WO2019196030A1

WO2019196030A1 - Selecting non-3gpp access nodes to support ims services to 5g core networks

Info

Publication number: WO2019196030A1
Application number: PCT/CN2018/082672
Authority: WO
Inventors: Xingyue Zhou; Zhendong Li
Original assignee: ZTE Corp
Current assignee: ZTE Corp
Priority date: 2018-04-11
Filing date: 2018-04-11
Publication date: 2019-10-17
Anticipated expiration: 2020-10-11
Also published as: CN111512692A

Abstract

Disclosed are methods, systems and devices for selecting non-3GPP access nodes to support IMS services to 5G core networks. One example method for enabling identification of IMS support in a candidate non-3GPP node or network includes transmitting configuration information that includes an indicator of IMS (Internet Protocol (IP) Multimedia Subsystem) voice services support by an access node in a second network, where the indicator corresponds to an ability of the access node in the second network to support IMS voice services. Another method includes receiving configuration information comprising an indicator of IMS voice services support by an access node in a second network, and selectively accessing the IMS voice services in the second network through the access node based on the indicator.

Description

SELECTING NON-3GPP ACCESS NODES TO SUPPORT IMS SERVICES TO 5G CORE NETWORKS

TECHNICAL FIELD

This document is related to wireless communications.

BACKGROUND

Wireless communication technologies are moving the world toward an increasingly connected and networked society. The rapid growth of wireless communications and advances in technology has led to greater demand for capacity and connectivity. Other aspects, such as energy consumption, device cost, spectral efficiency, and latency are also important to meeting the needs of various communication scenarios. In comparison with the existing wireless networks, next generation systems and wireless communication techniques need to ensure that services available in different types of networks are consistently identified correctly.

SUMMARY

This document relates to methods, systems, and devices for selecting non-3GPP access nodes to support IMS (IP Multimedia Subsystem) services to 5G core networks. Using the disclosed technology, embodiments are able to identify which non-3GPP access nodes can support IMS voice when a UE is transferring from a 5G (e.g. New Radio (NR) ) implementation to a non-3GPP network.

In one exemplary aspect, a wireless communication method is disclosed. The method, which may be implemented at a network node (e.g. base station, eNB, gNB) , includes transmitting configuration information that include an indicator of IMS voice services support by an access node in a second network, where the indicator corresponds to an ability of the access node in the second network to support IMS voice services.

In another exemplary aspect, a wireless communication method is disclosed. The method, which may be implemented at a wireless terminal (e.g. user equipment (UE) ) , includes receiving configuration information comprising an indicator of IMS voice services support by an access node in a second network, and selectively accessing the IMS voice services in the second network through the access node based on the indicator, where the indicator corresponds to an ability of the access node in the second network to support IMS voice services.

In yet another exemplary aspect, the above-described methods are embodied in the form of processor-executable code and stored in a computer-readable program medium.

In yet another exemplary embodiment, a device that is configured or operable to perform the above-described methods is disclosed.

The above and other aspects and their implementations are described in greater detail in the drawings, the descriptions, and the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows an example of 5G system (5GS) architecture.

FIG. 2 shows an example of a non-3GPP network supporting 4G network access.

FIG. 3 shows an example of a non-3GPP and 5G network interworking.

FIG. 4 shows an example of a base station (BS) and user equipment (UE) in wireless communication, in accordance with some embodiments of the presently disclosed technology.

FIG. 5 shows an example of an evolved Packet Data Gateway (ePDG) identifier configuration structure for selecting non-3GPP access nodes to support IMS services to 5GS.

FIG. 6 shows an example of non-3GPP access node (N3AN) selection information structure for selecting non-3GPP access nodes to support IMS services to 5GS.

FIG. 7 shows an example of a trusted wireless local area network (WLAN) selection information structure for selecting non-3GPP access nodes to support IMS services to 5GS.

FIG. 8 shows an example of a wireless communication method for selecting non-3GPP access nodes to support IMS services to 5G core networks.

FIG. 9 shows an example of another wireless communication method for selecting non-3GPP access nodes to support IMS services to 5G core networks.

FIG. 10 is a block diagram representation of a portion of an apparatus, in accordance with some embodiments of the presently disclosed technology.

DETAILED DESCRIPTION

In current systems and implementations, when a UE wants to select a non-3GPP access node/network (e.g. ePDG, N3IWF, trusted non-3GPP access network) for IMS voice, the UE is not able to learn whether the non-3GPP access network supported IMS voice based on the available selection or configuration information.

The UE may only try to select another non-3GPP access node/network and initiate an attach/registration procedure via the non-3GPP access node/network. During the procedure, the UE learns whether the target network supports IMS voice by receiving an indicator from the network. If the network indicates that it is unable to support IMS voice, the UE typically detaches from the network and makes another non-3GPP access network selection.

5th generation mobile networks or 5th generation wireless systems, abbreviated 5G, are the proposed next telecommunications standards beyond the current 4G/IMT-Advanced standards. In some implementations, the 5G System (5GS) architecture may support data connectivity and services enabling deployments to use techniques such as e.g. Network Function Virtualization and Software Defined Networking. The 5G System architecture could leverage service-based interactions between Control Plane (CP) Network Functions where identified.

FIG. 1 shows an exemplary 5G System architecture, which may include the following main network functions (NF) :

·Authentication Server Function (AUSF)

·Core Access and Mobility Management Function (AMF)

·Data network (DN) , e.g. operator services, Internet access or 3rd party services

·Structured Data Storage network function (SDSF)

·Unstructured Data Storage network function (UDSF)

·Network Exposure Function (NEF)

·NF Repository Function (NRF)

·Policy Control function (PCF)

·Session Management Function (SMF)

·Unified Data Management (UDM)

·User Plane Function (UPF)

·Application Function (AF)

·User Equipment (UE)

·(Radio) Access Network ( (R) AN)

Non-3GPP access (e.g. WLAN access) is an important companion access infrastructure for mobile networks that can help mobile operators deal with the explosive rate of growth in network traffic. Non-3GPP access such can relieve the pressure on the mobile network and can offer fast indoor data connections.

FIG. 2 shows an example of a non-3GPP network supporting 4G network access. As shown therein, the 3GPP serving gateway, which may be managed by the HPLMN, can access the non-3GPP node in either a trusted or untrusted manner.

In 5G, the Core Network also supports the connectivity of the UE via standalone non-3GPP access networks, e.g. WLAN access, fixed wireline access network. FIG. 3 shows an example of a non-3GPP and 5G network interworking. As shown in FIG. 3, non-3GPP access networks to the 5G core network could be either trusted or untrusted, and depends on the related operator policies. For untrusted non-3GPP access network, it may be connected to the 5G Core Network via a Non-3GPP Interworking Function (N3IWF) . The N2 and N3 are used to connect trusted non-3GPP access or N3IWF to 5G Core Network as a control plane and a user plane reference point, respectively.

In some embodiments, non-3GPP access, especially WLAN access, is commonly used by the operators for providing IMS voice service to the UE as a way of complementing service. For example, in some areas (e.g. indoor) , the 3GPP Radio Access Network (RAN) does not support IMS voice or there may be no 3GPP radio coverage. In these cases, the UE is not able to use IMS service which leads to poor user experience. If the UE has an IP address via WiFi, the UE may use this IP address to make an IP connectivity with an ePDG which supports IMS voice service to obtain IMS voice service. This solution is typically referred to as Voice-over-WiFi (or “VoWiFi” ) .

In recent systems and implementations, the UE may be configured by HPLMN with following information for ePDG/N3IWF selection:

(1) ePDG identifier configuration, which contains the Fully Qualified Domain Name (FQDN) or IP address of the ePDG in the HPLMN;

(2) N3IWF identifier configuration, which contains the FQDN or IP address of the N3IWF in the HPLMN; and

(3) Non-3GPP access node (N3AN) selection information, which contains a prioritized list of PLMNs.

In some embodiments, each PLMN includes (i) a “Preference” parameter which indicates if ePDG or N3IWF is preferred in this PLMN and (ii) an FQDN parameter which indicates if the Tracking/Location Area Identity FQDN or the Operator Identifier FQDN should be used when discovering the address of an ePDG or N3IWF in this PLMN. The list of PLMNs shall include the HPLMN and shall include an “any PLMN” entry, which matches any PLMN the UE is connected to except the HPLMN.

In some embodiments, the ePDG identifier configuration and the N3IWF identifier configuration are optional parameters, while the N3AN selection information is required and shall include at least the HPLMN and the “any PLMN” entry.

Embodiments of the disclosed technology enable improved interworking between 5G and non-3GPP nodes/networks by providing the ability to identify whether the non-3GPP node (or network) supports IMS, which improves the user experience, and reduces the need to connect to non-3GPP nodes that do not have the required capabilities for that UE. Section headings are used in the present document to improve readability of the description and do not in any way limit the discussion or the embodiments to the respective sections only.

FIG. 4 shows an example of a wireless communication system that includes a BS 420 and one or more user equipment (UE) 411, 412 and 413. In some embodiments, the BS 420 may transmit configuration information (441, 442, 443) that includes an indicator that corresponds to the ability of a candidate non-3GPP nodes to support IMS voice. The UEs may then transmit control information (431, 432, 433) to the BS in order to subsequently connect with the non-3GPP node (or network) . The UE may be, for example, a smartphone, a tablet, a mobile computer, a machine to machine (M2M) device, an Internet of Things (IoT) device, and so on.

Example Embodiment One: ePDG/N3IWF Selection

For untrusted non-3GPP access, the information configured by the network to the UE for untrusted non-3GPP access node selection can include indication on whether the non-3GPP access node support IMS voice services.

Thus, if the UE determines the non-3GPP access node selection is required for IMS voice service, the UE is able to select a non-3GPP access node supporting IMS voice service based on the information (also referred to as “configuration information” ) .

In some embodiments, the information may include:

(1) ePDG identifier configuration include the indication about the ePDG IMS voice service support. FIG. 5 shows an example of an ePDG identifier configuration structure for selecting non-3GPP access nodes to support IMS services to 5G core networks;

(2) N3IWF identifier configuration include the indication about the N3IWF IMS voice service support; or

(3) Non-3GPP access node (N3AN) selection information contains the PLMN it includes a parameter which indicates a parameter which indicates if ePDG or N3IWF in this PLMN supporting IMS voice service. FIG. 6 shows an example of N3AN selection information structure for selecting non-3GPP access nodes to support IMS services to 5G core networks.

Example Embodiment Two: Trusted WLAN Access Network Selection

For trusted non-3GPP access, the information configured by the network to the UE for trusted non-3GPP access node selection can include indication on whether the trusted non-3GPP access node support IMS voice.

Thus, if the UE determines the trusted non-3GPP access node selection is required for IMS voice service, the UE is able to select a trusted non-3GPP access node supporting IMS voice service based on the information (also referred to as “configuration information” ) .

In some embodiments, the information may include:

(1) An indication of the WLAN access node identified by a service set identifier (SSID) , a homogeneous extended service set identifier (HESSID) , a basic service set identifier (BSSID) or any other identifiers that support IMS voice service or not. FIG. 7 shows an example of a trusted WLAN selection information structure for selecting non-3GPP access nodes to support IMS services to 5G core networks.

Example Methods for Non-3GPP Node/Network Selection

FIG. 8 shows an example of a wireless communication method 800, which may be implemented at a network node, for selecting non-3GPP access nodes to support IMS services to 5G core networks. The method 800 includes, at step 810, transmitting, from a network node in a first network, configuration information comprising an indicator of IMS voice services support by an access node in a second network. In some embodiments, the first network may be a 5G core network and the second network may be a non-3GPP access network. For example, the non-3GPP access network may be defined by an alternate standardization group (e.g. IEEE, WiMax) . In some embodiments, the indicator corresponds to an ability of the access node in the second network to support IMS voice services.

The method 800 may include determining whether the access node in the second network has the ability to support IMS voice services, and setting a value of the indicator based on the determining. In some embodiments, the indicator may be a single bit (e.g. “1” or “0” ) that indicates whether the non-3GPP network supports IMS voice or not. In other embodiments, the indicator may be part of a bit field that includes other parameters or indicators. In yet other embodiments, the indicator may be implied through another parameter or bit field.

FIG. 9 shows an example of another wireless communication method 900, which may be implemented at a wireless device, for selecting non-3GPP access nodes to support IMS services to 5G core networks. The method 900 includes, at step 910, receiving, by a wireless device in a first network, configuration information comprising an indicator of IMS voice services support by an access node in a second network. In some embodiments, the first network may be a 5G core network and the second network may be a non-3GPP access network.

The method 900 includes, at step 920, selectively accessing the IMS voice services in the second network through the access node based on the indicator. In some embodiments, the indicator corresponds to an ability of the access node in the second network to support IMS voice services. For example, if the indicator may be a “1” that indicates the non-3GPP network supports IMS voice, and the wireless device may continue joining that network via that access node. On the other hand, if the indicator is a “0” , which indicates that IMS voice services are not supported in the selected non-3GPP network, the wireless device may choose to not join that network, and proceed to select another network.

In the

methods

800 and 900, and as described in the context of Embodiments One and Two, the configuration information may include an ePDG identifier configuration, a N3IWF identifier configuration, or a N3AN selection information. In some embodiments, the exemplary configuration information may further include a FQDN and/or an IP address. In other embodiments, the second network may be a WLAN, and the configuration information may include at least one of an SSID, an HESSID or a BSSID.

In some embodiments, the configuration information may include additional parameters and/or data structures, including for other networks, as shown in the examples in FIGS. 5-7, and may include the IMS voice indicator at any level of the data structure.

FIG. 10 is a block diagram representation of a portion of an apparatus, in accordance with some embodiments of the presently disclosed technology. An apparatus 1005, such as a base station or a wireless device (or UE) , can include processor electronics 1010 such as a microprocessor that implements one or more of the techniques presented in this document. The apparatus 1005 can include transceiver electronics 1015 to send and/or receive wireless signals over one or more communication interfaces such as antenna (s) 1020. The apparatus 1005 can include other communication interfaces for transmitting and receiving data. Apparatus 1005 can include one or more memories (not explicitly shown) configured to store information such as data and/or instructions. In some implementations, the processor electronics 1010 can include at least a portion of the transceiver electronics 1015. In some embodiments, at least some of the disclosed techniques, modules or functions, including

methods

800 and 900, are implemented using the apparatus 1005.

It is intended that the specification, together with the drawings, be considered exemplary only, where exemplary means an example and, unless otherwise stated, does not imply an ideal or a preferred embodiment. As used herein, “or” is intended to include “and/or” , unless the context clearly indicates otherwise.

Some of the embodiments described herein are described in the general context of methods or processes, which may be implemented in one embodiment by a computer program product, embodied in a computer-readable medium, including computer-executable instructions, such as program code, executed by computers in networked environments. A computer-readable medium may include removable and non-removable storage devices including, but not limited to, Read Only Memory (ROM) , Random Access Memory (RAM) , compact discs (CDs) , digital versatile discs (DVD) , etc. Therefore, the computer-readable media can include a non-transitory storage media. Generally, program modules may include routines, programs, objects, components, data structures, etc. that perform particular tasks or implement particular abstract data types. Computer-or processor-executable instructions, associated data structures, and program modules represent examples of program code for executing steps of the methods disclosed herein. The particular sequence of such executable instructions or associated data structures represents examples of corresponding acts for implementing the functions described in such steps or processes.

Some of the disclosed embodiments can be implemented as devices or modules using hardware circuits, software, or combinations thereof. For example, a hardware circuit implementation can include discrete analog and/or digital components that are, for example, integrated as part of a printed circuit board. Alternatively, or additionally, the disclosed components or modules can be implemented as an Application Specific Integrated Circuit (ASIC) and/or as a Field Programmable Gate Array (FPGA) device. Some implementations may additionally or alternatively include a digital signal processor (DSP) that is a specialized microprocessor with an architecture optimized for the operational needs of digital signal processing associated with the disclosed functionalities of this application. Similarly, the various components or sub-components within each module may be implemented in software, hardware or firmware. The connectivity between the modules and/or components within the modules may be provided using any one of the connectivity methods and media that is known in the art, including, but not limited to, communications over the Internet, wired, or wireless networks using the appropriate protocols.

While this document contains many specifics, these should not be construed as limitations on the scope of an invention that is claimed or of what may be claimed, but rather as descriptions of features specific to particular embodiments. Certain features that are described in this document in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable sub-combination. Moreover, although features may be described above as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination may be directed to a sub-combination or a variation of a sub-combination. Similarly, while operations are depicted in the drawings in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results.

Only a few implementations and examples are described and other implementations, enhancements and variations can be made based on what is described and illustrated in this disclosure.

Claims

A method for wireless communication, implemented at a network node in a first network, the method comprising:

transmitting configuration information comprising an indicator of IMS (Internet Protocol (IP) Multimedia Subsystem) voice services support by an access node in a second network,

wherein the indicator corresponds to an ability of the access node in the second network to support IMS voice services.
The method of claim 1, further comprising:

determining whether the access node in the second network comprises the ability to support IMS voice services; and

setting a value of the indicator based on the determining.
A method for wireless communication, implemented at a wireless device in a first network, the method comprising:

receiving configuration information comprising an indicator of IMS (Internet Protocol (IP) Multimedia Subsystem) voice services support by an access node in a second network; and

selectively accessing the IMS voice services in the second network through the access node based on the indicator, wherein the indicator corresponds to an ability of the access node in the second network to support IMS voice services.
The method of any of claims 1 to 3, wherein the first network is a core network, and wherein the second network in an access network.
The method of any of claims 1 to 4, wherein the configuration information comprises an evolved Packet Data Gateway (ePDG) identifier configuration.
The method of any of claims 1 to 4, wherein the configuration information comprises a non-3GPP Interworking Function (N3IWF) identifier configuration.
The method of any of claims 1 to 4, wherein the configuration information comprises a non-3GPP access node (N3AN) selection information.
The method of any of claims 5 to 7, wherein the configuration information further comprises a Fully Qualified Domain Name (FQDN) or an IP address.
The method of any of claims 1 to 4, wherein the second network is a Wireless Local Area Network (WLAN) , and wherein the configuration information comprises at least one of a service set identifier (SSID) , a homogeneous extended service set identifier (HESSID) or a basic service set identifier (BSSID) .
The method of any of claims 1 to 9, wherein the first network is a 5G core network, and wherein the second network is a non-3GPP access network.
A wireless communications apparatus comprising a processor, wherein the processor is configured to implement a method recited in any of claims 1 to 10.
A computer program product comprising a computer-readable program medium code stored thereupon, the code, when executed by a processor, causing the processor to implement a method recited in any of claims 1 to 10.