KR20230140376A - Apparatus and method for providng n6-lan using service function chaining in wireless communication system - Google Patents

Abstract

This disclosure relates generally to wireless communication systems, and more specifically to an apparatus and method for providing N6-LAN services using SFC in a wireless communication system. A method for supporting the N6-LAN traffic steering function using SFC technology in a wireless communication system is the PCF (policy control function), which is an additional method for N6-LAN traffic steering based on PCC (policy and charging control) rules. A process of configuring information, a process of transmitting the configured additional information to a session management function (SMF), the SMF configuring a forwarding action rule (FAR) containing additional information for N6-LAN traffic steering, and the SMF may include a process of transmitting a FAR containing additional information to a user plane function (UPF), and the UPF may include a process of performing SFC encapsulation based on a predefined SFC policy and FAR.

Description

Apparatus and method for providing N6-LAN service using SFC in a wireless communication system {APPARATUS AND METHOD FOR PROVIDNG N6-LAN USING SERVICE FUNCTION CHAINING IN WIRELESS COMMUNICATION SYSTEM}

This disclosure relates to a wireless communication system, and more specifically, to an apparatus and method for providing an N6-LAN service using SFC in a wireless communication system.

In the 5G communication system, N6-LAN service is one of the interfaces used instead of Gi/SGi-LAN, which was mainly used in LTE, and mobile communication operators can provide various additional services through N6_LAN service.

SFC (Service Function Chaining) technology is one of the ways that mobile communication operators can provide various additional services through service function chaining. SFC technology performs functions such as DPI, NAT, firewall, policy control, and traffic/content optimization, and packets can be processed within the service function chain.

SFC may operate by extracting part of the packet, determining which SF (service function) to go through based on it, and then selecting the next SF. By chaining service functions using SFC, the network packet processing process can be simplified and various additional services can be provided.

This will allow mobile communication operators to provide more diverse and efficient services to their customers.

Based on the above-described discussion, this disclosure provides an apparatus and method for providing an N6-LAN service using SFC in a wireless communication system.

Additionally, the present disclosure provides an apparatus and method for managing information for performing SFC encapsulation in a wireless communication system.

Additionally, the present disclosure provides an apparatus and method for packet processing for SFC encapsulation in a wireless communication system.

Additionally, the present disclosure provides an apparatus and method for providing N6-LAN service using SFC technology in a wireless communication system.

Additionally, the present disclosure provides an apparatus and method for directly controlling the N6-LAN service for specific application traffic at the request of a service provider using SFC technology in a wireless communication system.

According to various embodiments of the present disclosure, a method for supporting an N6-LAN traffic steering function using SFC technology in a wireless communication system is based on a policy control function (PCF) based on policy and charging control (PCC) rules. A process of configuring additional information for N6-LAN traffic steering, a process of transmitting the configured additional information to a session management function (SMF), and the SMF sends a forwarding action (FAR) containing additional information for N6-LAN traffic steering. rule), the SMF transmits a FAR containing additional information to the user plane function (UPF), and the UPF performs SFC encapsulation based on the predefined SFC policy and FAR. You can.

According to various embodiments of the present disclosure, a device for supporting an N6-LAN traffic steering function using SFC technology in a wireless communication system includes a policy control function (PCF), a session management function (SMF), and a user plane function (UPF). ), the PCF configures additional information for N6-LAN traffic steering based on policy and charging control (PCC) rules, and transmits the configured additional information to a session management function (SMF), and SMF Configures a forwarding action rule (FAR) containing additional information for the N6-LAN traffic steering, SMF transmits the FAR including additional information to the user plane function (UPF), and UPF is a predefined SFC policy. SFC encapsulation can be performed based on and FAR.

According to various embodiments of the present disclosure, a method of operating a user plane function (UPF) in a wireless communication system includes policy and charging control (PCC) rules from a policy control function (PCF) via a session management function (SMF). Based on this, it will include a process of receiving additional information for N6-LAN traffic steering, and a process of performing SFC encapsulation based on a predefined SFC (service function chaining) policy and FAR (forwarding action rule). You can.

In a wireless communication system, a user plane function (UPF) includes a transceiver and a control unit operably connected to the transceiver, wherein the control unit transmits information from a policy control function (PCF) to a PCC via a session management function (SMF). Receives additional information for N6-LAN traffic steering based on (policy and charging control) rules, and SFC (service function chaining) based on predefined SFC (service function chaining) policy and FAR (forwarding action rule) Encapsulation can be performed.

Devices and methods according to various embodiments of the present disclosure provide N6-LAN services using SFC technology, thereby directly controlling N6-LAN services for specific application traffic at the request of service providers as well as mobile communication providers. make it possible

The effects that can be obtained from the present disclosure are not limited to the effects mentioned above, and other effects not mentioned can be clearly understood by those skilled in the art from the description below. will be.

1 illustrates an example of an S/Gi-LAN service function according to various embodiments of the present disclosure.
Figure 2 shows an example of configuring an N6-LAN according to various embodiments of the present disclosure.
Figure 3 shows a conceptual diagram of SFC according to various embodiments of the present disclosure.
FIG. 4 illustrates an example of a packet format for performing SFC encapsulation according to various embodiments of the present disclosure.
Figure 5 shows an example of a method for managing traffic steering policy information in 5GS, according to an embodiment of the present invention.
Figure 6 shows an example of a PCC rule that additionally defines traffic steering information necessary to provide an SFC service in a wireless system according to an embodiment of the present invention.
FIG. 7 illustrates an example of information requested for an SFC service by AF using a method of requesting AF influenced traffic routing, according to an embodiment of the present disclosure.
Figure 8 shows an example of traffic steering-related information in FAR transmitted from SMF to UPF, according to an embodiment of the present invention.
Figure 9 shows an example of a process in which UPF performs packet forwarding, according to various embodiments of the present disclosure.
Figure 10 shows an example of a procedure for managing traffic steering information requested by AF according to an embodiment of the present invention.
Figure 11 shows an example of a procedure for managing traffic steering information set within 5GS according to an embodiment of the present invention.
FIG. 12 illustrates the configuration of a network entity in a wireless communication system according to various embodiments of the present disclosure.
FIG. 13 illustrates the configuration of a device for supporting an N6-LAN traffic steering function using SFC technology in a wireless communication system according to various embodiments of the present disclosure.

Terms used in the present disclosure are merely used to describe specific embodiments and may not be intended to limit the scope of other embodiments. Singular expressions may include plural expressions, unless the context clearly indicates otherwise. Terms used herein, including technical or scientific terms, may have the same meaning as generally understood by a person of ordinary skill in the technical field described in this disclosure. Among the terms used in this disclosure, terms defined in general dictionaries may be interpreted to have the same or similar meaning as the meaning they have in the context of related technology, and unless clearly defined in this disclosure, have an ideal or excessively formal meaning. It is not interpreted as In some cases, even terms defined in the present disclosure cannot be interpreted to exclude embodiments of the present disclosure.

In various embodiments of the present disclosure described below, a hardware approach method is explained as an example. However, since various embodiments of the present disclosure include technology using both hardware and software, the various embodiments of the present disclosure do not exclude software-based approaches.

Hereinafter, the present disclosure relates to an apparatus and method for providing N6-LAN service using SFC in a wireless communication system. Specifically, the present disclosure provides technology for managing information for performing SFC encapsulation in a wireless communication system, technology for packet processing for SFC encapsulation, technology for providing N6-LAN service using SFC technology, and SFC technology. This explains a technology for directly controlling the N6-LAN service for specific application traffic at the request of the service provider.

In the following description, terms referring to signals, terms referring to channels, terms referring to control information, terms referring to network entities, terms referring to device components, etc. are used for convenience of explanation. This is exemplified. Accordingly, the present disclosure is not limited to the terms described below, and other terms having equivalent technical meaning may be used.

In addition, the present disclosure describes various embodiments using terms used in some communication standards (eg, 3rd Generation Partnership Project (3GPP)), but this is only an example for explanation. Various embodiments of the present disclosure can be easily modified and applied to other communication systems.

1 illustrates an example of an S/Gi-LAN service function according to various embodiments of the present disclosure.

Referring to FIG. 1, a 4G-based mobile core network may be composed of an evolved packet core (EPC) and Gi/SGi-LAN. Gi-LAN is a mobile communication service provider that uses Load Balancer (LB), AF (application filter), Firewall, Carrier-grade NAT (network address translation), DPI (deep packet inspection), Video Optimization (VO), and SBC (Session Border Control). ), policy control, and traffic/content optimization, etc. is a network that provides various additional services through a combination of IP-based service functions.

Specifically, LB is a device that provides functions that enable stable and fast service provision through server load distribution. AF is a device that provides the function of filtering or monitoring application data on a network. Firewall is a device that provides functions to protect networks and systems from illegal external access and attacks. Carrier-grade NAT is a device that provides address allocation and management functions using NAT to solve the problem of lack of IPv4 addresses. DPI is a device that provides the function of identifying specific protocols, services, applications, etc. by analyzing data inside packets. VO is a device that provides a function to efficiently use network bandwidth by optimizing the quality and bandwidth of video data. SBC is equipment that provides call processing functions by controlling the boundary between sessions in an IP communication network.

Referring to FIG. 1, the mobile core network has a Gi-LAN interface to connect to the Internet, and the Gi-LAN interface is actually an interface through which a packet gateway (P-GW) in the mobile core network connects to a packet data network (PDN). You can. These Gi-LAN service functions can be connected to the data center through a router, and the data center can be connected to the Internet.

According to one embodiment, a packet gateway (P-GW) is a technology used in mobile communication networks to mediate packet transmission between a mobile user device and an IP network. Therefore, P-GW plays an important role in LTE and 5G networks. P-GW enables data transmission between user devices and external IP networks within a mobile communication network, accepting IP packets, inspecting user information and data traffic within the packets, and classifying that information. Afterwards, the packet can be relayed to an appropriate destination based on the information.

According to one embodiment, a router is one of network devices and may serve to connect two or more computer networks and relay the transmission of packets. The router can use the IP address information of the packet to deliver it to the destination. Therefore, the router can transfer data between logically separate networks, and all devices connected to the Internet can communicate through the router.

According to one embodiment, a packet data network (PDN) is a network that provides IP-based data communication and may include various networks such as the Internet, an enterprise network, and a service provider's own network. Mobile users can access a PDN through a mobile communication network and use various services such as the Internet. PDN works in conjunction with mobile communication networks to allow mobile users to access the Internet and transfer data. For this purpose, mobile communication networks use equipment such as P-GW (Packet Gateway) to connect to the PDN and relay data transmitted by users.

According to one embodiment, the router may use a routing algorithm to determine the path of the packet to determine which path the packet should be transmitted. Through this, the router can transmit packets through the optimal path to their destination, playing an important role in various network environments, including the Internet.

According to one embodiment, S/Gi-LAN corresponds to N6-LAN in 5G, and like S/Gi-LAN, mobile communication operators can provide various additional services through various types of service functions through N6-LAN. there is. 3GPP Rel-18 started a standard study to perform N6-LAN traffic control using IETF service function chain (SFC) technology.

Figure 2 shows an example of configuring an N6-LAN according to various embodiments of the present disclosure.

Referring to Figure 2, the 3GPP TR 23.700-18 (Study on system enabler for service function chaining, Rel-18) standard study document can comply with IETF RFC 7665, Service Function Chaining (SFC) Architecture, and can be used in 5G systems (5G It can be assumed that System, 5GS) operates as a traffic classifier shown in FIG. 3. More specifically, the user plane function (UPF) in the 5G system can operate as a classifier for traffic transmitted to N6-LAN. Traffic classifier may refer to equipment or software that analyzes packet data in a network to identify and classify specific traffic.

According to one embodiment, the traffic classifier may analyze the header information of the packet to determine the source, destination, protocol, port number, etc. of the packet. Based on this, specific applications, services, users, groups, etc. can be identified and traffic can be controlled or filtered by applying related policies and rules.

According to one embodiment, a traffic classifier plays an important role in a large-scale network and can bring about effects such as ensuring Quality of Service (QoS), strengthening security, optimizing traffic, and reducing costs. For example, enterprises can use traffic classifiers to prioritize sensitive business data and enforce security policies, such as restricting website access. Additionally, in mobile communication networks, traffic classifiers can be used to control data transmission for each service and user, and to perform traffic management to ensure QoS.

Accordingly, the traffic classified by the traffic classifier of FIG. 3 is processed as a combination of service functions according to each SFP and then delivered to the final DN (data network). In this way, by using SFC technology to provide N6-LAN services and classifying traffic and processing it according to SFP, mobile communication operators can configure N6-LAN, which provides various additional services, with SFC technology.

SFP (service function path) may refer to a path of service functions applied sequentially to process specific traffic. SFP can be used to determine which path specific traffic will follow and which service function it will pass through. An SFP may contain a set of service function IDs, lengths, and sequences. Each service function ID refers to the unique identifier of the service function used in SFC, and the length may indicate the length of data processed by the service function. The order may indicate the order in which the corresponding service functions are processed within the SFP. Service functions within the SFP have their own Service Index (SI), and the service functions can be processed sequentially, with the SI value decreasing by 1 each time a packet moves along the service path.

The network entity function (NEF) in FIG. 2 refers to a function that connects to an external system in a 5G network and exposes network resources. PCF (policy control function) is a policy management function in a 5G network. It refers to the function of applying and managing various policies related to service requests. SMF (session management function) is a function that performs session management in a 5G network, and can be responsible for session management and control with UE (user equipment). UPF (user plane function) is a function responsible for data packet delivery in a 5G network, and can perform IP address conversion and traffic management for packet data delivery. AF is a function that processes and manages data related to applications in a 5G network, and can perform network resource allocation and service quality management.

Figure 3 shows a conceptual diagram of SFC according to various embodiments of the present disclosure.

Referring to FIG. 3, the SFP may be determined by a traffic classifier and the path may be classified. The SF that goes through may vary depending on each SFP.

For example, traffic may be classified as SFP1, SFP2, and SFP3 by a traffic classifier.

In the case of SFP1, it can go through the service functions of SF1, SF2, and SF4. In the case of SFP2, the service functions of SF2 and SF3 can be used. In the case of SFP3, only the service function of SF4 can be used.

The traffic classifier must perform SFC encapsulation so that packets are transmitted along the SFP.

FIG. 4 illustrates an example of a packet format for performing SFC encapsulation according to various embodiments of the present disclosure.

Referring to FIG. 4, FIG. 4 shows a packet format for performing SFC encapsulation as an example of using NSH (network service header) defined in IETF RFC 8300. In order to perform SFC encapsulation, 5GS adds a service path header (SPI) in the packet as shown in Figure 4, enters the SFP ID (identifier) as the SPI value, and enters the SFP length as the Service Index (SI) value. Put it in. While a packet is transmitted along the SFP, service functions within the SFP may decrease the SI value by 1.

According to one embodiment, SPI may be an identifier that identifies a service path. SPI is included in the SFC packet header and can convey information about the service path when the packet is delivered in the SFC domain. SPI can be used to identify service paths in SFC. SFC can be composed of multiple service functions that define service paths and process packets according to each service path. SPI can be used to distinguish these service functions and define the order in which packets are processed in the service path.

According to one embodiment, the SPI value is used to identify service paths and has a unique value for each service path. Since the SPI value is different depending on the service path, SFC can properly process packets according to the service path.

SI may be a value indicating the location at which a packet is processed along the service path. The SI is included in the SFC packet header and can indicate the location of the packet as it is delivered along the service path.

SI is used in SFC when processing packets along the service path. The SI value indicates where the packet is processed on the service path, and each service path may have a different SI value. The SI value is initially set to the length of the service path and is decreased by 1 each time a packet is processed along the service path. Through this, the SI value indicates where the packet is processed along the service path and can be 0 at the last service function.

3GPP Rel-18 has started a standard study to provide N6-LAN services using SFC technology, but a specific method for packet processing for SFC encapsulation has not yet been proposed. Therefore, the present invention manages the information necessary to perform SFC encapsulation in 5GS and proposes a packet processing method for UPF for SFC encapsulation.

Hereinafter, this disclosure proposes a method in which 5GS manages SFC information and UPF performs SFC encapsulation. To this end, a method and related procedures for managing information for SFP encapsulation are disclosed.

Through this disclosure, 5GS can provide N6-LAN service using SFC technology, thereby directly controlling N6-LAN service for specific application traffic at the request of service providers as well as mobile communication providers.

Hereinafter, in order to provide N6-LAN service using SFC technology, the present disclosure first describes a method of managing a policy for performing traffic steering on the N6-LAN interface and the traffic steering policy configured in this way. Based on this, a method and device for performing SFC encapsulation in UPF are disclosed.

Figure 5 shows an example of a method for managing traffic steering policy information in 5GS, according to an embodiment of the present invention.

Referring to FIG. 5, there can be two cases in which traffic steering information is input: one is requested by AF through input from an external operator, and the other is preconfigured within 5GS.

According to each input, PCC (policy and charging control) rules can be stored and managed by dividing them into AF influenced traffic steering and N6-LAN traffic steering information.

PCC (Policy and Charging Control) rules are rules for applying quality of service (QoS) and fee policies in mobile communication networks. PCC rules are created in PCRF (Policy and Charging Rules Function), which allows you to define and apply QoS and charging policies for specific services in the network. PCC rules are created considering various factors such as service type, user group, location, and time. For example, you can set maximum transfer speed, bandwidth limit, priority, etc. for a specific service. Additionally, a fee policy can be set considering the service user's level, usage amount, subscription period, etc. PCC rules are created in the PCRF and applied by the Policy and Charging Enforcement Function (PCEF). Through this, PCEF applies and manages QoS and fee policies for specific services in the network. By applying PCC rules, the network can provide better service quality and pricing policies.

Traffic steering information may be essential information for 5GS to steer N6-LAN traffic in all cases, regardless of the operator's policy or external AF's request.

If SFC service is requested from AF in addition to settings due to the operator's internal policy, this may mean that AF requests 5GS to apply the SFC policy requested for the application using the pre-set SFC ID or SFP ID and metadata. .

In order to transfer the traffic steering information stored in the PCC rule to the UPF in charge of actual packet processing, the SMF can store the traffic steering information in the forwarding action rule (FAR). As explained earlier, even if two types of traffic steering information exist in the PCC rule, only one traffic steering information can be stored in the FAR for UPF to perform packet forwarding.

FAR (Forwarding Action Rule) is one of the rules used in 5G networks defined by 3GPP. FAR is included within the Packet Forwarding Control Protocol (PFCP) message and is used in the User Plane Function (UPF) to process data packets. FAR provides information about packet processing operations performed in UPF. FAR includes parameters related to action information for packet processing. This action information can be used to specify features such as how data packets are assigned to specific services, packet filtering, Network Address Translation (NAT), and Quality of Service (QoS) processing.

FAR is used to specify data packet processing for a specific service. For example, FAR differentiates packet processing for services such as Internet services, streaming services, gaming services, etc. FAR is delivered by a PFCP message, and PFCP may be a protocol for communication between PCF (Policy Control Function) and UPF.

Additionally, FAR is used in UPF to specify packet processing behavior. This allows you to assign data packets to appropriate services, apply QoS processing, and perform various functions such as NAT and packet filtering.

Figure 6 shows an example of a PCC rule that additionally defines traffic steering information necessary to provide an SFC service in a wireless system according to an embodiment of the present invention.

Referring to FIG. 6, newly added traffic steering information may include an SFC/SFP ID and optionally metadata. Metadata can be said to be data that describes information about data, that is, data that explains data. Metadata may include information such as data content, structure, format, properties, source, creation date, etc., and can be used to manage the validity, accuracy, quality, security, etc. of data. Metadata can play an important role in managing your data. If metadata is managed effectively, tasks such as data search, sorting, classification, and verification can be performed efficiently.

Referring to FIG. 6, SFC/SFP ID and metadata option information may be included in both information for controlling N6-LAN traffic steering information and information for controlling AF influenced traffic steering.

In addition, in the case of AF influenced traffic steering, only uplink traffic is currently available for control, so the traffic steering policy identifier is set to be the same as N6-LAN traffic steering to include downlink traffic as well. It can be defined as one or more.

According to the PCC rules of FIG. 6, more than one traffic steering information may exist for one application, but in reality, only one of N6-LAN or AF influenced traffic steering can be applied. That is, even if N6-LAN steering traffic information and AF influenced traffic steering information for the same application exist at the same time, the information actually used for SFC encapsulation may be one. In other words, this may mean that priority is given to two types of traffic steering. The current 3GPP standard specifies that when two types of traffic steering exist, N6-LAN has priority, but according to one embodiment, priority may be determined according to operator policy. Therefore, if both N6-LAN and AF influenced traffic steering information for the same application exist, it can be selected according to the priority determined by the operator. If there is no policy regarding the operator's priority, N6-LAN traffic steering is performed according to the current standard. Information can have priority.

Methods for establishing a policy for performing traffic steering for the N6-LAN interface defined in the PCC rules include (1) a method for a mobile communication service provider to establish an N6-LAN traffic steering policy within 5GS, and (2) an external service There are two ways to establish a traffic steering policy by receiving input from operators.

First, if 5GS has an internal policy for SFC service, it can be managed by adding SFC/SFP ID and optional metadata to the N6-LAN traffic steering information in the PCC rule. As described above, the SFP ID and metadata may be information needed for UPF, which operates as a traffic classifier, to perform SFC encapsulation on packets. According to IETF RFC 7665, an SFP ID is required for SFC encapsulation, and metadata can optionally be added.

Second, when an SFC service is requested from AF, the SFC/SFP ID and metadata received from AF can be stored in the PCC rule. AF can request a preset SFC ID or SFP ID from 5GS. In other words, it asks you to apply the requested SFC policy to the application. In order to provide the SFC service requested by the application, UPF must perform packet processing for SFC encapsulation on actual packets. AF can request SFC/SFP ID and additional metadata to 5GS so that UPF can perform SFC encapsulation on SFC traffic.

Referring to FIG. 6, what is written as Mandatory in the Category can be distinguished as essential information, and what is not written in the Category can be Mandatory or Optional information.

Referring to FIG. 6, according to one embodiment, the Rule Identifier is an identifier that can uniquely identify a PCC rule, and is used with a Policy Control Function (PCF) to refer to a specific PCC rule within a PDU Session. It can be used between SMF (Session Management Function). Rule Identifier can specify data packet priority, transmission speed, access priority, etc. Rule Identifier is used to reference a PCC rule, and can also be used to transfer PCC rules between PCF and SMF. In other words, Rule Identifier is one of the important components for data traffic control and QoS management in 5G networks, and can play an essential role in managing PCC rules.

According to one embodiment, N6-LAN Traffic Steering may be based on Service Function Chaining (SFC) used in 5G networks. N6-LAN Traffic Steering Enforcement Control controls traffic through SFC and may include information necessary to perform traffic steering. N6-LAN Traffic Steering Enforcement Control provides essential information to control traffic in 5G networks using N6-LAN. Through this, mobile communication operators can maintain quality of service (QoS) and provide various additional services to customers.

According to one embodiment, traffic steering policy identifier(s) is a piece of information used to control traffic steering in a 5G network, and is an identifier that refers to a traffic steering policy pre-configured in a Session Management Function (SMF). You can. Information used to control traffic steering can be used to manage and control traffic of a specific Session Protocol Data Unit (PDU) session by referring to a pre-configured traffic steering policy in the SMF. This allows mobile communication providers to use network resources efficiently and maintain quality of service (QoS).

According to one embodiment, SFC/SFP ID(s) may be one of the information required to control and manage traffic using SFC (Service Function Chaining) in a 5G network. SFC/SFP ID(s) is an identifier of the SFC/SFP, and a unique ID may be assigned to each SFC/SFP. SFC/SFP ID(s) can be used to control traffic through the SFC and refer to specific service function paths. Additionally, according to another embodiment, the SFC/SFP ID(s) may include metadata for SFC encapsulation. These SFC/SFP ID(s) give a unique ID to each SFC/SFP, making it possible to accurately control and manage traffic. Additionally, by including metadata for SFC encapsulation, efficient traffic control can be performed in the network.

According to one embodiment, AF influenced traffic steering may mean performing traffic steering according to requirements arising from AF. AF is responsible for running applications on 5G networks and sometimes performs traffic steering to meet specific service requirements. In AF influenced Traffic Steering Enforcement Control, information about traffic steering requirements arising from AF may be provided. Therefore, by processing information about requirements arising from AF in SMF and performing traffic steering, mobile communication service providers can provide stable and high-quality services to customers.

According to one embodiment, Data Network Access Identifier (DNAI) may be an identifier used to identify data network access in a 5G network. DNAI is an identifier for a specific data network and can be used in 5G networks to identify and manage access to that data network. Data Network Access Identifier may include one or more identifiers, and each identifier may indicate information about the corresponding data network. For example, DNAI may include information such as IP address, VLAN ID, service ID, etc. for the data network. DNAI may be needed in 5G networks to efficiently manage access to data networks and identify the destination of PDUs. Therefore, DNAI is one of the important information in 5G networks and is essential to ensure stable access to data networks.

According to one embodiment, Per DNAI: Traffic steering policy identifier(s) may be information used to specify a traffic steering policy for each Data Network Access Identifier (DNAI). Per DNAI: Traffic steering policy identifier(s) can be used in the Session Management Function (SMF). SMF manages traffic steering policies and can apply each policy according to DNAI. For this, it is necessary to reference the traffic steering policy identifier for each DNAI. SMF manages policies for each DNAI and efficiently manages data network access, allowing mobile communication operators to provide stable and high-quality services to customers.

According to one embodiment, Per DNAI: N6 traffic routing information is a piece of traffic steering information for each Data Network Access Identifier (DNAI) and may provide information for specifying traffic routing to the DNAI. Per DNAI: N6 traffic routing information can be used in SMF (Session Management Function). By specifying appropriate traffic routing for each DNAI, mobile carriers can optimize data network access and provide reliable, high-quality services to customers.

According to one embodiment, Per DNAI: SFC/SFP ID(s) is one of the traffic steering information for each Data Network Access Identifier (DNAI), and the Service Function Chain (SFC) and SFP ( Service Function Path) identification information and optional metadata information for SFC encapsulation can be provided. Per DNAI: SFC/SFP ID(s) information can be used in SMF to handle traffic steering and SFC encapsulation for DNAI and efficiently manage traffic to the data network. By specifying appropriate SFC/SFP identification and encapsulation information for each DNAI, mobile communication operators can optimize data network access and provide reliable and high-quality services to customers.

FIG. 7 illustrates an example of information requested for an SFC service by AF using a method of requesting AF influenced traffic routing, according to an embodiment of the present disclosure.

In the present disclosure, by adding an SFC/SFP ID for the SFC service and optional metadata to the AF influenced traffic routing request information requested by the conventional AF, the AF can request 5GS to apply the SFC policy of the application. By using a method where AF requests AF influenced traffic routing, information requested for SFC service can be delivered to PCF through NEF and stored in PCC rules.

AF influenced traffic routing defined in the current 3GPP standard requires AF only for uplink packet routing. However, in the case of SFC service, both uplink and downlink traffic must be applicable. Therefore, when requesting SFC service using the AF influenced traffic routing of the current standard, additional information indicating the traffic direction may be required.

Referring to FIG. 7, in the present disclosure, a traffic direction parameter indicating uplink and downlink for the SFC service can be added to the AF influenced traffic routing information requested by the AF. According to the present disclosure, AF can request SFC service information to perform N6-LAN routing for both bidirectional traffic in the uplink and downlink directions.

Referring to FIG. 7, according to one embodiment, the Traffic Description may be used to define target traffic to be affected, and may be expressed as a combination of DNN and optionally S-NSSAI, application identifier, or traffic filtering information. Traffic Description can be used when PCF selects traffic to apply to PCC rules. DNN stands for Data Network Name, and S-NSSAI can be used as a service designator. The application identifier is used to represent the application, and traffic filtering information can be used to filter traffic based on field values in the packet header. Traffic Description can be classified as mandatory information.

According to one embodiment, Target UE Identifier may indicate the UE targeted by a specific request. The Target UE Identifier may represent an individual UE, multiple UE groups expressed through internal group identifiers, or all UEs accessing a combination of specific DNN, S-NSSAI, and DNAI(s). Target UE Identifier can be used to identify a specific UE to which traffic steering or QoS policy is applied. Target UE Identifier can be classified as Mandatory information.

According to one embodiment, the AF transaction identifier may be an ID for identifying an AF request. AF transaction identifier can be classified as mandatory information.

According to one embodiment, the N6 Traffic Routing requirements relate to optional indication of a routing profile corresponding to each DNAI, N6 traffic routing information corresponding to each DNAI, and traffic correlation. Traffic Direction may be optionally added and may indicate uplink or downlink, depending on one embodiment. N6 Traffic Routing requirements can be classified as Optional information.

According to one embodiment, SFC/SFP ID represents an SFC and SFP identifier, and may optionally include metadata for SFC encapsulation. SFC/SFP ID and metadata can be used to classify traffic and apply service functions in 5G networks. SFC/SFP ID can be classified as optional information.

Traffic Description, Target UE Identifier, AF transaction identifier, N6 Traffic Routing requirements, and SFC/SFP ID shown in FIG. 7 can be applied in PCF or NEF.

Figure 8 shows an example of traffic steering-related information in FAR transmitted from SMF to UPF, according to an embodiment of the present invention.

The PCF transmits the PCC rules to the SMF in the conventional manner, and the SMF can configure the FAR based on the PCC rules received from the PCF. In this disclosure, metadata can be additionally defined as a new SFC/SFP ID and option along with forwarding policy information in the conventional FAR. The newly added SFC/SFP ID and metadata can be used to perform SFC encapsulation of the packet when UPF performs the traffic steering policy.

Referring to FIG. 8, according to one embodiment, the N4 Session ID may identify the N4 session associated with the FAR.

According to one embodiment, Rule ID may be a unique identifier for identifying information.

According to one embodiment, Forwarding policy may refer to a pre-configured traffic steering policy or HTTP redirection. The Forwarding policy may contain one of the following policies identified by the TSP ID:

(1) N6-LAN steering policy to steer subscriber traffic to the appropriate N6 service features deployed by the operator;

(2) a local N6 steering policy that enables traffic steering on the DN's local access according to routing information provided by the AF, as described in clause 5.6.7, and

(3) Values for redirection destination for forwarding behavior (always, after measurement report (if forwarding behavior is “redirect”))

Figure 9 shows an example of a process in which UPF performs packet forwarding, according to various embodiments of the present disclosure.

Referring to FIG. 9, when UPF receives a packet, it can perform packet forwarding according to FAR information. According to one embodiment, FAR information may be received from SMF. FAR may include L6-LAN traffic steering information, and UPF can perform N6-LAN routing according to this information. When performing N6-LAN traffic steering, if SFC encapsulation is required, the SFC/SFP ID and additional metadata in the FAR can be used. In addition, additional information such as header format or transport protocol for SFC encapsulation can use the predefined SFC policy information within 5GS. The predefined SFC policy can also reflect policy information previously agreed upon with AF. Additionally, when UPF performs packet encapsulation, if there is more than one SFP ID(s) where the SFC/SFP ID value defined in FAR is applicable to the actual packet, UPF creates one SFP ID according to the predefined SFC policy. You can choose.

According to one embodiment, a predefined SFC policy may have a mapping relationship or selection method that can select one SFP ID. Therefore, when there are multiple SFP ID(s) corresponding to the SFC/SFP ID value defined in FAR and one of them must be selected, UPF selects one SFP ID according to the predefined SFC policy to encapsulate the packet. It can be used to perform .

Figure 10 shows an example of a procedure for managing traffic steering information requested by AF according to an embodiment of the present invention.

Referring to FIG. 10, the description of UPF, SMF, PCF(s), NEF, and AF may be the same as the description of UPF, PCF, SMF, NEF, and AF of FIG. 2.

EASDF (Edge Application Service Discovery Function) is a function to provide edge application services in a 5G network. EASDF collects location information and service characteristics of edge applications and provides the corresponding information to the UE, helping the UE select an appropriate edge application when using the service. EASDF has interfaces with various entities in the network, and through this, it can provide edge application services using information collected by EASDF.

UDR stands for User Data Repository and can be an element that stores and manages user data in a 5G network. UDR is a data storage used in 5G networks. UDR stores user profiles, policies and other network-related data, and can be used by service providers to optimize services and improve user experience. UDR can also be linked to the network slicing function to store and manage data for each service.

Referring to FIG. 10, when AF requests AF influenced traffic steering from NEF, the request may be made by adding an SFC ID or SFP ID value (1001). The SFC ID may be a unique identifier used to identify an SFC instance, and the SFP ID may be an identifier used to identify the service function chain used in the service path.

NEF can receive the SFC ID or SFP ID from AF using the Nnef_TrafficInfluence_Create/Update/Delete message (1003).

The NEF may store, update, or delete information requested by the AF, including the SFC ID or SFP ID value, in the UDR (1005).

The NEF may transmit the Nnef_TrafficInfluence_Create/Update/Delete Response message to the AF in response to the Nnef_TrafficInfluence_Create/Update/Delete message in operation 1003 (1007).

The UDR may inform the PCF(s) that information in the UDR has been updated (1009).

The PCF(s) may convey new policy information, including the SFC ID or SFP ID, to the SMF (1011).

SMF can transmit FAR forwarding information including SFC ID or SFP ID to UPF/EASDF (1013).

Figure 11 shows an example of a procedure for managing traffic steering information set within 5GS according to an embodiment of the present invention.

Referring to FIG. 11, the PCF may configure N6-LAN traffic steering information including the SFC/SFP ID in the PCC rule and transmit the PCC rule to the SMF (1101).

The SMF may configure a traffic steering policy according to the delivered PCC rules (1103).

The SMF may transmit a FAR including an SFC ID or SFP ID to the UPF using the N4 Session Establishment Modification Request message (1105a).

UPF may respond to the N4 Session Establishment Modification Request message to the SMF using the N4 Session Establishment Modification Response message (1105b)

According to various embodiments of the present disclosure, a method for a 5G system (5GS, 5G System) to support the N6-LAN traffic steering function using SFC technology is that the PCF includes additional information for N6-LAN traffic steering in the PCC rule. steps; SMF generates FAR containing additional information for N6-LAN traffic steering; UPF performs SFC encapsulation using a predefined SFC policy and FAR; may include.

According to one embodiment, the additional information for N6-LAN traffic steering may be an SFC ID or SFP ID and optionally metadata.

According to one embodiment, the PCF may configure PCC rules by distinguishing between cases where additional information for N6-LAN traffic steering is received from AF through NEF and cases where it is set internally.

According to one embodiment, the SMF may receive a PCC rule containing additional information for N6-LAN traffic steering from the PCF, configure a FAR containing the information, and transmit it to the UPF.

According to one embodiment, when the UPF performs SFC encapsulation on a packet, if there is more than one SFP ID(s) corresponding to the SFC/SFP ID stored in the FAR, the UPF encapsulates one SFP ID according to a predefined SFC policy. You can select and perform packet encapsulation.

FIG. 12 illustrates the configuration of a network entity in a wireless communication system according to various embodiments of the present disclosure.

Referring to FIG. 12, the network entity of the present disclosure is a concept that includes a network function according to system implementation. Terms such as 'unit' and 'unit' used hereinafter refer to a unit that processes at least one function or operation, and may be implemented as hardware, software, or a combination of hardware and software. The network entity 1200 according to various embodiments of the present disclosure may include a communication unit 1210, a storage unit 1220, and a control unit 1230 that controls the overall operation of the network entity 1200. The communication unit 1210 transmits and receives signals with other network entities. Accordingly, all or part of the communication unit 1210 may be referred to as a 'transmitter', a 'receiver', or a 'transceiver or transceiver'. The storage unit 1220 stores data such as basic programs, applications, and setting information for the operation of the network entity 1200. The storage unit 1220 may be comprised of volatile memory, non-volatile memory, or a combination of volatile memory and non-volatile memory. And, the storage unit 1220 provides stored data according to the request of the control unit 1230. The control unit 1230 controls the overall operations of the network entity 1200. For example, the control unit 1230 transmits and receives signals through the communication unit 1210. Additionally, the control unit 1230 records and reads data from the storage unit 1220. Additionally, the control unit 1230 can perform protocol stack functions required by communication standards. To this end, the control unit 1230 may include a circuit, an application-specific circuit, at least one processor or microprocessor, or may be part of a processor. Additionally, a portion of the communication unit 1210 and the control unit 1230 may be referred to as a communication processor (CP). The control unit 1230 may control the network entity 1200 to perform any one operation among various embodiments of the present disclosure. The communication unit 1210 and the control unit 1230 do not necessarily have to be implemented as separate modules, and of course, they can be implemented as a single component in the form of a single chip or software block. The communication unit 1210, storage unit 1220, and control unit 1230 may be electrically connected. Additionally, the operations of the network entity 1200 can be realized by providing the network entity 1200 with a storage unit 1200 that stores the corresponding program code. The network entity 1200 includes a network node, AMF, SMF, UPF, NF, NEF, NRF, EASDF, UDM, AF, AUSF, SCP, UDSF, and any one of the network functions shown in FIGS. 1 and 2. It can be.

FIG. 13 illustrates the configuration of a device for supporting an N6-LAN traffic steering function using SFC technology in a wireless communication system according to various embodiments of the present disclosure.

Referring to FIG. 13, terms such as '~unit' and '~unit' used hereinafter mean a unit that processes at least one function or operation, which is implemented by hardware or software, or a combination of hardware and software. It can be. A device 1300 for supporting an N6-LAN traffic steering function using SFC technology according to various embodiments of the present disclosure includes a communication unit 1310, a storage unit 1320, and a control unit that controls the overall operation of the device 1300. It may include (1330). The communication unit 1310 transmits and receives signals with other network entities. Accordingly, all or part of the communication unit 1310 may be referred to as a 'transmitter', a 'receiver', or a 'transceiver or transceiver'. The storage unit 1320 stores data such as basic programs, applications, and setting information for the operation of the network entity 1300. The storage unit 1320 may be comprised of volatile memory, non-volatile memory, or a combination of volatile memory and non-volatile memory. And, the storage unit 1320 provides stored data according to the request of the control unit 1330. The control unit 1330 controls the overall operations of the device 1300. For example, the control unit 1330 transmits and receives signals through the communication unit 1310. Additionally, the control unit 1330 records and reads data from the storage unit 1320. Additionally, the control unit 1330 can perform protocol stack functions required by communication standards. To this end, the control unit 1330 may include a circuit, an application-specific circuit, at least one processor or microprocessor, or may be part of a processor. Additionally, a portion of the communication unit 1310 and the control unit 1330 may be referred to as a communication processor (CP). The control unit 1330 may control the device 1300 to perform any one operation among various embodiments of the present disclosure. The communication unit 1310 and the control unit 1330 do not necessarily have to be implemented as separate modules, and of course, they can be implemented as a single component in the form of a single chip or software block. The communication unit 1310, storage unit 1320, and control unit 1330 may be electrically connected. Additionally, the operations of the device 1300 can be realized by providing the device 1300 with a storage unit 1320 that stores the corresponding program code.

Methods according to embodiments described in the claims or specification of the present disclosure may be implemented in the form of hardware, software, or a combination of hardware and software.

When implemented as software, a computer-readable storage medium that stores one or more programs (software modules) may be provided. One or more programs stored in a computer-readable storage medium are configured to be executable by one or more processors in an electronic device (configured for execution). One or more programs include instructions that cause the electronic device to execute methods according to embodiments described in the claims or specification of the present disclosure.

These programs (software modules, software) include random access memory, non-volatile memory including flash memory, read only memory (ROM), and electrically erasable programmable ROM. (electrically erasable programmable read only memory, EEPROM), magnetic disc storage device, compact disc-ROM (CD-ROM), digital versatile discs (DVDs), or other types of disk storage. It can be stored in an optical storage device or magnetic cassette. Alternatively, it may be stored in a memory consisting of a combination of some or all of these. Additionally, multiple configuration memories may be included.

In addition, the program may be distributed through a communication network such as the Internet, an intranet, a local area network (LAN), a wide area network (WAN), or a storage area network (SAN), or a combination thereof. It may be stored on an attachable storage device that is accessible. This storage device can be connected to a device performing an embodiment of the present disclosure through an external port. Additionally, a separate storage device on a communication network may be connected to the device performing an embodiment of the present disclosure.

In the specific embodiments of the present disclosure described above, elements included in the disclosure are expressed in singular or plural numbers depending on the specific embodiment presented. However, singular or plural expressions are selected to suit the presented situation for convenience of explanation, and the present disclosure is not limited to singular or plural components, and even components expressed in plural may be composed of singular or singular. Even expressed components may be composed of plural elements.

Meanwhile, in the detailed description of the present disclosure, specific embodiments have been described, but of course, various modifications are possible without departing from the scope of the present disclosure. Therefore, the scope of the present disclosure should not be limited to the described embodiments, but should be determined not only by the scope of the patent claims described later, but also by the scope of this patent claim and equivalents.

Claims (20)

In a method for supporting N6-LAN traffic steering function using SFC technology in a wireless communication system
PCF (policy control function) is a process of configuring additional information for N6-LAN traffic steering based on PCC (policy and charging control) rules,
A process of transmitting the configured additional information to a session management function (SMF);
The SMF configures a forwarding action rule (FAR) containing additional information for steering the N6-LAN traffic,
The SMF transmits the FAR including the additional information to a user plane function (UPF),
The UPF includes a process of performing SFC encapsulation based on a predefined SFC policy and FAR. The method according to claim 1, wherein the additional information includes at least one of a service function chaining (SFC) ID or a service function path (SFP) ID. The method of claim 1, wherein the additional information includes metadata. The method of claim 1, wherein the PCF, when additional information for the N6-LAN traffic steering is received from the AF through the NEF, configures a first PCC (policy and charging control) rule,
When the additional information for N6-LAN traffic steering is set internally, it includes a process of configuring a second PCC rule,
The first PCC rule and the second PCC rule are different methods. The method of claim 1, wherein when the UPF performs SFC encapsulation on a packet, if there is one or more identifiers corresponding to the SFC ID or SFP ID stored in the forwarding action rule (FAR), the UPF follows a predefined SFC policy. The process of selecting an identifier according to
A method further comprising performing packet encapsulation based on the one identifier. In a device for supporting N6-LAN traffic steering function using SFC technology in a wireless communication system,
The device includes a policy control function (PCF), a session management function (SMF), and a user plane function (UPF),
The PCF configures additional information for N6-LAN traffic steering based on policy and charging control (PCC) rules,
Transmitting the configured additional information to a session management function (SMF),
The SMF configures a forwarding action rule (FAR) containing additional information for steering the N6-LAN traffic,
The SMF transmits the FAR including the additional information to a user plane function (UPF),
The UPF is a device that performs SFC encapsulation based on a predefined SFC policy and FAR. The device of claim 6, wherein the additional information includes a service function chaining (SFC) ID and a service function path (SFP) ID. The device of claim 6, wherein the additional information includes metadata. The method of claim 6, wherein the PCF configures a first PCC (policy and charging control) rule when additional information for the N6-LAN traffic steering is received from the AF through the NEF,
When the additional information for N6-LAN traffic steering is set internally, configure a second PCC rule,
The first PCC rule and the second PCC rule are different devices. In claim 6,
When the UPF performs SFC encapsulation on a packet, if there is one or more identifiers corresponding to the SFC ID or SFP ID stored in the forwarding action rule (FAR), the UPF creates one identifier according to a predefined SFC policy. choose,
A device that performs packet encapsulation based on the single identifier. In a method of operating UPF (user plane function) in a wireless communication system,
A process of receiving additional information for N6-LAN traffic steering based on policy and charging control (PCC) rules from the policy control function (PCF) via the session management function (SMF);
A method that includes the process of performing SFC encapsulation based on a predefined SFC (service function chaining) policy and FAR (forwarding action rule). The method of claim 11, wherein the additional information includes a service function chaining (SFC) ID and a service function path (SFP) ID. The method of claim 11, wherein the additional information includes metadata. The method of claim 11, wherein when the UPF performs SFC encapsulation on a packet, if there is one or more identifiers corresponding to the SFC ID or SFP ID stored in the forwarding action rule (FAR), the UPF follows a predefined SFC policy. The process of selecting one identifier according to the
The method further includes performing packet encapsulation based on the single identifier. The method of claim 11, wherein the UPF forwards packets based on forwarding action rule (FAR). In UPF (user plane function) in a wireless communication system,
Transmitter and receiver,
Comprising a control unit operably connected to the transceiver unit,
The control unit,
Receives additional information for N6-LAN traffic steering based on policy and charging control (PCC) rules from the policy control function (PCF) via the session management function (SMF),
A device that performs SFC encapsulation based on a predefined SFC (service function chaining) policy and FAR (forwarding action rule). The device of claim 16, wherein the additional information includes a service function chaining (SFC) ID and a service function path (SFP) ID. The device of claim 16, wherein the additional information includes metadata. The method of claim 16, wherein the control unit:
When the UPF performs SFC encapsulation on a packet, if there is one or more identifiers corresponding to the SFC ID or SFP ID stored in the forwarding action rule (FAR), the UPF creates one identifier according to a predefined SFC policy. choose,
A device that performs packet encapsulation based on the single identifier. The device of claim 16, wherein the UPF forwards packets based on forwarding action rule (FAR).