Resource context for a pdu session in a upf

Abstract

Disclosed herein is a method, performed by a User Plane Function (UPF) in a wireless communication core network, of providing a resource context established for a Protocol Data Unit (PDU) session. The method comprises: receiving, from a Network Function (NF), a request for the resource context, the request including a key uniquely identifying the resource context; and providing to the NF the identified resource context.

Description

Applicant’s Ref. P107728WO01 RESOURCE CONTEXT FOR A PDU SESSION IN A UPF TECHNICAL FIELD

[0001] The present invention relates generally to wireless communication networks, and in particular to a method and apparatus allowing a NF to retrieve a resource context established for a PDU session in a UPF. BACKGROUND

[0002] Wireless communication networks are ubiquitous in many parts of the world. As technology advances, the technical standards that define the operation of networks, and ensure interoperability of equipment from different vendors, evolve to both expand the networks’ capacity and sophistication, and to address new use cases. The Third Generation Partnership Project (3GPP) is a standards body that defines and promulgates technical standards for the operation of wireless cellular networks. Incremental advances are defined in numbered releases (e.g., Rel.16, Rel.17, etc.), and major advances are referred to as numbered generations. The Fourth Generation (4G), also known as Long Term Evolution (LTE) is widely deployed, and the Fifth Generation (5G) is in development.

[0003] Many aspects of 5G core network functionality are defined in 3GPP Technical Specifications (TS), including 3GPP TS 23.502 v18.0.0, “Procedures for the 5G System (5GS),” and 3GPP TS 29.564 v17.2.0, “User Plane Function Services,” as well as a recent revision, S2-230139323.502 CR3666R1 (Rel-18, 'B'), “Support of NAT exposure in 23.502 according to the conclusion in UPEAS,” the disclosures of all of which are incorporated by reference herein in their entireties.

[0004] In particular, the process by which an Application Function (AF) retrieves a specific User Equipment (UE) identification is described in TS 23.502 § 4.15.10, and is described below, with reference to Figure 1.

[0005] 1. AF requests to retrieve UE ID via the Nnef_UEId_Get service operation. The request message shall include UE address (IP address or MAC address) and AF Identifier, it may include, Port Number associated with the IP address, MTC Provider Information, Application Port ID, IP domain. The MTC Provider Information identifies the MTC Service Provider and / or MTC Application. If available, the AF may also provide the corresponding DNN and / or S-NSSAI.

[0006] NOTE 2: The MTC Provider Information can be used by any type of Service Providers (MTC or non- MTC) or Corporate or External Parties for, e.g. to distinguish their different customers.

[0007] NOTE 3: The combination of IP address and Port Number can be used by 5GC to derive the UE address if the UE is behind a NAT, see steps 3-6 below.NOTE 4: The Application Port ID is as defined in Nnef_Trigger_Delivery.

[0008] NOTE 5: The NEF can validate the provided MTC Provider Information and override it to a NEF selected MTC Provider Information based on configuration. How the NEF determines the MTC Provider Information, if not present, is left to implementation (e.g., based on the requesting AF).Applicant’s Ref. P107728WO01

[0009] 2. The NEF authorizes the AF request. If the authorization is not granted, the NEF replies to the AF with a Result value indicating authorization failure; otherwise the NEF proceeds with the following steps. The NEF determines corresponding DNN and / or S-NSSAI information: this may have been provided by the AF or is determined by the NEF based on the requesting AF Identifier, MTC Provider Information.

[0010] If the NEF has received a Port Number in step 1, based on configuration, the NEF may recognize the address received is a public IP address different from the actual UE IP address (private IP address), i.e., the UE is behind a NAT. If so, the NEF performs steps 3 to 6. Otherwise, steps 3 to 6 are skipped.

[0011] 3. The NEF uses the Nnrf_NFDiscovery service operation to obtain the UPF address of the UPF hosting the UE (public) IP address. The request includes the UE (public) IP address. The NEF may also include the DNN and S-NSSAI associated with the AF ID, as well as the IP domain.

[0012] 4. The NRF responds with a Nnrf_NFDiscovery response message including the UPF address of the UPF hosting the UE (public) IP address.

[0013] 5. The NEF uses the Nupf_GetPrivateUEIP_Get service operation to request UE’s (private) IP address from the UPF. The request includes the UE (public) IP address and Port Number, and optionally DNN and S- NSSAI associated with the AF ID.

[0014] 6. The UPF responds with the Nupf_GetPrivateUEIP_Get response message including UE’s IP address and the IP domain. If the UPF has applied a NAT functionality, the UE’s IP address returned by the UPF is the private UE IP address. If IP domain of UE private IP address is returned from UPF, it always takes precedence regardless of whether the IP domain information also provided by AF when it invokes Nnef_UEId_Get service operation.

[0015] 7-8. The NEF uses the Nbsf_Management_Discovery service operation with UE address and IP domain and / or DNN and / or S-NSSAI to retrieve the session binding information of the UE. If no SUPI is received in the session binding information from the BSF, the NEF replies to the AF with a Result value indicating that the UE ID is not available.

[0016] 9. The NEF interacts with UDM to retrieve the AF specific UE Identifier via the Nudm_SDM_Get service operation. The request message includes SUPI and at least one of Application Port ID, MTC Provider Information or AF Identifier.

[0017] 10. The UDM responds to the NEF with an AF specific UE Identifier represented as an External Identifier for the UE which is uniquely associated with the Application Port ID, MTC provider Information and / or AF Identifier.

[0018] 11. The NEF further responds to the AF with the information (including the AF specific UE Identifier represented as an External Identifier) received from the UDM. SUMMARY

[0019] Currently, there exist certain challenges.

[0020] As specified in the above-referenced revision, CR 23.502 - 3666 (S2-2301393), a new UPF service " Nupf_GetPrivateUEIPaddr" has been introduced to enable a NF consumer, e.g. a NEF, after discovery of theApplicant’s Ref. P107728WO01 serving UPF for a given NATed UE IP Address, to use it with the NATed public IP address (together with the source Port) to retrieve UE's PDU Session IP address, which is likely a private address, optionally together with the associated IP domain.

[0021] This new service is only limited to get the UE private IP address and IP domain by Public IP address and port.

[0022] 5.2.26.3 Nupf_Nupf_GetPrivateUEIPaddr service

[0023] 5.2.26.3.1 General

[0024] This service provides the UE IP address translation information (UE private IP address and IP domain).

[0025] 5.2.26.3.2 Nupf_GetPrivateUEIPaddr_Get service operation

[0026] Service operation name: Nupf_GetPrivateUEIPaddr_Get.

[0027] Description: NF service consumer gets the UE private IP address and IP domain.

[0028] Inputs, Required: Public IP address and port.

[0029] The Public IP address and port uniquely identifies the UE IP address behind a NAT

[0030] Inputs, Optional: None.

[0031] Outputs, Required: UE private IP address

[0032] Outputs, Optional: IP domain of UE private IP address

[0033] Certain aspects of the disclosure and their embodiments may provide solutions to these or other challenges. Embodiments described herein propose a mechanism to enable a NF service consumer of a UPF service (Nupf_GetPrivateUEIPaddr), e.g., a NEF, to retrieve a resource context established for a PDU session in the UPF, using a key which is able to uniquely identify the resource context in the UPF, e.g. • the NATed UE IP Address (together with the source port number (when Port Address Translation is used), or • the PDU Session IP Address o which can be a public IP address or o a private IP address {when it is a Private IP address, it shall be used together with DNN / S- NSSAI, and a IP domain [if the same private IP address (pertaining to a different IP domain) is used by another PDU session for the same DNN / S-NSSAI in the same UPF or different UPFs]}, • UeIpInfo identifier, which is uniquely identifying a resource context for a PDU session in the UPF, this can be set to “UP F-SEID” which is used to uniquely identify a PFCP session (for a PDU session) where such resource context is preferably called “UeIpInfo”, it shall support at least “GET” http method. BRIEF DESCRIPTION OF THE DRAWINGS The disclosure itself, the preferable mode of use and further objectives are best understood by reference to the following detailed description of the embodiments when read in conjunction with the accompanying drawings, in which:Applicant’s Ref. P107728WO01 Fig.1 is a signaling diagram illustrating an embodiment of the present disclosure; DETAILED DESCRIPTION

[0034] In particular, a new Data Type “UeIpInfo” relates to the resource context established for a given PDU session in the UPF. A NF consumer, e.g., a NEF, can retrieve the UEIpInfo for a PDU session by querying with the NATed UE's public IP address and an optional Port number or UE's private IP Address and IP domain.

[0035] The “UeIpInfo” includes at least following properties related to a PDU session in the UPF: 6.x.6.2.2 Type: UeIpInfo Table 6.x.6.2.2-1: Definition of type UeIpInfo Attribute name Data type P Cardinality Description UeIpInfoId string O 0..1 Identifier of a UeIpInfo for a PDU session. When present, the UeIpInfoId shall be encoded as a string of 8 hexadecimal characters (i.e., 64 bits). Pattern: '^[A-Fa-f0-9]{8}$' It can set to “UP F-SEID“ allocated by the UPF during establishment of PFCP session for a PDU session. (See 29.244-v18.0.1, clause 7.5.3.1) privateIpv4Address Ipv4Address O 0..1 This IE shall contain the Private IPv4 IP address. ipDomain string O 0..1 The IPv4 address domain of the UE when a private IPv4 address is allocated for a PDU session for a DNN / S-NSSAI and the private IPv4 address may be reused within the DNN / S-NSSAI. privateIpv6Prefix Ipv6Prefix O 0..1 This IE shall contain the Private IPv6 Prefix. NatedIpv4Address Ipv4Address O 0..1 This IE shall contain NATed IPv4 IP address or a public PDU session IPv4 address. NatedIpv6Prefix Ipv6Prefix O 0..1 This IE shall contain NATed IPv6 Prefix or a public PDU session IPv6 prefix. portNumber Uint16 O 0..1 The port number for the source UDP or TCP port when the Port Address Translation is used. dnn Dnn O 0..1 This IE may be present to contain the DNN to which the PDU Session pertain. snssai Snssai O 0..1 This IE may be present to contain the S-NSSAI to which the PDU Session pertain. supi Supi O 0..1 This IE may be present to contain the SUPI of the UE if it is available in the UPF. pei Pei O 0..1 This IE may be present to contain the PEI of the UE if it is available in the UPF. gpsi Gpsi O 0..1 When present, this attribute indicates the GPSI of the UE if it is available in the UPF. ATSSS Control ATSSS Control O 0..1 It may be present if the PDU session is Multi-access Parameters Parameters PDU session. When present, it shall contain Base64-encoded characters, encoding the ATSSS Control Parameters in the PFCP Session Establishment ResponseApplicant’s Ref. P107728WO01 message, as specified in Table 7.5.3.7-1 of 3GPP TS 29.244 [xx] (starting from octet 5). Created Bridge Info for Created Bridge O 0..1 It may be present if the PDU session is to support TSC Info for TSC time sensitive communication. When present, it shall contain Base64-encoded characters, encoding the Created Bridge Info for TSC in the PFCP Session Establishment Response message, as specified in Table 7.5.3.6-1 of 3GPP TS 29.244 [xx] (starting from octet 5). MBS Session N4 MBS Session N4 O 0..1 It may be present if UE uses the PDU session to Information Information receive MBS session data traffic e.g. when NG-RAN doesn’t support multicast over air. When present, it shall contain Base64-encoded characters, encoding the MBS Session N4 Information in the PFCP Session Establishment Response message, as specified in Table 7.5.3.1-5 of 3GPP TS 29.244 [xx] (starting from octet 5). Created L2TP Session Created L2TP O 0..1 It may be present if the PDU session is using Layer Session 2 tunnel protocol to access the Data network. When present, it shall contain Base64-encoded characters, encoding the Created L2TP Session in the PFCP Session Establishment Response message, as specified in Table 7.5.3.1-3 of 3GPP TS 29.244 [xx] (starting from octet 5). RDS configuration boolean O 0..1 it indicates whether the Reliable Data Service is information applied for the PDU session. True: applied False: not applied NOTE: The UPF shall find the matched UeIpInfo which contains either the NatedIpv4Address or privateIpv4Address matching the ue-ipv4-address in query, or the NatedIpv6Prefix or the privateIpv6Prefix matching the ue-ipv6-prefix in query. * * * * First change * * * * 3GPP TS 29.564 v17.2.0 5.1 Introduction The UPF offers the following services via the Nupf interface: - Nupf_EventExposure Service - Nupf_GetPrivateUEIPaddr Service Table 5.1-1 summarizes the corresponding APIs defined for this specification. Table 5.1-1: API Descriptions Service Name Clau Description OpenAPI Specification apiNa Anne se File me x Nupf_EventExposure 6.1 UPF Event TS29564_Nupf_EE.ya nupf- A.2 Exposure ml ee ServiceApplicant’s Ref. P107728WO01 Nupf_GetPrivateUEI 6.2 UPF TS29564_Nupf_GUEIP nupf- A.3 Paddr GetPrivateUEIP .yaml gueip addr Service * * * * Next change * * * * 5.x Nupf_GetPrivateUEIPaddr Service 5.x.1 Service Description The Nupf_GetPrivateUEIPaddr Service enables the UPF to provide the UE IP address information of a PDU session, e.g. to provide the (private) UE IP address when being queried with a NATed UE IP Address, to the service consumers, e.g. a NEF. Table 5.x.1-1 lists the service operations that are supported by the Nupf_GetPrivateUEIPaddr service. Table 5.x.1-1: Service operations supported by the Nupf_GetPrivateUEIPaddr service Operation Example Service Operations Description Semantics Consumers retrieve the UE IP address information of a PDU session, to get Request / Get NEF e.g., UE's private IP address and Response optionally the associated IP domain. * * * * Next change * * * * 5.x.2 Service Operations 5.x.2.1 Introduction See Table 5.x.1-1 for an overview of the service operations supported by the Nupf_GetPrivateUEIPaddr service. * * * * Next change * * * * 5.x.2.2 Get 5.x.2.2.1 General The Get service operation are used in the following procedures: - AF specific UE ID retrieval as specified in clause 4.15.10 of 3GPP TS 23.502 [3]Applicant’s Ref. P107728WO01 This service operation is executed by querying the "ue-ip-info" resource. The request is sent to the UPF hosting the IP address (and the port number) in query. NF Service Consumer UPF 1. GET ... / ue-ip-info?<query parameters> 2a.200 OK (UeIpInfo) 2b.4xx / 5xx (ProblemDetails) or 3xx Figure 5.x.2.2.1-1: Retrieval of UE IP Info for a PDU session 1. The NF Service Consumer shall send an HTTP GET request to the resource URI "ue-ip- info" collection resource. The input filter criteria for the discovery request shall be included in query parameters, e.g. the UE (public) IP address and Port Number, and optionally DNN and S-NSSAI provided by the AF. 2a. On success, "200 OK" shall be returned. The response body shall include a UeIpInfo object which attributes matching the query parameters included in the request message. 2b. On failure, one of the HTTP status code listed in Table 6.x.3.2.3.1-3 shall be returned. For a 4xx / 5xx response, the message body may contain a ProblemDetails structure with the "cause" attribute set to one of the application errors listed in Table 6.x.3.3.3.2-2, where applicable. On redirection, "307 Temporary Redirect" or "308 Permanent Redirect" shall be returned. A RedirectResponse IE shall be included in the payload body of POST response. * * * * Next change * * * * 6.x Nupf_GetPrivateUEIPaddr Service API 6.x.1 Introduction The Nupf_GetPrivateUEIPaddr service shall use the Nupf_GetPrivateUEIPaddr API. The API URI of the Nupf_GetPrivateUEIPaddr Service API shall be: {apiRoot} / <apiName> / <apiVersion> The request URI used in HTTP requests from the NF service consumer towards the NF service producer shall have the Resource URI structure defined in clause 4.4.1 of 3GPP TS 29.501 [5], i.e.: {apiRoot} / <apiName> / <apiVersion> / <apiSpecificResourceUriPart> with the following components: - The {apiRoot} shall be set as described in 3GPP TS 29.501 [5].Applicant’s Ref. P107728WO01 - The <apiName> shall be "nupf_gueip". - The <apiVersion> shall be "v1". - The <apiSpecificResourceUriPart> shall be set as described in clause 5.3. * * * * Next change * * * * 6.x.2 Usage of HTTP 6.x.2.1 General HTTP / 2, IETF RFC 7540

[0011] , shall be used as specified in clause 5 of 3GPP TS 29.500 [4]. HTTP / 2 shall be transported as specified in clause 5.3 of 3GPP TS 29.500 [4]. The OpenAPI [6] specification of HTTP messages and content bodies for the Nupf_GetPrivateUEIPaddr API is contained in Annex A. 6.x.2.2 HTTP standard headers 6.x.2.2.1 General See clause 5.2.2 of 3GPP TS 29.500 [4] for the usage of HTTP standard headers. 6.x.2.2.2 Content type JSON, IETF RFC 8259

[0012] , shall be used as content type of the HTTP bodies specified in the present specification as specified in clause 5.4 of 3GPP TS 29.500 [4]. The use of the JSON format shall be signalled by the content type "application / json". "Problem Details" JSON object shall be used to indicate additional details of the error in a HTTP response body and shall be signalled by the content type "application / problem+json", as defined in IETF RFC 7807

[0013] . 6.x.2.3 HTTP custom headers The mandatory HTTP custom header fields specified in clause 5.2.3.2 of 3GPP TS 29.500 [4] shall be supported, and the optional HTTP custom header fields specified in clause 5.2.3.3 of 3GPP TS 29.500 [4] may be supported. * * * * Next change * * * * 6.x.3 Resources 6.1.3.1 OverviewApplicant’s Ref. P107728WO01 {apiRoot} / nupf-gueip / <apiVersion> / ue-ip-info Figure 6.x.3.1-1: Resource URI structure of the Nupf_GetPrivateUEIPaddr API Table 6.x.3.1-1 provides an overview of the resources and applicable HTTP methods. Table 6.1.3.1-1: Resources and methods overview HTTP method Resource Resource URI or Description name custom operation UE IP / ue-ip-info GET Nupf_GetPrivateUEIPaddr_Get Address Info collection * * * * Next change * * * * 6.x.3.2 Resource: UE IP Address Info 6.x.3.2.1 Description This resource represents the collection of the UE IP Address Info for all PDU session served by the UPF, where each UE IP Address Info for a given PDU session includes a (private) PDU Session IP address and the optional associated IP domain, the corresponding NATed IP address and the optional Port Number (when the Network Address Translation is used), the DNN and the S-NSSAI to which the PDU session pertain when such information are available in the UPF. This resource is modelled with the Collection resource archetype (see clause C.2 of 3GPP TS 29.501 [5]).Applicant’s Ref. P107728WO01 6.x.3.2.2 Resource Definition Resource URI: {apiRoot} / nupf_gueip / <apiVersion> / ue-ip-info This resource shall support the resource URI variables defined in table 6.x.3.2.2-1. Table 6.x.3.2.2-1: Resource URI variables for this resource Name Definition apiRoot See clause 6.1.1 apiVersion See clause 6.1.1 6.x.3.2.3 Resource Standard Methods 6.x.3.2.3.1 GET This operation retrieves the UE IP Info for a PDU session which contains the UE's (private) PDU Session IP address by querying with the NATed UE's public IP address and an optional Port number. This method shall support the URI query parameters specified in table 6.x.3.2.3.1-1. Table 6.X.3.2.3.1-1: URI query parameters supported by the GET method on this resource Name Data type P Cardinali Applicability Description ty ue-ipv4- Ipv4Addr C 0..1 The UE's IPv4 address address ue-ipv6- Ipv6Prefix C 0..1 The UE's IPv6 Prefix prefix port-number integer C 0..1 The Source UDP or TCP Port dnn Dnn O 0..1 The DNN to which the PDU session pertain snssai Snssai O 0..1 The S-NSSAI to which the PDU session pertain This method shall support the request data structures specified in table 6.x.3.2.3.1-2 and the response data structures and response codes specified in table 6.x.3.2.3.1-3. Table 6.x.3.2.3.1-2: Data structures supported by the GET Request Body on this resource Data type P Cardinalit Description yApplicant’s Ref. P107728WO01 n / a Table 6.x.3.2.3.1-3: Data structures supported by the GET Response Body on this resource Data type P Cardinalit Response Description y codes UeIpInfo M 1 200 OK The response body contains a UeIpInfo for a PDU session which contains attributes that are matching the querying parameter. RedirectResp O 0..1 307 Temporary redirection. The response shall onse Tempora include a Location header field containing a ry different URI, or the same URI if a request is Redirect redirected to the same target resource via a different SCP. RedirectResp O 0..1 308 Permanent redirection. The response shall include onse Permane a Location header field containing a different nt URI, or the same URI if a request is redirected to Redirect the same target resource via a different SCP. ProblemDetai O 0..1 400 Bad The response body contains the error reason of ls Request the request message. ProblemDetai O 0..1 404 Not The "cause" attribute may be used to indicate the ls Found following application error: - NO_UE_IP_INFO_FOUND See table 6.x.7.3-1 for the description of this error. NOTE: The manadatory HTTP error status code for the GET method listed in Table 5.2.7.1-1 of 3GPP TS 29.500 [4] also apply, with response body containing an object of ProblemDetails data type (see clause 5.2.7 of 3GPP TS 29.500 [4]). Table 6.x.3.2.3.1-4: Headers supported by the 307 Response Code on this resource Name Data type P Cardinali DescriptionApplicant’s Ref. P107728WO01 ty Location string M 1 An alternative URI of the resource located on an alternative service instance. It is implementation specific how the alternative URI is determined. Or the same URI, if a request is redirected to the same target resource via a different SCP. 3gpp-Sbi- string O 0..1 Identifier of the target NF (service) instance ID Target-Nf-Id towards which the request is redirected Table 6.x.3.2.3.1-5: Headers supported by the 308 Response Code on this resource Name Data type P Cardinali Description ty Location string M 1 An alternative URI of the resource located on an alternative service instance. It is implementation specific how the alternative URI is determined. Or the same URI, if a request is redirected to the same target resource via a different SCP. 3gpp-Sbi- string O 0..1 Identifier of the target NF (service) instance ID Target-Nf-Id towards which the request is redirected 6.x.3.2.4 Resource Custom Operations None. * * * * Next change * * * * 6.x.5 Notifications 6.x.5.1 General Notifications shall comply to clause 6.2 of 3GPP TS 29.500 [4] and clause 4.6.2.3 of 3GPP TS 29.501 [5]. * * * * Next change * * * *Applicant’s Ref. P107728WO01 6.x.6 Data Model 6.x.6.1 General This clause specifies the application data model supported by the API. Table 6.x.6.1-1 specifies the data types defined for the Nupf_GetPrivateUEIPaddr service based interface protocol. Table 6.1.6.1-1: Nucmf_UECapabilityManagement specific Data Types Data type Clause Description Applicability defined UeIpInfo 6.1.6.2.2 A UeIpInfo for a PDU session Table 6.x.6.1-2 specifies data types re-used by the Nupf_GetPrivateUEIPaddr service based interface protocol from other specifications, including a reference to their respective specifications and when needed, a short description of their use within the N<NF> service based interface. Table 6.x.6.1-2: Nupf_GetPrivateUEIPaddr re-used Data Types Data type Reference Comments Applicability Dnn 3GPP TS 29.571

[0016] DNN Snssai 3GPP TS 29.571

[0016] S-NSSAI Ipv4Addr 3GPP TS 29.571

[0016] IPv4 address Ipv6Prefix 3GPP TS 29.571

[0016] IPv6 address prefix Gpsi 3GPP TS 29.571

[0016] GPSI Supi 3GPP TS 29.571

[0016] SUPI Pei 3GPP TS 29.571

[0016] PEI * * * * Next change * * * * 6.x.6.2 Structured data types 6.x.6.2.1 Introduction This clause defines the structures to be used in resource representations.Applicant’s Ref. P107728WO01 6.x.6.2.2 Type: UeIpInfo Table 6.x.6.2.2-1: Definition of type UeIpInfo Attribute name Data type P Cardinalit Description y UeIpInfoId string O 0..1 Identifier of a UeIpInfo for a PDU session. When present, the UeIpInfoId shall be encoded as a string of 8 hexadecimal characters (i.e.64 bits). Pattern: '^[A-Fa-f0-9]{8}$' privateIpv4Address Ipv4Address O 0..1 This IE shall contain the Private IPv4 IP address. ipDomain string O 0..1 The IPv4 address domain of the UE privateIpv6Prefix Ipv4Address O 0..1 This IE shall contain the Private IPv6 Prefix. NatedIpv4Address Ipv4Address O 0..1 This IE shall contain NATed IPv4 IP address or a public PDU session IPv4 address. NatedIpv6Prefix Ipv6Prefix O 0..1 This IE shall contain NATed IPv6 Prefix or a public PDU session IPv6 prefix. portNumber Uint16 O 0..1 The port number for the source UDP or TCP port when the Port Address Translation is used. dnn Dnn O 0..1 This IE may be present to contain the DNN to which the PDU Session pertain. snssai Snssai O 0..1 This IE may be present to contain the S-Applicant’s Ref. P107728WO01 NSSAI to which the PDU Session pertain. supi Supi O 0..1 This IE may be present to contain the SUPI of the UE if it is available in the UPF. pei Pei O 0..1 This IE may be present to contain the PEI of the UE if it is available in the UPF. gpsi Gpsi O 0..1 When present, this attribute indicates the GPSI of the UE if it is available in the UPF. NOTE: The UPF shall find the matched UeIpInfo which contains either the NatedIpv4Address or privateIpv4Address matching the ue-ipv4-address in query, or the NatedIpv6Prefix or the privateIpv6Prefix matching the ue-ipv6-prefix in query. * * * * Next change * * * * A.3 Nupf_GetPrivateUEIPaddr API openapi: 3.0.0 info: version: '1.0.0-alpha.1' title: 'UPF GET Private UE IP address Service' description: | Nupf_GetPrivateUEIPaddr Service. © 2023, 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). All rights reserved. externalDocs: description: 3GPP TS 29.564 V18.0.0; 5G System; Network Function Repository Services; Stage 3 url: 'https: / / www.3gpp.org / ftp / Specs / archive / 29_series / 29.565 / ' servers: - url: '{apiRoot} / nupf-gueip / v1'Applicant’s Ref. P107728WO01 variables: apiRoot: default: https: / / example.com description: apiRoot as defined in clause 4.4 of 3GPP TS 29.501 security: - {} - oAuth2ClientCredentials: - nupf-gueip - oAuth2ClientCredentials: - nupf-gueip paths: / ue-ip-info: get: summary: Search UeIpInfo for a PDU session from a collection of UeIpInfo operationId: SearchUeIpInfo tags: - UE IP Info (Store) parameters: - name: snssai in: query description: Slice to which the PDU session pertain schema: $ref: 'TS29571_CommonData.yaml# / components / schemas / Snssai' - name: dnn in: query description: Dnn to which the PDU session pertain schema: $ref: 'TS29571_CommonData.yaml# / components / schemas / Dnn' - name: ue-ipv4-address in: query description: IPv4 address of the UE schema:Applicant’s Ref. P107728WO01 $ref: 'TS29571_CommonData.yaml# / components / schemas / Ipv4Addr' - name: ue-ipv6-prefix in: query description: IPv6 prefix of the UE schema: $ref: 'TS29571_CommonData.yaml# / components / schemas / Ipv6Prefix' - name: port-number in: query description: the source UDP or TCP port associated with the public address schema: type: integer minimum: 0 maximum: 65535 responses: '200': description: Expected response to a valid request content: application / json: schema: $ref: '# / components / schemas / UeIpInfo '307': description: Temporary Redirect content: application / json: schema: $ref: 'TS29571_CommonData.yaml# / components / schemas / RedirectResponse' headers: Location: description: The URI pointing to the resource located on the redirect target UPF required: true schema: type: string '308':Applicant’s Ref. P107728WO01 description: Permanent Redirect content: application / json: schema: $ref: 'TS29571_CommonData.yaml# / components / schemas / RedirectResponse' headers: Location: description: The URI pointing to the resource located on the redirect target UPF required: true schema: type: string '400': $ref: 'TS29571_CommonData.yaml# / components / responses / 400' '401': $ref: 'TS29571_CommonData.yaml# / components / responses / 401' '403': $ref: 'TS29571_CommonData.yaml# / components / responses / 403' '404': $ref: 'TS29571_CommonData.yaml# / components / responses / 404' '406': $ref: 'TS29571_CommonData.yaml# / components / responses / 406' '411': $ref: 'TS29571_CommonData.yaml# / components / responses / 411' '413': $ref: 'TS29571_CommonData.yaml# / components / responses / 413' '415': $ref: 'TS29571_CommonData.yaml# / components / responses / 415' '429': $ref: 'TS29571_CommonData.yaml# / components / responses / 429' '500': $ref: 'TS29571_CommonData.yaml# / components / responses / 500' '501': $ref: 'TS29571_CommonData.yaml# / components / responses / 501' '503':Applicant’s Ref. P107728WO01 $ref: 'TS29571_CommonData.yaml# / components / responses / 503' default: $ref: 'TS29571_CommonData.yaml# / components / responses / default' components: securitySchemes: oAuth2ClientCredentials: type: oauth2 flows: clientCredentials: tokenUrl: '{nrfApiRoot} / oauth2 / token' scopes: nupf-gueip: Access to the Nupf_GetPrivateUEIPaddr API schemas: UeIpInfo: description: a UE IP Address Info for a PDU session type: object properties: ueIpInfoId: type: string pattern: '^[A-Fa-f0-9]{2}$' ueIpv4Addr: $ref: 'TS29571_CommonData.yaml# / components / schemas / Ipv4Addr' ueIpv6Prefix: $ref: 'TS29571_CommonData.yaml# / components / schemas / Ipv6Prefix' dnn: $ref: 'TS29571_CommonData.yaml# / components / schemas / Dnn' snssai: $ref: 'TS29571_CommonData.yaml# / components / schemas / Snssai' supi: $ref: 'TS29571_CommonData.yaml# / components / schemas / Supi' gpsi: $ref: 'TS29571_CommonData.yaml# / components / schemas / Gpsi'Applicant’s Ref. P107728WO01 pei: $ref: 'TS29571_CommonData.yaml# / components / schemas / Pei' * * * * End of changes * * * * 6.1.7 Error Handling 6.1.7.1 General For the Nupf_GetPrivateUEIPaddr API, HTTP error responses shall be supported as specified in clause 4.8 of 3GPP TS 29.501 [5]. Protocol errors and application errors specified in table 5.2.7.2-1 of 3GPP TS 29.500 [4] shall be supported for an HTTP method if the corresponding HTTP status codes are specified as mandatory for that HTTP method in table 5.2.7.1-1 of 3GPP TS 29.500 [4]. In addition, the requirements in the following clauses are applicable for the Nupf_GetPrivateUEIPaddr API. 6.1.7.2 Protocol Errors No specific procedures for the Nupf_GetPrivateUEIPaddr service are specified. 6.1.7.3 Application Errors The application errors defined for the Nupf_GetPrivateUEIPaddr service are listed in Table 6.1.7.3-1. Table 6.1.7.3-1: Application errors Application Error HTTP status Description code NO_UE_IP_INFO_FOUND 404 There is no dictionary entry matching the UE Radio Capability ID in query. * * * * Next change * * * * 6.1.8 Feature negotiation The optional features in table 6.1.8-1 are defined for the Nupf_GetPrivateUEIPaddr API. They shall be negotiated using the extensibility mechanism defined in clause 6.6 of 3GPP TS 29.500 [4]. Table 6.1.8-1: Supported Features Feature Feature Name M / O Description numberApplicant’s Ref. P107728WO01 * * * * Next change * * * * 6.1.9 Security As indicated in 3GPP TS 33.501 [8] and 3GPP TS 29.500 [4], the access to the Nupf_GetPrivateUEIPaddr API may be authorized by means of the OAuth2 protocol (see IETF RFC 6749 [9]), based on local configuration, using the "Client Credentials" authorization grant, where the NRF (see 3GPP TS 29.510

[0010] ) plays the role of the authorization server. If OAuth2 is used, an NF Service Consumer, prior to consuming services offered by the Nupf_GetPrivateUEIPaddr API, shall obtain a "token" from the authorization server, by invoking the Access Token Request service, as described in 3GPP TS 29.510

[0010] , clause 5.4.2.2. NOTE: When multiple NRFs are deployed in a network, the NRF used as authorization server is the same NRF that the NF Service Consumer used for discovering the Nupf_GetPrivateUEIPaddr service. The Nupf_GetPrivateUEIPaddr API defines a single scope "nupf_gueip" for the entire service, and it does not define any additional scopes at resource or operation level. * * * * End of change * * * *

[0036] Although the computing devices described herein (e.g., UEs, network nodes, hosts) may include the illustrated combination of hardware components, other embodiments may comprise computing devices with different combinations of components. It is to be understood that these computing devices may comprise any suitable combination of hardware and / or software needed to perform the tasks, features, functions, and methods disclosed herein. Determining, calculating, obtaining or similar operations described herein may be performed by processing circuitry, which may process information by, for example, converting the obtained information into other information, comparing the obtained information, or converted information to information stored in the network node, and / or performing one or more operations based on the obtained information or converted information, and as a result of said processing making a determination. Moreover, while components are depicted as single boxes located within a larger box, or nested within multiple boxes, in practice, computing devices may comprise multiple different physical components that make up a single illustrated component, and functionality may be partitioned between separate components. For example, a communication interface may be configured to include any of the components described herein, and / or the functionality of the components may be partitioned between the processing circuitry and the communication interface. In another example, non-computationally intensive functions of any of suchApplicant’s Ref. P107728WO01 components may be implemented in software or firmware and computationally intensive functions may be implemented in hardware.

[0037] In certain embodiments, some or all of the functionality described herein may be provided by processing circuitry executing instructions stored on in memory, which in certain embodiments may be a computer program product in the form of a non-transitory computer-readable storage medium. In alternative embodiments, some or all of the functionality may be provided by the processing circuitry without executing instructions stored on a separate or discrete device-readable storage medium, such as in a hard-wired manner. In any of those particular embodiments, whether executing instructions stored on a non-transitory computer-readable storage medium or not, the processing circuitry can be configured to perform the described functionality. The benefits provided by such functionality are not limited to the processing circuitry alone or to other components of the computing device, but are enjoyed by the computing device as a whole, and / or by end users and a wireless network generally.

[0038] Additional information may also be found in the document(s) provided in the Appendix.Applicant’s Ref. P107728WO01 EMBODIMENTS Some of the embodiments that have been described above may be summarized in the following manner: 1. A method, performed by a User Plane Function (UPF) in a wireless communication core network, of providing a resource context established for a Protocol Data Unit (PDU) session, comprising: receiving, from a Network Function (NF), a request for the resource context, the request including a key uniquely identifying the resource context; and providing to the NF the identified resource context. 2. The method of embodiment 1 wherein the key uniquely identifying the resource context is a Network Address Translated (NATed) User Equipment (UE) IP address. 3. The method of embodiment 2 wherein the key uniquely identifying the resource context further includes a source port number when Port Address Translation is used. 4. The method of embodiment 1 wherein the key uniquely identifying the resource context is a PDU Session IP Address. 5. The method of embodiment 4 wherein the PDU Session IP Address is a public IP address. 6. The method of embodiment 4 wherein the PDU Session IP Address is a private IP address, and wherein the key additionally includes a Data Network Name (DNN) and single Network Slice-Specific Association Information (S-NSSAI). 7. The method of embodiment 6 wherein, if the same private IP address, but pertaining to a different IP domain, is used by another PDU session for the same DNN / S-NSSAI in the same UPF or different UPFs, the key further includes an IP domain. 8. The method of embodiment 1 wherein the key uniquely identifying the resource context is a UeIpInfo identifier, which uniquely identifies a resource context for a PDU session in the UPF. 9. The method of embodiment 1, wherein the UeIpInfo identifier this is set to “UP F-SEID” which is used to uniquely identify a PFCP session for a PDU session. 10. The method of embodiment 8 wherein the UeIpInfo identifier has one or more of the following properties (e.g. an UeIpInfoId etc.) related to a PDU session in the UPF: Attribute name Data type P Cardinality Description UeIpInfoId string O 0..1 Identifier of a UeIpInfo for a PDU session.Applicant’s Ref. P107728WO01 When present, the UeIpInfoId shall be encoded as a string of 8 hexadecimal characters (i.e. 64 bits). Pattern: '^[A-Fa-f0-9]{8}$' It can set to “UP F-SEID“ allocated by the UPF during establishment of PFCP session for a PDU session. (See 29.244-v18.0.1, clause 7.5.3.1) privateIpv4Address Ipv4Address O 0..1 This IE shall contain the Private IPv4 IP address. ipDomain string O 0..1 The IPv4 address domain of the UE when a private IPv4 address is allocated for a PDU session for a DNN / S-NSSAI and the private IPv4 address may be reused within the DNN / S- NSSAI. privateIpv6Prefix Ipv6Prefix O 0..1 This IE shall contain the Private IPv6 Prefix. NatedIpv4Address Ipv4Address O 0..1 This IE shall contain NATed IPv4 IP address or a public PDU session IPv4 address. NatedIpv6Prefix Ipv6Prefix O 0..1 This IE shall contain NATed IPv6 Prefix or a public PDU session IPv6 prefix. portNumber Uint16 O 0..1 The port number for the source UDP or TCP port when the Port Address Translation is used. dnn Dnn O 0..1 This IE may be present to contain the DNN to which the PDU Session pertain. snssai Snssai O 0..1 This IE may be present to contain the S-NSSAI to which the PDU Session pertain. supi Supi O 0..1 This IE may be present to contain the SUPI of the UE if it is available in the UPF. pei Pei O 0..1 This IE may be present to contain the PEI of the UE if it is available in the UPF. gpsi Gpsi O 0..1 When present, this attribute indicates the GPSI of the UE if it is available in the UPF. ATSSS Control ATSSS Control O 0..1 It may be present if the PDU session is Multi- Parameters Parameters access PDU session. When present, it shall contain Base64-encoded characters, encoding the ATSSS Control Parameters in the PFCP Session Establishment Response message, as specified in Table 7.5.3.7-1 of 3GPP TS 29.244 [xx] (starting from octet 5). Created Bridge Info Created Bridge O 0..1 It may be present if the PDU session is to for TSC Info for TSC support time sensitive communication.Applicant’s Ref. P107728WO01 When present, it shall contain Base64-encoded characters, encoding the Created Bridge Info for TSC in the PFCP Session Establishment Response message, as specified in Table 7.5.3.6-1 of 3GPP TS 29.244 [xx] (starting from octet 5). MBS Session N4 MBS Session O 0..1 It may be present if UE uses the PDU session Information N4 Information to receive MBS session data traffic e.g. when NG-RAN doesn’t support multicast over air. When present, it shall contain Base64-encoded characters, encoding the MBS Session N4 Information in the PFCP Session Establishment Response message, as specified in Table 7.5.3.1-5 of 3GPP TS 29.244 [xx] (starting from octet 5). Created L2TP Created L2TP O 0..1 It may be present if the PDU session is using Session Session Layer 2 tunnel protocol to access the Data network. When present, it shall contain Base64-encoded characters, encoding the Created L2TP Session in the PFCP Session Establishment Response message, as specified in Table 7.5.3.1-3 of 3GPP TS 29.244 [xx] (starting from octet 5). RDS configuration boolean O 0..1 it indicates whether the Reliable Data Service is information applied for the PDU session. True: applied False: not applied NOTE: The UPF shall find the matched UeIpInfo which contains either the NatedIpv4Address or privateIpv4Address matching the ue-ipv4-address in query, or the NatedIpv6Prefix or the privateIpv6Prefix matching the ue-ipv6-prefix in query. 11. A network node, operative in a wireless communication core, and implementing a User Plane Function (UPF), comprising: communication circuitry configured to communicate with other network nodes and Network Functions (NF); processing circuitry operatively connected to the communication circuitry, and configured to: receive, from a NF, a request for a resource context established for a Protocol Data Unit (PDU) session, the request including a key uniquely identifying the resource context; and providing to the NF the identified resource context. 12. The network node of embodiment 11 wherein the key uniquely identifying the resource context is a Network Address Translated (NATed) User Equipment (UE) IP address. 13. The network node of embodiment 12 wherein the key uniquely identifying the resource context furtherApplicant’s Ref. P107728WO01 includes a source port number when Port Address Translation is used. 14. The network node of embodiment 11 wherein the key uniquely identifying the resource context is a PDU Session IP Address. 15. The network node of embodiment 14 wherein the PDU Session IP Address is a public IP address. 16. The network node of embodiment 14 wherein the PDU Session IP Address is a private IP address, and wherein the key additionally includes a Data Network Name (DNN) and single Network Slice-Specific Association Information (S-NSSAI). 17. The network node of embodiment 16 wherein, if the same private IP address, but pertaining to a different IP domain, is used by another PDU session for the same DNN / S-NSSAI in the same UPF or different UPFs, the key further includes an IP domain. 18. The network node of embodiment 11 wherein the key uniquely identifying the resource context is a UeIpInfo identifier, which uniquely identifies a resource context for a PDU session in the UPF. 19. The network node of embodiment 11, wherein the UeIpInfo identifier this is set to “UP F-SEID” which is used to uniquely identify a PFCP session for a PDU session. 20. The network node of embodiment 18 wherein the UeIpInfo identifier has one or more of the following properties (e.g. an UeIpInfoId etc.) related to a PDU session in the UPF: Attribute name Data type P Cardinality Description UeIpInfoId string O 0..1 Identifier of a UeIpInfo for a PDU session. When present, the UeIpInfoId shall be encoded as a string of 8 hexadecimal characters (i.e.64 bits). Pattern: '^[A-Fa-f0-9]{8}$' It can set to “UP F-SEID“ allocated by the UPF during establishment of PFCP session for a PDU session. (See 29.244-v18.0.1, clause 7.5.3.1) privateIpv4Address Ipv4Address O 0..1 This IE shall contain the Private IPv4 IP address. ipDomain string O 0..1 The IPv4 address domain of the UE when a private IPv4 address is allocated for a PDU session for a DNN / S-NSSAI and the private IPv4 address may be reused within the DNN / S- NSSAI.Applicant’s Ref. P107728WO01 privateIpv6Prefix Ipv6Prefix O 0..1 This IE shall contain the Private IPv6 Prefix. NatedIpv4Address Ipv4Address O 0..1 This IE shall contain NATed IPv4 IP address or a public PDU session IPv4 address. NatedIpv6Prefix Ipv6Prefix O 0..1 This IE shall contain NATed IPv6 Prefix or a public PDU session IPv6 prefix. portNumber Uint16 O 0..1 The port number for the source UDP or TCP port when the Port Address Translation is used. dnn Dnn O 0..1 This IE may be present to contain the DNN to which the PDU Session pertain. snssai Snssai O 0..1 This IE may be present to contain the S-NSSAI to which the PDU Session pertain. supi Supi O 0..1 This IE may be present to contain the SUPI of the UE if it is available in the UPF. pei Pei O 0..1 This IE may be present to contain the PEI of the UE if it is available in the UPF. gpsi Gpsi O 0..1 When present, this attribute indicates the GPSI of the UE if it is available in the UPF. ATSSS Control ATSSS Control O 0..1 It may be present if the PDU session is Multi- Parameters Parameters access PDU session. When present, it shall contain Base64-encoded characters, encoding the ATSSS Control Parameters in the PFCP Session Establishment Response message, as specified in Table 7.5.3.7-1 of 3GPP TS 29.244 [xx] (starting from octet 5). Created Bridge Info Created Bridge O 0..1 It may be present if the PDU session is to for TSC Info for TSC support time sensitive communication. When present, it shall contain Base64-encoded characters, encoding the Created Bridge Info for TSC in the PFCP Session Establishment Response message, as specified in Table 7.5.3.6-1 of 3GPP TS 29.244 [xx] (starting from octet 5). MBS Session N4 MBS Session O 0..1 It may be present if UE uses the PDU session Information N4 Information to receive MBS session data traffic e.g. when NG-RAN doesn’t support multicast over air. When present, it shall contain Base64-encoded characters, encoding the MBS Session N4 Information in the PFCP Session Establishment Response message, as specified in Table 7.5.3.1-5 of 3GPP TS 29.244 [xx] (starting from octet 5). Created L2TP Created L2TP O 0..1 It may be present if the PDU session is using Session Session Layer 2 tunnel protocol to access the Data network.Applicant’s Ref. P107728WO01 When present, it shall contain Base64-encoded characters, encoding the Created L2TP Session in the PFCP Session Establishment Response message, as specified in Table 7.5.3.1-3 of 3GPP TS 29.244 [xx] (starting from octet 5). RDS configuration boolean O 0..1 it indicates whether the Reliable Data Service is information applied for the PDU session. True: applied False: not applied NOTE: The UPF shall find the matched UeIpInfo which contains either the NatedIpv4Address or privateIpv4Address matching the ue-ipv4-address in query, or the NatedIpv6Prefix or the privateIpv6Prefix matching the ue-ipv6-prefix in query.Applicant’s Ref. P107728WO01 ABBREVIATIONS AbbreviationExplanation5GC 5G Core Network AF Application Function BSF Binding Support Function DNN Data Network Name IP Internet Protocol MAC Media Access Control MTC Machine Type Communication NAT Network address translation NF Network Function NEF Network Exposure Function NRF Network Repository Function NW Network NWDAF Network Data Analytics Function PFCP Packet Forwarding Control Protocol S-NSSAI Single – Network Slice-Specific Assistance Information SMF Session Management Function SUPI Subscription Permanent Identifier UDM Unified Data Management UE User Equipment UPF User Plane Function

Claims

Applicant’s Ref. P107728WO01 CLAIMS What is claimed is:

1. A method, performed by a User Plane Function (UPF) in a wireless communication core network, of providing a resource context established for a Protocol Data Unit (PDU) session, comprising: receiving, from a Network Function (NF), a request for the resource context, the request including a key uniquely identifying the resource context; and providing to the NF the identified resource context.

2. The method of claim 1 wherein the key uniquely identifying the resource context is a Network Address Translated (NATed) User Equipment (UE) IP address.

3. The method of claim 2 wherein the key uniquely identifying the resource context further includes a source port number when Port Address Translation is used.

4. The method of claim 1 wherein the key uniquely identifying the resource context is a PDU Session IP Address.

5. The method of claim 4 wherein the PDU Session IP Address is a public IP address.

6. The method of claim 4 wherein the PDU Session IP Address is a private IP address, and wherein the key additionally includes a Data Network Name (DNN) and single Network Slice-Specific Association Information (S- NSSAI).

7. The method of claim 6 wherein, if the same private IP address, but pertaining to a different IP domain, is used by another PDU session for the same DNN / S-NSSAI in the same UPF or different UPFs, the key further includes an IP domain.

8. The method of claim 1 wherein the key uniquely identifying the resource context is a UeIpInfo identifier, which uniquely identifies a resource context for a PDU session in the UPF.

9. The method of claim 8, wherein the UeIpInfo identifier this is set to “UP F-SEID” which is used to uniquely identify a PFCP session for a PDU session.

10. A network node, operative in a wireless communication core, and implementing a User Plane Function (UPF), comprising:Applicant’s Ref. P107728WO01 communication circuitry configured to communicate with other network nodes and Network Functions (NF); processing circuitry operatively connected to the communication circuitry, and configured to: receive, from a NF, a request for a resource context established for a Protocol Data Unit (PDU) session, the request including a key uniquely identifying the resource context; and providing to the NF the identified resource context.

11. The network node of claim 10 wherein the key uniquely identifying the resource context is a Network Address Translated (NATed) User Equipment (UE) IP address.

12. The network node of claim 11 wherein the key uniquely identifying the resource context further includes a source port number when Port Address Translation is used.

13. The network node of claim 10 wherein the key uniquely identifying the resource context is a PDU Session IP Address.

14. The network node of claim 13 wherein the PDU Session IP Address is a public IP address.

15. The network node of claim 13 wherein the PDU Session IP Address is a private IP address, and wherein the key additionally includes a Data Network Name (DNN) and single Network Slice-Specific Association Information (S-NSSAI).

16. The network node of claim 15 wherein, if the same private IP address, but pertaining to a different IP domain, is used by another PDU session for the same DNN / S-NSSAI in the same UPF or different UPFs, the key further includes an IP domain.

17. The network node of claim 10 wherein the key uniquely identifying the resource context is a UeIpInfo identifier, which uniquely identifies a resource context for a PDU session in the UPF.

18. The network node of claim 17, wherein the UeIpInfo identifier this is set to “UP F-SEID” which is used to uniquely identify a PFCP session for a PDU session.

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