Re-anchoring with SMF reselection

Abstract

Re-anchoring with session management function (SMF) reselection is disclosed herein. According to some embodiments, for an existing user equipment (UE) packet data unit (PDU) session, if the SMF determines that the current PDU session anchor (PSA) for the UE PDU session is to be relocated and further determines that the relocation involves SMF reselection, the SMF initiates re-establishment of the PDU session. During the re-establishment, the SMF conveys edge computing (EC) context information related to the new PDU session to an access and mobility management function (AMF). In some embodiments, the AMF can use some of the information related to the location (DNAI) of the PSA in the information to select a new SMF and pass the information to the selected SMF for the new PDU session. In some embodiments, based on the received information, the new SMF establishes a new PDU session and selects and configures the PSA(s) for the new session.

Description

[0001] Related applications

[0002] This application claims the benefit of provisional patent application serial number 63 / 064,223, filed on August 11, 2020, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0003] This disclosure relates to connectivity for edge computing (EC) in cellular communication networks. Background Technology

[0004] This disclosure relates to functionality supporting edge computing (EC) within the 3rd Generation Partnership Project (3GPP). The fifth-generation (5G) network architecture is defined by 3GPP Technical Specification (TS) 23.501. The roles of the network functions are defined as follows:

[0005] ● The Session Management Function (SMF) is responsible for session establishment, modification, and publication (including the selection and control of User Planning Function (UPF) entities); maintaining the topology of the Packet Data Unit (PDU) Session Anchor (PSA) UPF involved; and establishing and releasing tunnels between the Access Network (AN) and the UPF, as well as between UPFs. The SMF also configures traffic forwarding at the UPF. The SMF interacts with the UPF over the N4 reference point using the Packet Forwarding Control Protocol (PFCP) procedure.

[0006] ● The User Plane Function (UPF) handles user data traffic. Among other functions, the UPF provides an external PDU session interconnection point (e.g., PSA) to the data network (DN) and performs packet routing and forwarding (e.g., by supporting uplink classifiers (UL CL) to route traffic flows to instances of the DN, and / or supporting branch points to support multi-homed PDU sessions).

[0007] ● The Policy Control Function (PCF) supports a unified policy framework for managing network behavior. Specifically, the PCF provides Policy and Charging Control (PCC) rules to the Policy and Charging Enforcement Function (PCEF) (i.e., the SMF / UPF that executes policy and charging decisions based on the provided PCC rules).

[0008] ● Network Open Function (NEF) supports various functions, and specifically, in the context of this disclosure, NEF acts as an entry point to the operator's network, enabling external application functions (AFs) (such as content providers) to interact with the 3GPP core network through NEF.

[0009] ● The AF sends requests to influence the SMF routing decisions for traffic constituting a PDU session. AF requests can influence UPF selection or reselection and can allow user traffic to be routed via local access to a DN (e.g., identified by a Data Network Access Identifier or DNAI). The AF can communicate directly with the PCF in a Service-Based Architecture (SBA) domain or indirectly through the NEF (i.e., using the NEF's Application Programming Interface (API), which transmits AF communications to the PCF).

[0010] As described in Section 5.13 of 3GPP TS 23.501, EC enables operator and third-party services to be hosted close to the attached User Equipment (UE) access point to achieve efficient service delivery through reduced end-to-end latency and load on the transport network. The 5G core network selects the UPF close to the UE and performs traffic routing from the UPF to the local DN via the N6 interface. Section 5.13 of TS 23.501 also defines several enablers that support EC individually or in combination, including:

[0011] ● User Plane Selection or Reselection: As described in Section 6.3.3 of TS 23.501, the 5G core network selects or reselects the UPF to route user traffic to the local DN; and

[0012] ● Local routing and traffic control: The 5G core network selects traffic to be routed to applications in the local DN, as described in Section 5.6.4 of TS 23.501. This may include using a single PDU session with multiple PDU session anchors (UL CL / IPv6 multihoming).

[0013] Section 4.3.5 of TS 23.502 describes detailed functionality for providing session continuity, service continuity, and UP path management for the above use cases.

[0014] At least three connectivity models have been identified as being relevant to edge computing. They are documented in Section 4.2 of 3GPP Technical Report (TR) 23.748, and as... Figure 1 As shown. From Figure 1 It can be seen that these connectivity models include the following:

[0015] ● Distributed anchoring: The PDU session anchor (PSA) is moved to a remote local site within the network. The PDU session traffic remains the same for all users. Re-anchoring (i.e., PDU Session and Service Continuity (SSC) modes #2 and #3) is used to optimize traffic routing for all applications during long-distance movement.

[0016] ● Session Breakthrough: A PDU session has a PSA at the central site and a PDU session anchor at the local site. Only one of them provides an IP anchor. EC application traffic is selectively transferred to the local PDU session anchor using a UL classifier or multi-homing BP technology. When a user moves, the local PDU session anchor is re-anchored to optimize traffic routing for locally transferred traffic.

[0017] ● Multiple PDU sessions: EC applications use specific PDU sessions and PDU session anchors at the local site. Other applications use PDU sessions with a central PDU session anchor. The mapping between applications and PDU sessions is controlled by UE Routing Policy (URSP) rules. Re-anchoring (i.e., PDU session modes SSC#2 and SSC#3) is used to optimize traffic routing for EC applications when users move.

[0018] TR 23.748 proposes different solutions for EAS discovery and selection for the three connectivity models mentioned above. Furthermore, different methods for handling seamless EAS relocation are also proposed. These methods could imply UP path management solutions in 5GC for some existing PDU sessions, such as changing existing PSAs or adding new PSAs. Summary of the Invention

[0019] This document discloses a method and apparatus for performing re-anchoring using Session Management Function (SMF) reselection. This document discloses embodiments of a method for performing re-anchoring using SMF reselection in the core network of a cellular communication system. In some embodiments, the method includes determining at a first SMF that the current PDU session anchor (PSA) for a User Equipment (UE) Protocol Data Unit (PDU) session will be relocated, and that the relocation requires SMF reselection. The method also includes initiating a re-establishment of the UE PDU session, wherein initiation includes communicating Edge Computing (EC) dynamic context information related to the new UE PDU session to the Access and Mobility Management Function (AMF). The method also includes receiving EC dynamic context information from the first SMF at the AMF. The method further includes selecting a second SMF based on the EC dynamic context information. The method also includes sending the EC dynamic context information to the second SMF. The method further includes receiving EC dynamic context information from the AMF at the second SMF. The method also includes establishing a new UE PDU session based on the EC dynamic context information, wherein establishing a new UE PDU session includes selecting a PSA for the new UE-PDU session and configuring the PSA for the new UE-PDU session. Some embodiments may specify that the EC dynamic context information includes one or more of the following: one or more Data Network Access Identifiers (DNAIs) for a corresponding one or more PSAs; one or more traffic filters; N6 routing information; Domain Name System (DNS) configuration information;

[0020] Subscribed application features (AF) information; or related local policies.

[0021] This document also discloses an embodiment of a method for performing re-anchoring by utilizing SMF reselection in the first SMF of the core network of a cellular communication system.

[0022] In some embodiments, the method includes determining the current PSA for the UE PDU session.

[0023] The UE will be relocated, and the relocation requires the SMF to be reselected. The method also includes initiating the re-establishment of the UE PDU session, wherein initiation includes communicating the EC dynamic context information related to the new UE PDU session to the AMF.

[0024] This document also discloses an embodiment of a network node for implementing a first SMF in a core network for a cellular communication system, wherein the first SMF supports re-anchoring using SMF reselection. In some embodiments, the network node is adapted to determine that the current PSA for a UE PDU session will be relocated, and that the relocation requires SMF reselection. The network is also adapted to initiate the re-establishment of a UE PDU session, wherein initiation includes communicating EC dynamic context information related to the new UE PDU session to the AMF.

[0025] This document also discloses an embodiment of a network node for implementing a first SMF in the core network of a cellular communication system, wherein the SMF supports re-anchoring using SMF reselection. In some embodiments, the network node includes a network interface and processing circuitry associated with the network interface. The processing circuitry is configured to determine that the current PSA for a UE PDU session will be relocated, and that the relocation requires SMF reselection. The processing circuitry is also configured to initiate the re-establishment of the UE PDU session, wherein initiation includes communicating EC dynamic context information related to the new UE PDU session to the AMF.

[0026] This document also discloses embodiments of a method for performing re-anchoring in an AMF (Active Context Filter) within the core network of a cellular communication system to utilize an SMF (Small Context Filter) for reselection. In some embodiments, the method includes receiving EC (Electronic Dynamic Context) information from a first SMF. The method further includes selecting a second SMF based on the EC dynamic context information. The method also includes sending the EC dynamic context information to the second SMF. Some embodiments may provide that selecting a second SMF based on the EC dynamic context information includes: determining that the EC dynamic context message includes an indication to use a DNAI (Dual Identity Filter) for a new UE PDU session, and using the DNAI when selecting the second SMF.

[0027] This document also discloses embodiments of network nodes for implementing an AMF (Advanced Feature Filter) for a core network of a cellular communication system, wherein the AMF supports re-anchoring using an SMF (Small Subsystem Filter) reselection. In some embodiments, the network node is adapted to switch from a first SMF.

[0028] The network node receives EC dynamic context information. The network node is also adapted to select a second SMF based on the EC dynamic context information. The network node is further adapted to send EC dynamic context information to the second SMF. Some embodiments may provide that the network node is additionally adapted to perform any methods belonging to the network node described above.

[0029] This document also discloses embodiments of network nodes for implementing an AMF (Active Context Function) for a core network of a cellular communication system, wherein the AMF supports re-anchoring using Session Management Function (SMF) reselection. In some embodiments, the network node includes a network interface and processing circuitry associated with the network interface. The processing circuitry is configured to receive EC (Electronic Dynamic Context) information from a first SMF. The processing circuitry is also configured to select a second SMF based on the EC dynamic context information. The processing circuitry is further configured to send EC dynamic context information to the second SMF. Some embodiments may provide that the processing circuitry is also configured to perform any methods belonging to the aforementioned network node.

[0030] This document also discloses embodiments of a method for performing re-anchoring using SMF reselection in a second SMF within the core network of a cellular communication system. In some embodiments, the method includes receiving EC dynamic context information from the AMF. The method also includes establishing a new UE PDU session based on the EC dynamic context information. Some embodiments may provide establishing a new UE PDU based on EC dynamic context information.

[0031] The session includes: selecting the PSA for the new UE PDU session, and configuring the PSA for the new UE PDU session.

[0032] This document also discloses embodiments of a network node for implementing a second SMF for a core network of a cellular communication system, wherein the second SMF supports re-anchoring using SMF reselection. In some embodiments, the network node is adapted to receive EC dynamic context information from an AMF. The network node is also adapted to establish a new UE PDU session based on the EC dynamic context information. Some embodiments may provide that the network node is also adapted to perform any methods belonging to the aforementioned network node.

[0033] This document also discloses embodiments of a network node for implementing a second SMF (Secondary Message Facilitation) for a core network of a cellular communication system, wherein the SMF supports re-anchoring using SMF reselection. In some embodiments, the network node includes a network interface and processing circuitry associated with the network interface. The processing circuitry is configured to receive EC (Electronic Context Information) from the AMF (Active Context Facilitation). The processing circuitry is also configured to establish a new UE PDU session based on the EC dynamic context information. Some embodiments may provide that the processing circuitry is also configured to perform any methods belonging to the aforementioned network node. In some embodiments, the EC dynamic context information includes one or more of the following: one or more DNAIs for a corresponding one or more PDU session anchors (PSAs); one or more traffic filters; N6 routing information; DNS configuration information; subscribed AF information; and associated local policies. Attached Figure Description

[0034] The accompanying drawings, which are included in and form part of this specification, illustrate several aspects of this disclosure and, together with the specification, serve to explain the principles of this disclosure.

[0035] Figure 1 Three connectivity models related to edge computing (EC) are shown, which are copied from Section 4.2 of 3GPP Technical Report (TR) 23.748;

[0036] Figure 2 An example of a cellular communication system according to some embodiments of the present disclosure is shown;

[0037] Figure 3 and Figure 4 It shows Figure 3 The cellular communication system is an example implementation of the fifth-generation (5G) system (5GS);

[0038] Figure 5 An exemplary communication flow is shown for a process of re-anchoring using Session Management Function (SMF) reselection, according to some embodiments disclosed herein;

[0039] Figure 6 An exemplary communication flow is shown for a process of re-anchoring at edge application discovery using changes to the SMF, according to some embodiments disclosed herein; the process of re-anchoring at edge application discovery using changes to the SMF;

[0040] Figure 7 This is a schematic block diagram of a radio access node according to some embodiments of the present disclosure;

[0041] Figure 8 This illustrates some embodiments according to the present disclosure. Figure 7A schematic block diagram of a virtualization embodiment of a radio access node; and

[0042] Figure 9 It is based on some other embodiments of this disclosure Figure 7 A schematic block diagram of a radio access node. Detailed Implementation

[0043] The embodiments described below illustrate information that enables those skilled in the art to practice the embodiments and explain the best mode for practicing the embodiments. Upon reading the following description with reference to the accompanying drawings, those skilled in the art will understand the concepts of this disclosure and recognize the application of these concepts not specifically addressed herein. It should be understood that these concepts and applications fall within the scope of this disclosure.

[0044] Current approaches present several specific challenges. Currently, the information required for Packet Data Unit (PDU) Session Anchor (PSA) changes or the addition of new PSAs is pre-configured in the Session Management Function (SMF) or received by the SMF from the Policy Control Function (PCF) via Policy and Charging Control (PCC) rules. These PCC rules are communicated to the SMF when a PDU session is established or during a PDU session (e.g., based on triggers from an Application Function (AF), and they include a Data Network Access Identifier (DNAI) indication. The SMF has a local configuration for the DNAI indication that maps the DNAI to the PSA location. Furthermore, the SMF may receive other information related to the configuration required for new PSAs, such as traffic filters, N6 traffic handling rules, etc.

[0045] However, there are situations where the same SMF may not be able to handle the required PSA changes, such as the following:

[0046] ●DNAI triggered by Domain Name System (DNS) or requested by AF is supported using PDU session breach. At the mobility level, the new user equipment (UE) location is outside the SMF service area. The PDU session is SSC#2 or SSC#3.

[0047] ● DNS-triggered or AF-requested DNAI is being supported using distributed anchoring (i.e., the session is re-anchored to the edge to fulfill the request). At mobility, the new UE location is outside the SMF service area. The PDU session is SSC#2 or SSC#3.

[0048] ●DNAI triggered by DNS or requested by AF will be supported by utilizing distributed anchors through re-anchoring at the edge. The PDU session is SSC#2.

[0049] ● If the DNS query related to the fully qualified domain name (FQDN) of the edge computing (EC) application can be selected in the SMF that triggers the edge PSA when the SMF does not control any local PSA, or if the AF request is not controlled by the SMF's DNAI (e.g., because it represents a "campus" with its own SMF (see KI#5 in TR 23.748), for PDU session modes SSC#2 or SSC#3, where re-anchoring to the edge using a reassigned SMF is an option.

[0050] In these re-anchoring scenarios utilizing SMF reselection, the Access and Mobility Management Function (AMF) needs to select a new SMF capable of controlling the UPF, which utilizes N6 access to the DN at the requested location to support (multiple) PSAs. In some cases, such as the aforementioned "campus" scenario, the AMF may not have sufficient information to select the correct SMF. Furthermore, the new SMF needs all the information required to instruct the UPF and set up (multiple) new PSAs at the requested location based on the information in the trigger / request. However, the re-anchoring process currently does not convey the information necessary to guarantee these requirements.

[0051] Therefore, specific aspects and embodiments thereof in this disclosure can provide solutions to the above or other challenges. Various embodiments for solving one or more problems disclosed herein are presented. In particular, methods and apparatus for re-anchoring using SMF reselection are disclosed. According to some embodiments, if for existing UEs...

[0052] In a PDU session, if the SMF decides to relocate the current PSA used for the UE PDU session, and this involves SMF reselection, it initiates a PDU session re-establishment. During this re-establishment, it communicates contextual information related to the new PDU session to the AMF EC. The AMF can use some information related to the location of the PSA (DNAI) to select a new SMF and passes this information to the SMF selected for the new PDU session. Based on the received information, the new SMF establishes a new PDU session and selects and configures (multiple) PSAs for the new session.

[0053] Specific embodiments may provide one or more of the following technical advantages. The embodiments disclosed herein also allow for the repositioning of (multiple) PSAs when a new SMF is selected for a new session. In this way, the embodiments disclosed herein extend the applicability of different EC-related EAS selection and reselection use cases and provide alternative solutions for other use cases (e.g., campus scenarios). The embodiments disclosed herein may also be useful in other non-EC-related scenarios where it is not necessary to change or add PSAs to optimize PSA placement, but rather for other reasons (e.g., when UE IPv4 reconfiguration is required, SSC mode 2 re-anchoring and SMF reselection are necessary).

[0054] Before discussing in more detail the methods and apparatus for re-anchoring using SMF reselection, exemplary cellular communication systems in which some embodiments of this disclosure may be implemented are first discussed. In this regard, the following terms are defined:

[0055] Radio node: As used in this article, a “radio node” is a radio access node or wireless communication device.

[0056] Radio Access Node: As used herein, “radio access node” or “radio network node” or “radio access network node” is any node in the radio access network (RAN) of a cellular communication network used for wireless transmission and / or...

[0057] Or receive signals. Some examples of radio access nodes include, but are not limited to, base stations (e.g., new radio (NR) base stations (gNBs) in 3GPP 5G NR networks or enhanced or evolved Node Bs (eNBs) in 3GPP LTE networks), high-power or macro base stations, low-power base stations (e.g., micro base stations, pico base stations, home eNBs, etc.), relay nodes, network nodes that implement part of the functions of base stations (e.g., network nodes that implement gNB central unit (gNB-CU) or gNB distributed unit (gNB-DU)), or network nodes that implement part of the functions of certain other types of radio access nodes.

[0058] Core Network Node: As used herein, a "core network node" is any type of node in the core network or any node that implements core network functions. Some examples of core network nodes include, for example, a Mobility Management Entity (MME), a Packet Data Network Gateway (P-GW), a Service Capability Opening Function (SCEF), a Home Subscriber Server (HSS), etc. Other examples of core network nodes include those implementing Access and Mobility Management Functions (AMF), User Plane Functions (UPF), Session Management Functions (SMF), Authentication Server Functions (AUSF), and Network Slice Selection Functions.

[0059] Nodes for Network Functions (NSSF), Network Open Functions (NEF), Network Functions (NF) Repository Functions (NRF), Policy Control Functions (PCF), Routing Management Functions (MMF), and Unified Data Management (UDM), etc.

[0060] Communication equipment: As used herein, “communication equipment” is any type of device capable of accessing a network. Some examples of communication equipment include, but are not limited to: mobile phones, smartphones, sensor devices, instruments, vehicles, home appliances, medical devices, media players, cameras, or any type of consumer electronic device, such as, but not limited to, televisions, radios, lighting fixtures, tablets, laptops, or personal computers (PCs). Communication equipment can be portable, handheld, computer-based, or vehicle-mounted mobile devices capable of communicating voice and / or data via wireless or wired connections.

[0061] Wireless communication equipment: One type of communication equipment is a wireless communication device, which can be any type of wireless device that accesses a wireless network (e.g., a cellular network) (i.e., is served by a wireless network). Some examples of wireless communication devices include, but are not limited to: User Equipment (UE) devices in 3GPP networks, machine-type communication devices...

[0062] (MTC) devices and Internet of Things (IoT) devices. Such wireless communication devices can be, or can be integrated into, mobile phones, smartphones, sensor devices, meters, vehicles, home appliances, medical devices, media players, cameras, or any type of consumer electronic device, such as, but not limited to, televisions, radios, lighting equipment, tablets, laptops, or PCs. Wireless communication devices can be portable, handheld, computer-based, or in-vehicle mobile devices capable of communicating voice and / or data via wireless connectivity.

[0063] Network node: As used in this document, a “network node” is any node that is part of the RAN or core network of a cellular communication network / system.

[0064] Note that the descriptions presented herein focus on 3GPP cellular communication systems; therefore, 3GPP terminology or similar terms are frequently used. However, the concepts disclosed herein are not limited to 3GPP systems.

[0065] Note that the term “cell” may be referenced in the description herein; however, in particular with respect to the 5G NR concept, the term “beam” may be used instead of “cell”. Therefore, it is important to note that the concepts described herein apply equally to both “cell” and “beam”.

[0066] Figure 2An example of a cellular communication system 200 that can implement embodiments of the present disclosure is shown. In the embodiments described herein, the cellular communication system 200 is a 5G system (5GS) including a next-generation RAN (NG-RAN) and a 5G core (5GC) or an evolved packet system (EPS) including an evolved universal terrestrial RAN (E-UTRAN) and an evolved packet core (EPC). In this example, the RAN includes base stations 202-1 and 202-2. In the 5GS, base stations 202-1 and 202-2 include NR base stations (gNB) and optional next-generation eNBs (ng-eNBs) (e.g., LTE RAN nodes connected to the 5GC). In the EPS, the base stations include eNBs that control corresponding (macro)cells 204-1 and 204-2. Base stations 202-1 and 202-2 are generally referred to herein collectively as base station 202, and individually as base station 202. Similarly, (macro)cells 204-1 and 204-2 are generally referred to as (macro)cell 204 in this document, and are also referred to as (macro)cell 204 individually. The RAN may also include multiple low-power nodes 206-1 to 206-4 that control the corresponding small cells 208-1 to 208-4. Low-power nodes 206-1 to 206-4 may be small base stations (e.g., pico or femtocells) or remote radio heads (RRHs), etc.

[0067] It is worth noting that, although not shown, one or more of small cells 208-1 to 208-4 can be alternatively provided by base station 202. Low-power nodes 206-1 to 206-

[0068] 4 are generally referred to herein as low-power node 206, and are referred to individually as low-power node 206. Similarly, small cells 208-1 to 208-4 are generally referred to herein as small cell 208, and are referred to individually as small cell 208. Cellular communication system 200 also includes core network 210, which is referred to as 5GC in 5G system (5GS). Base station 202 (and optional low-power node 206) are connected to core network 210.

[0069] Base station 202 and low-power node 206 provide services to wireless communication devices 212-1 to 212-5 in corresponding cells 204 and 208. Wireless communication devices 212-1 to 212-

[0070] 5. This device is generally referred to herein as wireless communication device 212, and is referred to solely as wireless communication device 212. In the following description, wireless communication device 212 is generally a UE, but this disclosure is not limited thereto.

[0071] Figure 3A wireless communication system is shown, which is represented as a 5G network architecture consisting of core network functions (NFs), where the interaction between any two NFs is represented by a point-to-point reference point / interface. Figure 3 Can be regarded as Figure 2 A specific implementation of System 200.

[0072] From the access side, Figure 3 The 5G network architecture shown includes connections to the RAN.

[0073] RAN 202 or RAN 300 includes multiple UEs 212. Typically, RAN 202 includes base stations, such as eNBs or gNBs, or similar. From the core network side, Figure 3 The 5GC NF shown includes NSSF 302, AUSF 304,

[0074] UDM 306, AMF 300, SMF 308, PCF 310 and Application Function (AF) 312.

[0075] The reference point for the 5G network architecture is used to develop detailed call flows in the standardization process. The N1 reference point is defined as carrying signaling between UE 212 and AMF 300.

[0076] Reference points used to connect AN 202 and AMF 300, and AN 202 and UPF 314, are defined as N2 and N3, respectively. Reference point N11 exists between AMF 300 and SMF 308, meaning that SMF 308 is at least partially controlled by AMF 300. N4 is used by SMF 308 and UPF 314, allowing UPF 314 to be set using control signals generated by SMF 308, and enabling UPF 314 to report its status to SMF 308. N9 is a reference point for connections between different UPF 314s, and N14 is a reference point for connections between different AMF 300s. N15 and N7 are defined because PCF 310 applies policies to AMF 300 and SMF 308 respectively.

[0077] AMF 300 requires N12 to perform authentication for UE 212. N8 and N10 are defined because AMF 300 and SMF 308 require subscription data from UE 212.

[0078] The 5GC network aims to separate the user plane (UP) from the control plane (CP). The UP carries user traffic, while the CP carries network signaling. Figure 3In this architecture, the UPF 314 resides in the UP (Upplane), while all other NFs (i.e., AMF 300, SMF 308, PCF 310, AF312, NSSF 302, AUSF 304, and UDM 306) reside in the CP (Clipping Module). Separating the UP from the CP ensures that each plane resource is scaled independently. It also allows the UPF to be deployed separately from the CP functionality in a distributed manner. In this architecture, for applications requiring low latency, the UPF can be deployed very close to the UE to reduce the round-trip time (RTT) between the UE and the data network.

[0079] The core 5G network architecture consists of modular functions. For example, AMF 300 and SMF 308 are independent functions within the core component (CP). The separate AMF 300 and SMF 308 allow for independent evolution and scaling. Figure 3 As shown, other CP functions (such as PCF 310 and AUSF 304) can be separated. The modular functional design enables the 5GC network to flexibly support a variety of services.

[0080] Each NF interacts directly with another NF. Intermediate functions can be used to route messages from one NF to another. In CP, a set of interactions between two NFs is defined as a service, making reuse possible. This service supports modularity. UP supports interactions such as forwarding operations between different UPFs.

[0081] Figure 4 This illustrates a 5G network architecture that uses service-based interfaces between NFs in a CP, rather than... Figure 3 The point-to-point reference point / interface used in the 5G network architecture. However, the above reference... Figure 3 The NF described corresponds to Figure 4 The NF shown. Services provided by an NF to other authorized NFs can be exposed to the authorized NFs through service-based interfaces. Figure 4 In this context, service-based interfaces are represented by the letter "N", followed by the name of the NF. For example, Namf is the service-based interface for AMF 300, Nsmf is the service-based interface for SMF 308, and so on. Figure 4 The NEF 400 and NRF 402 mentioned above are not discussed above. Figure 3 As shown in the image. However, it needs to be clarified that... Figure 3 All NFs shown can be used with [other components] as needed. Figure 4 The NEF400 and NRF 402 interact, although Figure 3 There was no explicit statement from China.

[0082] Figure 3 and Figure 4Some properties of the NF shown can be described as follows: AMF 300 provides UE-based authentication, authorization, mobility management, etc. Since AMF 300 is independent of the access technology, even UE 212 using multiple access technologies is essentially connected to a single AMF 300. SMF 308 is responsible for session management and assigns Internet Protocol (IP) addresses to the UE. It also selects and controls UPF 314 for data transmission. If UE 212 has multiple sessions, a different SMF 308 can be assigned to each session to manage them individually, and different functions can be provided for each session. AF 312 provides information about packet flows to PCF 310, which is responsible for policy control, to support QoS. Based on this information, PCF 310 determines policies regarding mobility and session management to ensure the correct operation of AMF 300 and SMF 308. AUSF 304 supports authentication functions for the UE or similar and therefore stores data for UE or similar authentication, while UDM 306 stores UE 212's subscription data. The data network (DN) is not part of the 5GC network; the data network provides internet access or carrier services, etc.

[0083] NF can be implemented as a network element on dedicated hardware, a software instance running on dedicated hardware, or a virtualization function instantiated on a suitable platform (such as cloud infrastructure).

[0084] As mentioned above, in a re-anchoring scenario with SMF reselection,

[0085] The AMF needs to select a new SMF capable of controlling the UPF supporting (multiple) PSAs, which has N6 access to the DN at the requested location. However, in some cases, the AMF may not have sufficient information to select the correct SMF. Furthermore, the new SMF needs to have all the information required to instruct the UPF and establish (multiple) new PSAs at the requested location based on the information in the trigger / request. However, the processes involved in re-anchoring currently do not convey the information needed to guarantee the above requirements.

[0086] In this regard, methods and apparatus for re-anchoring using SMF reselection are disclosed. Figure 5 The general functionality of the process of re-anchoring using SMF reselection is shown. Figure 5The process illustrated assumes that the SMF includes local logic and may have additional configurations (e.g., local policies) to control the new functionality, including information provided to the AMF. As an example, these policies determine for each event whether the DNAI identifies a specific DN access or whether a generic identifier exists for the PSA closest to the UE's current location. Policies may also include an identifier for additional information that needs to be provided. This additional information is referred to herein as the "EC dynamic context." The SMF may also consider additional inputs related to the functionality received from the PCF (e.g., in the PCC for an application-specific AF request), such as the temporal and spatial validity of the AF request. The SMF may also consider any additional information, such as whether user application-related traffic has already affected the session (if any), and any application-specific additional configurations (if any) to determine how edge connectivity is handled based on the triggering event.

[0087] Figure 5 The process shown begins at step 500, where a PDU session is established. The UEPDU session is established and has one or more anchors (in a session breakup scenario). In a session breakup scenario, an insert can be introduced either at establishment or during session update (in this case, it is assumed that the same SMF can control the insert).

[0088] ● If the session break insertion may have been triggered by an AF request and a corresponding PCC update for the SMF, the process may include details such as the temporal and spatial validity of the SMF storage request, and these details will be taken into account when re-anchoring is disposed of in the future (e.g., whether the same DNAI should be kept at the mobility location).

[0089] ● If the session breach insertion may have been triggered by an application-specific DNS query or by a deep packet inspection (DPI) that detects application-specific traffic, the SMF stores and considers any process details that may relate to how the re-anchoring is handled in the future (e.g., the application-specific one that triggered the UL CL / local PSA insertion).

[0090] In step 501, SMF1 receives a trigger related to the UE PDU session.

[0091] In step 502, SMF1 determines the re-anchoring for the PDU session. This decision may be based on Service Level Agreement (SLA) information configured locally in the SMF, or on the PCC received from the PCF used for the PDU session. SMF1 determines whether to use SSC Mode 2 or SSC Mode 3 with SMF re-assignment.

[0092] In step 503, SMF1 initiates a change to the PDU session anchor using one of the following methods:

[0093] ● SSC Mode 3 with multiple PDU sessions (TS 23.502 Clause 4.3.5.2), with SMF relocation request, or

[0094] ● SSC Mode 2 with different PDU sessions (TS 23.502 Clause 4.3.5.1).

[0095] In step 504, in both cases, SMF1 may send an indication to AMF using the DNAI for the next PDU session (e.g., in the N1 SM information from AMF to UE via a call to the Namf_Communication_N1N2MessageTransfer message used for SSC mode #2 or SSC mode #3 session re-establishment). Local configuration plus any additional input specific to the relevant application (see step 500 and prerequisites) is used to determine the information provided. The provided DNAI may identify a specific DN access, but it may also be a generic identifier requesting the nearest PSA to the UE's current location. SMF1 may also send additional configuration information related to the new PDU session to AMF. The EC dynamic context that SMF1 may communicate to AMF may include the following:

[0096] ● (Multiple) local PSA DNAIs;

[0097] ● Traffic filter (for session breach scenarios);

[0098] ●N6 routing information;

[0099] ●DNS configuration (e.g., the DNS server used by the UE in a new PDU session);

[0100] ●Subscribed AF information (if PCF does not have this information); or

[0101] ●Relevant local strategies.

[0102] Note that some information can be determined again by the new SMF based on its local configuration or from the PCF. What needs to be provided as the EC dynamic context is information that depends on the old SMF-specific local configuration or information dynamically received / created by the SMF for the PDU session. Also note that SMF1 can send the EC dynamic context to the AMF by invoking the additional Nsmf_EventExposure service operation. In this case, the Namf_Communication_N1N2MessageTransfer message is still issued (but without the EC dynamic context) to trigger the (re)establishment of the session. The AMF stores the information received in this EC dynamic context because it needs to be considered when the UE sends a new PDU session establishment request to the same DN as instructed.

[0103] In step 505, when the AMF receives a UE PDU session establishment request for the same DN, the AMF considers whether it received an instruction from SMF1 in step 504 to use the "DNAI for the next PDU session" and selects a new SMF2 for the next PDU session establishment for the same UE request. If so, the AMF will use the received DNAI when selecting the new SMF (e.g., with the assistance of the NRF proposed in TR23.748 solution #50).

[0104] In step 506, the AMF communicates the received EC dynamic context information, including the received DNAI, to the newly selected SMF2 during the establishment of the next PDU session by the UE in Nsmf_PDUSession_CreateSMContextRequest.

[0105] In step 507, based on the information received from the AMF, SMF2 will select and set up (if necessary, ULCL / BP and (multiple) additional local PSAs) for the PDU session, and perform additional actions if necessary (e.g., setting the MNO DNS or the AF indicated by the notification for the PDU session). Note that usage reports for the relevant EC flow can be activated to track activity. If the EC application terminates, further re-anchoring (to the central UPF) can be triggered.

[0106] The above process begins with receiving a trigger associated with a specific APP to be launched within this UE PDU session. Several triggers are available (each implying a slightly different process), such as the following:

[0107] ● DNS queries from the UE. The new DNS component in the SMF involves DNS communication for UEs authorized for edge services (e.g., the SMF configures the necessary guidance in the UPF during session establishment). DNS queries for the FQDN applied to the EC are received by the SMF of the authorized UE / service (domain), and the SMF checks if PSA re-anchoring is required. If so, the SMF initiates the re-anchoring process. The following section combines... Figure 6 The corresponding functions are described.

[0108] ● The MNO uses a DPI engine (e.g., at the UPF) to differentiate application-specific traffic. Discovering a specific application for a specific user triggers a re-anchoring process involving a new SMF. This traffic differentiation can be based on DPI, such as based on Transport Layer Security (TLS) Client-Server Name Indication (SNI), based on a destination IP range published or provided by the application provider, etc.

[0109] ● The SMF receives traffic redirection requests from the AF for DNAIs that are not configured in the SMF (because it is outside the SMF service area, or because it represents a “campus” with its own SMF, see Key Issue #5 in Section 5.5 of TR 23.748).

[0110] ● The SMF receives a traffic redirection request for DNAI from the AF (e.g., to provide session continuity due to a planned EAS relocation, see Critical Issue #2 in TR 23.748). The SMF decides to re-anchor the session. Since the given PDU session does not support PSA changes using SSC Mode 3, the SMF determines that PSA changes using SSC Mode 2 are required.

[0111] ● As mentioned above, the SMF receives a traffic redirection request for the DNAI from the AF (to support service continuity during EAS relocation, related to critical issue #2 in TR 23.748). The requested DNAI is not configured in the SMF, therefore the SMF decides to perform an SSC mode 3 change to the PSA in the event of an SMF change. The new SMF will require information on how to configure the new local PSA (DNAI, traffic filter) for the application.

[0112] ●As mentioned above, however, the decision to re-anchor to another DNAI is based on SMF configuration or previous AF interaction and is triggered by UE mobility.

[0113] Figure 6 This demonstrates the process of re-anchoring at the edge application discovery point using changes to the SMF. The process shown is based on Solution #12 of TS23.728.

[0114] exist Figure 6 In step 600a, the SMF is pre-configured using SLA information (e.g., which EC application FQDN will trigger session re-anchoring).

[0115] In step 600b, a PDU session is established. The SMF instructs the UPF to forward DNS traffic to the SMF.

[0116] In step 601, the EC service is identified by the FQDN (AS-FFQDN). The application in the UE makes a DNS discovery request to discover the EAS. The DNS request is forwarded to SMF1 by the central PSA (UPF1).

[0117] In step 602, SMF1 checks whether the received FQDN is an AS-FQDN. If so, SMF1 buffers the DNS request. This decision can be based on SLA information configured locally in the SMF or on PCC received from the PCF used for the PDU session. SMF1 determines whether to use SSC mode 2 or SSC mode 3 with SMF relocation.

[0118] In step 603, SMF1 initiates a change to the PDU session anchor for SSC mode 2 or SSC mode 3 (as described in sections 4.3.5.1 and 4.3.5.2 of TS 23.205). Figure 5 As described in step 504, the SMF1 request includes the required EC-related information. Figure 5 As described in step 505 of the general procedure, when the AMF receives a UE PDU session establishment request for the same DN, the AMF will select SMF2 based on this information, and SMF2 will select UPF2 (i.e., the local PSA) for that PDU session. Furthermore, as... Figure 5 Step 506 of the general process is described.

[0119] AMF communicates information related to received ECs, including DNAIs received by the newly selected SMF2. Usage reports for the relevant EC streams are activated to track activity.

[0120] In step 604, SMF1 discards the DNS request.

[0121] In step 605, the UE sends a DNS query again (after the timer at the UE expires). The DNS query reaches the DNS resolver provided at the session establishment location of the new session via the local PSA and is resolved to the edge AS.

[0122] In step 606, the DNS response can be tuned to be as close as possible to the new PSA.

[0123] In step 607, the flow is applied and then begins toward the selected edge AS.

[0124] Figure 7 This is a schematic block diagram of a network node 700 according to some embodiments of the present disclosure. Optional functions are indicated by dashed boxes. For example, network node 700 may be a network node that implements all or part of the functionality of NF (e.g., SMF or PCF) or AF according to any embodiment described herein. As shown, network node 700 includes one or more processors 704 (e.g., central processing unit (CPU), application-specific integrated circuit).

[0125] (ASIC, Field Programmable Gate Array (FPGA), etc.), memory 706, and network interface 708. One or more processors 704 are also referred to herein as processing circuitry. One or more processors 704 operate to provide one or more functions of NF (e.g., SMF or AMF) or AF as described herein. In some embodiments, the functions(s) are implemented in software, for example, stored in memory 706 and executed by one or more processors 704.

[0126] Figure 8 This is a schematic block diagram illustrating a virtualized embodiment of a network node 700 according to some embodiments of the present disclosure. As used herein, a “virtualized” network node is an implementation of network node 700 in which at least a portion of the functionality of network node 700 is implemented as virtual components (e.g., via virtual machines executed on physical processing nodes in multiple networks). As shown, in this example, network node 700 includes one or more processing nodes 800 coupled to or included as part of networks 802. Each processing node 800 includes one or more processors 804 (e.g., CPU, ASIC, FPGA, etc.), memory 806, and network interface 808.

[0127] In this example, the functionality 810 of the network node 700 described herein (e.g., one or more functions of the NF (e.g., SMF or AMF) or AF described herein) is implemented at one or more processing nodes 800, or distributed across two or more processing nodes 800 in any desired manner. In some specific embodiments, some or all of the functionality 810 of the network node 700 described herein is implemented as virtual components executed by one or more virtual machines implemented in virtual environments hosted by the processing nodes 800.

[0128] In some embodiments, a node (e.g., processing node 800) is provided that enables at least one processor to perform the functions of network node 700 or implements one or more of the functions 810 of network node 700 in a virtual environment. In some embodiments, a carrier comprising the computer program product described above is provided. The carrier is one of electronic signals, optical signals, radio signals, or computer-readable storage media (e.g., a non-transient computer-readable medium such as a memory).

[0129] Figure 9This is a schematic block diagram of a network node 700 according to some other embodiments of the present disclosure. The network node 700 includes one or more modules 900, each implemented in software. The modules(s)900 provide the functionality of the network node 700 described herein (e.g., one or more of the functionality of the NF (e.g., SMF or AMF) or AF described herein). This discussion also applies to... Figure 8 The processing node 800, wherein the module 900 may be implemented at one of the processing nodes 800 or distributed across multiple processing nodes 800.

[0130] Any suitable steps, methods, features, functions, or benefits disclosed herein may be performed by one or more functional units or modules of one or more virtual devices. Each virtual device may include multiple such functional units. These functional units may be implemented by processing circuitry, which may include one or more microprocessors or microcontrollers, as well as other digital hardware, which may include digital signal processors (DSPs), application-specific digital logic, etc. The processing circuitry may be configured to execute program code stored in memory, which may include one or more types of memory, such as read-only memory (ROM), random access memory (RAM), cache memory, flash memory devices, optical storage devices, etc. The program code stored in memory includes program instructions for executing one or more telecommunications and / or data communication protocols and instructions for executing one or more techniques described herein. In some implementations, the processing circuitry may be used to cause corresponding functional units to perform corresponding functions according to one or more embodiments of this disclosure.

[0131] While the processes in the figures may illustrate a particular sequence of operations performed by a particular embodiment of this disclosure, it should be understood that such sequence is exemplary (e.g., alternative embodiments may perform operations in a different order, combine particular operations, overlap particular operations, etc.).

[0132] While not limited thereto, some exemplary embodiments of this disclosure are provided below.

[0133] Example 1: A method for performing re-anchoring in the core network of a cellular communication system using the System Management Function (SMF) reselection, the method comprising:

[0134] ●At the first SMF:

[0135] ○ It is determined that the current PDU session anchor PSA used for the User Equipment (UE) Protocol Data Unit (PDU) session will be relocated, and the relocation requires SMF reselection; and

[0136] ○ Initiate the re-establishment of the UE PDU session, which includes communicating the edge computing EC dynamic context information related to the new UE PDU session to the Access and Mobility Management Function (AMF);

[0137] ●At AMF:

[0138] ○ Receive EC dynamic context information from the first SMF;

[0139] ○ Selecting a second SMF based on EC dynamic context information; and

[0140] ○ Send EC dynamic context information to the second SMF; and

[0141] ●At the second SMF:

[0142] ○ Receive EC dynamic context information from AMF; and

[0143] ○ Establishing a new UE PDU session based on EC dynamic context information, which includes:

[0144] ■ Select the PSA for the new UE PDU session; and

[0145] ■ Configure PSA for new UE PDU sessions.

[0146] Example 2: According to the method of Example 1, the EC dynamic context information includes one or more of the following:

[0147] ●One or more Data Network Access Identifiers (DNAIs) for one or more corresponding PSAs;

[0148] ●One or more flow filters;

[0149] ●N6 routing information;

[0150] ●Domain Name System (DNS) configuration information;

[0151] ●Subscribed application function AF information; or

[0152] ●Relevant local strategies.

[0153] Example 3: A method for performing re-anchoring using SMF reselection in the first session management function (SMF) of a cellular communication system's core network, the method comprising:

[0154] ● It is determined that the current PDU session anchor PSA used for the User Equipment (UE) Protocol Data Unit (PDU) session will be relocated, and the relocation requires SMF reselection; and

[0155] ● Initiate the re-establishment of the UE PDU session, which includes communicating edge computing EC dynamic context information related to the new UE PDU session to the Access and Mobility Management Function (AMF).

[0156] Example 4: A first session management function (SMF) for a core network of a cellular communication system, wherein the first SMF supports re-anchoring using SMF reselection, and the first SMF is adapted to:

[0157] ● It is determined that the current PDU session anchor PSA used for the User Equipment (UE) Protocol Data Unit (PDU) session will be relocated, and the relocation requires SMF reselection; and

[0158] ● Initiate the re-establishment of the UE PDU session, which includes communicating edge computing EC dynamic context information related to the new UE PDU session to the Access and Mobility Management Function (AMF).

[0159] Example 5: A network node for implementing a first session management function (SMF) for a core network of a cellular communication system, wherein the first SMF supports re-anchoring using SMF reselection, the network node comprising:

[0160] ● Network interface; and

[0161] ● Processing circuitry associated with the network interface, the processing circuitry being adapted to enable the network node to implement a first SMF, such that the first SMF is configured as follows:

[0162] ○ It is determined that the current PDU session anchor PSA used for the User Equipment (UE) Protocol Data Unit (PDU) session will be relocated, and the relocation requires SMF reselection; and

[0163] ○ Initiate the re-establishment of the UE PDU session, which includes communicating the edge computing EC dynamic context information related to the new UE PDU session to the Access and Mobility Management Function (AMF).

[0164] Example 6: A method for performing re-anchoring using SMF reselection within the Access and Mobility Management Function (AMF) of a cellular communication system's core network, the method comprising:

[0165] ● Receive dynamic context information for the edge computing EC from the first session management function (SMF);

[0166] ● Selecting a second SMF based on EC dynamic context information; and

[0167] ● Send EC dynamic context information to the second SMF.

[0168] Example 7: According to the method of Example 6, the selection of the second SMF based on EC dynamic context information includes:

[0169] ● Determine the EC dynamic context information, including the indication of using the Data Network Access Identifier (DNAI) for the new UE PDU session; and

[0170] ● Use DNAI when selecting the second SMF.

[0171] Example 8: An Access and Mobility Management Function (AMF) for a core network of a cellular communication system, wherein the AMF supports re-anchoring using SMF reselection, and the AMF is suitable for:

[0172] ● Receive dynamic context information for the edge computing EC from the first session management function (SMF);

[0173] ● Selecting a second SMF based on EC dynamic context information; and

[0174] ● Send EC dynamic context information to the second SMF.

[0175] Example 9: According to the AMF of Example 8, wherein the AMF is adapted to select a second SMF based on EC dynamic context information in the following manner:

[0176] ● Determine the EC dynamic context information, including the indication of using the Data Network Access Identifier (DNAI) for the new UE PDU session; and

[0177] ● Use DNAI when selecting a second SMF.

[0178] Example 10: A network node for implementing Access and Mobility Management Functions (AMF) for a core network of a cellular communication system, wherein the AMF supports re-anchoring using SMF reselection, the network node comprising:

[0179] ● Network interface; and

[0180] ● Processing circuitry, associated with the network interface, is adapted to enable network nodes to implement AMF, such that AMF is configured as follows:

[0181] ○ Receive dynamic context information for the edge computing EC from the first session management function (SMF);

[0182] ○ Selecting a second SMF based on EC dynamic context information; and

[0183] ○ Send EC dynamic context information to the second SMF.

[0184] Example 11: According to the network node of Example 10, where AMF passes through

[0185] Configured to select the second SMF based on EC dynamic context information as follows:

[0186] ● Determine the EC dynamic context information, including the indication of using the Data Network Access Identifier (DNAI) for the new UE PDU session; and

[0187] ● Use DNAI when selecting the second SMF.

[0188] Example 12: A method for performing re-anchoring using SMF reselection in a second session management function (SMF) of a core network of a cellular communication system, the method comprising:

[0189] ● Receive dynamic context information for edge computing (EC) from the Access and Mobility Management Function (AMF); and

[0190] ● Establish a new User Equipment (UE) Protocol Data Unit (PDU) session based on EC dynamic context information.

[0191] Example 13: According to the method of Example 12, establishing a new UE PDU session based on EC dynamic context information includes:

[0192] ● Select the PDU session anchor PSA for the new UE PDU session; and

[0193] ● Configure PSA for new UE PDU sessions.

[0194] Example 14: A second session management function (SMF) for a core network of a cellular communication system, wherein the second SMF supports re-anchoring using SMF reselection, and the second SMF is suitable for:

[0195] ● Receive dynamic context information for edge computing (EC) from the Access and Mobility Management Function (AMF); and

[0196] ● Establish a new User Equipment (UE) Protocol Data Unit (PDU) session based on EC dynamic context information.

[0197] Example 15: According to the second SMF of Example 14, the second SMF is adapted to establish a new UE PDU session based on EC dynamic context information in the following manner:

[0198] ● Select the PDU session anchor PSA for the new UE PDU session; and

[0199] ● Configure PSA for new UE PDU sessions.

[0200] Example 16: A network node for implementing a second session management function (SMF) for a core network of a cellular communication system, wherein the second SMF supports re-anchoring using SMF reselection, the network node comprising:

[0201] ● Network interface; and

[0202] ● Processing circuitry, associated with the network interface, is adapted to enable the network node to implement a second SMF, such that the second SMF is configured as follows:

[0203] ○ Receive dynamic context information for edge computing (EC) from the Access and Mobility Management Function (AMF); and

[0204] ○ Establish a new User Equipment (UE) Protocol Data Unit (PDU) session based on EC dynamic context information.

[0205] Example 17: According to the network node of Example 16, the second SMF is configured to establish a new UEPDU session based on EC dynamic context information by being configured as follows:

[0206] ● Select the PDU session anchor PSA for the new UE PDU session; and

[0207] ● Configure PSA for new UE PDU sessions.

[0208] Example 18: The method according to any one of Examples 3, 6, 7, 12, and 13, wherein the EC dynamic context information includes one or more of the following:

[0209] ●One or more Data Network Access Identifiers (DNAIs) for one or more corresponding PSAs;

[0210] ●One or more flow filters;

[0211] ●N6 routing information;

[0212] ●Domain Name System (DNS) configuration information;

[0213] ●Subscribed application function AF information; or

[0214] ●Related local policies.

[0215] At least some of the following abbreviations may be used in this disclosure. In the event of any inconsistency between the abbreviations, the usage above shall prevail. If abbreviations are listed multiple times below, the first listing shall take precedence over any subsequent listing(s).

[0216] ●3GPP Third Generation Partner Program

[0217] ●5G (Fifth Generation)

[0218] ●5GC Fifth Generation Core

[0219] ●5GS Fifth Generation System

[0220] ●AF Application Functions

[0221] ●AMF Access and Mobility Functions

[0222] ●AN access network

[0223] ●AP Access Point

[0224] ●ASIC (Application-Specific Integrated Circuit)

[0225] ●AUSF Authentication Server Functions

[0226] ●CPU Central Processing Unit

[0227] ●DN Data Network

[0228] ●DSP Digital Signal Processor

[0229] ●eNB Enhanced or Evolved Node B

[0230] ●EPS Evolution Grouping System

[0231] ●E-UTRA Evolution of Universal Terrestrial Radio Access

[0232] ●FPGA Field Programmable Gate Array

[0233] ●gNB New Radio Base Station

[0234] ●gNB DU New Radio Base Station Distributed Unit

[0235] ●HSS Home Subscriber Server

[0236] ●IoT (Internet of Things)

[0237] ●IP Internet Protocol

[0238] ●LTE Long Term Evolution

[0239] ●MME (Mobility Management Entity)

[0240] ●MTC Machine Type Communication

[0241] ●NEF Network Open Functions

[0242] ●NF Network Functions

[0243] ●NR New Radio

[0244] ●NRF Network Function Repository Function

[0245] ●NSSF Network Slice Selection Function

[0246] ●OTT over-the-top transmission

[0247] ●PC Personal Computer

[0248] ●PCF Policy Control Function

[0249] ●P-GW Packet Data Network Gateway

[0250] ●QoS (Quality of Service)

[0251] ●RAM (Random Access Memory)

[0252] ●RAN Radio Access Network

[0253] ●ROM Read-Only Memory

[0254] ●RRH Remote Radio Head

[0255] ●RTT Round Trip Time

[0256] ●SCEF Service Capability Opening Functionality

[0257] ●SMF Session Management Function

[0258] ●UDM Unified Data Management

[0259] ●UE User Equipment

[0260] ●UPF User Plane Function

[0261] Those skilled in the art will recognize improvements and modifications to the embodiments of this disclosure. All such improvements and modifications are considered to be within the scope of the concepts disclosed herein.

Claims

1. A method for performing re-anchoring in the core network (210) of a cellular communication system (200) by utilizing a system management function (SMF) (308) for reselection, the method comprising: At the first SMF: Receive (501) a trigger related to a User Equipment (UE) Protocol Data Unit (PDU) session, wherein the trigger includes one of an Application Function (AF) request or a Domain Name System (DNS) query from the UE; In response to receiving the trigger, it is determined (502) based on the trigger that the current PDU session anchor PSA for the UE PDU session will be relocated, and the relocation requires the SMF to reselect, wherein determining based on the trigger includes determining that the new UE location is outside the service area of ​​the first SMF, the Data Network Access Identifier (DNAI) triggered by DNS or requested by AF will be supported using distributed anchors, the first SMF does not control any local PSA, or the AF requests a DNAI not controlled by the first SMF; as well as Initiate (503-504) the re-establishment of the UE PDU session, wherein initiation includes: communicating edge computing EC dynamic context information related to the new UE PDU session to the Access and Mobility Management Function (AMF) (300); At the AMF: Receive the EC dynamic context information (504) from the first SMF; Based on the EC dynamic context information, select (505) the second SMF; and Send the EC dynamic context information (506) to the second SMF; and At the second SMF: Receive (506) the EC dynamic context information from the AMF; and Establishing (507) the new UE PDU session based on the EC dynamic context information, wherein establishing the new UE PDU session includes: Select the PSA for the new UE PDU session; and Configure the PSA for the new UE PDU session; The EC dynamic context information mentioned above includes one or more of the following: One or more flow filters; N6 routing information; DNS configuration information; Subscribed AF information; or Relevant local policies.

2. A method for performing re-anchoring using SMF reselection in a first session management function (SMF) (308) in the core network (210) of a cellular communication system (200), the method comprising: Receive (501) a trigger related to a User Equipment (UE) Protocol Data Unit (PDU) session, wherein the trigger includes one of an Application Function (AF) request or a Domain Name System (DNS) query from the UE; In response to receiving the trigger, it is determined (502) based on the trigger that the current PDU session anchor PSA for the UE PDU session will be relocated, and the relocation requires the SMF to reselect, wherein determining based on the trigger includes determining that the new UE location is outside the service area of ​​the first SMF, the Data Network Access Identifier (DNAI) triggered by DNS or requested by AF will be supported using distributed anchors, the first SMF does not control any local PSA, or the AF requests a DNAI not controlled by the first SMF; as well as Initiate (503-504) the re-establishment of the UE PDU session, wherein initiation includes communicating edge computing EC dynamic context information related to the new UE PDU session to the Access and Mobility Management Function (AMF) (300); The EC dynamic context information mentioned above includes one or more of the following: One or more flow filters; N6 routing information; DNS configuration information; Subscribed AF information; or Relevant local policies.

3. A network node (700) for implementing a first session management function (SMF) (308) for a core network (210) of a cellular communication system (200), wherein the first SMF supports re-anchoring using SMF reselection, the network node being adapted to: Receive (501) a trigger related to a User Equipment (UE) Protocol Data Unit (PDU) session, wherein the trigger includes one of an Application Function (AF) request or a Domain Name System (DNS) query from the UE; In response to receiving the trigger, it is determined (502) based on the trigger that the current PDU session anchor PSA for the UE PDU session will be relocated, and the relocation requires the SMF to be reselected, wherein the network node is adapted to determine based on the trigger in such a way that: the new UE location is outside the service area of ​​the first SMF, the Data Network Access Identifier (DNAI) triggered by DNS or requested by AF will be supported using distributed anchors, the first SMF does not control any local PSA, or the AF requests a DNAI that is not controlled by the first SMF; as well as Initiate (503-504) the re-establishment of the UE PDU session, wherein initiation includes communicating edge computing EC dynamic context information related to the new UE PDU session to the Access and Mobility Management Function (AMF) (300); The EC dynamic context information mentioned above includes one or more of the following: One or more flow filters; N6 routing information; DNS configuration information; Subscribed AF information; or Relevant local policies.

4. A network node (700) for implementing a first session management function (SMF) (308) of a core network (210) of a cellular communication system (200), wherein the first SMF supports re-anchoring using SMF reselection, the network node comprising: Network interface (708); as well as Processing circuitry (704), associated with the network interface, is configured to: Receive (501) a trigger related to a User Equipment (UE) Protocol Data Unit (PDU) session, wherein the trigger includes one of an Application Function (AF) request or a Domain Name System (DNS) query from the UE; In response to receiving the trigger, it is determined (502) based on the trigger that the current PDU session anchor PSA for the UE PDU session will be relocated, and the relocation requires SMF reselection, wherein the processing circuit is configured to determine based on the trigger in such a way that: the new UE location is outside the service area of ​​the first SMF, the Data Network Access Identifier (DNAI) triggered by DNS or requested by AF will be supported using distributed anchors, the first SMF does not control any local PSA, or the AF request is for a DNAI not controlled by the first SMF; as well as Initiate (503-504) the re-establishment of the UE PDU session, wherein initiation includes: communicating edge computing EC dynamic context information related to the new UE PDU session to the Access and Mobility Management Function (AMF) (300); The EC dynamic context information mentioned above includes one or more of the following: One or more flow filters; N6 routing information; DNS configuration information; Subscribed AF information; or Relevant local policies.

5. A method for performing re-anchoring by utilizing session management function (SMF) (308) reselection in the core network (210) of a cellular communication system (200), the method comprising: Receive (504) edge-computed EC dynamic context information from the first SMF, wherein the EC dynamic context information includes at least one of the following: Information regarding the Data Network Access Identifier (DNAI) for a new User Equipment (UE) Protocol Data Unit (PDU) session; One or more flow filters; N6 routing information; Domain Name System (DNS) configuration information; Subscribed application features AF information; or Relevant local strategies; Selecting (505) a second SMF for the new UE PDU session for the UE based on the EC dynamic context information includes determining that the EC dynamic context information includes information about the DNAI for the new UE PDU session, and using the DNAI when selecting the second SMF; as well as Send the EC dynamic context information (506) to the second SMF.

6. A network node (700) for implementing Access and Mobility Management Function (AMF) (300) of a core network (210) of a cellular communication system (200), wherein the AMF supports re-anchoring using Session Management Function (SMF) (308) reselection, the network node being adapted to: Receive (504) edge-computed EC dynamic context information from the first SMF, wherein the EC dynamic context information includes at least one of the following: Information regarding the Data Network Access Identifier (DNAI) for a new User Equipment (UE) Protocol Data Unit (PDU) session; One or more flow filters; N6 routing information; Domain Name System (DNS) configuration information; Subscribed application features AF information; or Relevant local strategies; Selecting (505) a second SMF for the new UE PDU session based on the EC dynamic context information includes determining that the EC dynamic context information includes information about the DNAI for the new UE PDU session, and using the DNAI when selecting the second SMF; as well as Send the EC dynamic context information (506) to the second SMF.

7. The network node of claim 6, wherein the network node is further adapted to perform the method of claim 5.

8. A network node (700) for implementing Access and Mobility Management Function (AMF) (300) of a core network (210) of a cellular communication system (200), wherein the AMF supports re-anchoring using Session Management Function (SMF) (308) reselection, the network node comprising: Network interface (708); as well as Processing circuitry (704), associated with the network interface, is configured to: Receive (504) edge computing EC dynamic context information from the first SMF, the EC dynamic context information including at least one of the following: Information regarding the Data Network Access Identifier (DNAI) for a new User Equipment (UE) Protocol Data Unit (PDU) session; One or more flow filters; N6 routing information; Domain Name System (DNS) configuration information; Subscribed application features AF information; or Relevant local strategies; Selecting (505) a second SMF for the new UE PDU session for the UE based on the EC dynamic context information includes determining that the EC dynamic context information includes information about the DNAI for the new UE PDU session, and using the DNAI when selecting the second SMF; as well as Send the EC dynamic context information (506) to the second SMF.

9. The network node of claim 8, wherein the processing circuitry is further configured to perform the method of claim 5.

10. A method for performing re-anchoring using SMF reselection in a second session management function (SMF) (308) in the core network (210) of a cellular communication system (200), the method comprising: Receive (506) edge computing EC dynamic context information from the Access and Mobility Management Function (AMF) (300), the EC dynamic context information including at least one of the following: Information regarding the Data Network Access Identifier (DNAI) for a new User Equipment (UE) Protocol Data Unit (PDU) session; One or more flow filters; N6 routing information; Domain Name System (DNS) configuration information; Subscribed application features AF information; or Relevant local strategies; as well as Establishing (507) a new UE PDU session for the UE based on the EC dynamic context information, including selecting a PDU session anchor PSA for the new UE PDU session and configuring the PSA for the new UE PDU session.

11. A network node (700) for implementing a second session management function (SMF) (308) for a core network (210) of a cellular communication system (200), wherein the second SMF is capable of performing re-anchoring using SMF reselection, the network node being adapted to: Receive (506) edge computing EC dynamic context information from the Access and Mobility Management Function (AMF) (300), the EC dynamic context information including at least one of the following: Information regarding the Data Network Access Identifier (DNAI) for a new User Equipment (UE) Protocol Data Unit (PDU) session; One or more flow filters; N6 routing information; Domain Name System (DNS) configuration information; Subscribed application features AF information; or Relevant local strategies; as well as Establishing (507) a new UE PDU session for the UE based on the EC dynamic context information, including selecting a PDU session anchor PSA for the new UE PDU session and configuring the PSA for the new UE PDU session.

12. The network node of claim 11, wherein the network node is further adapted to perform the method of claim 10.

13. A network node (700) for implementing a second session management function (SMF) (308) for a core network (210) of a cellular communication system (200), wherein the second SMF supports re-anchoring using SMF reselection, the network node comprising: Network interface (708); as well as Processing circuitry (704), associated with the network interface, is configured to: Receive (506) edge computing EC dynamic context information from the Access and Mobility Management Function (AMF) (300), the EC dynamic context information including at least one of the following: Information regarding the Data Network Access Identifier (DNAI) for a new User Equipment (UE) Protocol Data Unit (PDU) session; One or more flow filters; N6 routing information; Domain Name System (DNS) configuration information; Subscribed application features AF information; or Relevant local strategies; as well as Establishing (507) a new UE PDU session for the UE based on the EC dynamic context information, including selecting a PDU session anchor PSA for the new UE PDU session and configuring the PSA for the new UE PDU session.

14. The network node of claim 13, wherein the processing circuitry is further configured to perform the method of claim 10.

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