Method, system, and computer-readable medium for enabling transport quality of service (QoS) in 5G networks

Abstract

A method for enabling 5G transport quality of service (QoS) includes receiving a service discovery request from a consumer network function (NF) or a service communication proxy (SCP). The method further includes accessing a 5G transport QoS policy database and determining that a 5G transport QoS policy applies to the service discovery request. In response to determining that the 5G transport QoS policy applies to the discovery request, the method further includes generating a service discovery response message and inserting network layer QoS values ​​for implementing the policy into the service discovery response message. The method further includes transmitting the service discovery response message to the consumer NF or SCP.

Description

[Technical field]

[0001] Priority claim This application claims the benefit of priority to U.S. Patent Application No. 16 / 730,799, filed December 30, 2019, the disclosure of which is incorporated by reference in its entirety into the disclosure of this application.

[0002] Technical Field The subject matter described in this disclosure relates to QoS in 5G networks. More specifically, the subject matter described in this disclosure relates to a method, system, and computer-readable medium for enabling transport QoS in 5G networks. [Background technology]

[0003] background In 5G telecommunications networks, a network node that provides a service is called a producer Network Function (NF). A network node that consumes a service is called a consumer NF. A network function can be both a producer NF and a consumer NF depending on whether it consumes or provides a service.

[0004] A given producer NF may have many service endpoints, where a service endpoint is a combination of an Internet Protocol (IP) address and a port number on the network node hosting the producer NF. Producer NFs register with a Network Function Repository Function (NRF). The NRF maintains NF profiles of available NF instances and the supported services of the NF instances. Consumer NFs can subscribe to receive information about producer NF instances that have registered with the NRF.

[0005] An example of an NF that provides services to user equipment (UE) devices, such as Internet of Things (IoT) devices, is the Access and Mobility Management Function (AMF). The AMF provides registration management, connection management, reachability management, mobility management, and other services for UE devices. The AMF serves as the interface between the radio access network and the rest of the nodes in the 5G core network. The AMF also serves as the access point to network slice services.

[0006] Network slicing is a service provided in 5G networks, where network resources are logically allocated in portions or slices for use by UE devices. Each network slice may provide a particular function or service to the UE. A network slice instance is defined as a set of network functions, where the resources for the network functions are arranged and configured to form and meet a particular set of network requirements or characteristics. For example, a network slice instance for an access network service may be virtualized gNodeB and AMF resources for providing access network services for the UE. A network slice instance for a core network service may include virtualized NRF and network exposure function (NEF) resources configured to provide core network services to the UE, such as IoT.

[0007] In 5G telecommunications networks, it may be desirable to implement policies that guarantee quality of service for different traffic classes. The 3rd Generation Partnership Project (3GPP®) Technical Specification (TS) 29.500 defines an SBI message priority mechanism whereby a 5G consumer NF can set a parameter called 3GPP-SBI message priority in a Hypertext Transfer Protocol (HTTP) header that is used to indicate the priority of the message. Clause 6.8.1 of 3GPP TS 29.500 states that the Service Based Interface (SBI) message priority will be used to provide guidance to 5G core network functions acting as HTTP / 2 clients, servers, or proxies to make throttling decisions regarding overload control. Priority information may also be used for routing and proxying. Servers may also use the priority information to process higher priority requests before lower priority requests.

[0008] The priority mechanism is the 3GPP-SBI message priority parameter mentioned above, which is carried in a custom HTTP header and used to carry message priority between the client and the server. The custom HTTP header enforces the message priority end-to-end between the client and the server. HTTP / 2 clients and servers must support the custom HTTP header to enforce the priority mechanism. The 3GPP-SBI message priority parameter carried in the custom HTTP header can be used to set message-level priority or stream priority. Message-level priority is used by the HTTP client or server to indicate the priority of a request from the client or a response from the server. Stream-level priority is used to represent how the sender prefers to prioritize streams for transmitting frames when there is limited capacity to transmit and how the peer allocates resources when managing concurrent streams. Setting the stream priority ensures priority handling for messages between the two endpoints of an HTTP / 2 connection. Summary of the Invention [Problem to be solved by the invention]

[0009] One problem with using the SBI message priority HTTP header mechanism defined in 3GPP TS29.500 is that it requires nodes to support layer 7 in order to realize the priority mechanism. Layer 3 / 4 devices such as network routers may not support layer 7 priority. In addition, even if such intermediate nodes can be configured to support layer 7, parsing layer 7 data requires additional processing and therefore impacts performance. Most intermediate nodes are limited to making routing decisions based on Open Systems Interconnection (OSI) layers 3 and 4. As a result, in layers 3 and 4, all 5G messages are treated the same by intermediate nodes such as routers. Routers may not be able to provide the requested priority between consumer and producer NFs. In addition, when a router is in the path between different NFs serving different 5G network slices, the router cannot differentiate between traffic that may require different priority treatment. During congestion, the router cannot apply congestion policies without a discriminator at the transport or network layer. As a result, traffic in the network slice that expects ultra-low latency may be unacceptably delayed.

[0010] In light of these challenges, therefore, there is a need for methods, systems, and computer-readable media for enabling transport quality of service in 5G networks. [Means for solving the problem]

[0011] overview A method for enabling 5G transport quality of service (QoS) includes receiving a service discovery request from a consumer network function (NF) or a service communication proxy (SCP). The method further includes accessing a 5G transport QoS policy database and determining that a 5G transport QoS policy applies to the service discovery request. The method further includes generating a service discovery response message in response to determining that the 5G transport QoS policy applies to the service discovery request and inserting network layer QoS values ​​to implement the policy into the discovery response message. The method further includes transmitting the service discovery response message to the consumer NF or SCP.

[0012] According to another aspect of the subject matter described in this disclosure, receiving a service discovery request from a consumer NF or an SCP includes receiving a service discovery request from a consumer NF.

[0013] According to yet another aspect of the subject matter described in this disclosure, receiving a service discovery request from a consumer NF or an SCP includes receiving a service discovery request from an SCP.

[0014] According to another aspect of the subject matter described in this disclosure, accessing the 5G transport QoS database includes accessing the 5G transport QoS database using a service identifier extracted from the service discovery request. Transport QoS This includes accessing a database.

[0015] According to another aspect of the subject matter described in this disclosure, a service identifier identifies a service endpoint and an application programming interface (API) resource associated with the service endpoint.

[0016] 2. The method of claim 1, wherein accessing the 5G transport QoS policy database includes accessing the 5G transport QoS policy database using a source public land mobile network (PLMN) identifier.

[0017] According to another aspect of the subject matter described in this disclosure, the network layer QoS value includes a differentiated services code point (DSCP) value.

[0018] According to another aspect of the subject matter described in this disclosure, the network layer QoS values ​​include Internet Protocol (IP) Type of Service (ToS) values.

[0019] According to another aspect of the subject matter described in this disclosure, a method for providing 5G transport QoS includes providing transport QoS for 5G message exchanges between a consumer NF or SCP and a producer NF providing a service requested in a service discovery request using network layer QoS values.

[0020] According to another aspect of the subject matter described in this disclosure, providing transport QoS for the 5G message using a network layer QoS value includes applying a QoS corresponding to the QoS value to a network layer message carrying the 5G message.

[0021] According to another aspect of the subject matter described in this disclosure, a system for enabling 5G transport quality of service (QoS) includes a network function repository function (NRF) including at least one processor and a memory. The system further includes a 5G transport quality of service QoS database located in the memory. The system further includes a 5G QoS-enabled service discovery manager realized by the at least one processor for receiving a service discovery request from a consumer network function (NF) or a service communication proxy (SCP), accessing a 5G transport QoS policy database, determining that a 5G transport QoS policy applies to the service discovery request, and in response to determining that the 5G transport QoS policy applies to the service discovery request, generating a service discovery response message, inserting a network layer QoS value for implementing the policy into the discovery response message, and transmitting the service discovery response message to the consumer NF or SCP.

[0022] According to another aspect of the subject matter described in this disclosure, a 5G QoS-enabled service discovery manager is configured to receive a service discovery request from a consumer NF.

[0023] According to another aspect of the subject matter described in this disclosure, a 5G QoS-enabled service discovery manager is configured to receive a service discovery request from an SCP.

[0024] According to another aspect of the subject matter described in this disclosure, the 5G QoS-enabled service discovery manager uses the service identifier extracted from the service discovery request to discover the 5G QoS-enabled service. Transport QoS It is configured to access a database.

[0025] According to another aspect of the subject matter described in this disclosure, a service identifier identifies a service endpoint and an application programming interface (API) resource associated with the service endpoint.

[0026] According to another aspect of the subject matter described in this disclosure, the 5G QoS-enabled service discovery manager is configured to access a 5G transport QoS policy database using a source public land mobile network (PLMN) identifier.

[0027] According to another aspect of the subject matter described in this disclosure, the network layer QoS value includes a Differentiated Services Code Point (DSCP) value.

[0028] According to another aspect of the subject matter described in this disclosure, the network layer QoS values ​​include Internet Protocol (IP) Type of Service (ToS) values.

[0029] According to another aspect of the subject matter described in this disclosure, the NF or SCP is configured to tag network layer packets with a QoS value to indicate the QoS requested for the 5G message to an intermediate router.

[0030] According to yet another aspect of the subject matter described in the present disclosure, a non-transitory computer-readable medium is provided having executable instructions stored thereon that, when executed by a processor of a computer, control a computer to perform steps. The steps include receiving a service discovery request from a consumer network function (NF) or a service communication proxy (SCP). The steps further include accessing a 5G transport QoS policy database and determining that a 5G transport QoS policy applies to the service discovery request. The steps further include generating a service discovery response message in response to determining that the 5G transport QoS policy applies to the service discovery request and inserting a network layer QoS value for implementing the policy into the discovery response message. The steps further include transmitting the service discovery response message to the consumer NF or SCP.

[0031] The subject matter described in this disclosure may be implemented in hardware, software, firmware, or any combination thereof. Thus, the terms "function", "node" or "module" as used in this disclosure refer to hardware that may also include software and / or firmware components to implement the described features. In one exemplary implementation, the subject matter described in this disclosure may be implemented using a computer-readable medium that stores computer-executable instructions that, when executed by a processor of a computer, control a computer to perform steps. Exemplary computer-readable media suitable for implementing the subject matter described in this disclosure include non-transitory computer-readable media such as disk memory devices, chip memory devices, programmable logic devices, and application specific integrated circuits. In addition, computer-readable media implementing the subject matter described in this disclosure may be located on a single device or computing platform or distributed across multiple devices or computing platforms.

[0032] The subject matter described in the present disclosure will now be described with reference to the accompanying drawings. [Brief description of the drawings]

[0033] [Figure 1] FIG. 1 is a network diagram illustrating an example 5G network architecture. [Diagram 2] FIG. 1 is a message flow diagram illustrating communication of Differentiated Services Code Point (DSCP) values ​​to a consumer NF and use of the DSCP values ​​to prioritize traffic between the consumer NF and a producer NF. [Diagram 3] 1 is a flowchart illustrating an example process that may be implemented by an NRF in responding to a service discovery request from a consumer NF and communicating a DSCP value to the consumer NF in a discovery response. [Figure 4]FIG. 1 is a network diagram showing consumer NFs and producer NFs connected to each other by intermediate routers and realizing different network slices. [Diagram 5] FIG. 13 is a message flow diagram illustrating example messaging associated with communicating DSCP values ​​to a service communication proxy (SCP) and using the DSCP values ​​for indirect communication between the SCP and a producer NF. [Figure 6] FIG. 1 is a network diagram illustrating communication between a consumer NF and a producer NF via an SCP and intermediate routers. [Figure 7] FIG. 1 is a block diagram illustrating an example NRF for providing 5G transport policy information to achieve 5G transport QoS. [Figure 8] 1 is a flowchart illustrating an example process for providing 5G transport QoS. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0034] Detailed Description FIG. 1 is a block diagram illustrating an example 5G system network architecture. In FIG. 1, the network includes an NRF 100 and a service communication proxy (SCP) 101. As mentioned above, the NRF 100 may maintain a profile of available producer NF service instances and their supported services, allowing consumer NFs or SCPs to subscribe to new / updated producer NF service instances and be notified of their registration. The SCP 101 may also support service discovery and selection of producer NFs. In addition, the SCP 101 may perform load balancing of connections between consumer NFs and producer NFs.

[0035] The NRF 100 is a repository of NF profiles. To communicate with a producer NF, a consumer NF or SCP must obtain an NF profile from the NRF 100. An NF profile is a JavaScript Object Notation (JSON) data structure. An NF profile definition includes at least one of a fully qualified domain name (FQDN), an Internet Protocol (IP) version 4 (IPv4) address, or an IP version 6 (IPv6) address.

[0036] As described in more detail below, the NRF may store 5G transport QoS policy information to implement 5G transport QoS between consumer NFs and producer NFs. In one implementation, the NRF 100 will maintain this information in a 5G transport QoS policy database and may provide 5G transport QoS information from this database in response to service discovery requests from consumer NFs.

[0037] In FIG. 1, any node (other than SCP 101 and NRF 100) can be either a consumer NF or a producer NF depending on whether they are consuming or providing a service. In the illustrated example, the node includes a Policy Control Function (PCF) 102 that performs policy-related operations in the network, a User Data Management (UDM) Function 104 that manages user data, and an Application Function (AF) 106 that provides application services. The node shown in FIG. 1 further includes a Session Management Function (SMF) 108 that manages a session between the AMF 110 and the PCF 102. The AMF 110 performs mobility and registration management operations similar to those performed by a Mobility Management Entity (MME) in a 4G network. The AMF 110 also serves as an access point for network slice services. The AMF 110 may also perform AMF selection to select a serving AMF that will provide access to the network slice service requested by the UE during registration.

[0038] An Authentication Server Function (AUSF) 112 performs authentication services for User Equipment (UE), such as UE 114, seeking access to the network.

[0039] The network slice selection function (NSSF) 116 provides network slice subnet availability information (NSSAI) and NS selection services for devices seeking to access a particular network function. The NSSF 116 may obtain AMF loading information from the NRF and obtain NSSAI availability information from the AMF. The NSSF 116 may store the AMF loading information and the NSSAI availability information in an AMF selection database maintained by the NSSF 116. When the NSSF 116 receives an NSSAI selection request from the AMF, the NSSF 116 may utilize the stored AMF loading information and the NSSAI availability information to calculate an AMF relevance score and weight of each AMF that can support the network slice service requested by the UE seeking access to the network slice service. The NSSF 116 may generate a prioritized list of AMFs capable of providing the requested service and corresponding weights and communicate the list to the requesting AMF. The requesting AMF may then use the prioritized list of AMFs and weights to select an AMF for providing access to the requested network slice service.

[0040] The Network Exposure Function (NEF) 118 provides an Application Programming Interface (API) for application functions that want to obtain information about Internet of Things (IoT) devices and other UEs connected to the network. The NEF 118 performs a function similar to the Service Capability Exposure Function (SCEF) in 4G networks.

[0041] The Radio Access Network (RAN) 120 connects the UE 114 to a network via a wireless link. The Radio Access Network 120 may be accessed using a gNodeB (gNB) (not shown in FIG. 1) or other wireless access points. The User Plane Function (UPF) 122 may support various proxy functions for user plane services. One example of such a proxy function is a Multi-Path Transmission Control Protocol (MPTCP) proxy function. The UPF 122 may also support a performance measurement function that may be used by the UE 114 to obtain network performance measurements. Also shown in FIG. 1 is a Data Network (DN) 124 through which the UE accesses data network services, such as Internet services.

[0042] The Service Edge Protection Proxy (SEPP) 126 filters incoming traffic from another PLMN and performs topology hiding for traffic leaving the home PLMN. The SEPP 126 may communicate with a SEPP in the foreign PLMN that manages security for the foreign PLMN. Thus, traffic between NFs in different PLMNs may traverse at least two SEPP functions, one for the home PLMN and one for the foreign PLMN.

[0043] As mentioned above, it is desirable to provide transport quality of service for 5G network traffic. One particular application of such transport quality of service is network slicing. Network slicing is used in 5G networks to provide services based on target capabilities. Examples of such capabilities include ultra-reliable low latency communications, large scale IoT, and emergency services. When exchanging 5G messages, a consumer NF may communicate with a dedicated producer NF for a slice, a shared producer NF between different slices, or a service hosted on a PLMN-neutral producer NF. It is therefore important that a consumer NF can ensure that transport priorities are set for 5G messages and for messages returning from the producer NF to the consumer NF, such that the 5G messages can be processed accordingly by intermediate network nodes before they reach the producer NF. However, requiring the consumer NF to individually set 5G transport priorities is a burden on the consumer, and the consumer NF may not be in the best position to know what type of QoS policy to define for a given message.

[0044] Network devices such as routers have fixed resources. Thus, they have limited capacity and performance. For various technical and operational reasons, there are shared network resources, e.g., common network routers, that are in the path of multiple network slices and network functions. One mechanism that can be used to provide transport quality of service in network routers is the Differentiated Services field, specifically the Differentiated Services Code Point (DSCP) portion of the Differentiated Services field in IP version 4 and IP version 6 headers. The Differentiated Services field is defined in Internet Engineering Task Force (IETF) RFC2474. The DSCP portion of the Differentiated Services field is added to the Per-Hop Behavior (PHB), which is defined as an externally observable forwarding treatment applied to a behavior aggregate at a Differentiated Services compliant node. Thus, the DSCP field is an exemplary field that can be used by network routers to provide differentiated services for different packets.

[0045] The Differentiated Services field replaces the IP Version field for Type of Service (ToS). The IP ToS field can also be used by compliant routers to identify packets associated with different service classes and provide differentiated treatment for such packets based on the ToS value.

[0046] 3GPP TS 23.501 describes DSCP handling for user data, but does not provide guidelines or recommendations for control traffic. Section 6.8.8 of 3GPP TS 29.500 states the following regarding DSCP values:

[0047] ●Multiple HTTP / 2 connections between the two HTTP / 3 endpoints are required: one per DSCP value. All messages sent over the connection are assigned the same traffic class and receive the same DSCP marking.

[0048] ● 3GPP-SBI message priority value shall be taken into account in the selection of the appropriate connection to send the message.

[0049] These loosely defined criteria introduce ambiguity as to when and how a client NF instance performs DSCP marking for a given service of a producer NF. For example, in the case of a 3GPP-SBI message priority having value 5 for a service destined for a producer NF in the same geographic location to an NF in a different PLMN. Similarly, when NF slices are present, there is no guidance on how DSCP is used by a common NF when routing messages to a given NF associated with a particular network slice. The configuration and mapping between DSCP values ​​and priority policies at each consumer NF instance is cumbersome and error prone.

[0050] The subject matter described in this disclosure provides a centralized solution where a network operator establishes custom policies for consumer and producer NFs to set appropriate DSCP bits in the differentiated services field of selected messages. The subject matter described in this disclosure also allows the network operator to manage SBI priority parameters and other fields that may be used to differentiate packets to provide different qualities of service. According to the subject matter described in this disclosure, the NRF defined in 3GPP TS 29.510 may act as a centralized location where the network operator defines customized policies including the appropriate DSCP settings to be used by each client / consumer NF when requesting services from a given producer NF. The customized policies may be communicated by the NRF to the consumer NF in vendor-specific extensions of messages communicated from the NRF to the consumer NF. The vendor-specific extensions are defined in section 6.6.3 of 3GPP TS 29.500. According to 3GPP TS29.500, information elements transmitted over the 3GPP 5G Core (5GC) API should be extensible with vendor-specific data. The definition of JSON data structures using OpenAPI as the interface definition language allows the extension by default of any JSON object with additional member elements. Such vendor-specific extensions can be used in requests and responses between the NRF and the service consumer to communicate values ​​required to implement the transport QoS and the 5G network.

[0051] In the consumer NF, behaviors are defined to enforce policies corresponding to DSCP values. Custom behaviors can be enabled through any of the following modes:

[0052] A consumer NF that supports vendor-specific extensions and therefore applies / manages DSCP values ​​for corresponding services and NFs.

[0053] If a client or consumer NF does not support the vendor-specific extensions, a proxy model using SCP can be used to enable DSCP for NFs that do not support the vendor-specific extensions.

[0054] As mentioned above, the DSCP value can be used to define per-hop behaviors that define the packet forwarding characteristics that a router applies to a particular class of traffic. Different per-hop behaviors can be defined, for example, to provide low loss or low latency service. As defined in RFC2474, the DSCP value is the upper 6 bits of the IP Version 4 Type of Service field and the IP Version 6 Traffic Class field.

[0055] The DSCP parameter value can be set using socket options in Linux or other operating systems that use sockets to define TCP / IP endpoints. For example, in Linux, the setsockopt command can be used to set the value of the option IP ToS or IPv6 T-Class. Standard ToS flags that are defined include: IP ToS Low Latency to minimize delays for interactive traffic; IP ToS throughput to optimize throughput; IP ToS reliability for optimal reliability.

[0056] In addition to the standard values, you can use netfilter rules to set customized values, for example, for destination IP address 10.178.254.160, port 10240, set DSCP value 20 (AS 22): iptables -A OUTPUT -t mangle -p tcp -d 10.178.254.160 - dport 10240 - j DSCP - set-dscp 0x14. Thus, the NRF can instruct the consumer NF to set the DSCP value using any of these mechanisms.

[0057] As mentioned above, the subject matter described in this disclosure allows a network operator to define custom policies to inform consumer NFs about which DSCP value should be applied for a given service and / or NF instance. For example, one policy may be a policy serving UDM_xxx, with an endpoint atlanta.oracle.com, and setting the DSCP value to 26. The custom DSCP policy configured by the network operator is optional and has no functional impact on existing 5G function flows. Only NFs that take advantage of this optional feature will take advantage of it to set up message flows to achieve quality of service. In other words, the mechanism described in this disclosure is backward compatible with NFs that do not support the new quality of service mechanism.

[0058] As mentioned above, policies configured by the network operator may be set in the NRF. The NRF may map DSCP values ​​to a given service endpoint or set of endpoints. Table 1 below shows examples of policy rules and corresponding DSCP values ​​that may be configured in the NRF.

[0059] [Table 1]

[0060] In Table 1, policy rules are defined that map policy values ​​and / or API resources to DSCP values. For example, the first policy in Table 1 maps the IP endpoint 10.75.0.0 / 16 and the corresponding API resource nudm-sdm / * to a DSCP value of 20. This means that any UDM NF instance that exposes this IP address as a service endpoint for SDM services will be assigned the DSCP value of 20. The second policy rule in Table 1 maps the fully qualified domain name (FQDN) of nudm-sdm.atlanta.oracle.com and the specific API resource to a DSCP value of 24. The third policy in Table 1 maps the udm-sdm service for a range of PLMNs to a DSCP value of 30. The fourth policy rule maps any service realized between a given source PLMN and a destination PLMN to a DSCP value of 20.

[0061] It should be noted that the example policies in Table 1 are for illustrative purposes only, and the subject matter described in this disclosure allows a network operator to define any customized policy in the NRF and map that policy to a DSCP value or other network layer QoS value. As described in more detail below, when a consumer NF requests a service, the service request typically provides the target PLMN and the requesting PLMN during the service discovery process. These parameters may be used by the NRF to perform a lookup in a 5G transport QoS database to determine the DSCP value to apply to a message or group of messages. The NRF stores the 5G transport QoS policy mapping database in its persistent memory.

[0062] FIG. 2 is a message flow diagram illustrating example messages exchanged between a consumer NF, an NRF, and a producer NF, implementing the customized policy described in this disclosure. Referring to FIG. 2, in line 1 of the message flow diagram, the consumer NF 200 sends a service discovery request to the NRF 100. The service discovery request identifies the service requested by the consumer NF 200 and also identifies the consumer NF 200. The NRF 100 performs a lookup in its 5G transport QoS policy database to identify the policy to apply to the service. Here, it is assumed that the policy is configured in the database from which the DSCP value is extracted. Thus, the NRF 100 puts the DSCP value in a vendor-specific extension of the discovery response message and in line 2 sends the discovery response message to the consumer NF 200 with the vendor-specific extension containing the DSCP value. In this example, it is assumed that the consumer NF 200 supports the vendor-specific extension and performs the following steps:

[0063] 1. Add a "3GPP SBI-Message-Priority" header to the HTTP2 request event and expose the DSCP value as the SBI message priority value.

[0064] 2. Look for a connection [target IP+port] that is initiated with the requested DSCP value: -If not found: • Use low-level socket APIs to set the DSCP value when initiating an HTTP2 (TCP) connection with the producer NF service (step 3 in Figure 2).

[0065] ◆On such a connection, only messages related to that service and DSCP value should be initiated.

[0066] ● This requirement is substantial when a producer NF 202 is deployed with multiple services and all the services of the producer NF 202 share the same common front-end FQDN (eg, the FQDN of the API Gateway).

[0067] -If found, use that connection. 3. If the consumer NF 200 does not support the socket API to set the DSCP value, the NRF 100 will use NetFilter (i.e., iptables) to set a rule for the “OUTPUT” chain in the “mangle” table to set the DSCP for the destination IP address and port, with the protocol set as TCP.

[0068] In this case, if the producer NF 202 has multiple services hosted on a similar IP address and port pair, the DSCP value will be set for all packets destined to that endpoint.

[0069] In line 4, consumer NF 200 and producer NF 202 exchange service traffic over a TCP connection and use the DSCP value in the service traffic. The initial service message from consumer NF 200 includes the DSCP value as a 3GPP SBI message priority header, but subsequent messages may have the same or higher SBI message priority value based on local policy. Intermediate routers use the DSCP value to provide transport QoS for 5G traffic carried in network (IP) layer packets.

[0070] FIG. 3 is a flow chart illustrating example steps performed by the NRF 100 upon receiving a service discovery request from a consumer NF, such as the consumer NF 200 shown in FIG. 2. Referring to FIG. 3, in step 300, the NRF 100 receives a service discovery request. In step 302, the NRF 100 performs a TS 29.510 procedure to generate a service discovery response. In step 304, if the response set is not empty, control proceeds to steps 306, 308, 310, and 312, where the NRF 100 determines whether a custom policy is defined for the service object, and if so, adds a vendor-specific extension to each matching NF service object that includes a DSCP value. Determining whether a custom policy is defined may include performing a lookup in a 5G transport QoS database based on parameters in the service discovery request. In one example, the NRF may execute service logic to identify a vendor-specific extension configured by the network operator. The vendor-specific extension may be of the form:

[0071]

number

[0072] In the above example, nnnnnn is an IANA assigned code for a particular network equipment vendor, e.g., code 111 is for Oracle, 323 is for Tekelec, etc. <number>The parameter holds the DSCP value to be applied to the connection. If multiple overlapping policies apply to a given service query, in one example, the NRF selects a DSCP value based on the local policy and returns the DSCP value in the service discovery response.

[0073] Once all of the vendor-specific extensions and DSCP values ​​have been added to the response, control proceeds to step 314, where the NRF 100 sends the response to the consumer NF 200. Once a TCP / IP connection is set up, packets sent over the connection can be marked with the DSCP value assigned to the service by the NRF 100. Intermediate switches and routers use the DSCP value to identify the class of service of received packets and provide the appropriate quality of service.

[0074] Figure 4 shows producer NFs and consumer NFs connected via intermediate routers. Referring to Figure 4, consumer NFs 400, 402, and 404 are connected to producer NFs 406, 408, and 410 via intermediate routers 412, 414, 416, and 418. Consumer NF 400, producer NF 406, and intermediate router 412 are exclusively part of the low-latency slice. Consumer NF 404, intermediate router 416, and producer NF 410 are part of the default slice. Consumer NF 402, intermediate routers 414 and 418, and producer NF 408 are shared between the low-latency slice and the default slice. If the consumer NFs and producer NFs support 5G QoS marking of packets as described above, the intermediate routers 412, 414, 416, and 418 can provide the required transport QoS for 5G traffic that is consistent with the policies defined by the network operator in the NRFs.

[0075] If the client does not support vendor-specific extensions for communicating DSCP values, differentiated quality of service may be realized between the SCP and the producer NF providing the service. Quality of service is realized between the SCP and the producer NF, not between the consumer NF and the producer NF. Discovery is also delegated to the SCP. Figure 5 shows the procedure when the consumer NF does not support vendor-specific extensions. In Figure 5, at line 1 of the message flow diagram, the consumer NF 500 sends a 5G service request message to the SCP 101. At line 2, in response to the 5G service request message, the SCP 101 sends a service discovery request to the NRF 100. The NRF 100 performs a lookup in its 5G transport QoS policy database and identifies the DSCP value to be assigned to the service. At line 3, the NRF 100 returns the DSCP value to the SCP 101 in the vendor-specific extension.

[0076] In line 4 of the message flow diagram, the SCP 101 establishes a TCP connection with the producer NF 502 with the required DSCP value. In line 5, service traffic is exchanged between the SCP 101 and the producer NF 502 with the required DSCP value in the individual packets. The initial service message from the SCP includes the DSCP value as a 3GPP SBI message priority header, but subsequent messages may have the same or higher SBI message priority value based on the SCP local policy. Intermediate routers extract the DSCP value from the IP header and use the DSCP value to provide differentiated quality of service for packets associated with different services.

[0077] Figure 6 illustrates the use of DSCP values ​​to implement differentiated transport quality of service between SCPs and producer NFs. Referring to Figure 6, consumer NFs 600 and 602 access network services through SCPs 101A and 101B, respectively. Consumer NF 600 receives low-latency services from producer NF 604 and producer NF 606. Producer NF 604 is used exclusively by the low-latency network slice. Producer NF 606 is used by the low-latency network slice and the default slice.

[0078] The consumer NF 602 accesses a default slice for the service. The default slice service is provided by the producer NF 608 and the producer NF 606. In FIG. 6, it is assumed that the steps of FIG. 5 are performed to establish TCP connections with appropriate DSCP values ​​between SCP 101A and the producer NFs 604 and 606, and between SCP 101B and the producer NFs 606 and 608. When SCP 101A and 101B send service traffic to the producer NFs 604, 606, and 608, the service traffic is received by the intermediate routers 610, 612, 614, and 616. The intermediate routers 610, 612, 614, and 616 extract the DSCP value from the network layer packet (such as an IP packet) and apply transport QoS processing to the network layer packet corresponding to the DSCP value. By applying QoS to network layer packets carrying 5G messages, intermediate routers 610, 612, 614, and 616 provide transport QoS for 5G message traffic. Such 5G message traffic may include 5G messages related to service discovery, 5G content services, 5G subscriptions, etc.

[0079] FIG. 7 is a block diagram illustrating an example NRF for enabling 5G transport quality of service. With reference to FIG. 7, the NRF 100 includes at least one processor 700 and a memory 702. A 5G transport QoS policy database 704 resides in the memory 702. The 5G transport QoS policy database 704 includes policies, such as those illustrated in Table 1, that map service parameters to DSCP values. A 5G transport QoS-enabled discovery manager 706 receives service discovery requests from consumer NFs, accesses the 5G transport QoS policy database 704 to extract policies for the services identified by the discovery request, and provides DSCP values ​​corresponding to the policies extracted from the database 704 to the consumer NFs.

[0080] Figure 8 is a flow chart illustrating exemplary overall steps performed by the NRF 100 to process a service discovery request. These steps are similar to those shown in Figure 3, except that they are described at a higher level. With reference to Figure 8, in step 800, a service discovery request is received from a consumer NF or an SCP. For example, the NRF 100 may receive a service discovery request directly from a consumer NF in a direct model, or from an SCP in an indirect communication model.

[0081] In step 802, the NRF accesses a 5G transport quality of service database to determine whether a policy applies to the service discovery request. For example, the NRF 100 may perform a lookup in the 5G transport QoS policy database 704 using parameters from the service discovery request that identify the source of the service, the destination of the service, the type of service, etc.

[0082] In step 804, the NRF determines whether a policy applies. If a policy applies, control proceeds to step 806, where the NRF provides a DSCP value to implement the policy to the consumer NF in a discovery response message. If a policy does not apply, control proceeds to step 808, where the NRF responds to the service discovery request without a DSCP value or with a default DSCP value. The NF or SCP receiving the service discovery response inserts the DSCP value into network layer messages sent between the NF or SCP and the remote NF. Intermediate routers between the NF or SCP and the remote NF utilize the DSCP value to provide network layer QoS treatment corresponding to the DSCP value for the network layer message, thereby providing QoS for the 5G message carried by the network layer message.

[0083] Thus, using the steps of FIG. 8, the NRF can be used to communicate DSCP values ​​to consumer NFs to achieve network operator defined 5G transport quality of service without requiring the decision logic to be implemented by all consumer NFs.

[0084] The disclosure of each of the following references is incorporated by reference in its entirety into this disclosure. References 1. "3 rd Generation Partnership Project; Technical Specification Group Core Network and Terminals;5G System; Network Function Repository Services; Stage 3 (Release 16)," 3GPP TS 29.510 V16.1.1 (2019-10). twenty three rd Generation Partnership Project; Technical Specification Group Core Network and Terminals; 5G Systems; Technical Realization of Service Based Architecture; Stage 3 (Release 16), 3GPP TS 29.500, V16.1.0 (2019-09). 3. "3 rd Generation Partnership Project; Technical Specification Group Services and System Aspects; System Architecture for the 5G System (5GS); Stage 2 (Release 16), 3GPP TS 23.501 V16.1.0 (2019-09). 4. Nichols et al., "Definition of the Differentiated Services Field (DS Field) in the IPv4 and IPv6 Headers," Internet Engineering Task Force (IETF) Network Working Group Request for Comments (RFC) 2474, The Internet Society, (December 1998). It will be understood that various details of the presently disclosed subject matter may be changed without departing from the scope of the presently disclosed subject matter. Further, the foregoing description is for purposes of illustration only, and not for purposes of limitation.< / number>

Claims

1. A method for enabling 5G transport quality of service (QoS), comprising: receiving a service discovery request from a consumer network function (NF) or a service communication proxy (SCP); accessing a 5G transport QoS policy database and determining that a 5G transport QoS policy applies to the service discovery request; in response to determining that a 5G transport QoS policy applies to the service discovery request, generating a service discovery response message and inserting into the service discovery response message network layer QoS values ​​usable by a network node to implement the 5G transport QoS policy; and sending the service discovery response message to the consumer NF or the SCP.

2. The method of claim 1 , wherein receiving a service discovery request from a consumer NF or an SCP comprises receiving the service discovery request from the consumer NF.

3. The method of claim 1 , wherein receiving the service discovery request from the consumer NF or SCP comprises receiving the service discovery request from the SCP.

4. The method of any one of claims 1 to 3, wherein accessing the 5G transport QoS policy database comprises accessing the 5G transport QoS policy database using a service identifier extracted from the service discovery request.

5. The method of claim 4 , wherein the service identifier identifies a service endpoint and an application programming interface (API) resource associated with the service endpoint.

6. The method of any one of claims 1 to 5, wherein accessing the 5G transport QoS policy database includes accessing the 5G transport QoS policy database using a source Public Land Mobile Network (PLMN) identifier.

7. The method of any one of claims 1 to 6, wherein the network layer QoS value comprises a Differentiated Services Code Point (DSCP) value.

8. The method of any one of claims 1 to 7, wherein the network layer QoS values ​​include Internet Protocol (IP) Type of Service (ToS) values.

9. The method according to any one of claims 1 to 8, comprising using the network layer QoS values ​​to provide transport QoS for 5G messages exchanged between the consumer NF or the SCP and a producer NF providing the service requested in the service discovery request.

10. 10. The method of claim 9, wherein using the network layer QoS value to provide transport QoS for the 5G message includes applying a QoS corresponding to the network layer QoS value to a network layer message carrying the 5G message.

11. The method according to any one of claims 1 to 10, wherein the consumer NF or SCP is configured to tag network layer packets with the network layer QoS value to indicate the QoS required for 5G messages to an intermediate router.

12. A program for causing a computer to carry out the method according to any one of claims 1 to 11.

13. A system for enabling 5G transport quality of service (QoS), comprising: At least one processor; Memory, A 5G transport QoS policy database configured in the memory; A system comprising: a storage medium storing the program according to claim 12.

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