WO2022150965A1

WO2022150965A1 - Stand-alone non-public network mobility

Info

Publication number: WO2022150965A1
Application number: PCT/CN2021/071270
Authority: WO
Inventors: Zhuang Liu; Yin Gao; Jiajun Chen; Man ZHANG
Original assignee: Zte Corporation
Priority date: 2021-01-12
Filing date: 2021-01-12
Publication date: 2022-07-21
Also published as: CN115244984A; EP4107984A1; EP4107984A4

Abstract

A wireless communication method for use in a first wireless network node of a first network is disclosed. The method comprises receiving, from a core network, mobility assistance information associated with a wireless terminal and at least one second network, determining a second wireless network node based on the mobility assistance information for the wireless terminal, and handing over the wireless terminal to the second wireless network node.

Description

STAND-ALONE NON-PUBLIC NETWORK MOBILITY

This document is directed generally to wireless communications.

In current 5G network, user equipments (UEs) operating in Stand-alone Non-Public Network (SNPN) access mode only (re) select cells within the selected/registered SNPN, which provides authentication. That is, only intra-SNPN handover is supported, and the inter-SNPN handover or the handover between a Public Land Mobile Network (PLMN) and a SNPN is not supported. However, in order to support service continuity during the UE mobility, the inter-SNPN handover or the handover between a PLMN and a SNPN is proposed herein.

Furthermore, a SNPN is possibly deployed along with subscriptions or credentials owned by an entity separate from the SNPN, and a UE discovers and selects a SNPN, which provides authentication in an external entity. In order to support service continuity, the handover between inter-SNPNs with the same separate entity is described herein, e.g, UE moving from SNPN#1 with separate entity#1 to SNPN#2 with separate entity#1 available; and the handover between a SNPN and a PLMN (where separate entity=PLMN) is described herein.

A SNPN is a network deployed for non-public use which does not rely on network functions provided by a PLMN. A SNPN cell is identified by a PLMN identification and a network ID (NID) .

A SNPN-capable UE may have one or more SNPN subscriptions, and the UE can select and access a SNPN network, while the authentication done by the accessed SNPN or by a Subscription/Credentials Owner (SCO) separate from the accessed SNPN. The separate SCO entity could be a PLMN or other SNPN or an authentication server.

According to the state of the art, during the UE mobility, the UE and the RAN network is not aware of whether other SNPNs or PLMNs can authenticate the UE or whether other SNPNs or PLMNs have the same SCO available with the currently accessed SNPN for authenticating UE. So, the inter-SNPN handover or the handover between a PLMN and a SNPN is not supported at the moment.

The present disclosure relates to a wireless communication method for use in a first wireless network node of a first network. The method comprises:

receiving, from a core network, mobility assistance information associated with a wireless terminal and at least one second network,

determining a second wireless network node based on the mobility assistance information for the wireless terminal, and

handing over the wireless terminal to the second wireless network node.

Various embodiments may preferably implement the following features:

Preferably, the first network is a standalone non-public network, SNPN and the second network is one of a SNPN or a public land mobile network, PLMN.

Preferably, the first network is a PLMN and the second network is a SNPN.

Preferably, the mobility assistance information includes at least one of:

an allowed network list indicating the at least one second network supported by the wireless terminal, or

a restriction indication indicating at least one of:

whether the wireless terminal is allowed to be transferred from one SNPN to another SNPN, or

whether the wireless terminal is allowed to access a PLMN cell.

Preferably, the wireless communication method further comprises determining a target network used in the second wireless network node based on the mobility assistance information.

Preferably, the target network is one of the at least one second network supported by the wireless terminal.

Preferably, the mobility assistance information indicates that the wireless terminal is allowed to be transferred from one SNPN to another SNPN and/or that the wireless terminal is allowed to access the PLMN cell.

Preferably, handing over the wireless terminal to the second wireless network node comprises:

transmitting, to the core network, a handover request message associated with the second wireless network node,

wherein preferably the handover request message includes a target network used in the second wireless network node.

transmitting, to the second wireless network node, a handover request message for the wireless terminal,

wherein preferably the handover request message comprises at least one of:

a target network used in the second wireless network node, or

the mobility assistance information.

Preferably, the wireless communication method further comprises receiving, from the second wireless network node, a handover failure message including the at least one second network supported by the second wireless network node.

Preferably, the wireless communication method further comprises:

receiving, from the core network, a paging message indicating the at least one second network supporting paging the wireless terminal, and

paging the wireless terminal based on the paging message.

Preferably, the wireless communication method further comprises:

receiving, from the core network, a message carrying non-access stratum information of the wireless terminal, wherein the message comprises updated mobility assistance information associated with the wireless terminal and the at least one second network, and

updating the mobility assistance information by the updated mobility assistance information.

The present disclosure relates to a wireless communication method for use in a core network. The method comprises transmitting, to a first wireless network node of a first network, mobility assistance information associated with a wireless terminal and at least one second network.

Various embodiments may preferably implement the following features:

Preferably, the first network is a PLMN and the second network is a SNPN.

Preferably, the mobility assistance information includes at least one of:

a restriction indication indicating at least one of:

whether the wireless terminal is allowed to access a PLMN cell.

Preferably, the wireless communication method comprises:

receiving, from the first wireless network node, a handover request message of handing over the wireless terminal to a second wireless network node, and

transmitting, to the second wireless network node, the handover request message,

wherein the handover request message comprises a target network used in the second wireless network node.

Preferably, the handover request message transmitted to the second wireless network node further comprises the mobility assistance information.

Preferably, the wireless communication method further comprises transmitting, to the first wireless network node, a paging message indicating the at least one second network supporting paging the wireless terminal.

Preferably, the wireless communication method further comprises transmitting, to the first wireless network node, a message carrying non-access stratum information of the wireless terminal, wherein the message comprises updated mobility assistance information associated with the wireless terminal and the at least one second network.

The present disclosure relates to a wireless communication method for use in a second wireless network node. The method comprises receiving a handover request message for handing over a wireless terminal from a first wireless network node of a first network, wherein the handover request message comprises at least one of a target network used in the second network node or mobility assistance information associated with the wireless terminal and at least one second network.

Various embodiments may preferably implement the following features:

Preferably, the first network is a standalone non-public network, SNPN,

wherein the second network is one of a SNPN or a public land mobile network, PLMN, and

wherein the target network is one of a SNPN or a PLMN.

Preferably, the first network is a PLMN, the second network is a SNPN and the target network is a SNPN.

Preferably, the mobility assistance information includes at least one of:

a restriction indication indicating at least one of:

whether the wireless terminal is allowed to access a PLMN cell.

Preferably, the handover request message is received from a core network.

Preferably, the handover request message is received from the first wireless network node.

Preferably, the wireless communication method further comprises:

transmitting, to a core network, a path switch message for a path switch associated with the wireless terminal and the second wireless network node,

wherein the path switch message comprises the target network used in the second wireless network node.

Preferably, the wireless communication method further comprises transmitting, to the first wireless network node, a handover failure message including the at least one second network supported by the second wireless network node.

The present disclosure relates to a first wireless network node. The first wireless network node comprises:

a communication unit, configured to receive, from a core network, mobility assistance information associated with a wireless terminal and at least one second network, and

a processor configured to:

determine a second wireless network node based on the mobility assistance information for the wireless terminal, and

hand over the wireless terminal to the second wireless network node.

Various embodiments may preferably implement the following feature:

Preferably, the processor is further configured to perform any of aforementioned wireless communication methods.

The present disclosure relates to a core network. The core network comprises:

a communication unit, configured to transmit, to a first wireless network node of a first network, mobility assistance information associated with a wireless terminal and at least one second network.

Various embodiments may preferably implement the following feature:

Preferably, the core network further comprises a processor configured to perform any of aforementioned wireless communication methods.

The present disclosure relates to a second wireless network node. The second wireless network node comprises:

a communication unit, configured to receive a handover request message for handing over a wireless terminal from a first wireless network node of a first network,

wherein the handover request message comprises at least one of a target network used in the second network node or mobility assistance information associated with the wireless terminal and at least one second network.

Various embodiments may preferably implement the following feature:

Preferably, the second wireless network node further comprises a processor configured to perform any of aforementioned wireless communication methods.

The present disclosure relates to 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 one of foregoing methods.

The exemplary embodiments disclosed herein are directed to providing features that will become readily apparent by reference to the following description when taken in conjunction with the accompany drawings. In accordance with various embodiments, exemplary systems, methods, devices and computer program products are disclosed herein. It is understood, however, that these embodiments are presented by way of example and not limitation, and it will be apparent to those of ordinary skill in the art who read the present disclosure that various modifications to the disclosed embodiments can be made while remaining within the scope of the present disclosure.

Thus, the present disclosure is not limited to the exemplary embodiments and applications described and illustrated herein. Additionally, the specific order and/or hierarchy of steps in the methods disclosed herein are merely exemplary approaches. Based upon design preferences, the specific order or hierarchy of steps of the disclosed methods or processes can be re-arranged while remaining within the scope of the present disclosure. Thus, those of ordinary skill in the art will understand that the methods and techniques disclosed herein present various steps or acts in a sample order, and the present disclosure is not limited to the specific order or hierarchy presented unless expressly stated otherwise.

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

FIG. 1 shows RRC-Connected mobility handover without Xn interface signaling according to an embodiment of the present disclosure.

FIG. 2 shows RRC-Connected mobility handover with Xn interface signaling according to an embodiment of the present disclosure.

FIG. 3 shows RRC-Idle/inactive mobility (paging UE) according to an embodiment of the present disclosure.

FIG. 4 shows updating SNPN mobility assistance information according to an embodiment of the present disclosure.

FIG. 5 shows an example of a schematic diagram of a wireless terminal according to an embodiment of the present disclosure.

FIG. 6 shows an example of a schematic diagram of a wireless network node according to an embodiment of the present disclosure.

FIG. 7 shows a flowchart of a method according to an embodiment of the present disclosure.

FIG. 8 shows a flowchart of a method according to an embodiment of the present disclosure.

FIG. 9 shows a flowchart of a method according to an embodiment of the present disclosure.

With reference to FIG. 1 an exemplary embodiment of the present disclosure is described. In particular, FIG. 1 shows RRC-Connected mobility handover without Xn interface signaling according to an embodiment of the present disclosure.

In an embodiment, network A could be a SNPN and network B could be another SNPN or a PLMN. Alternatively, network A could be a PLMN and network B could be a SNPN.

In step 1: the 5G core network (5GC) sends an initial context setup request message or a PDU session setup request message to the source gNB to request the source gNB to assign resources on the Uu interface (i.e. the interface between the gNB and the UE) and NG interface (i.e. the interface between the gNB and the 5GC) for one or several PDU session resources towards the UE, including SMA information (SNPN Mobility Assistance information) in the message, where the SMA information includes at least one of the following information: allowed SNPN list, to indicate which SNPN (s) is/are allowed for UE access; SNPN restriction, which includes at least one of the following information: whether the UE is allowed to access different SNPN from currently serving SNPN; and whether the UE is allowed to access a non-SNPN cell (e.g. a PLMN cell) .

The gNB shall store the SMA information for the UE mobility procedure.

Step 2: the indicated PDU session (s) is/are established towards the UE, and the UE is serviced by the source gNB.

Step 3: the UE sends a measurement report to the source gNB to report serving cell and neighbor cell signal quality.

Step 4: the source gNB may decide a target cell (i.e. target gNB) for handover based on the UE measurement report, the gNB shall select a SNPN or a PLMN supported by the target cell according to the stored SMA information, the selected SNPN is either in the allowed SNPN list and meets the SNPN restriction or is the currently serving SNPN; or the selected PLMN shall meet the SNPN restriction as the UE is allowed to access a non-SNPN cell (a PLMN cell) .

Step 5: in the case of the target gNB having no Xn interface with the source gNB, the source gNB sends a next generation application protocol (NGAP) message, e.g. a HANDOVER REQUIRED, to the 5GC to request the preparation of resources at the target network, including the selected SNPN or the selected PLMN to be used in the target network within the message.

Step 6: the 5GC sends a NGAP message, e.g. a HANDOVER REQUEST, to the target gNB for requesting the preparation of resources at the target gNB, including the SMA information (SNPN Mobility Assistance information) and/or the selected SNPN or the selected PLMN to be used within the NAGP message. The target gNB shall store the SMA information for subsequent mobility and the target gNB shall setup the resource in the selected network (SNPN or PLMN) .

Step 7: the target gNB sends a NGAP message, e.g. a HANDOVER ACKOWLEDGE, to the 5GC to inform the required resource has been successfully setup.

If the target gNB cannot support the selected SNPN or the selected PLMN indicated by the HANDOVER REQUEST message and the target gNB may respond with a HANDOVER FAILURE message to the 5GC, including the supported SNPN (s) and/or support PLMN (s) by the target gNB within the message.

Step 8: after the required resource has been successfully setup at the target gNB, the 5GC sends a NGAP message, e.g. HANDOVER COMMAND, to the source gNB to inform the source gNB that resources for the handover have been prepared at the target gNB

Step 9: the source gNB sends an RRC reconfigure message to the UE to request the UE to be handed over to the target gNB.

Step 10: the UE sends an RRC reconfigure complete message to the target gNB to establish connection with the target gNB.

Step 11: the target gNB sends a HANDOVER NOTIFY message to the 5GC to inform the 5GC that the UE has been identified in the target cell and the handover has been completed.

Step 12: after the handover is completed, the source gNB releases the UE context.

Next, with reference to FIG. 2 an exemplary embodiment of the present disclosure is described. In particular, FIG. 2 shows RRC-Connected mobility handover with Xn interface signaling according to an embodiment of the present disclosure.

In the network sharing case, one gNB (cell) can support multiple network sharing, e.g. one gNB (e.g. cell) can be shared with multiple PLMNs or SNPNs. In other words, one gNB (e.g. cell) can support multiple PLMNs or SNPNs as network sharing. The neighbor gNBs may have an Xn interface connected with each other.

Steps 1-4 are similar with steps 1-4 as described with reference to FIG. 1. Therefore, the description thereof is omitted at this point.

Step 5: in the case of the target gNB having an Xn interface with the source gNB, the source gNB sends a XNAP message, e.g. a HANDOVER REQUEST, to the target gNB to request the preparation of resources at the target gNB, including the selected SNPN or the selected PLMN to be used in the target gNB and/or the SMA information (SNPN Mobility Assistance information) within the message. The target gNB shall store SMA information for subsequent mobility and the target gNB shall setup the resource in the select network (the selected SNPN or the selected PLMN) .

Step 6: the target gNB sends a XNAP message, e.g. a HANDOVER REQUEST ACKOWLEDGE, to the source gNB to inform the source gNB about the prepared resources at the target.

If the target gNB cannot support the selected SNPN or the selected PLMN, the target gNB may respond with a HANDOVER PREPARATION FAILURE message to the source gNB, including the supported SNPN (s) and/or support PLMN (s) of the target gNB.

Step 7: the source gNB sends an RRC reconfigure message to the UE to request the UE to be handed over to the target gNB.

Step 8: the UE sends an RRC reconfigure complete message to the target gNB to establish connection with the target gNB.

Step 9: the target gNB sends a NAGP path switch message to the 5GC to request the path switch to the target node, including the selected SNPN or the selected PLMN in the message.

Step 10: the 5GC sends the path switch response message to the target gNB.

Step 11: after the handover is completed, the source gNB releases the UE context.

Next, with reference to FIG. 3 an exemplary embodiment of the present disclosure is described. In particular, FIG. 3 shows RRC-Idle/inactive mobility (paging UE) according to an embodiment of the present disclosure.

Step 1: the 5GC sends a PAGING messing to the gNB, including an allowed paging SNPN list in the message, to indicate which SNPN (s) is/are allowed for paging UE.

Step 2: the gNB takes the received allowed paging SNPN list information into account when determining the cells where paging will be performed.

Next, with reference to FIG. 4 an exemplary embodiment of the present disclosure is described. In particular, FIG. 4 shows updating SNPN mobility assistance information according to an embodiment of the present disclosure.

Step 1: the 5GC sends the NAGP message, e.g. a DOWNLINK NAS TRANSPORT, to the gNB for carrying NAS information to the corresponding UE, including the SMA information (SNPN Mobility Assistance information) within the message.

Step 2: the gNB shall use the received SMA information for subsequent mobility for the corresponding UE and overwrite any previously stored SMA information for the corresponding UE.

In summary, according to embodiments a method for SNPN mobility comprises: the gNB receives the SMA information (SNPN Mobility Assistance information) sent by the 5GC, the gNB selects the target SNPN or PLMN according to the received SMA information, and handover the UE to the target network.

According to an embodiment, the SMA information may include at least one of the following information: an allowed SNPN list, to indicate which SNPN (s) is/are allowed for UE access; a SNPN restriction, which may include at least one of the following information: whether the UE is allowed to access different SNPN from currently serving SNPN; and whether the UE is allowed to access a non-SNPN cell (a PLMN cell) .

In view of the above described handover without an Xn interface between the source gNB and target gNB, the source gNB may select a SNPN or a PLMN to be used in the target network according to the previously received SMA information, that is, the selected SNPN is either in the allowed SNPN list and meets the SNPN restriction or is the currently serving SNPN; or the selected PLMN shall meet the SNPN restriction as the UE is allowed to access a non-SNPN cell (a PLMN cell) .

The source gNB may send a NGAP message, e.g. a HANDOVER REQUIRED, to the 5GC to request the preparation of resources at the target network, including the selected SNPN or the selected PLMN to be used in the target network within the message.

The target gNB may receive the SMA information (SNPN Mobility Assistance information) within the NAGP message, e.g a HANDOVER REQUEST, sent by the 5GC for requesting the preparation of resources, the target gNB shall store it for subsequent mobility.

The target gNB may receive the selected SNPN or the selected PLMN to be used within the NAGP message, e.g. a HANDOVER REQUEST, sent by the 5GC for requesting the preparation of resources, the gNB uses the selected SNPN or the selected PLMN providing services towards to UE.

If the target gNB cannot support the selected SNPN or the selected PLMN, the gNB shall respond with a HANDOVER FAILURE message to the 5GC, including the supported SNPN (s) and/or support PLMN (s) by the target gNB.

In view of the above described handover based on an Xn interface, the source gNB may select a SNPN or a PLMN to be used in the target gNB according to the previously received SMA information, that is, the selected SNPN is either in the allowed SNPN list and meets the SNPN restriction or is the currently serving SNPN; or the selected PLMN shall meet the SNPN restriction as the UE is allowed to access a non-SNPN cell (a PLMN cell) .

The source gNB may send an XNAP message, e.g. a HANDOVER REQUEST, to the target gNB to request the preparation of resources at the target gNB.

The target gNB may receive the SMA information (SNPN Mobility Assistance information) within the XNAP message, e.g. the HANDOVER REQUEST, sent by the source gNB for requesting the preparation of resources, the target gNB shall store it for subsequent mobility.

The target gNB may receive the selected SNPN or the selected PLMN to be used within the XNAP message, e.g. the HANDOVER REQUEST, sent by the source gNB for requesting the preparation of resources, the target gNB uses the selected SNPN or the selected PLMN providing services towards to UE.

If the target gNB cannot support the selected SNPN or the selected PLMN, the target gNB shall respond with a HANDOVER PREPARATION FAILURE message to the source gNB, including the supported SNPN (s) and/or support PLMN (s) of the target gNB.

The target gNB may send a NAGP path switch message to the 5GC to request the path switch to the target node, including the selected SNPN or the selected PLMN in the message.

In view of the above described RRC-Idle/inactive mobility (paging UE) , the gNB may receive the paging message sent by the 5GC, including the allowed paging SNPN list in the message, to indicate which SNPN (s) is/are allowed for paging UE.

The gNB may take such information into account when determining the cells where paging will be performed.

In view of the above described updating the SNPN mobility assistance information, the gNB may receive the SMA information (SNPN Mobility Assistance information) within the NAGP message, e.g. the DOWNLINK NAS TRANSPORT, for carrying NAS information to UE sent by the 5GC, the gNB shall overwrite any previously stored SMA information for the UE at the gNB.

FIG. 5 relates to a schematic diagram of a wireless terminal 50 in an embodiment of the present disclosure. The wireless terminal 50 may be a communication device, a user equipment (UE) , a mobile phone, a laptop, a tablet computer, an electronic book or a portable computer system and is not limited herein. The wireless terminal 50 may include a processor 500 such as a microprocessor or Application Specific Integrated Circuit (ASIC) , a storage unit 510 and a communication unit 520. The storage unit 510 may be any data storage device that stores a program code 512, which is accessed and executed by the processor 500. Embodiments of the storage unit 510 include but are not limited to a subscriber identity module (SIM) , read-only memory (ROM) , flash memory, random-access memory (RAM) , hard-disk, and optical data storage device. The communication unit 520 may a transceiver and is used to transmit and receive signals (e.g. messages or packets) according to processing results of the processor 500. In an embodiment, the communication unit 520 transmits and receives the signals via at least one antenna 522 shown in FIG. 5.

In an embodiment, the storage unit 510 and the program code 512 may be omitted and the processor 500 may include a storage unit with stored program code.

The processor 500 may implement any one of the steps in exemplified embodiments on the wireless terminal 50, e.g., by executing the program code 512.

The communication unit 520 may be a transceiver. The communication unit 520 may as an alternative or in addition be combining a transmitting unit and a receiving unit configured to transmit and to receive, respectively, signals to and from a wireless network node (e.g. a base station) .

FIG. 6 relates to a schematic diagram of a wireless network node 60 in an embodiment of the present disclosure. The wireless network node 60 may be a communication device, a satellite, a base station (BS) , a network entity, a Mobility Management Entity (MME) , Serving Gateway (S-GW) , Packet Data Network (PDN) Gateway (P-GW) , a radio access network (RAN) , a next generation RAN (NG-RAN) , a gNB, a data network, a core network or a Radio Network Controller (RNC) , and is not limited herein. In addition, the wireless network node 60 may comprise (perform) at least one network function such as an access and mobility management function (AMF) , a session management function (SMF) , a user plane function (UPF) , a policy control function (PCF) , an application function (AF) , an application protocol client function, an application protocol server function, a port management registration and allocation function, a port allocation function, etc. The wireless network node 60 may include a processor 600 such as a microprocessor or ASIC, a storage unit 610 and a communication unit 620. The storage unit 610 may be any data storage device that stores a program code 612, which is accessed and executed by the processor 600. Examples of the storage unit 610 include but are not limited to a SIM, ROM, flash memory, RAM, hard-disk, and optical data storage device. The communication unit 620 may be a transceiver and is used to transmit and receive signals (e.g. messages or packets) according to processing results of the processor 600. In an example, the communication unit 620 transmits and receives the signals via at least one antenna 622 shown in FIG. 6.

In an embodiment, the storage unit 610 and the program code 612 may be omitted. The processor 600 may include a storage unit with stored program code.

The processor 600 may implement any steps described in exemplified embodiments on the wireless network node 60, e.g., via executing the program code 612.

The communication unit 620 may be a transceiver. The communication unit 620 may as an alternative or in addition be combining a transmitting unit and a receiving unit configured to transmit and to receive, respectively, signals to and from a wireless terminal (e.g. a user equipment) .

FIG. 7 shows a flowchart of a process according to an embodiment of the present disclosure. The process shown in FIG. 7 may be used in a first wireless network node (e.g. source gNB) of a first network and comprises the following steps:

Step 701: Receive, from a core network, mobility assistance information associated with a wireless terminal and at least one second network.

Step 702: Determine a second wireless network node based on the mobility assistance information for the wireless terminal.

Step 703: Hand over the wireless terminal to the second wireless network node.

In FIG. 7, the first wireless network node receives mobility assistance information (e.g. SMA information) associated with a wireless terminal (e.g. UE) and at least one second network (e.g. network different from the first network) . Based on the mobility assistance information, the first wireless network node determines a second wireless network node for the wireless terminal, e.g., if determining to transfer the wireless terminal to other wireless network node (e.g. when determining the radio quality of the wireless terminal is worsen) . Next, the first wireless network node handing over the wireless terminal to the second wireless network node determined based on the mobility assistance information.

In an embodiment, the first network is a SNPN and the second network is one of a SNPN or a PLMN.

In an embodiment, the second network is different from the second network.

In an embodiment, the first network is a PLMN and the second network is a SNPN.

In an embodiment, the mobility assistance information includes at least one of:

a restriction indication.

The restriction indication indicates at least one of:

whether the wireless terminal is allowed to access a PLMN cell.

In an embodiment, the first wireless network node determines a target network used in the second wireless network node based on the mobility assistance information. The target network may be the same or different from the first network.

Note that, based on the mobility assistance information, the first wireless network node may determine the second wireless network node first and then the target network used in the second wireless network node. For example, in the networks supported by the UE (i.e. the first network and/or the at least one second network supported by the UE) , the second wireless network node may be able to provide the best communication quality to the UE. As an alternative, based on the mobility assistance information, the first wireless network node may determine the target network used for (e.g. supported by) the wireless terminal and then determine the second wireless network node supporting the target network node.

In an embodiment, the target network is one of the at least one second network supported by the wireless terminal. That is, the target network may be in the allowed network list comprised in the mobility assistance information.

In an embodiment, the first wireless network node determining the target network for the wireless terminal represents that the mobility assistance information indicates:

the wireless terminal is allowed to be transferred from one SNPN to another SNPN; and/or

the wireless terminal is allowed to access the PLMN cell, e.g., when the first wireless network node determine the target network for the wireless terminal.

In an embodiment, the first wireless network node hands over (e.g. transfer) the wireless terminal to the second wireless network node by:

wherein preferably the handover request message includes the target network used in the second wireless network node.

In an embodiment, the first wireless network node hands over the wireless terminal to the second wireless network node by transmitting, to the second wireless network node, a handover request message for the wireless terminal. In this embodiment, the handover request message comprises at least one of:

a target network used in the second wireless network node, or

the mobility assistance information.

In an embodiment, the first wireless network node may receive, from the second wireless network node, a handover failure message including the at least one second network supported by the second wireless network node.

In an embodiment, the first wireless network node receives, from the core network, a paging message indicating the at least one second network supporting paging the wireless terminal. The first wireless network node pages the wireless terminal based on the paging message.

In an embodiment, the first wireless network node receives, from the core network, a message carrying NAS information of the wireless terminal, wherein this message comprises updated mobility assistance information associated with the wireless terminal and the at least one second network. The first wireless network node updates the mobility assistance information by the updated mobility assistance information.

FIG. 8 shows a flowchart of a process according to an embodiment of the present disclosure. The process shown in FIG. 8 may be used in a core network (e.g. 5GC) and comprises the following step:

Step 801: Transmit, to a first wireless network node of a first network, mobility assistance information associated with a wireless terminal and at least one second network.

In FIG. 8, the core network transmits mobility assistance information associated with a wireless terminal and at least one second network to a first wireless network node of a first network. In an embodiment, the first network is a SNPN and the second network is one of a SNPN or a PLMN. In an embodiment, the first network is a PLMN and the second network is a SNPN. In an embodiment, the first network is different from the second network.

In an embodiment, the mobility assistance information includes at least one of:

a restriction indication.

In an embodiment, the restriction indication indicates at least one of:

whether the wireless terminal is allowed to access a PLMN cell.

Based on the mobility assistance information, the first wireless network node is able to acknowledge that the other network (s) supported by the wireless terminal and/or that whether the wireless terminal can be transferred (e.g. handed over) to other network (s) .

In an embodiment, the core network receives, from the first wireless network node, a handover request message of handing over the wireless terminal to a second wireless network node. The core network transmits the handover request message to the second wireless network node. In this embodiment, the handover request message comprises a target network used in the second wireless network node. In addition, the handover request message transmitted to the second wireless network node may further comprise the mobility assistance information.

In an embodiment, the core network transmits a paging message to the first wireless network node, wherein the paging message indicating the at least one second network supporting paging the wireless terminal.

In an embodiment, the core network transmits, to the first wireless network node, a message carrying non-access stratum information of the wireless terminal. The message comprises updated mobility assistance information associated with the wireless terminal and the at least one second network.

FIG. 9 shows a flowchart of a process according to an embodiment of the present disclosure. The process shown in FIG. 9 may be used in a second wireless network node (e.g. target gNB) and comprises the following step:

Step 901: Receive a handover request message for handing over a wireless terminal from a first wireless network node of a first network.

In this embodiment, the second wireless network node may receive a handover request message for handing over a wireless terminal from a first wireless network node of a first network. The handover request message comprises at least one of a target network used in the second network node or mobility assistance information associated with the wireless terminal and at least one second network. In an embodiment, the first network is a SNPN and the second network is one of a SNPN or a PLMN. In an embodiment, the first network is a PLMN and the second network is a SNPN. In an embodiment, the first network is different from the second network and/or the target network. In an embodiment, the target network may be one of a SNPN or a PLMN. For example, when the first network is a SNPN, the second network is a SNPN or a PLMN and the target network is a SNPN or a PLMN. As an alternative, when the first network is a PLMN, the second network is a SNPN and the target network is a SNPN.

In an embodiment, the mobility assistance information includes at least one of:

a restriction indication.

In an embodiment, the restriction indication indicates at least one of:

whether the wireless terminal is allowed to access a PLMN cell.

Based on the mobility assistance information, the second wireless network node can acknowledge that the other network (s) (e.g. the network (s) other than the first network) supported by the wireless terminal and/or that whether the wireless terminal can be transferred (e.g. handed over) to other network (s) .

In an embodiment, the handover request message is received from a core network. In this embodiment, there may not be N26 interface between the first wireless network node and the second wireless network node.

In an embodiment, the handover request message is received from the first wireless network node. That is, there may be N26 interface between the first wireless network node and the second wireless network node.

In an embodiment, the second wireless network node transmits, to a core network, a path switch message for a path switch associated with the wireless terminal and the second wireless network node. The path switch message comprises the target network used in the second wireless network node.

In an embodiment, the second wireless network node transmits a handover failure message including the at least one second network supported by the second wireless network node, e.g., when the target network is not supported by the second wireless network node (for example the mobility assistance information is not update to date) .

While various embodiments of the present disclosure have been described above, it should be understood that they have been presented by way of example only, and not by way of limitation. Likewise, the various diagrams may depict an example architectural or configuration, which are provided to enable persons of ordinary skill in the art to understand exemplary features and functions of the present disclosure. Such persons would understand, however, that the present disclosure is not restricted to the illustrated example architectures or configurations, but can be implemented using a variety of alternative architectures and configurations. Additionally, as would be understood by persons of ordinary skill in the art, one or more features of one embodiment can be combined with one or more features of another embodiment described herein. Thus, the breadth and scope of the present disclosure should not be limited by any of the above-described exemplary embodiments.

It is also understood that any reference to an element herein using a designation such as "first, " "second, " and so forth does not generally limit the quantity or order of those elements. Rather, these designations can be used herein as a convenient means of distinguishing between two or more elements or instances of an element. Thus, a reference to first and second elements does not mean that only two elements can be employed, or that the first element must precede the second element in some manner.

Additionally, a person having ordinary skill in the art would understand that information and signals can be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits and symbols, for example, which may be referenced in the above description can be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

A skilled person would further appreciate that any of the various illustrative logical blocks, units, processors, means, circuits, methods and functions described in connection with the aspects disclosed herein can be implemented by electronic hardware (e.g., a digital implementation, an analog implementation, or a combination of the two) , firmware, various forms of program or design code incorporating instructions (which can be referred to herein, for convenience, as "software" or a "software unit” ) , or any combination of these techniques.

To clearly illustrate this interchangeability of hardware, firmware and software, various illustrative components, blocks, units, circuits, and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware, firmware or software, or a combination of these techniques, depends upon the particular application and design constraints imposed on the overall system. Skilled artisans can implement the described functionality in various ways for each particular application, but such implementation decisions do not cause a departure from the scope of the present disclosure. In accordance with various embodiments, a processor, device, component, circuit, structure, machine, unit, etc. can be configured to perform one or more of the functions described herein. The term “configured to” or “configured for” as used herein with respect to a specified operation or function refers to a processor, device, component, circuit, structure, machine, unit, etc. that is physically constructed, programmed and/or arranged to perform the specified operation or function.

Furthermore, a skilled person would understand that various illustrative logical blocks, units, devices, components and circuits described herein can be implemented within or performed by an integrated circuit (IC) that can include a general purpose processor, a digital signal processor (DSP) , an application specific integrated circuit (ASIC) , a field programmable gate array (FPGA) or other programmable logic device, or any combination thereof. The logical blocks, units, and circuits can further include antennas and/or transceivers to communicate with various components within the network or within the device. A general purpose processor can be a microprocessor, but in the alternative, the processor can be any conventional processor, controller, or state machine. A processor can also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other suitable configuration to perform the functions described herein. If implemented in software, the functions can be stored as one or more instructions or code on a computer-readable medium. Thus, the steps of a method or algorithm disclosed herein can be implemented as software stored on a computer-readable medium.

Computer-readable media includes both computer storage media and communication media including any medium that can be enabled to transfer a computer program or code from one place to another. A storage media can be any available media that can be accessed by a computer. By way of example, and not limitation, such computer-readable media can include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to store desired program code in the form of instructions or data structures and that can be accessed by a computer.

In this document, the term "unit" as used herein, refers to software, firmware, hardware, and any combination of these elements for performing the associated functions described herein. Additionally, for purpose of discussion, the various units are described as discrete units; however, as would be apparent to one of ordinary skill in the art, two or more units may be combined to form a single unit that performs the associated functions according embodiments of the present disclosure.

Additionally, memory or other storage, as well as communication components, may be employed in embodiments of the present disclosure. It will be appreciated that, for clarity purposes, the above description has described embodiments of the present disclosure with reference to different functional units and processors. However, it will be apparent that any suitable distribution of functionality between different functional units, processing logic elements or domains may be used without detracting from the present disclosure. For example, functionality illustrated to be performed by separate processing logic elements, or controllers, may be performed by the same processing logic element, or controller. Hence, references to specific functional units are only references to a suitable means for providing the described functionality, rather than indicative of a strict logical or physical structure or organization.

Various modifications to the implementations described in this disclosure will be readily apparent to those skilled in the art, and the general principles defined herein can be applied to other implementations without departing from the scope of this disclosure. Thus, the disclosure is not intended to be limited to the implementations shown herein, but is to be accorded the widest scope consistent with the novel features and principles disclosed herein, as recited in the claims below.

Claims

A wireless communication method for use in a first wireless network node of a first network, the method comprising:

receiving, from a core network, mobility assistance information associated with a wireless terminal and at least one second network,

determining a second wireless network node based on the mobility assistance information for the wireless terminal, and

handing over the wireless terminal to the second wireless network node.
The wireless communication method of claim 1, wherein the first network is a standalone non-public network, SNPN and the second network is one of a SNPN or a public land mobile network, PLMN.
The wireless communication method of claim 1, wherein the first network is a PLMN and the second network is a SNPN.
The wireless communication method of any of claims 1 to 3, wherein the mobility assistance information includes at least one of:

an allowed network list indicating the at least one second network supported by the wireless terminal, or

a restriction indication indicating at least one of:

whether the wireless terminal is allowed to be transferred from one SNPN to another SNPN, or

whether the wireless terminal is allowed to access a PLMN cell.
The wireless communication method of any of claims 1 to 4, further comprising:

determining a target network used in the second wireless network node based on the mobility assistance information.
The wireless communication method of claim 5, wherein the target network is one of the at least one second network supported by the wireless terminal.
The wireless communication method of claim 5 or 6, wherein the mobility assistance information indicates that the wireless terminal is allowed to be transferred from one SNPN to another SNPN and/or that the wireless terminal is allowed to access the PLMN cell.
The wireless communication method of any of claims 1 to 7, wherein handing over the wireless terminal to the second wireless network node comprises:

transmitting, to the core network, a handover request message associated with the second wireless network node,

wherein preferably the handover request message includes a target network used in the second wireless network node.
The wireless communication method of any of claims 1 to 7, wherein handing over the wireless terminal to the second wireless network node comprises:

transmitting, to the second wireless network node, a handover request message for the wireless terminal,

wherein preferably the handover request message comprises at least one of:

a target network used in the second wireless network node, or

the mobility assistance information.
The wireless communication method of claim 9, further comprising:

receiving, from the second wireless network node, a handover failure message including the at least one second network supported by the second wireless network node.
The wireless communication method of any of claims 1 to 10, further comprising:

receiving, from the core network, a paging message indicating the at least one second network supporting paging the wireless terminal, and

paging the wireless terminal based on the paging message.
The wireless communication method of any of claims 1 to 11, further comprising:

receiving, from the core network, a message carrying non-access stratum information of the wireless terminal, wherein the message comprises updated mobility assistance information associated with the wireless terminal and the at least one second network, and

updating the mobility assistance information by the updated mobility assistance information.
A wireless communication method for use in a core network, the method comprising:

transmitting, to a first wireless network node of a first network, mobility assistance information associated with a wireless terminal and at least one second network.
The wireless communication method of claim 13, wherein the first network is a standalone non-public network, SNPN and the second network is one of a SNPN or a public land mobile network, PLMN.
The wireless communication method of claim 13, wherein the first network is a PLMN and the second network is a SNPN.
The wireless communication method of any of claims 13 to 15, wherein the mobility assistance information includes at least one of:

an allowed network list indicating the at least one second network supported by the wireless terminal, or

a restriction indication indicating at least one of:

whether the wireless terminal is allowed to be transferred from one SNPN to another SNPN, or

whether the wireless terminal is allowed to access a PLMN cell.
The wireless communication method of any of claims 13 to 16, further comprising:

receiving, from the first wireless network node, a handover request message of handing over the wireless terminal to a second wireless network node, and

transmitting, to the second wireless network node, the handover request message,

wherein the handover request message comprises a target network used in the second wireless network node.
The wireless communication method of claim 17, wherein the handover request message transmitted to the second wireless network node further comprises the mobility assistance information.
The wireless communication method of any of claims 13 to 18, further comprising:

transmitting, to the first wireless network node, a paging message indicating the at least one second network supporting paging the wireless terminal.
The wireless communication method of any of claims 13 to 18, further comprising:

transmitting, to the first wireless network node, a message carrying non-access stratum information of the wireless terminal, wherein the message comprises updated mobility assistance information associated with the wireless terminal and the at least one second network.
A wireless communication method for use in a second wireless network node, the method comprising:

receiving a handover request message for handing over a wireless terminal from a first wireless network node of a first network,

wherein the handover request message comprises at least one of a target network used in the second network node or mobility assistance information associated with the wireless terminal and at least one second network.
The wireless communication method of claim 21, wherein the first network is a standalone non-public network, SNPN,

wherein the second network is one of a SNPN or a public land mobile network, PLMN, and

wherein the target network is one of a SNPN or a PLMN.
The wireless communication method of claim 21, wherein the first network is a PLMN, the second network is a SNPN and the target network is a SNPN.
The wireless communication method of any of claims 21 to 23, wherein the mobility assistance information includes at least one of:

an allowed network list indicating the at least one second network supported by the wireless terminal, or

a restriction indication indicating at least one of:

whether the wireless terminal is allowed to be transferred from one SNPN to another SNPN, or

whether the wireless terminal is allowed to access a PLMN cell.
The wireless communication method of any of claims 21 to 24, wherein the handover request message is received from a core network.
The wireless communication method of any of claims 21 to 24, wherein the handover request message is received from the first wireless network node.
The wireless communication method of claim 26, further comprising:

transmitting, to a core network, a path switch message for a path switch associated with the wireless terminal and the second wireless network node,

wherein the path switch message comprises the target network used in the second wireless network node.
The wireless communication method of claim 26 or 27, further comprising:

transmitting, to the first wireless network node, a handover failure message including the at least one second network supported by the second wireless network node.
A first wireless network node, comprising:

a communication unit, configured to receive, from a core network, mobility assistance information associated with a wireless terminal and at least one second network, and

a processor configured to:

determine a second wireless network node based on the mobility assistance information for the wireless terminal, and

hand over the wireless terminal to the second wireless network node.
The first wireless network node of claim 29, wherein the processor is further configured to perform a wireless communication method of any one of claims 2 to 12.
A core network, comprising:

a communication unit, configured to transmit, to a first wireless network node of a first network, mobility assistance information associated with a wireless terminal and at least one second network.
The core network of claim 31, further comprising a processor configured to perform a wireless communication method of any one of claims 14 to 20.
A second wireless network node, comprising:

a communication unit, configured to receive a handover request message for handing over a wireless terminal from a first wireless network node of a first network,

wherein the handover request message comprises at least one of a target network used in the second network node or mobility assistance information associated with the wireless terminal and at least one second network.
The second wireless network node of claim 33, further comprising a processor configured to perform a wireless communication method of any one of claims 22 to 28.
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 wireless communication method recited in any one of claims 1 to 28.