Fast access layer security

Abstract

This application relates to Fast Access Layer (AS) security. Techniques for rapidly establishing AS security are provided, particularly in conjunction with UE redirection or handover. For example, such techniques may include a base station configured to perform an RRC setup procedure with the UE, and after successfully completing the RRC setup procedure, sending a security key request message to the core network. This security key request message includes indications that the base station intends to immediately release the UE, and / or not establish a PDU session for the UE, and / or that settings for the UE's radio bearers will be suspended. The base station may also be configured to receive a security key information message from the core network in response to the security key request message. This security key information message includes security key information indicating a security key used to establish AS security for the UE.

Description

Technical Field

[0001] This disclosure relates generally to mobile communication systems, and more specifically to techniques for establishing access layer security. Background Technology

[0002] Examples of mobile communication systems can include Universal Mobile Telecommunications System (UMTS) (e.g., UMTS Terrestrial Radio Access Network (UTRAN)), Long Term Evolution (LTE), such as (LTE Evolved UTRAN (e-UTRAN), LTE Advanced (LTE-A), MulteFire, LTE-A Pro), Fifth Generation (5G) or New Radio (NR) (e.g., 5G / NR radio access technology), Sixth Generation (6G) (e.g., 6G radio access technology), etc. At least 5G systems (but can also be 6G systems) refer to Next Generation (NG) radio systems and network architectures. 5G and 6G network technologies are based on New Radio (NR) technology, but 5G / 6G (or NG) networks can also be built on E-UTRAN radio. It is estimated that 5G / NR can provide bit rates of 10-20 Gbit / s or higher and can support at least Enhanced Mobile Broadband (eMBB) and Ultra Reliable Low Latency Communication (URLLC) and Massive Machine-Type Communication (mMTC) services. 5G / NR is expected to provide ultra-wideband and ultra-robust, low-latency connectivity and massive networks to support the Internet of Things (IoT). List of acronyms and abbreviations 3GPP: Third Generation Partnership Project 5G: Fifth Generation 6G: Sixth Generation ACK: Confirmation AMF: Access and Mobility Management Functions AS: Access Layer gNB: Next-Generation Node B IE: Information Elements MM: Mobility Management NAS: Non-Access Layer NF: Network Functions NG: Next Generation NGAP: Next Generation Application Protocol NR: New Radio MAC: Media Access Control PDU: Protocol Data Unit RAN: Radio Access Network RLC: Radio Link Control RRC: Radio Resource Control SRB: Signaling Radio Bearer UE: User Equipment Summary of the Invention

[0003] In view of this disclosure, various exemplary embodiments solve at least some of the problems described herein or otherwise recognized by those skilled in the art.

[0004] Various exemplary embodiments are listed in the claims.

[0005] Some of the various exemplary embodiments have been described with respect to certain aspects. These aspects are not intended to indicate key or essential features of the various exemplary embodiments, nor are they intended to limit their scope. In view of this disclosure, those skilled in the art will recognize other features, aspects, and elements.

[0006] According to the example, an apparatus, method, computer-readable medium, and computer program product are provided for performing a Radio Resource Control (RRC) setup procedure with a base station; and after the RRC setup procedure has been successfully completed, receiving an RRC message from the base station, the RRC message including security information and encrypted measurement configuration information, the security information being information required by the user equipment to decrypt the encrypted measurement configuration information indicating the measurement to be performed by the user equipment.

[0007] Based on various developments / modifications, any of the foregoing method-related and / or device-related example aspects may include one or more of the following features (e.g., corresponding functions, operations, processors / instructions, components, circuit systems): • RRC messages are RRC security mode command messages that include security information. These messages carry encrypted measurement configuration information. • Decrypt the encrypted measurement configuration information using security information; perform measurements based on the decrypted measurement configuration information; and send a response to the RRC message to the base station, which includes a measurement report indicating the results of the measurements performed by the user equipment. • This response is an RRC safety mode completion message that carries a measurement report. • RRC messages also include integrity protection information. • Verify the integrity of RRC messages using integrity protection information; and perform measurements only if the integrity of the RRC messages is successfully verified, based on the decrypted measurement configuration information.

[0008] According to the example, an apparatus, method, computer-readable medium, and computer program product are provided for performing an RRC setup procedure with a user equipment; and after the RRC setup procedure has been successfully completed, sending an RRC message to the user equipment, the RRC message including security information and encrypted measurement configuration information, the security information being the information required by the user equipment to decrypt the encrypted measurement configuration information indicating the measurement to be performed by the user equipment.

[0009] Based on various developments / modifications, any of the foregoing method-related and / or device-related example aspects may include one or more of the following features (e.g., corresponding functions, operations, processors / instructions, components, circuit systems): • RRC messages are RRC security mode command messages that include security information. These messages carry encrypted measurement configuration information. • Receive a response to the RRC message from the user equipment, which includes a measurement report indicating the results of the measurement performed by the user equipment. • The response is an RRC safety mode completion message that carries a measurement report.

[0010] As indicated above, any of the foregoing devices is adapted, configured, or operable to perform or implement a corresponding function or operation. Any of the foregoing devices may be constructed, embodied, or implemented in various ways. For example, the device may include at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the device to at least perform or implement a corresponding function or operation; the device may include one or more components for performing or implementing a corresponding function or operation; the device may include one or more circuit systems for performing or implementing a corresponding function or operation, etc.

[0011] According to the example aspect, a system is provided that includes at least two of the devices according to any of the foregoing device-related example aspects (and / or any developments / modifications thereof).

[0012] According to the example aspect, a computer-readable medium including program instructions is provided for causing an apparatus (e.g., an apparatus according to any of the above-described apparatus-related example aspects (and / or any developments / modifications thereof)) to perform at least one of the above-described method-related example aspects (and / or any developments / modifications thereof).

[0013] According to the example aspect, a computer program product including (computer executable) computer program code is provided, which, when executed (or run) on a computer or when the program is run on a computer (e.g., a computer of an apparatus according to any of the foregoing apparatus-related example aspects (and / or any developments / modifications thereof), is configured to cause the computer to perform a method according to at least any of the foregoing method-related example aspects (and / or any developments / modifications thereof).

[0014] Computer program products may include or be embodied in (tangible / non-transitory) computer-readable (storage) media, on which computer-executable computer program code is stored, and / or the program may be directly loadable into the internal memory of a computer or its processor.

[0015] The term “non-transient” as used in this article refers to a limitation on the medium itself (e.g., a tangible medium, not a signal), rather than a limitation on the persistence of data storage (e.g., RAM vs. ROM).

[0016] Other developments and / or modifications to the aforementioned examples are described below.

[0017] By way of example embodiments, multiple technologies can be provided for establishing (e.g., enabling or otherwise facilitating or enabling) rapid AS security. The present invention is intended to provide a brief overview of some aspects (and features thereof) of various exemplary embodiments according to this disclosure. Therefore, it should be understood that the above aspects (and features thereof) are merely examples and should not be construed as limiting the scope of the various exemplary embodiments or the disclosure in any way. Other features, aspects, effects, and / or objects of this disclosure will become apparent from the following detailed description, drawings, and claims. Attached Figure Description

[0018] In the following description, various exemplary embodiments will be illustrated with reference to the accompanying drawings, wherein:

[0019] Figure 1 A schematic diagram of an example (mobile / wireless) communication system or network is shown;

[0020] Figure 2 A schematic diagram of an example wireless device or entity is shown;

[0021] Figure 3 A schematic diagram of an example network node or entity is shown;

[0022] Figure 4 This is a message sequence diagram illustrating the traditional procedure for establishing a secure RRC connection for a UE;

[0023] Figure 5This is a message sequence diagram of a program for requesting security key information according to an embodiment of the present invention;

[0024] Figure 6 This is a message sequence diagram of a program for requesting security key information according to another embodiment of the present invention;

[0025] Figure 7 This is a message sequence diagram of a procedure for notifying the core network of successful AS security activation according to another embodiment of the present invention;

[0026] Figure 8 This is a message sequence diagram of a procedure for simultaneous RRC release and safe mode activation according to an embodiment of the present invention;

[0027] Figure 9 This is a message sequence diagram of a procedure for simultaneous RRC release and safe mode activation according to another embodiment of the present invention;

[0028] Figure 10 This is a message sequence diagram of the simultaneous security mode activation and measurement procedure according to another embodiment of the present invention;

[0029] Figure 11 This is a message sequence diagram of an exemplary procedure for AS security activation with redirected RRC release according to an embodiment of the present invention;

[0030] Figure 12 This is a message sequence diagram of another exemplary procedure for AS security activation with redirected RRC release according to an embodiment of the present invention;

[0031] Figure 13 This is a message sequence diagram of an exemplary procedure for switching AS security activation according to an embodiment of the present invention; and

[0032] Figures 14A to 14B A message sequence diagram of an exemplary procedure for exploratory switching of AS security activation according to an embodiment of the present invention is shown. Detailed Implementation

[0033] Various exemplary embodiments are described herein with reference to specific, non-limiting, and illustrative examples. Those skilled in the art will understand that these various exemplary embodiments are by no means limited to these non-limiting and illustrative examples, but can be applied more broadly.

[0034] References to "one embodiment," "embodiment," "example embodiment," "some example embodiments," "certain example embodiments," and "various example embodiments," etc., in the specification indicate that the cited embodiments may include (multiple) specific features, structures, or characteristics, but each cited embodiment or example embodiment does not necessarily include (multiple) specific features, structures, or characteristics. Furthermore, such phrases do not necessarily refer to the same embodiment or example embodiment. Moreover, when (multiple) specific features, structures, or characteristics are described in connection with an embodiment or example embodiment, it is understood that implementing such features, structures, and characteristics in conjunction with any other embodiment or example embodiment is within the knowledge of those skilled in the art, regardless of whether such combinations are explicitly described.

[0035] It should be noted that detailed descriptions sometimes refer to one or more specifications used as non-limiting and exemplary examples of certain architectures, network configurations, and system deployments. More specifically, detailed descriptions refer to 3GPP standards as non-limiting and exemplary examples. Therefore, the exemplary embodiments provided herein may specifically employ terminology directly related to them. Such terminology is used only in the context of non-limiting and exemplary examples and is not intended to limit the exemplary embodiments in any way. Rather, any other system configuration or deployment may be utilized while adhering to the content described herein and / or the exemplary embodiments applicable to it.

[0036] For example, various example embodiments are applicable to any (e.g., mobile / wireless) communication system, such as 5G / NR systems and next-generation systems after 5G. For example, various example embodiments are applicable to 3GPP standardized mobile / wireless communication systems after 3GPP Release 19. Furthermore, while 5G / NR is referenced, other types of access / systems / networks are also supported / covered, such as future 3GPP radio / 6G, but also include non-3GPP access to the 3GPP core (such as, for example, untrusted non-3GPP access to the 3GPP core using, for example, N3IWF; trusted non-3GPP access to the 3GPP core using, for example, TNGF; wired access to the 3GPP core using, for example, W-AGF), etc.

[0037] When referring to specific terms of any such example system, these references should be understood / interpreted as applicable more generally in the sense of corresponding, similar, or equivalent. More specifically, when referring to network functions, entities, or elements of 5G / NR or 3GPP systems, it should be understood / interpreted that any network function, entity, or element of any system is referred to or encompassed by having or exhibiting corresponding, similar, or equivalent characteristics, functions, purposes, etc. As an illustrative but not exhaustive example, the reference to a base station or a base station should refer to or include any network function, entity, or element of any communication network that has or exhibits characteristics, functions, purposes, etc., corresponding to, similar to, or equivalent to the referenced base station or base station. For example, a base station or base station can be any network function, entity, or element configured to control / provide, or capable of controlling / providing, access to a corresponding cell.

[0038] In the following description, various exemplary embodiments are described using multiple variations and / or alternatives. It should generally be noted that, depending on certain implementations or constraints, all described variations and / or alternatives may be provided individually or in any possible combination (e.g., combinations of individual features of these various variations and / or alternatives are also included).

[0039] As used herein, the terms “comprising” and “including” should be understood to mean that the exemplary embodiments are not limited to consisting only of the features already mentioned, but may also include features, structures, units, modules, etc. not specifically mentioned.

[0040] As used herein, “at least one of the following: ” and “at least one of ” and similar expressions (such as “one or more of…”) (where the list of two or more elements is connected by “and” or “or”) means at least any one of the elements, or at least any two or more of the elements, or at least all of these elements. As used herein, the expression “and / or” means at least any one of the elements, or at least any two or more of the elements, or at least all of these elements.

[0041] As used herein, unless explicitly stated to the contrary, “in response to A” does not indicate that the step / operation / function is performed immediately after “A” occurs, as one or more intermediate steps / operations / functions may be included between them. Similarly, “based on A” does not indicate that the step / operation / function is performed solely based on “A”, as the referenced step / operation / function may be based on one or more other conditions (such as “B”) in addition to “A”.

[0042] As used herein, according to various example embodiments, any send or receive operation may include actual transmission or delivery operations, such as sending or transmitting associated information, data, signals, or messages, but may additionally or alternatively include associated processing operations, such as preparing / generating / issuing associated information, data, signals, or messages before sending, and / or acquiring / disposing of / processing associated information, data, signals, or messages after receiving. For example, sending information or data at / by a node may include generating / issuing and / or sending / transmitting its or corresponding signals or messages at / by a node, and receiving signals or messages at / by a node may include acquiring / disposing of and / or processing its or corresponding information or data at / by a node. As used herein, a signal or message may refer to and / or encompass any type of corresponding information, data, signal, etc.

[0043] In the accompanying drawings, it should be noted that the lines / arrows connecting individual blocks or entities are generally intended to illustrate operational coupling between them, which can be physical and / or logical coupling, on the one hand independent of the implementation (e.g., wired or wireless), and on the other hand may include any number of intermediate functional blocks or entities not shown. In flowcharts or sequence diagrams, the illustrated sequence of functions, operations, or actions is generally non-limiting and illustrative, and any other sequence of corresponding functions, operations, or actions may be contemplated where feasible.

[0044] Various example embodiments relate to considerations in (e.g., mobile / wireless) communication systems or networks, such as 5G / NR systems and next-generation / future systems beyond 5G. For example, various example embodiments are applicable to 3GPP standardized mobile / wireless communication systems or networks after 3GPP Release 19. These considerations specifically relate to…

[0045] • Quickly establish AS security, particularly (but not exclusively) in conjunction with UE redirection or handover, and even more specifically, in conjunction with UE redirection and handover in RRC connection mode.

[0046] • The technology used to request security key information, specifically (but not exclusively), applies even when the core network has not triggered initial context setting for the UE, even after the initial UE message has been sent to the UE.

[0047] • A technology for simultaneous RRC release and safe mode activation, and

[0048] • Technologies used to combine safety modes and measurement procedures.

[0049] Before explaining the example embodiments in further detail, refer to Figures 1 to 3Briefly explain some general aspects of (mobile / wireless) communication systems or networks to help understand the technology on which the described example embodiments are based.

[0050] Figure 1 An example of a (mobile / wireless) communication system or network 100 that can be used for wireless communication is illustrated. The communication system or network 100 includes wireless devices or entities (such as UEs 110 (e.g., 110A-110C)) connected to one or more network nodes or entities 130 via an interconnection network 125, and network nodes or entities (such as radio access nodes 120 (e.g., 120A-120B) (e.g., eNB, gNB, etc.)). The communication system or network 100 can be used in any suitable deployment scenario. Each UE 110 within coverage area 115 can be able to communicate directly with a radio access node 120 via a wireless interface. In some example embodiments, UEs 110 can also be able to communicate with each other via device-to-device (D2D) communication.

[0051] As an example, UE 110A can communicate with radio access node 120A via a wireless interface. That is, UE 110A can send wireless signals to and / or receive wireless signals from radio access node 120A. The wireless signals may contain voice services, data services, control signals, and / or any other suitable information.

[0052] As used herein, the term "User Equipment" (UE) has the full breadth of its common meaning and can refer to any type of wireless device or entity that can communicate with a network node or entity in a cellular or mobile or wireless / mobile communication system and / or another UE. Examples of UEs are target devices, D2D UEs, machine-type UEs or UEs capable of machine-to-machine (M2M) communication, personal digital assistants, tablet computers, mobile terminals, smartphones, embedded devices (LEEs) in laptop computers, laptop computer-mounted devices (LMEs), USB dongles, ProSe UEs, vehicle-to-vehicle (V2V) UEs, V2X UEs, machine-type communication (MTC) UEs, eMTC UEs, FeMTC UEs, UE Cat 0, UE Cat M1, narrowband Internet of Things (NB-IoT) UEs, UE Cat NB1, etc. The following is about... Figure 2 A sample implementation of the UE is described in more detail.

[0053] In some example embodiments, the wireless signal coverage area 115 associated with radio access node 120 may be referred to as a cell. However, specifically with regard to the concept of fifth-generation (5G) / new radio (NR) mobile communications, a beam may be used instead of a cell, and therefore it is important to note that the concepts described herein apply equally to both cells and beams.

[0054] Regarding a beam-based mobile communication system, a radio access node 120 (base station) can transmit beamforming signals to a UE 110 in one or more transmit directions (transmit beam, Tx beam). The UE 110 can receive beamforming signals from the base station 120 in one or more receive directions (receive beam, Rx beam). The UE 110 can also transmit beamforming signals to the base station 120 in one or more directions, and the base station 120 can receive beamforming signals from the UE 110 in one or more directions. The base station 120 and the UE 110 can determine optimal receive and transmit directions for each base station / UE pair, for example, in a sense that these directions result in the highest link quality or satisfy other quality conditions in the most suitable manner.

[0055] Interconnection network 125 can refer to any interconnection system capable of transmitting audio, video, signals, data, messages, or any combination thereof. Interconnection network 125 may include all or some of the following: public switched telephone network (PSTN), public or private data network, local area network (LAN), metropolitan area network (MAN), wide area network (WAN), local, regional, or global communications or computer network (such as the Internet, wired or wireless network), corporate intranet, or any other suitable communications link, including combinations thereof.

[0056] In some example embodiments, network node 130 may be a core network node that manages the establishment of communication sessions for UE 110 and various other functions. Examples of network node 130 may include a Mobile Switching Center (MSC), MME, Serving Gateway (SGW), Packet Data Network Gateway (PGW), Operations and Maintenance (O&M), Operations Support System (OSS), SON, location node (e.g., Enhanced Serving Mobile Location Center, E-SMLC), location server node, MDT node, etc. UE 110 may exchange certain signals with network node 130 using a Non-Access Stratum (NAS) layer. In NAS signaling, signals between UE 110 and network node 130 can be transparently transmitted over the radio access network. In some example embodiments, radio access node 120 may interface with one or more network nodes 130 via an inter-node interface.

[0057] As used herein, the term "network node or entity" has the full breadth of its common meaning and can correspond to any type of radio access node (or radio network node) or any network node that can communicate with a UE and / or another network node in a cellular or mobile or wireless communication system. Examples of network nodes are NodeB, MeNB, SeNB, and network nodes can belong to a primary cell group (MCG) or secondary cell group (SCG), base station (BS), multi-standard radio (MSR) radio access node such as MSR BS, eNodeB, network controller, radio network controller (RNC), base station controller (BSC), relay, donor node of control relay, base transceiver station (BTS), access point (AP), transport point, transport node, RRU, RRH, node in distributed antenna system (DAS), core network node (e.g., MSC, MME, etc.), O&M, OSS, ad hoc network (SON), location node (e.g., E-SMLC), MDT, test equipment, etc. See below for reference. Figure 3 A more detailed description of example implementations of network nodes.

[0058] In some example embodiments, radio access node 120 may be a distributed radio access node. The components of radio access node 120 and their associated functions may be separated into two main units (or sub-radio network nodes), which may be referred to as a central unit (CU) and a distributed unit (DU). Different distributed radio network node architectures are possible. For example, in some architectures, the DU may be connected to the CU via a dedicated wired or wireless link (e.g., fiber optic cable), while in other architectures, the DU may be connected to the CU via a transport network. Furthermore, the way the various functions of radio access node 120 are separated between the CU(s) and DU(s) may vary depending on the implemented architecture.

[0059] The example wireless communication system is based on an architecture standardized by the 3rd Generation Partnership Project (3GPP). Development based on 3GPP is generally referred to as Long Term Evolution (LTE) of Universal Mobile Telecommunications System (UMTS) Radio Access Technology (RAT). The various development phases of the 3GPP specification are called releases. The latest development of LTE is generally referred to as LTE Advanced (LTE-A). LTE (LTE-A) employs a radio mobility architecture called Evolved Universal Terrestrial Radio Access Network (E-UTRAN) and a core network called Evolved Packet Core (EPC). Base stations in such systems are called evolved or enhanced Node Bs (eNBs) and provide E-UTRAN features to communication equipment, such as user plane packet data aggregation / radio link control / medium access control / physical layer protocols (PDCP / RLC / MAC / PHY) and control plane radio resource control (RRC) protocol termination. Other RAT examples include those provided by base stations in systems based on technologies such as WLAN and / or Global Microwave Access Interoperability (WiMax). Base stations can provide coverage for an entire cell or similar radio service area. The core network components include the Mobility Management Entity (MME), the Serving Gateway (S-GW), and the Packet Gateway (P-GW).

[0060] Examples of suitable communication systems are the 5G / 6G or NR concepts. The network architecture in NR can be similar to that of LTE-A. Base stations in an NR system can be referred to as Next Generation Node Bs (gNBs). Changes in network architecture can depend on support for various radio technologies and more refined Quality of Service (QoS), as well as some on-demand requirements for QoS levels to support Quality of Experience (QoE) from the user's perspective. Furthermore, network-aware services and applications, and service and application-aware networks, can bring changes to the network architecture. These relate to Information-Centric Networking (ICN) and User-Centric Content Delivery Networking (UC-CDN) approaches. NR can use multiple-input multiple-output (MIMO) antennas, more base stations or nodes than LTE (the so-called small cell concept), including macro sites operating in cooperation with smaller stations, and can also employ various radio technologies to achieve enhanced (e.g., better, higher, etc.) coverage and data rates.

[0061] Future networks can leverage Network Functions Virtualization (NFV), a network architecture concept that proposes virtualizing network node functions as "building blocks" or entities that can be operationally connected or linked together to provide services. Virtualized network functions (VNFs) can include one or more virtual machines running computer program code using standard or general-purpose servers instead of custom hardware. Cloud computing or data storage can also be utilized. In radio communications, this could mean that node operations will be performed, at least partially, in servers, hosts, or nodes operatively coupled to a remote radio head. Node operations can also be distributed across multiple servers, nodes, or hosts. It should also be understood that the division of labor between core network operations and base station operations may differ from, or even not exist, in LTE.

[0062] An example 5G core network (CN) includes functional entities. The CN connects to the UE via the radio access network (RAN). The UPF (User Plane Function), whose role is called the PSA (PDU Session Anchor), is responsible for forwarding frames back and forth between the DN (Data Network) and the tunnel to the UE established through the 5G network to exchange services with the data network (DN). The UPF is controlled by the SMF (Session Management Function), which receives policies from the PCF (Policy Control Function). The CN may also include the AMF (Access and Mobility Function).

[0063] Generally, all concepts disclosed in this document can be applied to different communication networks, including but not limited to LTE, LTE-A, 5G, 5G Advanced, 6G and other future or already implemented networks.

[0064] Figure 2 This is a schematic diagram of an example wireless device UE 110 according to certain example embodiments. UE 110 may include one or more of at least a transceiver 210, at least a processor 220, at least a memory 230, and at least a network interface 240. In some example embodiments, transceiver 210 facilitates (e.g., transmitting and receiving wireless signals to and from radio access node 120 via transmitter (Tx), receiver (Rx), and antenna (antenna). Processor (Tx) 220 executes instructions to provide some or all of the functions described herein provided by the wireless device / entity or UE, and memory 230 stores the instructions executed by processor (Tx) 220. In some embodiments, processor (Tx) 220 and memory 230 form a processing circuitry system.

[0065] The processors 220 may include any suitable combination of hardware for executing instructions and manipulating data to perform some or all of the functions described in the wireless device or entity, such as the functions of the UE 110 described herein. In some embodiments, for example, the processors 220 may include one or more computers, one or more central processing units (CPUs), one or more microprocessors, one or more application-specific integrated circuits (ASICs), one or more field-programmable gate arrays (FPGAs), and / or other logic.

[0066] Memory 230 is generally operable to store instructions, such as computer programs, software, applications including one or more of logic, rules, algorithms, code, tables, etc., and / or other instructions executable by processor 220. Examples of memory 230 include computer memory (e.g., random access memory (RAM) or read-only memory (ROM)), mass storage media (e.g., hard disk), removable storage media (e.g., optical disc (CD) or digital video disc (DVD)), and / or any other volatile or non-volatile, non-transitory computer-readable and / or computer-executable memory device for storing information, data, and / or instructions that can be used by processor 220 of UE 110. For example, memory 230 includes computer program code that causes processor 220 to perform processing according to any corresponding method (or part thereof) described herein.

[0067] Network interface 240 is communicatively coupled to processor 220 and can refer to any suitable device operable to receive input for UE 110, send output from UE 110, perform appropriate processing on the input or output or both, communicate with other devices or any combination thereof. Network interface 240 may include appropriate hardware (e.g., port, modem, network interface card, etc.) and software, including protocol conversion and data processing capabilities, for communication over a network.

[0068] Other example embodiments of UE 110 may include Figure 2 Additional components, other than those shown, may be responsible for providing certain aspects of the functionality of the wireless device, including any of the functions described herein and / or any additional functions (including any functions supporting the mechanisms according to this disclosure). For example, UE 110 may include input devices and circuitry, output devices, and one or more synchronization units or circuits, which may be part of processor(s)220. Input devices include mechanisms for inputting data into UE 110. For example, input devices may include input mechanisms such as a microphone, input element, display, etc. Output devices may include mechanisms for outputting data in audio, video, and / or hardcopy formats. For example, output devices may include speakers, displays, etc.

[0069] In some example embodiments, the wireless device UE 110 may include a series of modules configured to implement the functions of the wireless device described herein.

[0070] It should be understood that various modules can be implemented as a combination of hardware and software, for example Figure 2 The UE 110 shown includes a processor, memory, and (multiple) transceivers. Some example embodiments may also include additional modules to support additional and / or optional functions.

[0071] Figure 3 This is a schematic diagram of an example radio access node 120 or network node or entity 130 (e.g., a base station or base unit) according to certain example embodiments. The radio access node 120 or network node or entity 130 may include one or more of at least one transceiver 310, at least one processor 320, at least one memory 330, and at least one network interface 340. In some example embodiments, the transceiver(s) 310 facilitates the transmission of radio signals to and from a wireless device (such as UE 110) and the reception of radio signals from the wireless device (such as UE 110) (e.g., via multiple transmitters (Tx), multiple receivers (Rx), and multiple antennas). The processor(s) 320 execute instructions to provide some or all of the functions described herein provided by the radio access node 120 or network node or entity 130, and the memory 330 stores the instructions executed by the processor 320. In some example embodiments, the processor(s) 320 and the memory 330 form a processing circuitry system. Multiple network interfaces 340 can transmit signals to back-end network components such as gateways, switches, routers, the Internet, the Public Switched Telephone Network (PSTN), core network nodes, or radio network controllers.

[0072] Processor 320 may include any suitable combination of hardware for executing instructions and manipulating data to perform some or all of the functions described in the radio access node 120 or network node or entity 130, such as those described herein. In some example embodiments, processor(s) 320 may include one or more computers, one or more central processing units (CPUs), one or more microprocessors, one or more application-specific integrated circuits (ASICs), one or more field-programmable gate arrays (FPGAs), and / or other logic.

[0073] Memory 330 is generally operable to store instructions, such as computer programs, software, applications including one or more of logic, rules, algorithms, code, tables, etc., and / or other instructions executable by processor(s) 320. Examples of memory 330 include computer memory (e.g., random access memory (RAM) or read-only memory (ROM)), mass storage media (e.g., hard disk), removable storage media (e.g., optical disc (CD) or digital video disc (DVD)), and / or any other volatile or non-volatile, non-transitory computer-readable and / or computer-executable memory device for storing information. For example, memory 330 includes computer program code that causes processor 320 to perform processing according to any corresponding method (or part thereof) described herein.

[0074] In some example embodiments, network interface(s) 340 are communicatively coupled to processor(s) 320 and may refer to any suitable device operable to receive input for radio access node 120 or network node or entity 130, transmit output from radio access node 120 or network node or entity 130, perform appropriate processing on the input or output or both, communicate with other devices, or any combination thereof. Network interface 340 may include appropriate hardware (e.g., port, modem, network interface card, etc.) and software, including protocol conversion and data processing capabilities, for communication over a network.

[0075] Other example embodiments of radio access node 120 or network node or entity 130 may include Figure 3 Additional components beyond those shown may be responsible for providing certain aspects of the node's functionality, including any of the functions described herein and / or any additional functions (including any functions that support the solutions described herein). Various different types of radio access nodes or network nodes may include components that have the same physical hardware but are configured (e.g., via programming) to support different radio access technologies, or may represent partially or completely different physical components.

[0076] With reference Figure 3 The processors, interfaces, and memories described may be included in other nodes or entities (such as UE 110, radio access node 120, etc.). Other nodes or entities may optionally include or exclude radio interfaces (such as...). Figure 3 (The transceivers described in the text).

[0077] In some example embodiments, radio access node 120 or network node or entity 130 may include a series of modules configured to implement the functions of radio access node 120 or network node or entity 130 as described herein.

[0078] It should be understood that various modules can be implemented as a combination of hardware and software, for example, Figure 3 The radio access node 120 or network node or entity 130 shown includes (multiple) processors, memories, and (multiple) transceivers. Some example embodiments may also include additional modules to support additional and / or optional functions.

[0079] It should be noted that all concepts described herein, though described in a particular manner or context, may be applied more generally, for example, in another particular manner and context, as will be apparent to those skilled in the art.

[0080] Traditional 3GPP communication systems provide a mechanism by which a base unit can redirect a UE in the RRCCONNECTED state to another cell, including an NR cell or an EUTRA cell. This is particularly useful when the base unit realizes that the service requested by the UE cannot be handled after the RRC connection setup is complete. However, in 5G, this is a rather slow procedure that results in significant signaling overhead and latency, at least in part due to the security requirements imposed on the exchange of RRC messages.

[0081] Figure 4 This is a message sequence diagram illustrating the traditional procedure for establishing a secure RRC connection for a UE. The procedure begins in step 1 with the UE, in RRC_IDLE CM-IDLE mode, sending an RRCSetupRequest message to the gNB. In step 2, the gNB responds with an RRCSetup message, which includes configuration for SRB1. SRB1 is used to carry RRC signaling messages and NAS messages between the UE and the gNB to ensure that control plane communications are managed securely and efficiently. Once SRB1 is established, the UE transitions to RRC_CONNECTED mode and responds with an RRCSetupComplete message in step 2a.

[0082] The RRCSetupComplete message includes an initial NAS message, such as an attachment request or tracking area update, which is forwarded by the gNB to the AMF in step 3, thereby transitioning the UE to CM-CONNECTED mode. Once the UE is in CM-CONNECTED mode, optional NAS messages can be exchanged between the core network (AMF) and the UE via a downlink / uplink NAS transmission mechanism. This mechanism involves the gNB receiving NAS messages from the core network / AMF in the downlink direction and forwarding them to the UE via a DLInformationTransfer message (steps 4 and 4a), and receiving UPInformationTransfer messages from the UE in the uplink direction and forwarding them to the core network / AMF (steps 5 and 5a).

[0083] In step 3, the gNB can request the AMF via an Initial UE Message (NGAP: InitialUEMessage) to set the UE context using the optional parameter "UE Context Request". This forces the AMF to send an Initial Context Setup (NGAP: InitialContextSetup) request to the gNB in ​​step 6. The Initial Context Setup includes the security keys required to establish AS security and optionally includes UE radio capabilities and / or UE security capabilities. Based on this information, the gNB can configure AS security with the UE. Specifically, in step 7, the gNB sends a Security Mode Command message to the UE to initiate a secure communication process by setting the security context. This message commands the UE to activate specific encryption and integrity protection algorithms for secure communication. In step 7a, a Security Mode Completion message sent from the UE to the gNB confirms the successful application of the security parameters specified in the Security Mode Command. This message indicates that the UE has correctly configured the selected encryption and integrity protection algorithms and is now ready to continue secure communication. At this point, AS security has been successfully established.

[0084] After AS security is established, messages requiring encryption and / or integrity protection can be securely exchanged between the UE and gNB, such as RRC connection reconfiguration messages for modifying radio bearer configurations, including adding, modifying, or releasing bearers (as shown in steps 8 and 8a); RRC connection release messages (not shown) for releasing RRC connections and transitioning the UE to idle mode; and RRC measurement reports containing measurement results from the UE, which help the network make decisions regarding handover and other optimizations (not shown). Finally, in step 9, the gNB sends an initial context setup response to notify the AMF that the setup procedure is complete.

[0085] When the gNB intends to redirect the UE to another cell, for example because the gNB cannot process the UE's service request, the RRC release message, including redirection information, can only be sent after AS security is established. Similarly, when the gNB intends to hand over the UE to another cell, for example because the current cell does not support the service requested by the UE, the message containing the measurement configuration for the UE can only be sent after AS security is established. As another example, there are cases where the gNB intends to configure the UE for exploratory handover, including the RRC reconfiguration message for the UE configuration for exploratory handover, which can only be sent after AS security is established. However, AS security can only be established after the gNB is provided with a security key. As mentioned above, providing the gNB with a security key for AS security is a rather slow process, resulting in significant delays in redirection and handover.

[0086] Furthermore, there may be situations where the gNB wants to enable AS security for the UE when only SRB1 is established. In the first example, the gNB wants to redirect the UE to a different cell based on the service the UE is trying to access (e.g., voice or video call service). However, in order for the gNB to redirect the UE to a different carrier or notify the UE of cell reselection priority via the RRC:RRCRelease procedure, an AS security activation procedure must be completed. This is because without AS security activation, the RRC release message cannot be encrypted, and transmitting these IEs to the UE without AS security activation is not allowed. Security activation in the access network is only possible when a security key is received from the core network. If the gNB uses the traditional "UE context request" option in NGAP:InitialUEMessage, the AMF may attempt to establish a PDU session for a service that the gNB does not support.

[0087] In the second example, the UE is in RRC connection mode, where only SRB1 is established. The AMF does not enable secure mode for the UE because the connection is only used for NAS signaling. However, the gNB may want to redirect the UE or provide it with a different set of cell reselection priorities to allow subsequent connections to different cells via RRC release. However, the RRC release message needs to be encrypted and can only be sent after AS security is enabled.

[0088] In the third example, exploratory handover is a concept that provides a solution for exploring different handover configurations or methods in a non-intrusive, uninterrupted manner. For a UE with a signaling-only connection, only SRB1 is established, not SRB2 / (multiple) DRBs. Since NAS security has been established, NAS messages can only be securely exchanged between the UE and the MM NF (AMF). However, in the case of exploratory handover, RRC reconfiguration must be sent from the RAN to the UE, which is not allowed because AS security has not yet been established. In legacy communication systems, especially in 3GPP new radios, the core network should send the AS security key and SRB2 / DRB context in the NGAP: Initial Context Setup Request message. However, in the case of a signaling-only connection, this message is not sent from the core network to the RAN. Therefore, AS security cannot be established, thus preventing secure exchange of RRC reconfiguration.

[0089] Therefore, a solution is needed that allows the RAN to explicitly request security key information from the core network, which the RAN can then use to dynamically enable AS security for the UE. A solution is also needed to improve redirection and handover latency without compromising security, particularly when the gNB intends to redirect or handover the UE to another cell immediately after RRC connection setup.

[0090] To address these issues, a specific approach of the present invention provides a mechanism by which a gNB can request security-related information only from the core network, particularly without triggering bearer setup or PDU session establishment.

[0091] In embodiments of the present invention, the base station is configured to perform an RRC setup procedure with the UE, and after successfully completing the RRC setup procedure, to send a security key request message to the core network. The security key request message includes indications that the base station intends to immediately release the UE, and / or not establish a PDU session for the UE, and / or that settings for the UE's radio bearers will be suspended. The base station is also configured to receive a security key information message from the core network in response to the security key request message. The security key information message includes security key information indicating a security key for establishing AS security for the UE.

[0092] According to another aspect of the invention, by simplifying the exchange of messages between the UE and gNB for establishing AS security and initiating redirection or handover, redirection and handover delays are reduced.

[0093] In an embodiment of the present invention, the UE is configured to perform an RRC setup procedure with the base station, and after the RRC setup procedure has been successfully completed, receive an RRC message from the base station. The RRC message includes security information and encrypted redirection information, the security information being the information required by the user equipment to decrypt the encrypted redirection information.

[0094] In another embodiment of the invention, the base station is configured to perform an RRC setup procedure with the user equipment, and after the RRC setup procedure has been successfully completed, to send an RRC message to the user equipment, the RRC message including security information and encrypted redirection information, the security information being the information required by the user equipment to decrypt the encrypted redirection information.

[0095] In another embodiment of the invention, the UE is configured to perform an RRC setup procedure with the base station, and after the RRC setup procedure has been successfully completed, receive an RRC message from the base station, the RRC message including security information and encrypted measurement configuration information, the security information being the information required by the user equipment to decrypt the encrypted measurement configuration information, the measurement configuration information indicating the measurement to be performed by the user equipment.

[0096] In another embodiment of the invention, the base station is configured to perform an RRC setup procedure with the user equipment, and after the RRC setup procedure has been successfully completed, to send an RRC message to the user equipment. The RRC message includes security information and encrypted measurement configuration information, the security information being the information required by the user equipment to decrypt the encrypted measurement configuration information, which indicates the measurement to be performed by the user equipment.

[0097] Figure 5 This is a message sequence diagram of a program for requesting security key information according to an embodiment of the present invention.

[0098] In step 1, the RAN node (e.g., base station, base unit, gNB, or equivalent entity) sends an initial UE message to the core network (e.g., MMNF, AMF, or equivalent entity). The initial UE message may be sent in response to the successful completion of the RRC setup procedure by the UE, particularly in response to an RRC setup completion message received from the UE. The initial UE message may include a first NAS message received from the UE and the RRC setup completion message. According to this embodiment, the initial UE message includes an indication that the base station intends to immediately release the UE. Additionally or alternatively, the initial UE message includes an indication that no radio bearer is set for the UE (or at least no radio bearer other than SRB1) and / or that no PDU session is established for the UE. Specifically, the initial UE message may include the information element "Fast Security Activation Request," which is set to a predetermined value (e.g., True) to indicate that the base station intends to immediately release the UE, not set a radio bearer for the UE, and / or not establish a PDU session for the UE; otherwise, it is set to another predetermined value (e.g., False) or omitted.

[0099] Upon receiving the initial UE message with the indication set, the core network responds in step 2 with a security key information message. This message includes security key information indicating the security keys used to establish AS security for the UE. The security key information message may include some or all of the security information typically included in the initial context setup request message, including the security keys required to establish AS security. The security key information message may also include security capability information indicating the UE's security capabilities and / or radio capability information indicating the UE's radio capabilities.

[0100] The core network sends a security key information message in an immediate / direct response to an initial UE message with a fast security activation request indication (set without taking any further action regarding the establishment of an additional radio bearer or PDU session). The core network may specifically suspend processing requests (such as registration requests or service requests) contained in a first NAS message that may be included in the initial UE message.

[0101] If the RAN identifies, for example, via the "EstablishmentCause" IE in the RRC setup request that the service the UE is attempting to establish is unsupported, the RAN can notify the core network in the initial UE message that only security key information is required, and any bearer setup initiated by the core network for the UE should be suspended. For example, the RAN node may not support voice or video calls, or may have already decided to offload voice or video calls to another RAN node. When the RAN node receives an RRC setup request from a UE requesting voice or video call service, it can decide to redirect the UE to another cell or RAN node. To do this, the RAN node can set a fast security activation request indication in the initial UE message to notify the core network that only security key information is required, and any bearer establishment by the UE should be suspended. Based on the security key information message received from the core network, the RAN can establish AS security and release the UE by redirection or handover to a cell / node that supports the service. In this way, fast redirection can be achieved while avoiding any unnecessary resource setup by either the RAN or the core network.

[0102] In this way, the RAN node is quickly provided with the information needed to establish AS security with the UE.

[0103] Figure 6 This is a message sequence diagram of a program for requesting security key information according to another embodiment of the present invention.

[0104] In step 1, the RAN node (e.g., a base station, base cell, gNB, or equivalent entity) sends a security key information request message to the core network (e.g., an MMNF, AMF, or equivalent entity). In step 2, the core network responds to the security key information request message by sending a security key information message to the RAN node. This security key information message includes security key information indicating the security key used to establish AS security for the UE. The security key information message may include some or all of the security information typically included in the initial context setup request message, including the security key required to establish AS security. The security key information message may also include security capability information indicating the UE's security capabilities and / or radio capability information indicating the UE's radio capabilities.

[0105] The Security Key Information Request (SKI) message differs from the traditional Initial UE message sent to forward the Initial UE message (First NAS message) from the UE to the core network to establish a signaling connection between the UE and the core network. Instead, the SKI message can be sent from the RAN node to the core network even when a signaling connection between the UE and the core network is already in place. This allows the RAN node to establish AS security, even after the Initial UE message has been sent to the UE, and even if the core network has not triggered initial context setup for the UE. For example, this can be applied to signaling-only connections, such as SMS services. However, other application scenarios exist, such as the exploratory handover described above, where the RAN node needs to establish AS security.

[0106] Figure 7 This is a message sequence diagram of a procedure for notifying the core network of successful AS security activation according to another embodiment of the present invention.

[0107] By using the above combination Figure 5 or Figure 6 After the security information received by the RAN node successfully activates the UE's AS security, the RAN node can send an AS security activation indication to the core network to indicate that AS security has been successfully established. Upon receiving this message, the core network can proceed with any bearer settings it has suspended for the UE, such as in response to the fast security activation request indication set in the initial UE message.

[0108] Now refer to Figure 8 and Figure 9 Describe the techniques used to achieve fast redirection of the UE.

[0109] To release a UE's RRC connection, a RAN node (e.g., a base station, base cell, gNB, or equivalent entity) can send an RRC release message to the UE. The RRC release may include redirection information indicating the cell, carrier, or RAN node the UE should attempt to connect to. However, for security reasons, RRC release messages may only be allowed to be sent in encrypted (ciphered) and / or integrity-protected form. Therefore, successfully completing the AS security setup procedure may be a prerequisite for sending an RRC release message.

[0110] To establish AS security, the RAN node can send a security mode command message to the UE. The security mode command message includes information required by the UE to establish AS security, including information indicating the encryption and integrity protection algorithms to be used and which keys to use. Upon receiving the security mode command message, the UE activates AS security by configuring its security algorithms based on the security information contained in the message, and confirms successful AS security setup by sending a security mode completion message to the RAN node.

[0111] The exchange of separate commands and acknowledgment messages between the RAN node and the UE can cause delays in releasing the RRC connection and redirecting the UE to another cell. To reduce this delay, a technique is provided to simultaneously perform secure mode activation and RRC release. This aspect of the invention can involve the joint transmission of encrypted redirection information and the security information required for the UE to decrypt the redirection information. This aspect can also involve transmitting acknowledgments from the UE to the gNB only at a lower protocol layer, thereby further accelerating RRC release.

[0112] Figure 8 This is a message sequence diagram of a procedure for simultaneously releasing RRC and activating safe mode according to an embodiment of the present invention.

[0113] According to this embodiment, in step 1, the RAN node sends a security mode command message to the UE. In addition to security information, the security mode command message also includes information contained in the RRC release message, including a command to release the current RRC connection and redirection information. Therefore, the RRC release and redirection information can be sent together with the security mode command, appended to the security mode command, or otherwise included within the security mode command. Specifically, an encrypted (and optionally integrity-protected) RRC release message including redirection information can be carried over the RRC security mode command message. Upon receiving the RRC security mode command message carrying the RRC release message, the UE can configure AS security and process the encrypted RRC release message, i.e., decrypt the encrypted RRC release message and the redirection information contained therein, verify its integrity and / or authenticity (if applicable), release the RRC connection to the current cell, and attempt to establish an RRC connection at another cell (or carrier or gNB), as indicated by the redirection information. Therefore, security mode activation and RRC release are performed simultaneously. This method makes the separate transmission of RRC safe mode commands and RRC release messages redundant, thereby enabling rapid UE release.

[0114] In step 2, the UE can use the release information to confirm the successful reception and processing of the secure mode command. According to another aspect of the invention, the confirmation is sent at a lower protocol layer (such as the MAC layer or RLC layer), thereby making the transmission of the dedicated secure mode completion message redundant.

[0115] Figure 9 This is a message sequence diagram of a procedure for simultaneously releasing RRC and activating safe mode according to another embodiment of the present invention.

[0116] According to this embodiment, the security information required by the UE to decrypt the RRC release message can also be sent along with the encrypted RRC release message (e.g., carried on top of the encrypted RRC release message), appended to the encrypted RRC release message, or otherwise included in the encrypted RRC release message. The security information itself is not encrypted, so the UE can use this information after receiving the RRC release message to decrypt the encrypted portion of the RRC release message and any redirection information contained therein, verify its integrity and / or authenticity (if applicable), release the RRC connection to the current cell, and attempt to establish an RRC connection at another cell (or carrier or gNB), as indicated by the redirection information. Therefore, security mode activation and RRC release are performed simultaneously. This method makes the separate transmission of the RRC security mode command and the RRC release message redundant, thereby enabling rapid UE release.

[0117] In step 2, the UE can use security information to confirm the successful reception and processing of the RRC release message. According to another aspect of the invention, the confirmation is sent at a lower protocol layer (such as the MAC layer or RLC layer), thereby making the transmission of a dedicated RRC release completion message redundant.

[0118] Now refer to Figure 10 Describe the techniques used to achieve fast switching.

[0119] UE handover preparation may include sending measurement configuration from the RAN node to the UE. Similar to the transmission of the RRC release message described above, the transmission of measurement configuration may also require establishing AS security at the UE.

[0120] The exchange of separate messages for establishing AS security and configuring measurements at the UE results in a delay before a handover can actually be performed. To reduce this delay, a technique is provided for simultaneously performing AS establishment and measurement configuration. This aspect of the invention may involve the joint transmission of encrypted measurement configuration and the security information required by the UE to decrypt the measurement configuration. This aspect may also involve the joint transmission of measurement reports and confirmation of successful AS security establishment.

[0121] Now refer to Figure 10 Embodiments of this aspect of the invention are described below. Figure 10 A message sequence diagram of simultaneous security mode activation and measurement procedures according to another embodiment of the present invention is shown.

[0122] According to this embodiment, switching information (e.g., measurement configuration) may be sent together with the security mode command message, appended to the security mode command message, or otherwise included in the security mode command message. Specifically, the encrypted (and optionally integrity-protected) measurement configuration may be sent with the security mode command message. Figure 10 In step 1, the (downlink) RRC security mode command message sent from the gNB to the UE is carried along with it.

[0123] After receiving the security mode command message in step 2, the UE is able to configure AS security and process encrypted handover information, that is, decrypt the encrypted measurement configuration, verify its integrity and / or authenticity (if applicable), perform measurements according to the decrypted measurement configuration, and prepare a measurement report indicating the measurement results.

[0124] In step 3, the UE can send a measurement report to the RAN node. According to an optional aspect of this embodiment, this can be achieved by sending the measurement report along with, appending to, or otherwise including in the RRC security mode completion message confirming successful AS security activation by the UE. Specifically, the measurement report can be carried over the RRC security mode completion message. Based on the measurement report, the gNB can then trigger a handover.

[0125] Therefore, the safety mode activation and measurement configuration procedures are executed simultaneously. This approach makes the separate transmission of RRC safety mode commands / completion messages and measurement configuration / reports redundant.

[0126] Those skilled in the art will clearly understand that the above combination Figures 5 to 10 The various functions, operations, features, etc., of the described program can be applied to a corresponding other program. That is, the teachings of the above embodiments can be appropriately combined with each other. Specific examples of such combinations are provided below.

[0127] Figure 11 This is a message sequence diagram of an exemplary procedure for AS security activation with redirected RRC release when the service requested by the UE is unsupported and the UE's radio capabilities can be obtained from the core network. This example is based on a combination of Figure 5 The described embodiments of the program for requesting security key information, and the combination thereof Figure 8 and Figure 9 The described embodiment is a procedure for simultaneously establishing AS security and releasing UE.

[0128] exist Figure 11 In the example procedure shown, it is assumed that voice service is not enabled at the RAN (see step 1), the UE is attempting to establish an RRC connection, and the IE “establishmentCause” is set to “mo-voice” (see step 2). It is also assumed that the UE’s radio capabilities are known at the core network and are transmitted to the gNB (see step 5).

[0129] In step 1 of the procedure, voice service is disabled at the gNB. However, the UE successfully completes the RRC setup procedure, and the IE “establishmentCause” in the RRCSetupRequest is set to “mo-voice” (step 2). Therefore, the UE is in RRC-CONNECTED mode, and SRB1 is established for the UE.

[0130] Since voice service is not supported, the gNB decides to release the UE in step 3, intending to redirect it to another carrier. For this, AS security needs to be enabled for the UE. Therefore, in step 4, the gNB triggers NGAP:InitialUEMessage, with the IE "Fast Security Activation Request" set to true, to indicate to the AMF that the gNB intends to release the UE immediately and / or may attempt to postpone PDU session establishment and / or (attached) radio bearer settings for the UE.

[0131] In step 5, the AMF responds with a Security Key Information message (NGAP: SecurityKeyInfo), which includes security key information indicating the security key required for establishing AS security for the UE, the UE's security capabilities (UE security capability information), and the UE's radio capabilities (UE radio capability information).

[0132] In step 6, based on the UE's radio capabilities, the gNB selects a carrier to which the UE can be redirected. Furthermore, based on the security key information and the UE's security capabilities, the gNB successfully establishes AS security for the RAN side. The gNB then encrypts (and optionally insulates) the RRC message using the established encryption and (optionally) integrity protection algorithms. The RRC message includes redirection information indicating the selected carrier. However, a prerequisite for sending the encrypted RRC message is that AS security is also established on the UE side. Traditionally, this is achieved by sending an RRC security command message from the gNB to the UE, which includes information specifying the encryption and integrity protection algorithms to be used (see step 7). In step 8, once the UE's security mode completion message (not shown) has been received, an encrypted RRC release message can be sent to confirm the successful establishment of AS security on the UE side.

[0133] The separate exchange of command and acknowledgment messages between the gNB and the UE also leads to delays in the executable redirection. According to another aspect of the invention, redirection delays are reduced by simplifying the protocols used to establish AS security and redirect the UE. This aspect may involve the joint transmission of encrypted redirection information and the security information required by the UE to decrypt the redirection information. Therefore, at the UE, security mode activation and RRC release can be performed simultaneously, thereby quickly releasing the UE. This aspect may also involve transmitting acknowledgments from the UE to the gNB only at lower protocol layers, thereby further accelerating RRC release.

[0134] According to embodiments of the present invention, the information contained in the RRC release message (including a command to release the current RRC connection and redirection information) may also be sent together with the RRC security mode command, appended to the RRC security mode command, or otherwise included in the RRC security mode command. Specifically, an encrypted (and optionally integrity-protected) RRC release message including redirection information may be carried over... Figure 11 The RRC security mode command message is shown in step 7. Upon receiving the RRC security mode command message, the UE can configure AS security and process the encrypted RRC release message, i.e., decrypt the encrypted RRC release message and the redirection information contained therein, verify its integrity and / or authenticity (if applicable), release the RRC connection to the current cell, and attempt to establish an RRC connection at another cell (or carrier or gNB), as indicated by the redirection information. Therefore, security mode activation and RRC release are performed simultaneously. This method makes the separate transmission of the RRC security mode command and RRC release message redundant. Therefore, the separate transmission of the RRC release message can be omitted. Figure 11 Step 8 in the process.

[0135] According to another embodiment of the invention, the security information required by the UE to decrypt the RRC release message can also be sent together with the encrypted RRC release message (e.g., carried with the encrypted RRC release message), appended to the encrypted RRC release message, or otherwise included in the encrypted RRC release message. The security information itself is not encrypted, so the UE can use this information after receiving the RRC release message to decrypt the encrypted portion of the RRC release message and the redirection information contained therein, verify its integrity and / or authenticity (if applicable), release the RRC connection to the current cell, and attempt to establish an RRC connection at another cell (or carrier or gNB), as indicated by the redirection information. Therefore, security mode activation and RRC release are performed simultaneously. This method makes the separate transmission of the RRC security mode command and the RRC release message redundant. Therefore, the separate transmission of the RRC security mode command can be omitted. Figure 11 Step 7 in the process.

[0136] Refer again Figure 11 The UE releases the RRC connection to the current cell and attempts to establish an RRC connection in another cell (or carrier or gNB), as indicated by the redirection information in step 9. This step can be performed regardless of how the UE obtains the security information and release information (the instruction to release the RRC connection with the redirection information).

[0137] In step 10, the UE can confirm the successful reception of security and release information, that is, the successful reception of a security mode command with release information or the successful reception of an RRC release message with security information. According to another aspect of the invention, the confirmation is sent at a lower protocol layer (such as the MAC layer or RLC layer).

[0138] In step 11, the gNB initiates and successfully releases the UE's NG logical connection, for example, by executing the NGAP UE context release procedure.

[0139] Figure 12 This is a message sequence diagram illustrating the exemplary processing for AS security activation with redirected RRC release when the service requested by the UE is unsupported and the UE's radio capabilities are unavailable. This example is based on [the following text is incomplete and requires further context: "in combination with..."] Figure 5 The described embodiment is a program for requesting security key information.

[0140] exist Figure 12 In the procedure shown, it is assumed that voice service is not enabled at the RAN (see step 1), the UE is attempting to establish an RRC connection, and the IE "establishmentCause" is set to "mo-voice" (see step 2). It is also assumed that the UE's radio capabilities are unknown at the core network.

[0141] In step 1 of the procedure, voice service is disabled at the gNB. However, the UE successfully completes the RRC setup procedure, and the IE “establishmentCause” in the RRCSetupRequest is set to “mo-voice” (step 2). Therefore, the UE is in RRC-CONNECTED mode, and SRB1 is established for the UE.

[0142] Since voice service is not supported, the gNB decides to release the UE in step 3, intending to redirect it to another carrier. For this, AS security needs to be enabled for the UE. Therefore, in step 4, the gNB triggers NGAP:InitialUEMessage, with the IE "Fast Security Activation Request" set to true, to indicate to the AMF that the gNB intends to release the UE immediately and / or may attempt to postpone PDU session establishment and / or (attached) radio bearer settings for the UE.

[0143] In step 5, the AMF responds with a Security Key Information message (NGAP: SecurityKeyInfo), which includes security key information indicating the security keys required to establish AS security for the UE and the UE's security capabilities (UE security capability information). However, the UE's radio capabilities (UE radio capability information) are not available at the core network and are therefore not included in the Security Key Information message.

[0144] In step 6, an RRC security mode command procedure is executed between the UE and the RAN. This procedure may involve the exchange of conventional messages, including the security mode command message and security mode completion message described above. As a result, AS security is established, meaning the UE is configured with encryption and integrity protection.

[0145] In step 7, UE capability information is exchanged between the UE and the gNB, for example via the traditional RRC: UE Capability Query procedure. The gNB notifies the AMF of the UE's capabilities via the NGAP: UECapabilityInformationIndication message.

[0146] At this point, the UE's radio capabilities are available at the gNB. In step 8, based on the received UE radio capabilities, the gNB determines the carrier (or cell or gNB) to which the UE should be redirected.

[0147] In step 9, the gNB sends an encrypted (and optionally integrity-protected) RRC release message to the UE containing redirection information. The redirection information is related to the result of the decision process in step 8 and indicates the carrier (or cell or gNB) to which the UE is redirected.

[0148] In step 10, the gNB initiates and successfully releases the UE's (ng logical) connection, for example by executing the NGAP UE context release procedure.

[0149] Figure 13 This is a message sequence diagram of an exemplary procedure for AS security activation during handover when the service requested by the UE is unsupported and the UE's radio capabilities are available. This example is based on a combination of... Figure 5 The described embodiments of the program for requesting security key information, and the combination thereof Figure 10 The described embodiments are combined AS safety and measurement procedures.

[0150] exist Figure 13In the example procedure shown, it is assumed that voice service is not enabled at the RAN (see step 1), the UE is attempting to establish an RRC connection, and the IE “establishmentCause” is set to “mo-voice” (see step 2). It is also assumed that the UE’s radio capabilities are known at the core network and are transmitted to the gNB (see step 5).

[0151] In step 1 of the procedure, voice service is disabled at the gNB. However, the UE successfully completes the RRC setup procedure, and the IE “establishmentCause” in the RRCSetupRequest is set to “mo-voice” (step 2). Therefore, the UE is in RRC-CONNECTED mode, and SRB1 is established for the UE.

[0152] Since voice services are not supported, the gNB decides in step 3 to trigger a handover of the UE to a cell where the UE can access the desired service. For this, AS security needs to be enabled for the UE. Therefore, in step 4, the gNB triggers NGAP:InitialUEMessage, setting the IE "Fast Security Activation Request" to true, to indicate to the AMF that the gNB intends to immediately release the UE and / or may attempt to postpone PDU session establishment and / or (attached) radio bearer settings for the UE.

[0153] In step 5, the AMF responds with a Security Key Information message (NGAP: SecurityKeyInfo), which includes security key information indicating the security key required for establishing AS security for the UE, the UE's security capabilities (UE security capability information), and the UE's radio capabilities (UE radio capability information).

[0154] Based on the security key information and the UE's security capabilities, the gNB successfully establishes AS security for the RAN side. The gNB then encrypts (and optionally insulates) the measurement configuration using the established encryption and (optionally) integrity protection algorithms. However, a prerequisite for sending the encrypted measurement configuration is that AS security is also established for the UE side. Traditionally, this is achieved by sending an RRC security command message from the gNB to the UE, which includes information specifying the encryption and integrity protection algorithms to be used (see step 6). In step 7, once the UE's security mode completion message is received, the encrypted measurement configuration can be sent to confirm the successful setup of AS security on the UE side.

[0155] However, the exchange of multiple individual messages between the gNB and the UE also leads to delays in handover execution. According to another aspect of the invention, handover delays are reduced by combining procedures for establishing AS security with measurement procedures at the UE. This aspect may involve the joint transmission of encrypted measurement configuration and required security information from the gNB to the UE, and / or the joint transmission of measurement reports from the UE to the gNB and confirmation of successful AS security establishment.

[0156] According to embodiments of the invention, switching information (e.g., measurement configuration) may be sent together with, appended to, or otherwise included in the RRC security mode command message. Specifically, encrypted (and optionally integrity-protected) measurement configuration may be carried on... Figure 13 In step 6, the (downlink) RRC security mode command message is sent from the gNB to the UE.

[0157] After receiving the RRC security mode command message in step 6, the UE is able to configure AS security and process encrypted handover information, namely, decrypt the encrypted measurement configuration, verify its integrity and / or authenticity (if applicable), perform measurements according to the decrypted measurement configuration, and prepare a measurement report to indicate the results of the measurements.

[0158] In step 7, the UE confirms the successful activation of AS security by sending an RRC security mode completion message to the gNB.

[0159] According to embodiments of the present invention, the measurement report may be sent together with the RRC safe mode completion message, or appended to the RRC safe mode completion message, or otherwise included in the RRC safe mode completion message. Specifically, the measurement report may be carried with Figure 13 The (uplink) RRC security mode completion message shown in step 7.

[0160] Therefore, the safety mode activation and measurement configuration procedures are executed simultaneously. This approach makes the separate transmission of RRC safety mode commands / completion messages and measurement configuration / reports redundant.

[0161] In step 8, the UE is switched to a cell that supports voice services based on the measurement report.

[0162] In step 10, the gNB notifies the AMF of the successful establishment of AS security for the UE. Therefore, the AMF can proceed with the setup for establishing PDU sessions and / or (additional) radio bearers for the UE, which were suspended in response to the "Fast Security Activation Request" instruction received in step 4.

[0163] Figure 14A and Figure 14B A message sequence diagram of an exemplary procedure for AS security activation during exploratory handover is shown. According to an embodiment of the invention, this procedure is based on a dedicated procedure for requesting security key information from the core network and notifying the core network of successful AS security activation.

[0164] In step 1 of this procedure, the UE and gNB successfully completed the RRC setup procedure. Therefore, the UE is in RRC-CONNECTED mode, and SRB1 is established for the UE.

[0165] In step 2, the gNB initiates an NGAP initial UE message to the AMF to establish an NG logical connection for the UE. Step 2 can be followed by an optional step 3, where NAS messages can be exchanged via SRB1.

[0166] In step 4, gNB selects the UE for exploratory handover.

[0167] In step 5, the gNB requests the AMF to provide security key information for the UE. This request can follow the steps outlined above. Figure 6 The program described.

[0168] In step 6, the AMF responds with a Security Key Information message (NGAP: SecurityKeyInfo), which includes security key information indicating the security keys required to establish AS security for the UE and the UE's security capabilities (UE security capability information). The Security Key Information message may also include information indicating the UE's radio capabilities (UE radio capability information).

[0169] In step 7, based on the received security key information and the UE's security capabilities, an RRC security mode command procedure is executed between the UE and the RAN. This procedure may involve the exchange of regular messages, including the security mode command message and security mode completion message described above. As a result, AS security is established, meaning the UE is configured with encryption and (optionally) integrity protection.

[0170] In step 8, the gNB notifies the AMF of the successful establishment of A&S security for the UE. This notification can follow the steps outlined above. Figure 7 The procedure described. Therefore, subsequent RRC messages exchanged between the UE and gNB can be encrypted and optionally protected for integrity.

[0171] If the AMF does not share the UE's radio capability information in step 6, the gNB initiates an RRCUE radio capability query procedure with the UE in step 9, causes the UE to send its radio capability information to the gNB in ​​step 10, and causes the gNB to store the UE's radio capability information and forward it to the AMF in step 11.

[0172] Since AS security is now in place, the gNB can send an RRC reconfiguration message (encrypted and optionally integrity-protected) with an exploratory handover configuration to the UE in step 12. After receiving and decrypting the message, the UE enters exploratory mode.

[0173] In step 13, the UE triggers a measurement report for the cell with the better measurement.

[0174] In step 14, a handover decision is made at the UE based on the measurement report, and handover preparation is performed at the gNB, including admission control in the target cell.

[0175] In step 15, the gNB uses the target cell mobility information to trigger an RRC reconfiguration for the UE. In response, the UE disconnects from the old cell and connects to the target cell.

[0176] In step 16, the UE triggers a measurement report with feedback on the handover.

[0177] In step 17, gNB evaluates the measurement report.

[0178] In step 18, the exploratory switch is released, thereby terminating the exploration in the UE in step 19.

[0179] In step 20, based on this feedback, the handover policy at the old cell is updated at the gNB.

[0180] The functions described above and their related operations, procedures, methods, and processes can be implemented by the corresponding functional elements, entities, modules, units, processors, etc., described below. These functional elements, entities, modules, units, processors, etc. (e.g., implementations of one or more example embodiments) can be implemented in a cloud environment via SDN, NFV / NFVI, etc.

[0181] While various exemplary embodiments are described with reference to operations, procedures, methods, and processes, these exemplary embodiments also encompass corresponding apparatuses, entities, modules, units, network nodes, and / or systems, including their software and / or hardware. For example, such apparatuses may be based on... Figure 2 and Figure 3 This is achieved using the structures shown and described above.

[0182] According to the example embodiment, any one of (at least one) processor, (at least one) memory and (at least one) interface can be implemented as a single module, chip, chipset, circuit system, etc., or one or more of them can be implemented as a common module, chip, chipset, circuit system, etc., respectively.

[0183] As used herein, the term “circuit system” may refer to one or more or all of the following: (a) a hardware circuit implementation only (such as an implementation only in analog and / or digital circuit systems) and (b) a combination of hardware circuits and software, such as (if applicable): (i) a combination of (multiple) analog and / or digital hardware circuits with software / firmware, and (ii) any portion of (multiple) hardware processors (including (multiple) digital signal processors), software, and (multiple) memories having software, which work together to enable a device (such as a mobile phone or a server) to perform various functions, and (c) (multiple) hardware circuits and / or (multiple) processors, such as (multiple) microprocessors or portions thereof, which require software (e.g., firmware) to function, but may be absent when not required to function.

[0184] This definition of circuit system applies to all uses of the term herein, including in any claim. As another example, as used herein, the term circuit system also covers implementations of hardware circuitry or processors (or processors) or portions thereof and their accompanying software and / or firmware. For example, and if applicable to a particular claim element, the term circuit system also covers baseband integrated circuits or processor integrated circuits for mobile devices, or similar integrated circuits in servers, cellular network devices, or other computing or networking devices.

[0185] According to some example embodiments, the system may include any imaginable combination of any depicted or described device and other network elements or functional entities configured to cooperate as described above.

[0186] Generally, it should be noted that, if it is only suitable for performing the functions described in the corresponding section, the corresponding functional blocks or elements according to the various embodiments described herein can be implemented accordingly by any known means in hardware and / or software. The above method steps can be implemented in individual functional blocks or by individual devices, or one or more of the above method steps can be implemented in a single functional block or by a single device.

[0187] Typically, the basic system architecture of a (remote) communication network, including a mobile communication system (some examples of the exemplary embodiments are applicable therein), may include the architecture of one or more communication networks, including (multiple) radio access network subsystems / systems and (multiple) possible core networks. This architecture may include one or more communication network control elements or functions, such as, for example, access network elements, radio access network elements, access service network gateways or base transceiver stations (e.g., base stations, access points, NodeBs (NBs), eNBs, or gNBs), distributed or centralized units that control a corresponding coverage area or (multiple) cells, and one or more communication stations (such as communication elements or functions), such as user equipment or terminal equipment like UEs or other devices with similar functions (e.g., modem chipsets, chips, modules, etc.), which may also be part of a communication-enabled station, element, function, or application, such as a UE, an element or function that can be used in a machine-to-machine communication architecture, or attached as a separate element to such a communication-enabled element, function, or application, capable of communicating via one or more communication beams through one or more channels for transmitting various types of data in multiple access domains. In addition, it may include core network elements or network functions (such as gateway network elements / functions, mobility management entities, mobile switching centers, servers, databases, etc.).

[0188] The general functions and interconnections of the described elements and functions (which also depend on the actual network type) are known to those skilled in the art and are described in the corresponding specifications, and therefore their detailed description is omitted here. It should be understood that, in addition to those described in detail below, a variety of additional network elements and signaling links may be employed to communicate with elements, functions or applications (such as communication endpoints), communication network control elements (such as servers, gateways, radio network controllers), and other elements of the same or other communication networks.

[0189] The communication network architecture considered in the example embodiments may also be able to communicate with other networks, such as the public switched telephone network or the Internet, including the Internet of Things (IoT). The communication network may also be able to support cloud services for virtual network elements or their functions. It should be noted that the virtual network portion of the (remote) communication network may also be provided by non-cloud resources, such as internal networks. It should be understood that network elements and / or corresponding functions of access systems, core networks, etc., can be implemented using any node, host, server, access node, or entity suitable for such purposes. Typically, network functions can be implemented as network elements on dedicated hardware, software instances running on dedicated hardware, or virtualized functions instantiated on a suitable platform (e.g., cloud infrastructure).

[0190] Without altering the ideas or scope of the various example embodiments, any method steps are suitable for implementation as software or in hardware. Such software can be independent of software code and can be specified using any known or future-developed programming language (such as Java, C++, C, and Assembler), as long as the functionality defined by the method steps is preserved. Such hardware can be independent of hardware type and can be implemented using any known or future-developed hardware technology or any combination of these technologies, such as MOS (Metal-Oxide-Semiconductor), CMOS (Complementary MOS), BiMOS (Bipolar MOS), BiCMOS (Bipolar CMOS), ECL (Emitter-Coupled Logic), TTL (Transistor-Transistor Logic), etc., using, for example, ASIC (Application-Specific IC (Integrated Circuit) components, FPGA (Field-Programmable Gate Array) components, CPLD (Complex Programmable Logic Device) components, or DSP (Digital Signal Processor) components. Devices / apparatus may be represented by semiconductor chips, chipsets, or (hardware) modules including such chips or chipsets; however, this does not preclude the possibility that the functionality of a device / apparatus or module is not implemented in hardware but rather implemented as software within a (software) module (such as a computer program or computer program product including executable software code portions for execution / running on a processor). For example, a device may be considered as a device / apparatus, or a component of more than one device / apparatus, whether functionally cooperative or functionally independent but residing in the same device housing.

[0191] Devices and / or units / components or portions thereof may be implemented as a single device, but this does not preclude them from being implemented in a distributed manner throughout the system, provided that the functionality of the device is preserved. Such and similar principles are considered to be known to those skilled in the art.

[0192] Software in the sense of this specification includes software code, which itself includes code components or portions for performing corresponding functions, or computer programs or computer program products, as well as software (or computer programs, computer program products) embodied on tangible media (such as computer-readable (storage) media) on which corresponding data structures or code components / portions are stored, or embodied in signals or chips, potentially during processing.

[0193] Various example embodiments also cover any conceivable combination of the method steps and operations described above, as well as any conceivable combination of the nodes, devices, modules or elements described above, provided that the concepts of the methods and structural arrangements described above are applicable.

[0194] In light of the above, techniques for rapidly establishing AS security are provided. For example, such techniques may include a base station configured to perform an RRC setup procedure with the UE, and after successfully completing the RRC setup procedure, sending a security key request message to the core network. This security key request message includes indications that the base station intends to immediately release the UE, and / or not establish a PDU session for the UE, and / or that settings for the UE's radio bearers will be suspended. The base station may also be configured to receive a security key information message from the core network in response to the security key request message. This security key information message includes security key information indicating a security key used to establish AS security for the UE.

[0195] In view of the above, a technique is provided for requesting security key information when the core network has not triggered the initial context setting of the UE even after sending an initial UE message to the UE. For example, such a technique may include a base station configured to perform an RRC setup procedure with the UE; forwarding an initial UE message from the UE to the core network to establish a signaling connection between the UE and the core network; sending a security key request message to the core network when the signaling connection is in place; and receiving a security key information message from the core network in response to the security key request message, the security key information message including security key information indicating a security key for establishing AS security for the UE.

[0196] In view of the above, techniques for simultaneously releasing RRC and activating secure mode are also provided. For example, such techniques may include configuring the UE to perform an RRC setup procedure with a base station, and after successfully completing the RRC setup procedure, receiving an RRC message from the base station, the RRC message including security information and encrypted redirection information, the security information being the information required by the user equipment to decrypt the encrypted redirection information.

[0197] In view of the above, techniques for combining security modes and measurement procedures are also provided. For example, such techniques may include configuring the UE to perform an RRC setup procedure with a base station, and after the RRC setup procedure has been successfully completed, receiving an RRC message from the base station, the RRC message including security information and encrypted measurement configuration information, the security information being the information required by the UE to decrypt the encrypted measurement configuration information, which instructs the UE on the measurement to be performed.

[0198] Although various exemplary embodiments have been described above with reference to the accompanying drawings, it should be understood that the various exemplary embodiments are not limited thereto. Rather, it will be apparent to those skilled in the art that the various exemplary embodiments can be modified in many ways without departing from the intended scope.

Claims

1. A user equipment, comprising: At least one processor; as well as At least one memory storing instructions that, when executed by the at least one processor, cause the user equipment to at least: Perform the Radio Resource Control (RRC) setup procedure with the base station; as well as After the RRC setup procedure has been successfully completed, an RRC message is received from the base station. The RRC message includes security information and encrypted measurement configuration information. The security information is the information required by the user equipment to decrypt the encrypted measurement configuration information. The measurement configuration information indicates the measurement to be performed by the user equipment.

2. The user equipment according to claim 1, wherein, The RRC message is an RRC security mode command message that includes the security information, and the RRC security mode command message carries the encrypted measurement configuration information.

3. The user equipment according to claim 1 or 2, wherein, When the instruction is executed by the at least one processor, the user equipment causes at least: Use the security information to decrypt the encrypted measurement configuration information; The measurement is performed based on the decrypted measurement configuration information; as well as The system sends a response to the RRC message to the base station, the response including a measurement report indicating the result of the measurement performed by the user equipment. The response is an RRC security mode completion message carrying the measurement report.

4. The user equipment according to claim 3, in, The RRC message also includes integrity protection information; and Wherein, when the instruction is executed by the at least one processor, the user equipment causes at least: The integrity of the RRC message is verified using the integrity protection information; and The measurement is performed only if the integrity of the RRC message is successfully verified, based on the decrypted measurement configuration information.

5. A base station, comprising: At least one processor; as well as At least one memory storing instructions that, when executed by the at least one processor, cause the base station to at least: Perform the RRC setup procedure for the user equipment; as well as After the RRC setup procedure has been successfully completed, an RRC message is sent to the user equipment. The RRC message includes security information and encrypted measurement configuration information. The security information is the information required by the user equipment to decrypt the encrypted measurement configuration information. The measurement configuration information indicates the measurement to be performed by the user equipment.

6. The base station according to claim 5, wherein, The RRC message is an RRC security mode command message that includes the security information, and the RRC security mode command message carries the encrypted measurement configuration information.

7. The base station according to claim 5 or 6, wherein, When the instruction is executed by the at least one processor, the base station causes at least: The user equipment receives a response to the RRC message, the response including a measurement report indicating the result of a measurement performed by the user equipment.

8. The base station according to claim 7, wherein, The response is an RRC security mode completion message carrying the measurement report.

9. A method performed by a user equipment, the method comprising: Perform the Radio Resource Control (RRC) setup procedure with the base station; as well as After the RRC setup procedure has been successfully completed, an RRC message is received from the base station. The RRC message includes security information and encrypted measurement configuration information. The security information is the information required by the user equipment to decrypt the encrypted measurement configuration information. The measurement configuration information indicates the measurement to be performed by the user equipment.

10. A method performed by a base station, the method comprising: Perform the RRC setup procedure for the user equipment; as well as After the RRC setup procedure has been successfully completed, an RRC message is sent to the user equipment. The RRC message includes security information and encrypted measurement configuration information. The security information is the information required by the user equipment to decrypt the encrypted measurement configuration information. The measurement configuration information indicates the measurement to be performed by the user equipment.

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