect the length of the NDAP PDU header.

[0129] like Fig.10 As shown, in NDAP PDU 1000, NDAP header 1010 can be presented as 1 eight-bit byte. NDAP PDU 1000 can also include data 1020, i.e., NAS message payload. However, as described above, the length of the NDAP PDU header can depend on the range of NSF IDs. The NDAP PDU header is expected to contain at least the NSF ID. However, it can also contain other elements (e.g., to allow instant changes in mapping).

[0130] In some embodiments, the NDAP PDU header may be mandatory for each NAS PDU (NDAP SDU). However, it may be allowed to skip the NDAP PDU header as long as unique identification of the NAS entity is not required. The NDAP PDU header may be truncated by the RAN before sending the NAS PDU to the CN. Once the NAS PDU is received from the CN, the NDAP PDU header may be added by the RAN core. An example of the structure 1100 with only a 6-bit NSF ID is shown in FIG. Fig.11A As shown, there are two "R" bits 1102 and 1104 and the NSF ID 1106 occupies 6 bits.

[0131] In some embodiments, a default NSF associated with a default NAS entity may be defined. Whenever a specific association is not defined, it is recommended to use such an association. As an example, NSF ID=0 may be used for the default NSF. However, it may also be set to other values. One condition that needs to be met is to make the default NSF ID known to all relevant parties (i.e., UE, RAN, and CN).

[0132] In the initial stage, the mapping between NAS entities and NSF IDs (e.g., which can also be considered as NAS services and NAS service type IDs) can be configured by 6G at the RAN level. The mapping can be established no earlier than the NAS security context is established. This means that in this solution, the default mapping between NAS messages and NSFs in the initial stage (e.g., initial connection) can be used. That is, as long as the mapping is not established (e.g., with NSF ID=0), the default NSF can be used. At this stage, all UL NAS PDUs (messages) will be sent to the default NAS entity of the CN. Additionally, the 6G RAN can expect that all DL NAS PDUs (messages) will be sent by the default NAS entity in the initial stage.

[0133] In some embodiments, the security of NDAP PDU can be ensured by using 6G RAN security context (NDAP PDU header encryption / decryption + integrity protection implemented at 6G RAN PDCP layer). This means that the NDAP PDU header is not encrypted at the NDAP level.

[0134] As mentioned above, on-the-fly mapping modifications are allowed. Modifications can be done via NAS. Modifications can be done only on NAS. Modifications are triggered only by CN. Whenever CN wants to modify the mapping, the solution suggests defining the DL NDAP PDU header in such a way that it allows to distinguish between NDAP PDUs containing regular NAS messages (not related to mapping changes) and NAS messages related to mapping changes. An example of a 6-bit NSF ID and a 1-byte NDAP PDU header structure 1110 can be found at Fig. 11B As shown, NSFID 1116 occupies 6 bits, with the first bit ("D / C" field 1112) allowing for differentiation.

[0135] In addition, in order to confirm the mapping change on the UE side, the UL NDAP PDU header can be modified so that the UE can use the next NAS PDU to announce the use of the new mapping. For example, the 6-bit NSF ID and 1-byte NDAP PDU header structure 1120 can be modified in the UE side. Fig. 11C As shown, the NSF ID 1126 occupies 6 bits, with the first bit ("L" field 1112) allowing for an indication that this is the last NAS PDU using the old mapping.

[0136] Based on this solution, there are two types of NAS messaging, namely RRC-based NAS messaging and RRC-independent NAS messaging. For RRC-based NAS messaging, the NDAP PDU is sent inside the RRC container (in a NAS dedicated message or piggyback). This means that in this variant of the solution, Fig.9A As shown, the NDAP layer 902 directly cooperates with the RRC 904. The DL NDAP PDU is propagated to the RRC for transmission. The UL NDAP PDU is propagated to the NDAP entity.

[0137] For NAS messaging independent of RRC, the NDAP layer for NAS messaging handled outside of RRC can be used. When NAS PDUs are sent without using RRC containers. This means that they are sent using dedicated RBs. In this case, it is recommended that the NDAP layer, in addition to what has been described above, also manages the mapping between NSFs and RBs. This means that, for example, Fig. 9B As shown, the NDAP layer 912 cooperates directly with the PDCP layer 914. The NDAP entity is associated with the PDCP entity, and thus DL NDAP PDUs are propagated to the correct PDCP entity for transmission. UL NDAP PDUs are propagated to the NDAP entity.

[0138] Additionally, for NAS signaling based on the C-plane (PDCP-S), a dedicated SRB is used for NAS message delivery. For NAS signaling based on the U-plane (PDCP-U), a dedicated DRB is used for NAS message delivery. That is, the scheme of NAS message transmission by introducing the new NDAP can also be combined with other schemes of NAS message transmission mentioned above, for example, by configuring the mapping between NAS services and corresponding dedicated SRBs and / or DRBs.

[0139] Fig.12 FIG. 1 is a schematic diagram of an example NAS message transmission configuration 1200 according to some example embodiments of the present disclosure. Fig.12 In the example shown, a mapping between NAS entities and NSF IDs can be established. Based on the new NDAP layer and mapping, NAS messages associated with NSF IDs #a, #b, and #c can be transmitted between the second device 120 and the corresponding NAS entities (third devices 130-1 to 130-3) corresponding to NSF IDs #a, #b, and #c.

[0140] Furthermore, depending on RAN support, it is possible that one of the options is used for all NAS services required by the UE. For example, SRBx+NAS signaling connection for NAS-MM services and SRBy+NAS signaling connection for positioning services.

[0141] It is also possible that different options may be used together. For example, in one option, the RAN may configure the UE as follows, for example, SRBx+NAS signaling connection for NAS-MM services and DRBx+NAS signaling connection for positioning services.

[0142] Based on the solution of the present disclosure, a communication framework including distributed (or multiple) NAS terminals can be implemented. In this way, direct routing of NAS messages to appropriate 6G NFs is enabled.

[0143] Fig.13 A flowchart of an example method 1300 implemented at a first device according to some example embodiments of the present disclosure is shown. For the purpose of discussion, Figure 1 The perspective description method 1300 of the first device 110 in the embodiment.

[0144] At block 1310 , the first device 110 provides a NAS message transmission configuration to the second device, the NAS message transmission configuration indicating at least one of a mapping between a NAS service and a radio bearer or a mapping between a NAS service and a NAS service type identifier.

[0145] At block 1320 , the first device 110 routes NAS messages between the second device and a third device based at least on the NAS message transmission configuration, wherein the third device is determined from among the plurality of devices based on the NAS message transmission configuration.

[0146] In some demonstrative embodiments, the mapping between the NAS service and the radio bearer comprises at least one of: a mapping between the NAS service and a corresponding dedicated signaling radio bearer (SRB), or a mapping between the NAS service and a corresponding dedicated data radio bearer (DRB).

[0147] In some example embodiments, different priorities are associated to corresponding radio bearers.

[0148] In some example embodiments, the method 1300 further comprises: receiving, from the second apparatus, an indication of one or more NAS services to be required by the second device; and configuring the at least one mapping based on the indication.

[0149] In some example embodiments, the method 1300 further comprises sending, to the second device, a request for the second device to report one or more NAS services to be required by the second device.

[0150] In some example embodiments, method 1300 further includes: in response to receiving a downlink NAS message associated with the NAS service from a third device, determining a dedicated SRB corresponding to the NAS service based on a NAS message transmission configuration; and sending the downlink NAS message to the second device via the determined dedicated SRB.

[0151] In some example embodiments, the method 1300 further includes: in response to receiving an uplink NAS message from the second device via the dedicated SRB, determining a NAS service corresponding to the dedicated SRB; and sending the uplink NAS message to a third device associated with the determined NAS service.

[0152] In some example embodiments, in a radio resource control (RRC) state, corresponding DRBs are mapped to corresponding F1-U tunnels, and wherein each of the corresponding F1-U tunnels is mapped to a NAS service.

[0153] In some example embodiments, method 1300 further includes: in response to receiving a downlink NAS message associated with the NAS service from a third device, determining an F1-U tunnel corresponding to the NAS service; and sending a downlink NAS message to the second device via a dedicated DRB corresponding to the determined F1-U tunnel.

[0154] In some example embodiments, method 1300 further includes: in response to receiving an uplink NAS message from a second device via a dedicated DRB, determining an F1-U tunnel corresponding to the dedicated SRB; and sending an uplink NAS message to a third device associated with a NAS service corresponding to the determined F1-U tunnel.

[0155] In some example embodiments, the method 1300 further includes: in response to receiving an uplink NAS message from the second device, detecting a NAS service type identifier of the NAS service from the uplink NAS message; and sending the uplink NAS message to the third device based on the NAS service type identifier.

[0156] In some example embodiments, the method 1300 further includes routing NAS messages between the second device and the third device based on a NAS Data Adaptation Protocol (NDAP).

[0157] In some example embodiments, a NAS data packet of a NAS message includes an NDAP header and a payload of the NAS message, wherein a NAS service type identifier corresponding to a NAS service of the NAS message is indicated in the NDAP header.

[0158] In some example embodiments, method 1300 further includes: in response to receiving a NAS data packet of a NAS message, determining a NAS service type identifier corresponding to the NAS service of the NAS message from an NDAP header of the NAS data packet; and routing the NAS message by a third device or a second device corresponding to the NAS service type identifier.

[0159] In some example embodiments, the first apparatus comprises a radio access network device, the second apparatus comprises a NAS entity of a terminal device, and the third apparatus comprises a NAS entity or a network function of a core network.

[0160] Fig.14 A flowchart of an example method 1400 implemented at a second device according to some example embodiments of the present disclosure is shown. For the purpose of discussion, Figure 1 The method 1400 is described from the perspective of the second device 120 in FIG.

[0161] In block 1410 , the second device 120 obtains a NAS message transmission configuration from the first device, the NAS message transmission configuration indicating a mapping between NAS services and radio bearers or a mapping between NAS services and NAS service type identifiers.

[0162] At block 1420 , the second device 120 performs NAS message transmission between the second device and the third device via the first device based at least on the NAS message transmission configuration.

[0163] In some example embodiments, the method 1400 further comprises sending, to the first apparatus, an indication of one or more NAS services to be required by the second apparatus, wherein the obtained NAS message transmission configuration is based on the sent indication.

[0164] In some example embodiments, the method 1400 further includes receiving, from the first device, a request for the second device to report one or more NAS services required by the second device.

[0165] In some example embodiments, the mapping between NAS services and radio bearers includes at least one of: a mapping between NAS services and corresponding dedicated signaling radio bearers (SRBs), or a mapping between NAS services and corresponding dedicated data radio bearers (DRBs).

[0166] In some example embodiments, the method 1400 further comprises sending the NAS message via one of: a dedicated SRB corresponding to the NAS service of the NAS message, or a dedicated DRB corresponding to the NAS service of the NAS message.

[0167] In some example embodiments, the method 1400 further includes sending the NAS message along with a NAS service type identifier corresponding to the NAS service of the NAS message.

[0168] In some example embodiments, the method 1400 further includes performing, via the first device, NAS message transmission between the second device and the third device based on a NAS Data Adaptation Protocol (NDAP).

[0169] In some example embodiments, a NAS data packet of a NAS message includes an NDAP header and a payload of the NAS message, wherein a NAS service type identifier corresponding to a NAS service of the NAS message is indicated in the NDAP header.

[0170] In some example embodiments, the first apparatus comprises a radio access network device, the second apparatus comprises a terminal device, and the third apparatus comprises a NAS entity or a network function of a core network.

[0171] In some example embodiments, a first device (eg, Figure 1 The first device 110 in the method 1300 may include a component for performing the corresponding operation of the method 1300). The component may be implemented in any suitable form. For example, the component may be implemented in a circuit system or a software module. The first device may be implemented as or included in Figure 1 In the first device 110.

[0172] In some example embodiments, a first device includes: a component for providing a NAS message transmission configuration to a second device, the NAS message transmission configuration indicating at least one of a mapping between a NAS service and a radio bearer or a mapping between a NAS service and a NAS service type identifier; and a component for routing NAS messages between the second device and a third device based at least on the NAS message transmission configuration, wherein the third device is determined from a plurality of devices based on the NAS message transmission configuration.

[0173] In some example embodiments, the mapping between NAS services and radio bearers includes at least one of: a component for mapping between NAS services and corresponding dedicated signaling radio bearers (SRBs), or a component for mapping between NAS services and corresponding dedicated data radio bearers (DRBs).

[0174] In some example embodiments, different priorities are associated to corresponding radio bearers.

[0175] In some example embodiments, the first apparatus further comprises: means for receiving, from the second apparatus, an indication of one or more NAS services to be required by the second apparatus; and means for configuring at least one mapping based on the indication.

[0176] In some example embodiments, the first apparatus further comprises means for sending a request to the second apparatus for the second apparatus to report one or more NAS services to be required by the second apparatus.

[0177] In some example embodiments, the first device further includes: a component for determining a dedicated SRB corresponding to the NAS service based on the NAS message transmission configuration in response to receiving a downlink NAS message associated with the NAS service from the third device; and a component for sending the downlink NAS message to the second device via the determined dedicated SRB.

[0178] In some example embodiments, the first device further includes: means for determining a NAS service corresponding to the dedicated SRB in response to receiving an uplink NAS message from the second device via the dedicated SRB; and means for sending the uplink NAS message to a third device associated with the determined NAS service.

[0179] In some example embodiments, in a radio resource control (RRC) state, corresponding DRBs are mapped to corresponding F1-U tunnels, and wherein each of the corresponding F1-U tunnels is mapped to a NAS service.

[0180] In some example embodiments, the first device further includes: a component for determining an F1-U tunnel corresponding to the NAS service in response to receiving a downlink NAS message associated with the NAS service from a third device; and a component for sending a downlink NAS message to the second device via a dedicated DRB corresponding to the determined F1-U tunnel.

[0181] In some example embodiments, the first device further includes: a component for determining an F1-U tunnel corresponding to a dedicated SRB in response to receiving an uplink NAS message from the second device via the dedicated DRB; and a component for sending an uplink NAS message to a third device associated with a NAS service corresponding to the determined F1-U tunnel.

[0182] In some example embodiments, the first device further includes: means for detecting a NAS service type identifier of the NAS service from the uplink NAS message in response to receiving the uplink NAS message from the second device; and means for sending the uplink NAS message to the third device based on the NAS service type identifier.

[0183] In some example embodiments, the first apparatus further comprises means for routing NAS messages between the second device and the third device based on a NAS Data Adaptation Protocol (NDAP).

[0184] In some example embodiments, a NAS data packet of a NAS message includes an NDAP header and a payload of the NAS message, wherein a NAS service type identifier corresponding to a NAS service of the NAS message is indicated in the NDAP header.

[0185] In some example embodiments, the first device further includes: a component for determining, in response to receiving a NAS data packet of the NAS message, a NAS service type identifier corresponding to the NAS service of the NAS message from an NDAP header of the NAS data packet; and a component for routing the NAS message to a third device or the second device corresponding to the NAS service type identifier.

[0186] In some example embodiments, the first apparatus comprises a radio access network device, the second apparatus comprises a NAS entity of a terminal device and the third apparatus comprises a NAS entity or a network function of a core network.

[0187] In some example embodiments, the first apparatus further comprises means for performing the method 1300 or other operations in some example embodiments of the first apparatus 110. In some example embodiments, the means comprises at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the performance of the first apparatus.

[0188] In some example embodiments, a second device (eg, Figure 1 The second device 120 in the method 1400 may include a component for performing the corresponding operation of the method 1400. The component may be implemented in any suitable form. For example, the component may be implemented in a circuit system or a software module. The second device may be implemented as or included in Figure 1 In the second device 120.

[0189] In some example embodiments, the second device includes: a component for acquiring a NAS message transmission configuration from the first device, the NAS message transmission configuration indicating a mapping between a NAS service and a radio bearer or a mapping between a NAS service and a NAS service type identifier; and a component for performing a NAS message transmission between the second device and the third device via the first device based at least on the NAS message transmission configuration.

[0190] In some example embodiments, the second apparatus further comprises means for sending, to the first apparatus, an indication of one or more NAS services required by the second apparatus, wherein the obtained NAS message transmission configuration is based on the transmitted indication.

[0191] In some example embodiments, the second apparatus further comprises means for receiving, from the first apparatus, a request for the second apparatus to report one or more NAS services to be required by the second apparatus.

[0192] In some example embodiments, the mapping between NAS services and radio bearers includes at least one of: a component for mapping between NAS services and corresponding dedicated signaling radio bearers (SRBs), or a component for mapping between NAS services and corresponding dedicated data radio bearers (DRBs).

[0193] In some example embodiments, the second apparatus further comprises means for sending the NAS message via one of: a dedicated SRB corresponding to the NAS service of the NAS message, or a dedicated DRB corresponding to the NAS service of the NAS message.

[0194] In some example embodiments, the second apparatus further comprises means for transmitting the NAS message together with a NAS service type identifier corresponding to the NAS service of the NAS message.

[0195] In some example embodiments, the second device further includes means for performing NAS message transmission between the second device and the third device via the first device based on a NAS Data Adaptation Protocol (NDAP).

[0196] In some example embodiments, a NAS data packet of a NAS message includes an NDAP header and a payload of the NAS message, wherein a NAS service type identifier corresponding to a NAS service of the NAS message is indicated in the NDAP header.

[0197] In some example embodiments, the first apparatus comprises a radio access network device, the second apparatus comprises a terminal device, and the third apparatus comprises a NAS entity or a network function of a core network.

[0198] In some example embodiments, the second apparatus further comprises means for performing the method 1400 or other operations in some example embodiments of the second apparatus 120. In some example embodiments, the means comprises at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the performance of the second apparatus.

[0199] Fig.15 1 is a simplified block diagram of a device 1500 suitable for implementing an exemplary embodiment of the present disclosure. The device 1500 may be provided to implement a communication device, such as Figure 1 The first device 110 or the second device 120 shown in FIG. As shown in the figure, the device 1500 includes one or more processors 1510, one or more memories 1520 coupled to the processor 1510, and one or more communication modules 1540 coupled to the processor 1510.

[0200] The communication module 1540 is used for two-way communication. The communication module 1540 has one or more communication interfaces to support communication with one or more other modules or devices. The communication interface may represent any interface necessary for communication with other network elements. In some example embodiments, the communication module 1540 may include at least one antenna.

[0201] Processor 1510 may be of any type suitable for the local technology network and may include, as non-limiting examples, one or more of: a general purpose computer, a special purpose computer, a microprocessor, a digital signal processor (DSP), and a processor based on a multi-core processor architecture. Device 1500 may have multiple processors, such as application specific integrated circuit chips that are time slaved to a clock of a synchronized main processor.

[0202] The memory 1520 may include one or more non-volatile memories and one or more volatile memories. Examples of non-volatile memories include, but are not limited to, read-only memory (ROM) 1524, electrically programmable read-only memory (EPROM), flash memory, hard disk, compact disk (CD), digital video disk (DVD), optical disk, laser disk, and other magnetic storage and / or optical storage. Examples of volatile memories include, but are not limited to, random access memory (RAM) 1522 and other volatile memories that will not persist until power is removed.

[0203] The computer program 1530 includes computer executable instructions executed by the associated processor 1510. The instructions of the program 1530 may include instructions for performing the operations / actions of some example embodiments of the present disclosure. The program 1530 may be stored in a memory, such as ROM 1524. The processor 1510 may perform any suitable actions and processes by loading the program 1530 into the RAM 1522.

[0204] The exemplary embodiments of the present disclosure may be implemented by the program 1530 so that the device 1500 may execute the Figures 2 to 14 Any process of the present disclosure discussed. The exemplary embodiments of the present disclosure may also be implemented by hardware or a combination of software and hardware.

[0205] In some example embodiments, program 1530 may be tangibly embodied in a computer-readable medium that may be included in device 1500 (e.g., in memory 1520) or in other storage devices accessible by device 1500. Device 1500 may load program 1530 from the computer-readable medium to RAM 1522 for execution. In some example embodiments, the computer-readable medium may include any type of non-transitory storage medium, such as ROM, EPROM, flash memory, hard disk, CD, DVD, etc. The term "non-transitory" as used herein is a limitation of the medium itself (i.e., tangible, not a signal), not a limitation on data storage persistence (e.g., RAM vs. ROM).

[0206] Fig.16 An example of a computer readable medium 1600 is shown, which may be in the form of a CD, DVD, or other optical storage disk. The computer readable medium 1600 has a program 1530 stored thereon.

[0207] Generally, various embodiments of the present disclosure may be implemented in hardware or dedicated circuits, software, logic, or any combination thereof. Some aspects may be implemented in hardware, and other aspects may be implemented in firmware or software executed by a controller, microprocessor, or other computing device. Although various aspects of the embodiments of the present disclosure are illustrated and described as block diagrams, flow charts, or using some other graphical representations, it should be understood that, as non-limiting examples, the blocks, devices, systems, techniques, or methods described herein may be implemented in hardware, software, firmware, dedicated circuits or logic, general hardware or controllers or other computing devices, or some combination thereof.

[0208] Some example embodiments of the present disclosure also provide at least one computer program product tangibly stored on a computer-readable medium (such as, non-volatile computer-readable medium). The computer program product includes computer executable instructions, such as those computer executable instructions executed in a device on a target physical or virtual processor included in a program module to perform any method as described above. Typically, a program module includes routines, programs, libraries, objects, classes, components, data structures, etc. that perform specific tasks or implement specific abstract data types. The functionality of the program modules can be combined or split between program modules as needed in various embodiments. The machine executable instructions for the program modules can be executed in local or distributed devices. In distributed devices, program modules can be located in local and remote storage media.

[0209] The program code for executing the method of the present disclosure may be written in any combination of one or more programming languages. The program code may be provided to a processor or controller of a general-purpose computer, a special-purpose computer, or other programmable data processing device, so that when the program code is executed by the processor or controller, the implementation of the functions / operations specified in the flowchart and / or block diagram is realized. The program code may be executed entirely on the machine, partially on the machine, as an independent software package, partially on the machine and partially on a remote machine, or entirely on a remote machine or server.

[0210] In the context of the present disclosure, computer program codes or related data may be carried by any suitable carrier to enable a device, apparatus or processor to perform various processes and operations as described above. Examples of carriers include signals, computer readable media, etc.

[0211] The computer readable medium may be a computer readable signal medium or a computer readable storage medium. The computer readable medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices, or equipment, or any suitable combination thereof. A more specific example of a computer readable storage medium may include an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage component, a magnetic storage component, or any suitable combination thereof.

[0212] In addition, although the operations are depicted in a specific order, this should not be understood as requiring the specific order shown or in a sequential order to perform these operations, or to perform all described operations, to achieve the desired result. In some cases, multitasking and parallel processing can be advantageous. Similarly, although several specific implementation details are included in the above discussion, these should not be interpreted as limitations on the scope of the present disclosure, but should be interpreted as descriptions of features that may be specific to a specific embodiment. Unless explicitly stated, certain features described in the context of a separate embodiment may also be implemented in combination in a single embodiment. On the contrary, unless explicitly stated, the various features described in the context of a single embodiment may also be implemented in multiple embodiments individually or in any suitable sub-combination.

[0213] Although the present disclosure has been described in language specific to structural features and / or methodological actions, it should be understood that the present disclosure defined in the appended claims is not necessarily limited to the specific features or actions described above. Rather, the specific features and actions described above are disclosed as example forms of implementing the claims.

[0214] In one aspect of the present disclosure, a first device for communication is provided, comprising: at least one processor; and at least one memory storing instructions, which, when executed by the at least one processor, cause the first device to at least: provide a non-access stratum (NAS) message transmission configuration to a second device, the NAS message transmission configuration indicating at least one of the following: a mapping between a NAS service and a radio bearer, or a mapping between a NAS service and a NAS service type identifier; and route NAS messages between the second device and a third device based at least on the NAS message transmission configuration, wherein the third device is determined from a plurality of devices based on the NAS message transmission configuration.

[0215] In some embodiments, the mapping between the NAS service and the radio bearer comprises at least one of: a mapping between the NAS service and a corresponding dedicated signaling radio bearer SRB, or a mapping between the NAS service and a corresponding dedicated data radio bearer DRB.

[0216] In some embodiments, different priorities are associated to the respective radio bearers.

[0217] In some embodiments, the first apparatus is caused to: receive from the second apparatus an indication of one or more NAS services to be required by the second apparatus; and configure the at least one mapping based on the indication.

[0218] In some embodiments, the first device is caused to send a request to the second device for the second device to report the one or more NAS services to be required by the second device.

[0219] In some embodiments, the first device is caused to: in response to receiving a downlink NAS message associated with the NAS service from the third device, determine a dedicated SRB corresponding to the NAS service based on the NAS message transmission configuration; and send the downlink NAS message to the second device via the determined dedicated SRB.

[0220] In some embodiments, the first device is caused to: in response to receiving an uplink NAS message from the second device via a dedicated SRB, determine a NAS service corresponding to the dedicated SRB; and send the uplink NAS message to the third device associated with the determined NAS service.

[0221] In some embodiments, in a radio resource control RRC state, corresponding DRBs are mapped to corresponding F1-U tunnels, and wherein each of the corresponding F1-U tunnels is mapped to a NAS service.

[0222] In some embodiments, the first device is caused to: determine the F1-U tunnel corresponding to the NAS service in response to receiving a downlink NAS message associated with the NAS service from the third device; and send the downlink NAS message to the second device via a dedicated DRB corresponding to the determined F1-U tunnel.

[0223] In some embodiments, the first device is caused to: determine the F1-U tunnel corresponding to the dedicated SRB in response to receiving an uplink NAS message from the second device via the dedicated DRB; and send the uplink NAS message to the third device associated with the NAS service corresponding to the determined F1-U tunnel.

[0224] In some embodiments, the first device is caused to: in response to receiving an uplink NAS message from the second device, detect a NAS service type identifier of a NAS service from the uplink NAS message; and send the uplink NAS message to the third device based on the NAS service type identifier.

[0225] In some embodiments, the first device is caused to: route the NAS message between the second device and the third device based on the NAS Data Adaptation Protocol NDAP.

[0226] In some embodiments, the NAS packet of the NAS message includes an NDAP header and a payload of the NAS message, wherein a NAS service type identifier corresponding to the NAS service of the NAS message is indicated in the NDAP header.

[0227] In some embodiments, the first device is caused to: in response to receiving a NAS packet of the NAS message, determine the NAS service type identifier corresponding to the NAS service of the NAS message from an NDAP header of the NAS packet; and route the NAS message to the third device or the second device corresponding to the NAS service type identifier.

[0228] In some embodiments, the first device comprises a radio access network device, the second device comprises a NAS entity of a terminal device, and the third device comprises a NAS entity or a network function of a core network.

[0229] In one aspect of the present disclosure, a second device for communication is provided, comprising: at least one processor; and at least one memory storing instructions, which, when executed by the at least one processor, cause the second device to at least: acquire a non-access stratum (NAS) message transmission configuration from a first device, the NAS message transmission configuration indicating a mapping between a NAS service and a radio bearer or a mapping between a NAS service and a NAS service type identifier; and perform NAS message transmission between the second device and a third device via the first device based at least on the NAS message transmission configuration.

[0230] In some embodiments, the second apparatus is caused to send to the first apparatus an indication of one or more NAS services to be required by the second apparatus, wherein the obtained NAS message transmission configuration is based on the sent indication.

[0231] In some embodiments, the second device is caused to: receive from the first device a request for the second device to report one or more NAS services to be required by the second device.

[0232] In some embodiments, the mapping between the NAS service and the radio bearer comprises at least one of: a mapping between the NAS service and a corresponding dedicated signaling radio bearer SRB, or a mapping between the NAS service and a corresponding dedicated data radio bearer DRB.

[0233] In some embodiments, the second apparatus is caused to: send the NAS message via one of: a dedicated SRB corresponding to the NAS service of the NAS message, or a dedicated DRB corresponding to the NAS service of the NAS message.

[0234] In some embodiments, the second apparatus is caused to send the NAS message together with a NAS service type identifier corresponding to the NAS service of the NAS message.

[0235] In some embodiments, the second device is caused to: perform the NAS message transmission between the second device and the third device via the first device based on the NAS Data Adaptation Protocol NDAP.

[0236] In some embodiments, the NAS packet of the NAS message includes an NDAP header and a payload of the NAS message, wherein a NAS service type identifier corresponding to the NAS service of the NAS message is indicated in the NDAP header.

[0237] In some embodiments, the first apparatus comprises a radio access network device, the second apparatus comprises a terminal device, and the third apparatus comprises a NAS entity or a network function of a core network.

[0238] In one aspect of the present disclosure, a method for communication is provided, comprising: providing a non-access stratum (NAS) message transmission configuration from a first device to a second device, the NAS message transmission configuration indicating at least one of the following: a mapping between a NAS service and a radio bearer, or a mapping between a NAS service and a NAS service type identifier; and routing NAS messages between the second device and a third device based at least on the NAS message transmission configuration, wherein the third device is determined from a plurality of devices based on the NAS message transmission configuration.

[0239] In one aspect of the present disclosure, a method for communication is provided, comprising: acquiring, at a second device, a non-access stratum (NAS) message transmission configuration from a first device, the NAS message transmission configuration indicating a mapping between a NAS service and a radio bearer or a mapping between a NAS service and a NAS service type identifier; and performing NAS message transmission between the second device and a third device via the first device based at least on the NAS message transmission configuration.

[0240] In one aspect of the present disclosure, a first device for communication is provided, comprising: a component for providing a non-access stratum (NAS) message transmission configuration to a second device, the NAS message transmission configuration indicating at least one of the following: a mapping between a NAS service and a radio bearer, or a mapping between a NAS service and a NAS service type identifier; and a component for routing NAS messages between the second device and a third device based at least on the NAS message transmission configuration, wherein the third device is determined from a plurality of devices based on the NAS message transmission configuration.

[0241] In one aspect of the present disclosure, a second device for communication is provided, comprising: a component for acquiring a non-access stratum (NAS) transmission configuration from a first device, the NAS transmission configuration indicating a mapping between a NAS service and a radio bearer or a mapping between a NAS service and a NAS service type identifier; and a component for performing NAS message transmission between the second device and a third device via the first device based on at least the NAS message transmission configuration.

[0242] In one aspect of the present disclosure, a computer-readable medium is provided, comprising instructions stored thereon, wherein the instructions are used to cause an apparatus to at least execute the method according to the aforementioned aspect.

Claims

1. A first device for communication, comprising: at least one processor; as well as at least one memory storing instructions, which, when executed by the at least one processor, cause the first device to at least: providing a non-access stratum (NAS) message transmission configuration to the second device, the NAS message transmission configuration indicating at least one of: a mapping between NAS services and radio bearers, or a mapping between NAS services and NAS service type identifiers; as well as A NAS message is routed between the second device and a third device based at least on the NAS message transmission configuration, wherein the third device is determined from among a plurality of devices based on the NAS message transmission configuration.

2. The first apparatus according to claim 1, wherein the mapping between the NAS service and the radio bearer comprises at least one of the following: The mapping between the NAS service and the corresponding dedicated signalling radio bearer (SRB), or The mapping between the NAS services and the corresponding dedicated data radio bearers (DRBs). The first apparatus according to claim 2 , wherein different priorities are associated to the corresponding radio bearers.

4. The first device according to any one of claims 1 to 3, wherein the first device is configured to: receiving, from the second device, an indication of one or more NAS services to be required by the second device; and The at least one mapping is configured based on the indication.

5. The first device according to claim 4, wherein the first device is configured to: A request is sent to the second device for the second device to report the one or more NAS services to be required by the second device.

6. The first device according to claim 2 or 3, wherein the first device is configured to: In response to receiving a downlink NAS message associated with a NAS service from the third device, determining a dedicated SRB corresponding to the NAS service based on the NAS message transmission configuration; and The downlink NAS message is sent to the second device via the determined dedicated SRB.

7. The first device according to claim 2 or 3, wherein the first device is configured to: In response to receiving an uplink NAS message from the second device via a dedicated SRB, determining a NAS service corresponding to the dedicated SRB; and The uplink NAS message is sent to the third device associated with the determined NAS service.

8. The first device according to claim 2 or 3, wherein in a radio resource control (RRC) state, corresponding DRBs are mapped to corresponding F1-U tunnels, and wherein each of the corresponding F1-U tunnels is mapped to a NAS service.

9. The first device according to claim 8, wherein the first device is caused to: In response to receiving a downlink NAS message associated with a NAS service from the third device, determining an F1-U tunnel corresponding to the NAS service; The downlink NAS message is sent to the second device via a dedicated DRB corresponding to the determined F1-U tunnel.

10. The first device according to claim 8, wherein the first device is caused to: In response to receiving an uplink NAS message from the second device via a dedicated DRB, determining an F1-U tunnel corresponding to the dedicated SRB; and The uplink NAS message is sent to the third device associated with the NAS service corresponding to the determined F1-U tunnel.

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